Sample records for flaming gorge dam

  1. EIS-0351: Operation of Flaming Gorge Dam, Colorado River Storage Project, Colorado River, UT

    Broader source: Energy.gov [DOE]

    The Secretary of the United States Department of the Interior (Secretary), acting through the Bureau of Reclamation (Reclamation), is considering whether to implement a proposed action under which Flaming Gorge Dam would be operated to achieve the flow and temperature regimes recommended in the September 2000 report Flow and Temperature Recommendations for Endangered Fishes in the Green River Downstream of Flaming Gorge Dam (2000 Flow and Temperature Recommendations), published by the Upper Colorado River Endangered Fish Recovery Program (Recovery Program).

  2. Three-Gorges Dam: Risk to Ancient Fish

    E-Print Network [OSTI]

    Wu, Jianguo "Jingle"

    Three-Gorges Dam: Risk to Ancient Fish THE HUGETHREE-GORGES DAM (TGD) OFTHE Yangtze River is going and animals, as discussed by J. Wu et al. in their Policy Forum "Three-Gorges Dam-- experiment in habitat). The construction of the Gezhou Dam (38 km downstream from the TGD) in 1981 led to sharp declines in the popula

  3. THREE GORGES DAM Matthew Morioka, Alireza Abrishamkar, Yve Kay

    E-Print Network [OSTI]

    Prevedouros, Panos D.

    and greenhouse gas emission: 366 grams of coal is used to generate 1 kWh of electricity, therefore the dam Cost: Est. $29 billion ·32 Generators :·32 Generators : Capacity of 700MW EA ·Total electric generating deterioration and epidemics related to the flood #12;Social Benefits (2/3) -Direct reduction of air pollutant

  4. Evaluation of laboratory test method for determining the potential alkali contribution from aggregate and the ASR safety of the Three-Gorges dam concrete

    SciTech Connect (OSTI)

    Lu Duyou [College of Materials Science and Engineering, Nanjing University of Technology, No. 5 Xin Mafan Road, Nanjing, Jiangsu, 210009 (China)]. E-mail: duyoulu@njut.edu.cn; Zhou, Xiaoling [College of Materials Science and Engineering, Nanjing University of Technology, No. 5 Xin Mafan Road, Nanjing, Jiangsu, 210009 (China); Xu Zhongzi [College of Materials Science and Engineering, Nanjing University of Technology, No. 5 Xin Mafan Road, Nanjing, Jiangsu, 210009 (China); Lan Xianghui [College of Materials Science and Engineering, Nanjing University of Technology, No. 5 Xin Mafan Road, Nanjing, Jiangsu, 210009 (China); Tang Mingshu [College of Materials Science and Engineering, Nanjing University of Technology, No. 5 Xin Mafan Road, Nanjing, Jiangsu, 210009 (China); Fournier, Benoit [ICON/CANMET, Natural Resources Canada, 405 Rocherster Street, Ottawa, ON, K1A 0G1 (Canada)

    2006-06-15T23:59:59.000Z

    The releasable alkali from granite, which was used in the Three-Gorges concrete dam project in China, and from gneiss and feldspar was estimated by extraction in distilled water and super-saturated Ca(OH){sub 2} solution. Results show that: i) the finer the particles and the higher the temperature, the greater and faster the release of alkali; ii) compared with extraction by distilled water, super-saturated Ca(OH){sub 2} solution had a stronger activation on feldspar than on granite and gneiss; iii) for the three rocks tested, thermal activation had the largest effect on gneiss and a lower and similar effect on granite and feldspar. For very fine particles, temperature had a similar effect on the release of alkali by all three rocks. Because the aggregate used in the Three-Gorges dam concrete is non-reactive and a low calcium fly ash was used in the concrete, ASR would not be an issue for the dam, despite the release of alkali from the aggregate into the concrete.

  5. High Dams and Marine-Freshwater Linkages: Effects on Native and Introduced Fauna in the Caribbean

    E-Print Network [OSTI]

    Holmquist, Jeffrey G; Schmidt-Gengenbach, Jutta; Yoshioka, Beverly Buchanan

    1998-01-01T23:59:59.000Z

    in relation to hydroelectric dams in the Amazon Basin.effects of the Kafue Gorge Dam. Transactions of the Americanof fishways and impact of dams on the migration of grayling

  6. Assessing the influence of environmental impact assessments on science and policy: An analysis of the Three Gorges Project

    E-Print Network [OSTI]

    Tullos, Desiree

    Assessing the influence of environmental impact assessments on science and policy: An analysis Keywords: Environmental impact assessment Dams Three Gorges Project Uncertainty Prioritization a b s t r exist between the scientific interest (via number of publications) in environmental impacts and (a

  7. Q00906010024 rock check dam

    E-Print Network [OSTI]

    00906010024 rock check dam Q00906010025 rock check dam Q00906010021 rock check dam Q00906010022 rock check dam Q00906010027 rock check dam Q00906010026 rock check dam Q00906010018 rock check dam Q00906010023 rock check dam Q00906010011 rock check dam Q00906010008 rock check dam Q00906010007 rock check dam Q

  8. Dam Safety Program (Maryland)

    Broader source: Energy.gov [DOE]

    The Dam Safety Division within the Department of the Environment is responsible for administering a dam safety program to regulate the construction, operation, and maintenance of dams to prevent...

  9. V00306010057 rock check dam

    E-Print Network [OSTI]

    ¬« ¬« ¬« ¬« ¬« XY! 16-020 16-030(c) 16-026(l) 16-028(c) 16-026(l) V00306010057 rock check dam V00306010012 rock check dam V00306010040 rock check dam V00306010039 rock check dam V00306010058 rock check dam V00306010064 rock check dam V00306010061 rock check dam V00306010062 rock check dam V00306010063

  10. Dam Safety (Pennsylvania)

    Broader source: Energy.gov [DOE]

    The Pennsylvania Department of Environmental Protection's Division of Dam Safety provides for the regulation and safety of dams and reservoirs throughout the Commonwealth in order to protect the...

  11. V01406010015 rock check dam

    E-Print Network [OSTI]

    XY! ¬« ¬« V01406010015 rock check dam V01406010014 rock check dam V01406010013 rock check dam 1501403010012 earthen berm V01403010008 earthen berm V01406010003 rock check dam V01406010004 rock check dam V01406010010 rock check dam V01406010011 rock check dam 15-0651 15-0307 15-0588 15-0532 15-0575 stormdrain 7160

  12. Dam Safety Regulation (Mississippi)

    Broader source: Energy.gov [DOE]

    The purpose of the Dam Safety Regulation is to ensure that all dams constructed in the state of Mississippi are permitted and thus do not potentially harm wildlife, water supplies and property. ...

  13. Dam Safety (Delaware)

    Broader source: Energy.gov [DOE]

    The Delaware Dam Safety Law was adopted in 2004 and provides the framework for proper design, construction, operation, maintenance, and inspection of dams in the interest of public health, safety,...

  14. Dam Safety Regulations (Connecticut)

    Broader source: Energy.gov [DOE]

    All dams, except those owned by the U.S., are under the jurisdiction of these regulations. These dams will be classified by hazard rating, and may be subject to periodic inspections. The...

  15. Power Plant Dams (Kansas)

    Broader source: Energy.gov [DOE]

    This act states the provisions for erection and maintenance of dams. When any person, corporation or city may be desirous of erecting and maintaining a milldam or dam for generating power across...

  16. J00206010020 rock check dam

    E-Print Network [OSTI]

    XY! J00206010020 rock check dam J00206010023 rock check dam 09-009 09-009 09-009 PJ-SMA-2 0.901 Acres J00206010021 rock check dam J00206010019 rock check dam J00206010014 rock check dam J00203010007 Smith DATE: 14-November-2014 REVISION NUMBER: 8 XY! IP sampler location Berm Channel/swale Check dam

  17. W02106010008 rock check dam

    E-Print Network [OSTI]

    W-SMA-14.1 5.169 Acres W02106010008 rock check dam W02106010009 rock check dam W02106010010 rock check dam W02106010011 rock check dam W02106010012 rock check dam W02103010018 earthen berm W02103010016 dam Established vegetation Seed and mulch Sediment trap/basin Gabion Cap SWMU boundary SMA drainage

  18. T00406010008 rock check dam

    E-Print Network [OSTI]

    XY! ¬« T00406010008 rock check dam T00406010009 rock check dam T00406010010 rock check dam T00406010011 rock check dam T-SMA-2.85 0.344 Acres 35-014(g) 35-016(n) T00406010005 rock check dam T00406010006 rock check dam T00403090004 curb T00402040007 established vegetation, green hatch area 7200 7200 7180

  19. Dams – Fishways (Iowa)

    Broader source: Energy.gov [DOE]

    No permanent dam or obstruction may be placed in the waters of the state without providing for fish passage.

  20. Remote sensing analysis of the Gorge of the Nile, Ethiopia with emphasis on DejenGohatsion region

    E-Print Network [OSTI]

    Gani, Nahid DS

    Remote sensing analysis of the Gorge of the Nile, Ethiopia with emphasis on Dejen­Gohatsion region and geomorphological information in order to understand the geological controls on the Gorge of the Nile in Ethiopia

  1. Flame front configuration of turbulent premixed flames

    SciTech Connect (OSTI)

    Furukawa, Junichi [Tokyo Metropolitan Technical Coll. (Japan). Dept. of Mechanical Engineering] [Tokyo Metropolitan Technical Coll. (Japan). Dept. of Mechanical Engineering; Maruta, Kaoru [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science] [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science; Hirano, Toshisuke [Univ. of Tokyo (Japan). Dept. of Chemical System Engineering] [Univ. of Tokyo (Japan). Dept. of Chemical System Engineering

    1998-02-01T23:59:59.000Z

    The present study is performed to explore dependence of the wrinkle scale of propane-air turbulent premixed flames on the characteristics of turbulence in the nonreacting flow, burner size, and mixture ratio. The wrinkle scales are examined and expressed in the frequency distribution of the radii of flame front curvatures. The average wrinkle scale depends not only on the characteristics of turbulence in the nonreacting flow but also on burner diameter and mixture ratio. The average wrinkle scale of a lean propane-air flame is larger than those of the near stoichiometric and rich flames. The smallest wrinkle scale of turbulent premixed flame is in the range of 0.75--1.0 mm, which is much larger than the Kolmogorov scale of turbulence in the nonreacting flow.

  2. Dam Safety Program (Florida)

    Broader source: Energy.gov [DOE]

    Dam safety in Florida is a shared responsibility among the Florida Department of Environmental Protection (FDEP), the regional water management districts, the United States Army Corps of Engineers ...

  3. Dams, Dikes, and Other Devices; Dam Safety Program (North Dakota)

    Broader source: Energy.gov [DOE]

    These regulations govern the permitting, construction, operation, inspection, and hazard classifications of dams, dikes, and other water impoundments. The Dam Safety page of the State Water...

  4. Dam Safety Standards (New Jersey)

    Broader source: Energy.gov [DOE]

    These rules set forth procedures for application to construct, repair or modify a dam and set standards for design and maintenance of dams. These rules also establish a dam inspection procedure....

  5. Montana Dam Safety Act (Montana)

    Broader source: Energy.gov [DOE]

    This Act establishes the state's interest in the construction of dams for water control and regulation and for hydropower generation purposes. It regulates dam construction, operation, and...

  6. On the Flame Height Definition for Upward Flame Spread 

    E-Print Network [OSTI]

    Consalvi, Jean L; Pizzo, Yannick; Porterie, Bernard; Torero, Jose L

    2007-01-01T23:59:59.000Z

    Flame height is defined by the experimentalists as the average position of the luminous flame and, consequently is not directly linked with a quantitative value of a physical parameter. To determine flame heights from ...

  7. China Three Gorges Project Corporation CTGPC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof Energy 2,AUDIT REPORTEnergy Offshore Place: SpainGuajirugroSolarCurtainChinaGorges

  8. Dams (South Dakota)

    Broader source: Energy.gov [DOE]

    Dam construction in South Dakota requires a Location Notice or a Water Right Permit. A Location Notice is a form that must be filed with the County Register of Deeds, and is the only paperwork...

  9. Regulation of Dams (Indiana)

    Broader source: Energy.gov [DOE]

    The owner of a dam is required to maintain the structure in good condition, and notify the Department of Environmental Management upon the sale or transfer of ownership of the structure. The...

  10. Dam Safety (North Carolina)

    Broader source: Energy.gov [DOE]

    North Carolina Administrative Code Title 15A, Subchapter 2K lays out further regulations for the design, approval, construction, maintenance, and inspection of dams to ensure public safety and...

  11. Dam Safety (Michigan)

    Broader source: Energy.gov [DOE]

    This rule requires that anyone who desires to construct a dam that is 6 feet or more in height and impounds 5 surface acres or more at the design flood elevation, must first obtain a permit from...

  12. Approaches to modeling thermonuclear flames

    E-Print Network [OSTI]

    J. C. Niemeyer; W. K. Bushe; G. R. Ruetsch

    Turbulence-flame interactions of thermonuclear fusion flames occurring in Type Ia Supernovae were studied by means of incompressible DNS with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its

  13. Flood Protection and Dam Safety (Virginia)

    Broader source: Energy.gov [DOE]

    All dams in Virginia are subject to the Dam Safety Act and Dam Safety Regulations unless specifically excluded. A dam is excluded if it: (a) is less than six feet high; (b) has a maximum capacity...

  14. Mills, Dams, and Reservoirs (Massachusetts)

    Broader source: Energy.gov [DOE]

    This chapter of the Massachusetts General Laws outlines procedures to settle disputes regarding the construction and operation of dams on non-navigable waters. Dam construction or alteration is...

  15. INTERNATIONAL COMMISSION ON LARGE DAMS

    E-Print Network [OSTI]

    Bowles, David S.

    FOR ESTIMATION OF THE PROBABILITY OF FAILURE OF DAMS FOR USE IN QUANTITATIVE RISK ASSESSMENT (* ) Robin FELL: · Failure modes identification · Analysis to estimate the probability of failure of the dam · Calculation the methods available for estimating the probability of failure of embankment and concrete dams, for normal

  16. Wim van Dam CURRICULUM VITAE

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    Wim van Dam CURRICULUM VITAE Department of Computer Science Work: +1-805-893 5211 Harold Frank Hall in physics. #12;Curriculum Vitae Wim van Dam, June 2008 2 PUBLICATIONS Journal and Conference Articles [1] "Quantum Algorithms for Algebraic Problems", Andrew M. Childs and Wim van Dam, to appear in Reviews

  17. Temporary Restoration of Bull Trout Passage at Albeni Falls Dam, 2008 Progress Report.

    SciTech Connect (OSTI)

    Bellgraph, Brian J. [Pacific Northwest National Laboratory

    2009-03-31T23:59:59.000Z

    The goal of this project is to provide temporary upstream passage of bull trout around Albeni Falls Dam on the Pend Oreille River, Idaho. Our specific objectives are to capture fish downstream of Albeni Falls Dam, tag them with combination acoustic and radio transmitters, release them upstream of Albeni Falls Dam, and determine if genetic information on tagged fish can be used to accurately establish where fish are located during the spawning season. In 2007, radio receiving stations were installed at several locations throughout the Pend Oreille River watershed to detect movements of adult bull trout; however, no bull trout were tagged during that year. In 2008, four bull trout were captured downstream of Albeni Falls Dam, implanted with transmitters, and released upstream of the dam at Priest River, Idaho. The most-likely natal tributaries of bull trout assigned using genetic analyses were Grouse Creek (N = 2); a tributary of the Pack River, Lightning Creek (N = 1); and Rattle Creek (N = 1), a tributary of Lightning Creek. All four bull trout migrated upstream from the release site in Priest River, Idaho, were detected at monitoring stations near Dover, Idaho, and were presumed to reside in Lake Pend Oreille from spring until fall 2008. The transmitter of one bull trout with a genetic assignment to Grouse Creek was found in Grouse Creek in October 2008; however, the fish was not found. The bull trout assigned to Rattle Creek was detected in the Clark Fork River downstream from Cabinet Gorge Dam (approximately 13 km from the mouth of Lightning Creek) in September but was not detected entering Lightning Creek. The remaining two bull trout were not detected in 2008 after detection at the Dover receiving stations. This report details the progress by work element in the 2008 statement of work, including data analyses of fish movements, and expands on the information reported in the quarterly Pisces status reports.

  18. Perspectives on Dam Removal: York Creek Dam and the Water Framework Directive

    E-Print Network [OSTI]

    Lawrence, Justin E; Pollak, Josh D; Richmond, Sarah F

    2008-01-01T23:59:59.000Z

    Sacramento. Graf, W. L. , 1999: Dam Nation: A GeographicCensus of American Dams and Their Large-Scale HydrologicEcological Effects of Dams: A Geomorphic Perspective.

  19. Dam Safety Rules (West Virginia)

    Broader source: Energy.gov [DOE]

    This establishes requirements relating to the design, placement, construction, enlargement, alteration, removal, abandonment, and repair of dams and also establishes requirements to govern the...

  20. Regulations and Permits Related to Dams (Vermont)

    Broader source: Energy.gov [DOE]

    Vermont law requires a permit, or a dam order, for the construction, alteration, or removal of dams impounding more than 500,000 cubic feet of water, including any accumulated sediments. Dam...

  1. War damages and reconstruction of Peruca dam

    SciTech Connect (OSTI)

    Nonveiller, E. [Univ. of Zagreb (Croatia). Faculty of Civil Engineering] [Univ. of Zagreb (Croatia). Faculty of Civil Engineering; Rupcic, J. [Univ. of Zagreb (Croatia). Faculty of Civil Engineering] [Univ. of Zagreb (Croatia). Faculty of Civil Engineering; [Elektroprojekt Consulting Engineering, Zagreb (Croatia); Sever, Z. [Elektroprojekt Consulting Engineering, Zagreb (Croatia)] [Elektroprojekt Consulting Engineering, Zagreb (Croatia)

    1999-04-01T23:59:59.000Z

    The paper describes the heavy damages caused by blasting in the Peruca rockfill dam in Croatia in January 1993. Complete collapse of the dam by overtopping was prevented through quick action of the dam owner by dumping clayey gravel on the lowest sections of the dam crest and opening the bottom outlet of the reservoir, thus efficiently lowering the water level. After the damages were sufficiently established and alternatives for restoration of the dam were evaluated, it was decided to construct a diaphragm wall through the damaged core in the central dam part as the impermeable dam element and to rebuild the central clay core at the dam abutments. Reconstruction works are described.

  2. Safety of Dams and Reservoirs Act (Nebraska)

    Broader source: Energy.gov [DOE]

    This act regulates dams and associated reservoirs to protect health and public safety and minimize adverse consequences associated with potential dam failure. The act describes the responsibilities...

  3. Division of Water, Part 673: Dam Safety Regulations (New York)

    Broader source: Energy.gov [DOE]

    These regulations address dam safety, define dam hazard categories and inspection procedures, and apply to any owner of a dam. Dam owners are required to maintain dams in a safe condition at all...

  4. DAMS: Distributed Adaptive Metaheuristic Selection Bilel Derbel

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    DAMS: Distributed Adaptive Metaheuristic Selection Bilel Derbel Université Lille 1 LIFL ­ CNRS Metaheuristic Selection (DAMS) frame- work. DAMS is dedicated to adaptive optimization in distributed environments. Given a set of metaheuristics, the goal of DAMS is to coordinate their local execution

  5. EFFECT OF ENCROACHMENT OF WANAPUM DAM RESERVOIR ON FISH PASSAGE OVER ROCK ISLAND DAM, COLUMBIA RIVER

    E-Print Network [OSTI]

    EFFECT OF ENCROACHMENT OF WANAPUM DAM RESERVOIR ON FISH PASSAGE OVER ROCK ISLAND DAM, COLUMBIA the lower sections of the three fish ladders at Rock Island Dam, 61 km upstream from Wanapum Dam of the center and left-bank fish ladders of Rock Island Dam were rebuilt and a new sequence of spill patterns

  6. Dynamics and structure of stretched flames

    SciTech Connect (OSTI)

    Law, C.K. [Princeton Univ., NJ (United States)

    1993-12-01T23:59:59.000Z

    This program aims to gain fundamental understanding on the structure, geometry, and dynamics of laminar premixed flames, and relate these understanding to the practical issues of flame extinction and stabilization. The underlying fundamental interest here is the recent recognition that the response of premixed flames can be profoundly affected by flame stretch, as manifested by flow nonuniformity, flame curvature, and flame/flow unsteadiness. As such, many of the existing understanding on the behavior of premixed flames need to be qualitatively revised. The research program consists of three major thrusts: (1) detailed experimental and computational mapping of the structure of aerodynamically-strained planar flames, with emphasis on the effects of heat loss, nonequidiffusion, and finite residence time on the flame thickness, extent of incomplete reaction, and the state of extinction. (2) Analytical study of the geometry and dynamics of stretch-affected wrinkled flame sheets in simple configurations, as exemplified by the Bunsen flame and the spatially-periodic flame, with emphasis on the effects of nonlinear stretch, the phenomena of flame cusping, smoothing, and tip opening, and their implications on the structure and burning rate of turbulent flames. (3) Stabilization and blowoff of two-dimensional inverted premixed and stabilization and determining the criteria governing flame blowoff. The research is synergistically conducted through the use of laser-based diagnostics, computational simulation of the flame structure with detailed chemistry and transport, and mathematical analysis of the flame dynamics.

  7. Dam Construction and Maintenance (Minnesota)

    Broader source: Energy.gov [DOE]

    Dams may be constructed, improved, or repaired on private, non-navigable waters subject to certain timelines; however, previously-developed hydropower mechanisms cannot be disrupted. The State may...

  8. Use, Maintenance, Removal, Inspections, and Safety of Dams (Iowa)

    Broader source: Energy.gov [DOE]

    This section describes operating plans for dams with movable structures, as well as procedures for raising or lowering of impoundment levels, dam removal, and dam safety inspections.

  9. advanced flame quality: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to modeling thermonuclear flames CiteSeer Summary: Turbulence-flame interactions of thermonuclear fusion flames occurring in Type Ia Supernovae were studied by means of...

  10. aircraft cargo flame: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to modeling thermonuclear flames CiteSeer Summary: Turbulence-flame interactions of thermonuclear fusion flames occurring in Type Ia Supernovae were studied by means of...

  11. aerosol flame deposition: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to modeling thermonuclear flames CiteSeer Summary: Turbulence-flame interactions of thermonuclear fusion flames occurring in Type Ia Supernovae were studied by means of...

  12. On the critical flame radius and minimum ignition energy for spherical flame initiation

    SciTech Connect (OSTI)

    Chen, Zheng; Burke, M. P.; Ju, Yiguang

    2011-01-01T23:59:59.000Z

    Spherical flame initiation from an ignition kernel is studied theoretically and numerically using different fuel/oxygen/helium/argon mixtures (fuel: hydrogen, methane, and propane). The emphasis is placed on investigating the critical flame radius controlling spherical flame initiation and its correlation with the minimum ignition energy. It is found that the critical flame radius is different from the flame thickness and the flame ball radius and that their relationship depends strongly on the Lewis number. Three different flame regimes in terms of the Lewis number are observed and a new criterion for the critical flame radius is introduced. For mixtures with Lewis number larger than a critical Lewis number above unity, the critical flame radius is smaller than the flame ball radius but larger than the flame thickness. As a result, the minimum ignition energy can be substantially over-predicted (under-predicted) based on the flame ball radius (the flame thickness). The results also show that the minimum ignition energy for successful spherical flame initiation is proportional to the cube of the critical flame radius. Furthermore, preferential diffusion of heat and mass (i.e. the Lewis number effect) is found to play an important role in both spherical flame initiation and flame kernel evolution after ignition. It is shown that the critical flame radius and the minimum ignition energy increase significantly with the Lewis number. Therefore, for transportation fuels with large Lewis numbers, blending of small molecule fuels or thermal and catalytic cracking will significantly reduce the minimum ignition energy.

  13. Citer ce texte comme : PTILLON J.-M. (2012) Historique des fouilles de R. de Saint-Prier dans les sites palolithiques des gorges de la Save (Lespugue, Haute-Garonne).

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    2012-01-01T23:59:59.000Z

    dans les sites paléolithiques des gorges de la Save (Lespugue, Haute-Garonne). Préhistoire du Sud gorges de la Save (Lespugue, Haute-Garonne) Jean-Marc Pétillon CNRS, laboratoire TRACES (UMR 5608) Maison les sites paléolithiques des gorges de la Save (Lespugue, Haute-Garonne). Ce texte s

  14. Dams and Reservoirs Safety Act (South Carolina)

    Broader source: Energy.gov [DOE]

    The Dams and Reservoirs Safety Act provides for the certification and inspection of dams in South Carolina and confers regulatory authority on the Department of Health and Environmental Control....

  15. Georgia Safe Dams Act of 1978 (Georgia)

    Broader source: Energy.gov [DOE]

    The purpose of the Georgia Safe Dams Act is to provide regulation, inspection and permitting of dams to the State. The Director of the Environmental Protection Division (EPD) is responsible for...

  16. The geomorphic influences of beaver dams and failures of beaver dams

    E-Print Network [OSTI]

    The geomorphic influences of beaver dams and failures of beaver dams David R. Butlera,T, George P millions to low billions of cubic meters range. Failure of beaver dams is a more common phenomenon than often assumed in the literature. During the past 20 years, numerous cases of dam failure have been

  17. GATC Flanking Sequences Regulate Dam Activity: Evidence for how Dam Specificity may Influence

    E-Print Network [OSTI]

    Reich, Norbert O.

    GATC Flanking Sequences Regulate Dam Activity: Evidence for how Dam Specificity may Influence pap coli DNA adenine methyltransferase (Dam) plays essential roles in DNA replication, mismatch repair and gene regulation. The differential methylation by Dam of the two GATC sequences in the pap promoter

  18. Ethanol Consumption by Rat Dams During Gestation,

    E-Print Network [OSTI]

    Galef Jr., Bennett G.

    Ethanol Consumption by Rat Dams During Gestation, Lactation and Weaning Increases Ethanol examined effects of ethanol consumption in rat dams during gestation, lactation, and weaning on voluntary ethanol consumption by their adolescent young. We found that exposure to an ethanol-ingesting dam

  19. Viscoplastic dam breaks and the Bostwick consistometer

    E-Print Network [OSTI]

    Balmforth, Neil

    Viscoplastic dam breaks and the Bostwick consistometer N. J. Balmforth, a R. V. Craster, b P'Informazione, Universit`a di Milano, Crema, Italy Abstract We present a theoretical and experimental analysis of the dam the broken dam) that may assist an experimentalist to unravel those dependences. Experiments are conducted

  20. ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM

    E-Print Network [OSTI]

    ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON, 1959 :y .iiJA/i-3ri ^' WUUUi. ANNUAL FISH PASSAGE REPORT - ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON, 1959 by Paul D. Zimmer, Clifton and observations 10 Summary 13 #12;#12;ANNUAL FISH PASSAGE REPORT - ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON

  1. The design of avalanche protection dams

    E-Print Network [OSTI]

    Boyer, Edmond

    The design of avalanche protection dams Recent practical & theoretical developments://ec.europa.eu/research/research-eu #12;The design of avalanche protection dams Recent practical and theoretical developments Edited by T: Top left: Mounds and catching dam in Neskaupstaður, eastern Iceland, photo: Tómas Jóhannesson. Top

  2. ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM

    E-Print Network [OSTI]

    ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON 1960 . SPECIAL SCIENTIFIC ISLAND DAM COLUMBIA RIVER, WASHINGTON, 1960 by Paul D. Zimmer and Clifton C. Davidson United States Fish This annual report of fishway operations at Rock Island Dam in 1960 is dedicated to the memory of co

  3. On Quantum Computation Theory Wim van Dam

    E-Print Network [OSTI]

    ten Cate, Balder

    On Quantum Computation Theory Wim van Dam #12;#12;On Quantum Computation Theory #12;ILLC woensdag 9 oktober 2002, te 14.00 uur door Willem Klaas van Dam geboren te Breda. #12;Promotor: Prof. dr. P Dam, 2002 ISBN: 90­5776­091­6 #12;" . . . Many errors have been made in the world which today

  4. ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM

    E-Print Network [OSTI]

    42) ANNUAL FISH PASSAGE REPORT ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON 1961 Marine Biological. McKeman, Director ANNUAL FISH PASSAGE REPORT - ROCK ISLAND DAM COLUMBIA RIVER, WASHINGTON, 1961--Fisheries No. 421 Washington, D. C. April 1962 #12;Rock Island Dam, Columbia River, Washington ii #12;CONTENTS

  5. Annual Fish Passage Report -Rock Island Dam

    E-Print Network [OSTI]

    Annual Fish Passage Report - Rock Island Dam Columbia River, Washington, 1965 By Paul D. Zimmer L. McKeman, Director Annual Fish Passage Report - Rock Island Dam Columbia River, Washington, 1965;#12;Annual Fish Passage Report - Rock Island Dam Columbia River, Washington, 1965 By PAUL D. ZIMMER, Fishery

  6. Dam Design and Construction (Wisconsin)

    Broader source: Energy.gov [DOE]

    These regulations apply to dams that are not owned by the U.S. government and (a) have a structural height of more than 6 feet and a maximum storage capacity of 50 acre–feet or more of water, (b)...

  7. Flame Spectral Analysis for Boiler Control 

    E-Print Network [OSTI]

    Metcalfe, C. I.; Cole, W. E.; Batra, S. K.

    1987-01-01T23:59:59.000Z

    FLAME SPECTRAL ANALYSIS FOR BOILER CONTROL CHRISTOPHER I. METCALFE WILLIAM E. COLE SUSHIL K. BATRA Tecogen, Inc. ( A Subsidiary of Thermo Electron Corporation) Waltham, Massachusetts ABSTRACT SPECTRAL FLAME ANALYSIS FOR BURNER CONTROL During...

  8. Transient Supersonic Methane-Air Flames

    E-Print Network [OSTI]

    Richards, John L.

    2012-07-16T23:59:59.000Z

    The purpose of this study was to investigate the thermochemical properties of a transient supersonic flame. Creation of the transient flame was controlled by pulsing air in 200 millisecond intervals into a combustor filled with flowing methane...

  9. Characterization of acoustically forced swirl flame dynamics

    E-Print Network [OSTI]

    Lieuwen, Timothy C.

    of the flame to acoustic excitation is required. This study presents an analysis of phase-locked OH PLIF images of acoustically excited swirl flames, to identify the key controlling physical processes and qualitatively discuss, and whose relative significance depends upon forcing frequency, amplitude of excitation, and flame

  10. Premixed-gas flames Paul D. Ronney

    E-Print Network [OSTI]

    Premixed-gas flames Paul D. Ronney Department of Aerospace and Mechanical Engineering University of Southern California, Los Angeles, CA 90089-1453 USA ronney@usc.edu Keywords: Microgravity; premixed-gas; cool flames; turbulence. Reference: Ronney, P. D., "Premixed-Gas Flames," in: Microgravity Combustion

  11. Electric-field-induced flame speed modification

    SciTech Connect (OSTI)

    Marcum, S.D. [Department of Physics, Miami University, Oxford, OH 45056 (United States); Ganguly, B.N. [Air Force Research Laboratory, Wright-Patterson AFB, OH 45433 (United States)

    2005-10-01T23:59:59.000Z

    The effects of pulsed and continuous DC electric fields on the reaction zones of premixed propane-air flames have been investigated using several types of experimental measurements. All observed effects on the flame are dependent on the applied voltage polarity, indicating that negatively charged flame species do not play a role in the perturbation of the reaction zone. Experiments designed to characterize the electric-field-induced modifications of the shape and size of the inner cone, and the concomitant changes in the temperature profiles of flames with equivalence ratios between 0.8 and 1.7, are also reported. High-speed two-dimensional imaging of the flame response to a pulsed DC voltage shows that the unperturbed conical flame front (laminar flow) is driven into a wrinkled laminar flamelet (cellular) geometry on a time scale of the order of 5 ms. Temperature distributions derived from thin filament pyrometry (TFP) measurements in flames perturbed by continuous DC fields show similar large changes in the reaction zone geometry, with no change in maximum flame temperature. All measurements are consistent with the observed flame perturbations being a fluid mechanical response to the applied field brought about by forcing positive flame ions counter to the flow. The resulting electric pressure decreases Lewis numbers of the ionic species and drives the effective flame Lewis number below unity. The observed increases in flame speed and the flame fronts trend toward turbulence can be described in terms of the flame front wrinkling and concomitant increase in reaction sheet area. This effect is a potentially attractive means of controlling flame fluid mechanical characteristics. The observed effects require minimal input electrical power (<1 W for a 1 kW burner) due to the much better electric field coupling achieved in the present experiments compared to the previous studies.

  12. Flex-flame burner and combustion method

    DOE Patents [OSTI]

    Soupos, Vasilios (Chicago, IL); Zelepouga, Serguei (Hoffman Estates, IL); Rue, David M. (Chicago, IL); Abbasi, Hamid A. (Naperville, IL)

    2010-08-24T23:59:59.000Z

    A combustion method and apparatus which produce a hybrid flame for heating metals and metal alloys, which hybrid flame has the characteristic of having an oxidant-lean portion proximate the metal or metal alloy and having an oxidant-rich portion disposed above the oxidant lean portion. This hybrid flame is produced by introducing fuel and primary combustion oxidant into the furnace chamber containing the metal or metal alloy in a substoichiometric ratio to produce a fuel-rich flame and by introducing a secondary combustion oxidant into the furnace chamber above the fuel-rich flame in a manner whereby mixing of the secondary combustion oxidant with the fuel-rich flame is delayed for a portion of the length of the flame.

  13. Perspectives on Dam Removal: York Creek Dam and the Water Framework Directive

    E-Print Network [OSTI]

    Lawrence, Justin E; Pollak, Josh D; Richmond, Sarah F

    2008-01-01T23:59:59.000Z

    3. Long-profile of York Creek (figure adapted from report byFigure 5. Facies map for York Creek about 100 ft downstreamon Dam Removal: York Creek Dam and the Water Framework

  14. Destruction or Alteration of a Dam (Iowa)

    Broader source: Energy.gov [DOE]

    Permission from the Environmental Protection Commission is required prior to the removal, destruction, or alteration that results in a lower water level of any existing dam.

  15. DROWNED AND DAMMED Colonial Capitalism and Flood Control

    E-Print Network [OSTI]

    Sussex, University of

    DROWNED AND DAMMED Colonial Capitalism and Flood Control in Eastern India ROHAN D, Jawaharlal Nehru University, New Delhi. Drowned and Dammed comprehensively reconsiders the debate with physical infrastructure such as embankments, canal networks, and inevitably the Hirakud Dam. In seeking

  16. Fact Sheet - Myths & Facts about the lower Snake River dams ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Myths and facts about the lower Snake River dams MYTH: The four lower Snake River dams are low value. FACT: It costs about 5 per megawatt-hour to produce power at the dams. The...

  17. Optimal Dam Construction under Climate Change Uncertainty and Anticipated Learning

    E-Print Network [OSTI]

    Cameron-Loyd, Patricia Jane

    2012-01-01T23:59:59.000Z

    real option theory to irrigation dam investment analysis: an43, 2) 482–498. [40] World Commission on Dams (WCD), 2000.Dams and development: A new framework for decision- making.

  18. Gravity Recovery and Climate Experiment (GRACE) detection of water storage changes in the Three Gorges Reservoir of China and comparison with in situ measurements

    E-Print Network [OSTI]

    Wang, Xianwei; de Linage, Caroline; Famiglietti, James; Zender, Charles S

    2011-01-01T23:59:59.000Z

    with in situ reservoir volume change data, especially sinceGorges Reservoir, China using the SRTM DEM data, Int. J.in the GRACE data caused by the reservoir filling as W12502

  19. Saeltzer Dam Removal on Clear Creek 11 years later: An assessment of upstream channel changes since the dam's removal

    E-Print Network [OSTI]

    Simons, Crystal; Walker, Katelyn; Zimring, Mark

    2011-01-01T23:59:59.000Z

    Boulder BLDR Bedrock BDRK Dam Rubble DMRB Table B1. 2011pages. Brown, M. (n.d. ). Clear Creek—McCormick-Saeltzer DamRemoval: Dam removal re-opens spring run salmon habitat. US

  20. Design, Modeling, and Validation of a Flame Reformer for LNT...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Design, Modeling, and Validation of a Flame Reformer for LNT External Bypass Regeneration Design, Modeling, and Validation of a Flame Reformer for LNT External Bypass Regeneration...

  1. Effect of Nitrogen Additives on Flame Retardant Action of Tributyl...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nitrogen Additives on Flame Retardant Action of Tributyl Phosphate: Phosphorus – Nitrogen Synergism. Effect of Nitrogen Additives on Flame Retardant Action of Tributyl...

  2. Flame acceleration studies in the MINIFLAME facility

    SciTech Connect (OSTI)

    Tieszen, S.R.; Sherman, M.P.; Benedick, W.B.

    1989-07-01T23:59:59.000Z

    Flame acceleration and deflagration-to-detonation transition (DDT) studies have been conducted in a 19.4-cm high, 14.5-cm wide, and 2. 242-m long channel (MINIFLAME) that is a 1:12.6 scale model of the 136-m{sup 3} FLAME facility. Tests were conducted with two levels of hydrogen concentration -- 20% and 30%, with and without obstacles in the channel, and with three levels of transverse top venting -- 0%, 13%, and 50%. The flame acceleration results in MINIFLAME are qualitatively similar to those in FLAME; however, the small-scale results are more benign quantitatively. The results show that insufficient venting, 13% venting in this case, can promote flame acceleration due to turbulence produced by the flow through the vents in smooth channels. However, with obstacle-generated turbulence in the channel, 13% top venting was found to be beneficial. Flame acceleration resulting in DDT was shown to occur in as little as 35 liters of mixture. Comparison of the DDT data with obstacles in MINIFLAME and FLAME supports d/{lambda} scaling of DDT, where {lambda} is the detonation cell width of the mixture and d is the characteristic open diameter of the channel. In the MINIFLAME and FLAME tests, DDT occurred for d/{lambda} greater than approximately three. Comparison with other experiments shows that the value of d/{lambda} for DDT is not constant but depends on the obstacle type, spacing, and channel geometry. The comparison of MINIFLAME and FLAME experiments extends the use of d/{lambda} scaling to different geometries and larger scales than previous studies. Small-scale-model testing of flame acceleration and DDT with the same combustible mixture as the full-scale prototype underpredicts flame speeds, overpressures, and the possibility of DDT. 18 refs., 16 figs.

  3. Flame Interactions in Turbulent Premixed Twin V-flames

    E-Print Network [OSTI]

    Dunstan, T. D.; Swaminathan, N.; Bray, K. N. C.; Kingsbury, N. G.

    2013-01-16T23:59:59.000Z

    diminish with increasing turbulence intensity, and so it is unlikely that any significant influence remains within the regions of interest for the flames presented here. It should also be noted that no energy is added to the flow in the current implemen... . A flow-chart summary is given in Fig. 2, and an example of the procedure applied to two-dimensional test data is shown in Fig. 3. The AFE procedure used here comprises three principal stages: (1) the binarised c field data from two successive time...

  4. Guidewall demolition at Bonneville Dam

    SciTech Connect (OSTI)

    Marks, R.S. [Kiewit Pacific Co., Vancouver, WA (United States)

    1997-05-01T23:59:59.000Z

    Bonneville Dam, completed in 1938, included the smallest and busiest lock on the Columbia and Snake River Navigation System. To expedite barge traffic through this restriction, a new larger lock was designed and contracted by the U.S. Army Corp of Engineers. The project involved drill and shoot, alluvial gravel and rock excavation, dredging, rock support, structural concrete, and assorted demolitions. A large portion of the demolition work was the removal of the existing guidewall to allow barge traffic access to the new lock. Guidewall Demolition was completed using drill and shoot techniques and dredging the debris from the channel. This work involved unique challenges and innovative solutions to produce a successful result.

  5. Active control for turbulent premixed flame simulations

    SciTech Connect (OSTI)

    Bell, John B.; Day, Marcus S.; Grcar, Joseph F.; Lijewski, Michael J.

    2004-03-26T23:59:59.000Z

    Many turbulent premixed flames of practical interest are statistically stationary. They occur in combustors that have anchoring mechanisms to prevent blow-off and flashback. The stabilization devices often introduce a level of geometric complexity that is prohibitive for detailed computational studies of turbulent flame dynamics. As a result, typical detailed simulations are performed in simplified model configurations such as decaying isotropic turbulence or inflowing turbulence. In these configurations, the turbulence seen by the flame either decays or, in the latter case, increases as the flame accelerates toward the turbulent inflow. This limits the duration of the eddy evolutions experienced by the flame at a given level of turbulent intensity, so that statistically valid observations cannot be made. In this paper, we apply a feedback control to computationally stabilize an otherwise unstable turbulent premixed flame in two dimensions. For the simulations, we specify turbulent in flow conditions and dynamically adjust the integrated fueling rate to control the mean location of the flame in the domain. We outline the numerical procedure, and illustrate the behavior of the control algorithm. We use the simulations to study the propagation and the local chemical variability of turbulent flame chemistry.

  6. Correlation of flame speed with stretch in turbulent premixed methane/air flames

    SciTech Connect (OSTI)

    Chen, J.H.; Im, Hong G.

    1997-11-01T23:59:59.000Z

    In the flamelet approach of turbulent premixed combustion, the flames are modeled as a wrinkled surface whose propagation speed, termed the {open_quotes}displacement speed,{close_quotes} is prescribed in terms of the local flow field and flame geometry. Theoretical studies suggest a linear relation between the flame speed and stretch for small values of stretch, S{sub L}/S{sub L}{sup 0} = 1 - MaKa, where S{sub L}{sup 0} is the laminar flame speed, Ka = {kappa}{delta}{sub F}/S{sub L}{sup 0} is the nondimensional stretch or the Karlovitz number, and Ma = L/{delta}{sub F} is the Markstein number. The nominal flame thickness, {delta}{sub F}, is determined as the ratio of the mass diffusivity of the unburnt mixture to the laminar flame speed. Thus, the turbulent flame model relies on an accurate estimate of the Markstein number in specific flame configurations. Experimental measurement of flame speed and stretch in turbulent flames, however, is extremely difficult. As a result, measurement of flame speeds under strained flow fields has been made in simpler geometries, in which the effect of flame curvature is often omitted. In this study we present results of direct numerical simulations of unsteady turbulent flames with detailed methane/air chemistry, thereby providing an alternative method of obtaining flame structure and propagation statistics. The objective is to determine the correlation between the displacement speed and stretch over a broad range of Karlovitz numbers. The observed response of the displacement speed is then interpreted in terms of local tangential strain rate and curvature effects. 13 refs., 3 figs.

  7. Civil Engineering Explore the environmental impact of dams.

    E-Print Network [OSTI]

    Provancher, William

    Dams Civil Engineering Objective · Explore the environmental impact of dams. · Discuss the need for dams, and how environmental engineers mitigate some impacts. Standards and Objectives · Earth Systems humans' standard of living and environmental impacts. · The basic concept of constructing a dam

  8. DRAFT ENVIRONMENTAL ASSESSMENT1 PINE CREEK DAM, OKLAHOMA2

    E-Print Network [OSTI]

    US Army Corps of Engineers

    #12;#12;DRAFT ENVIRONMENTAL ASSESSMENT1 PINE CREEK DAM, OKLAHOMA2 DAM SAFETY MODIFICATION3 &4 Environmental Assessment Pine Creek Dam, Oklahoma Dam Safety Modification & Interim Risk Reduction Measure of Federal Regulations, Part 230, the Tulsa District has assessed the environmental impacts of modifications

  9. dam logic: qualitative reasoning about benthic macroinvertebrate responses

    E-Print Network [OSTI]

    Tullos, Desiree

    dam logic: qualitative reasoning about benthic macroinvertebrate responses to dam removal desiree reliability of biotic and abiotic indicators (e.g. responsiveness to dam removal, detectability, feasibility relationships "there appears to be a wide range of ecological responses to dam removal. It is therefore

  10. ImpactsofLarge Dams:agLobaL

    E-Print Network [OSTI]

    Chaudhuri, Sanjay

    #12;ImpactsofLarge Dams:agLobaL assessment Editors Cecilia Tortajada, Dogan Altinbilek, Asit K of the most controversial issues of the water sector in recent years has been the impacts of large dams and environmental costs of large dams far exceed their benefits, and that the era of construction of large dams

  11. Modelling of turbulent stratified flames

    E-Print Network [OSTI]

    Darbyshire, Oliver Richard

    ) shows data with a negative correlation, (b) shows data with no correlation and (c) shows data with a positive correlation. . . . . . . . . 44 3.3 Flow chart of the SIMPLE algorithm. . . . . . . . . . . . . . . . . . . . . 50 3.4 Schematic of the V... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 4.1 Comparison of predicted and measured velocities (m/s) and turbulence kinetic energy (m2/s2) for the cold flow ORACLES experiment. . . . . . 64 4.2 Comparison of cold flow results for the V-flame case. Mean axial velocity is shown on the left...

  12. Green River Locks and Dams 3, 4, 5, 6 and Barren River Lock and Dam 1 Disposition, Kentucky

    E-Print Network [OSTI]

    US Army Corps of Engineers

    until 1981 when it was closed due to declining boat traffic. Since the failure of Green River Dam 4 by the dams and the impacts if the pool were to be lost, either by demolition or failure of the lock andGreen River Locks and Dams 3, 4, 5, 6 and Barren River Lock and Dam 1 Disposition, Kentucky 16

  13. EVOLVING EXPECTATIONS OF DAM REMOVAL OUTCOMES: DOWNSTREAM GEOMORPHIC EFFECTS FOLLOWING REMOVAL OF A SMALL, GRAVEL-FILLED DAM1

    E-Print Network [OSTI]

    Tullos, Desiree

    EVOLVING EXPECTATIONS OF DAM REMOVAL OUTCOMES: DOWNSTREAM GEOMORPHIC EFFECTS FOLLOWING REMOVAL OF A SMALL, GRAVEL-FILLED DAM1 Kelly Kibler, Desiree Tullos, and Mathias Kondolf 2 ABSTRACT: Dam removal is a promising river restoration technique, particularly for the vast number of rivers impounded by small dams

  14. Perspectives on Dam Removal: York Creek Dam and the Water Framework Directive

    E-Print Network [OSTI]

    Lawrence, Justin E; Pollak, Josh D; Richmond, Sarah F

    2008-01-01T23:59:59.000Z

    supply, flood control, hydropower, and recreation. However,as changes induced by hydropower, flood control, or waterFERC requires private hydropower dams to provide “equal

  15. Dams, Mills, and Electric Power (Missouri)

    Broader source: Energy.gov [DOE]

    The Water Resources Center of the Missouri Department of Natural Resources is responsible for implementing regulations pertaining to dam and reservoir safety. Any person or corporation may erect a...

  16. Dam Control and Safety Act (West Virginia)

    Broader source: Energy.gov [DOE]

    This law grants authority to the secretary of the Department of Environmental Protection to control and exercise regulatory jurisdiction over dams as indicated in the subsections of the law. This...

  17. Dam Safety and Encroachments Act (Pennsylvania)

    Broader source: Energy.gov [DOE]

    This act sets the standards and criteria for the siting and design of dams, water obstructions and encroachments considering both existing and projected conditions. It requires operational plans to...

  18. Safe Dams Act of 1972 (Tennessee)

    Broader source: Energy.gov [DOE]

    The Safe Dams Act of 1973 (SDA) gives the Commissioner of the Department of Environment and Conservation the power to issue certificates authorizing the construction, alteration, or operation of a...

  19. Processes affecting the spatial and temporal variability of methane in a temperate dammed river system

    E-Print Network [OSTI]

    Bilsley, Nicole A.

    2012-01-01T23:59:59.000Z

    emissions from large dams as renewable energy resources: Areservoir (Brazil’s Tucuruí Dam) and the energy policyemissions from hydroelectric dams: controversies provide a

  20. Aromatics oxidation and soot formation in flames

    SciTech Connect (OSTI)

    Howard, J.B.; Pope, C.J.; Shandross, R.A.; Yadav, T. [Massachusetts Institute of Technology, Cambridge (United States)

    1993-12-01T23:59:59.000Z

    This project is concerned with the kinetics and mechanisms of aromatics oxidation and soot and fullerenes formation in flames. The scope includes detailed measurements of profiles of stable and radical species concentrations in low-pressure one-dimensional premixed flames. Intermediate species identifications and mole fractions, fluxes, and net reaction rates calculated from the measured profiles are used to test postulated reaction mechanisms. Particular objectives are to identify and to determine or confirm rate constants for the main benzene oxidation reactions in flames, and to characterize fullerenes and their formation mechanisms and kinetics.

  1. atomic-absorption flame photometry: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    to modeling thermonuclear flames CiteSeer Summary: Turbulence-flame interactions of thermonuclear fusion flames occurring in Type Ia Supernovae were studied by means of...

  2. Flame Spectral Analysis for Boiler Control

    E-Print Network [OSTI]

    Metcalfe, C. I.; Cole, W. E.; Batra, S. K.

    range from the flames and using these measurements to determine the burner operating conditions. Two prototype instruments have been installed on package boilers at a Con Edison powerplant and Polaroid facility, and their performance has been evaluated...

  3. Theory of DDT in unconfined flames

    E-Print Network [OSTI]

    Khokhlov, A M; Wheeler, J C; Wheeler, J Craig

    1996-01-01T23:59:59.000Z

    This paper outlines a theoretical approach for predicting the onset of detonation in unconfined turbulent flames which is relevant both to problems of terrestrial combustion and to thermonuclear burning in Type Ia supernovae. Two basic assumuptions are made: 1) the gradient mechanism is the inherent mechanism that leads to DDT in unconfined conditions, and 2) the sole mechanism for preparing the gradient in induction time is by turbulent mixing and local flame quenching. The criterion for DDT is derived in terms of the one-dimensional detonation wave thickness, the laminar flame speed, and the laminar flame thickness in the reactive gas. This approach gives a lower-bound criterion for DDT for conditions where shock preheating, wall effects, and interactions with obstacles are absent. Regions in parameter space where unconfined DDT can and cannot occur are determined. A subsequent paper will address these issues specifically in the astrophysical context.

  4. Theory of DDT in Unconfined Flames

    E-Print Network [OSTI]

    A. M. Khokhlov; E. S. Oran; J. Craig Wheeler

    1996-05-15T23:59:59.000Z

    This paper outlines a theoretical approach for predicting the onset of detonation in unconfined turbulent flames which is relevant both to problems of terrestrial combustion and to thermonuclear burning in Type Ia supernovae. Two basic assumuptions are made: 1) the gradient mechanism is the inherent mechanism that leads to DDT in unconfined conditions, and 2) the sole mechanism for preparing the gradient in induction time is by turbulent mixing and local flame quenching. The criterion for DDT is derived in terms of the one-dimensional detonation wave thickness, the laminar flame speed, and the laminar flame thickness in the reactive gas. This approach gives a lower-bound criterion for DDT for conditions where shock preheating, wall effects, and interactions with obstacles are absent. Regions in parameter space where unconfined DDT can and cannot occur are determined. A subsequent paper will address these issues specifically in the astrophysical context.

  5. Enol Intermediates Unexpectedly Found in Flames

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at ALS Chemical Dynamics Beamline 9.0.2. In the apparatus, premixed reagent gases enter the flame chamber through the porous flat face of a burner that translates...

  6. Characterisation of an oxy-coal flame through digital imaging

    SciTech Connect (OSTI)

    Smart, John; Riley, Gerry [RWE npower plc, Windmill Hill Business Park, Whitehill Way, Swindon SN5 6PB (United Kingdom); Lu, Gang; Yan, Yong [Instrumentation, Control and Embedded Systems Research Group, School of Engineering and Digital Arts, University of Kent, Canterbury, Kent CT2 7NT (United Kingdom)

    2010-06-15T23:59:59.000Z

    This paper presents investigations into the impact of oxy-fuel combustion on flame characteristics through the application of digital imaging and image processing techniques. The characteristic parameters of the flame are derived from flame images that are captured using a vision-based flame monitoring system. Experiments were carried out on a 0.5 MW{sub th} coal combustion test facility. Different flue gas recycle ratios and furnace oxygen levels were created for two different coals. The characteristics of the flame and the correlation between the measured flame parameters and corresponding combustion conditions are described and discussed. The results show that the flame temperature decreases with the recycle ratio for both test coals, suggesting that the flame temperature is effectively controlled by the flue gas recycle ratio. The presence of high levels of CO{sub 2} at high flue gas recycle ratios may result in delayed combustion and thus has a detrimental effect on the flame stability. (author)

  7. NO concentration imaging in turbulent nonpremixed flames

    SciTech Connect (OSTI)

    Schefer, R.W. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    The importance of NO as a pollutant species is well known. An understanding of the formation characteristics of NO in turbulent hydrocarbon flames is important to both the desired reduction of pollutant emissions and the validation of proposed models for turbulent reacting flows. Of particular interest is the relationship between NO formation and the local flame zone, in which the fuel is oxidized and primary heat release occurs. Planar imaging of NO provides the multipoint statistics needed to relate NO formation to the both the flame zone and the local turbulence characteristics. Planar imaging of NO has been demonstrated in turbulent flames where NO was seeded into the flow at high concentrations (2000 ppm) to determine the gas temperature distribution. The NO concentrations in these experiments were significantly higher than those expected in typical hydrocarbon-air flames, which require a much lower detectability limit for NO measurements. An imaging technique based on laser-induced fluorescence with sufficient sensitivity to study the NO formation mechanism in the stabilization region of turbulent lifted-jet methane flames.

  8. On the critical flame radius and minimum ignition energy for spherical flame initiation

    E-Print Network [OSTI]

    Ju, Yiguang

    , methane, and propane). The emphasis is placed on investigating the critical flame radius controlling to the cube of the critical flame radius. Furthermore, preferential diffusion of heat and mass (i.e. the Lewis igni- tion energy. Ã? 2010 The Combustion Institute. Published by Elsevier Inc. All rights reserved

  9. Channel response to Dam Removal, Clear Creek, California

    E-Print Network [OSTI]

    Miller, Peter; Vizcaino, Pilar

    2004-01-01T23:59:59.000Z

    to Dam Removal, Clear Creek, California Peter Miller and9, 2004 Abstract Clear Creek drains 720 km 2 , joining the2002) Saeltzer Dam on Clear Creek was a good candidate for

  10. Power benefits of the lower Snake River dams - FACT SHEET

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    I n the 1960s and early 1970s, the federal government built four large dams on the Snake River. This is the last set of major dams to have been built in the Federal Columbia River...

  11. Lac Courte Oreilles Hydro Dam Assessment

    SciTech Connect (OSTI)

    Weaver, Jason [Lac Courte Oreilles; Meyers, Amy [Kiser Hydro

    2014-12-31T23:59:59.000Z

    The main objective of this project was to investigate upgrading the existing hydro power generating system at the Winter Dam. The tribe would like to produce more energy and receive a fair market power purchase agreement so the dam is no longer a drain on our budget but a contributor to our economy. We contracted Kiser Hydro, LLC Engineering for this project and received an engineering report that includes options for producing more energy with cost effective upgrades to the existing turbines. Included in this project was a negotiation of energy price sales negotiations.

  12. Student Competition: Siting Potential Dams at Camp Del Webb, Utah

    E-Print Network [OSTI]

    Wamser, William Kyle

    2007-11-14T23:59:59.000Z

    Siting Potential Dams at Camp Del Webb, Utah Presented By: Kyle Wamser Problem ? Camp Del Webb is Lacking an Onsite Lake ? High Adventure Bases generally need aquatics ? Large lake nearby, but transportation is required ? Possible Solution... hillshade ? Finding Possible Lake Locations ? Added three potential dam sites ? Calculated watersheds ? Extended dams through terrain to prevent runoff on the sides ? Calculated watershed dam elevation, which identified lakes Results...

  13. ORIGINAL ARTICLE Big dams and salmon evolution: changes in thermal

    E-Print Network [OSTI]

    Angilletta, Michael

    ORIGINAL ARTICLE Big dams and salmon evolution: changes in thermal regimes and their potential (Oncorhynchus spp.) across portions of their natural range, dams have arguably played a major role in many locations (NRC 1996; Lichatowich 1999; Ruckelshaus et al. 2002). Large dams (>15 m tall)­ designed

  14. MURTHY, MURTY AND RAGHUPATHY Designing Earth Dams Optimally

    E-Print Network [OSTI]

    Murty, Katta G.

    [ 91 ] MURTHY, MURTY AND RAGHUPATHY Designing Earth Dams Optimally G S R Murthy1 , Katta G Murty2 HES Infra Limited, Hyderabad, India Abstract : Engineering design of an earth dam is a crucial issue, it aims at formulating the problem of designing earth dams as an optimization problem. The problem

  15. GEOSYNTHETIC DAM LINING SYSTEMS By: Christine T. Weber1

    E-Print Network [OSTI]

    Zornberg, Jorge G.

    GEOSYNTHETIC DAM LINING SYSTEMS By: Christine T. Weber1 and Jorge Zornberg, Advisor Abstract: The overall goal of this project is to contribute towards the use of geosynthetics in the design of dams geomembrane and composite liners under conditions representative of dams. There has been previous work done

  16. FLOOD WARNING SYSTEM BRISBANE RIVER ABOVE WIVENHOE DAM

    E-Print Network [OSTI]

    Greenslade, Diana

    FLOOD WARNING SYSTEM for the BRISBANE RIVER ABOVE WIVENHOE DAM This brochure describes the flood above Wivenhoe Dam. It includes reference information which will be useful for understanding Flood above Wivenhoe Dam drains an area of approximately 7,000 square kilometres. The Brisbane River rises

  17. FLOOD WARNING SYSTEM BRISBANE RIVER BELOW WIVENHOE DAM

    E-Print Network [OSTI]

    Greenslade, Diana

    FLOOD WARNING SYSTEM for the BRISBANE RIVER BELOW WIVENHOE DAM TO BRISBANE CITY This brochure for the Brisbane River below Wivenhoe Dam to Brisbane City. It includes reference information which will be useful kilometres of which about half is below Wivenhoe Dam. The Lockyer-Laidley Valley drains into the Brisbane

  18. Dam-Breach Flood Wave Propagation Using Dimensionless Parameters

    E-Print Network [OSTI]

    Ponce, V. Miguel

    Dam-Breach Flood Wave Propagation Using Dimensionless Parameters Victor M. Ponce, M.ASCE1 ; Ahmad to study the sensitivity of dam-breach flood waves to breach-outflow hydrograph volume, peak discharge the channel. A dam-breach Froude number is defined to enable analysis through a wide range of site and flow

  19. MFR PAPER 1222 Effects of Dams on Pacific Salmon

    E-Print Network [OSTI]

    MFR PAPER 1222 Effects of Dams on Pacific Salmon and Steelhead Trout GERALD B. COLLINS INTRODUCTION on the survival of salmon than the construction of dams. The watershed of the Columbia River presents a critical illustration of the effects of dams on salmon, reflecting events in progress in the entire Pacific Northwest

  20. Ultraviolet imaging of hydrogen flames

    SciTech Connect (OSTI)

    Yates, G.J.; Wilke, M.; King, N.

    1988-01-01T23:59:59.000Z

    We have assembled an ultraviolet-sensitive intensified camera for observing hydrogen combustion by imaging the OH, A/sup 2/..sigma.. - X/sup 2//Pi/ bandhead emissions near 309 nm. The camera consists of a quartz and CaF achromat lense-coupled to an ultraviolet image intensifier which is in turn fiber-coupled to a focus projection scan (FPS) vidicon. The emission band is selected with interference filters which serve to discriminate against background. The camera provides optical gain of 100 to 1000 and is capable of being shuttered at nanosecond speeds and of being framed at over 600 frames per second. We present data from observations of test flames in air at standard RS-170 video rates with varying background conditions. Enhanced images using background subtraction are presented. Finally, we discuss the use of polarizaton effects to further discrimination against sky background. This work began as a feasibility study to investigate ultraviolet technology to detect hydrogen fires for the NASA space program. 6 refs., 7 figs, 2 tabs.

  1. Chapter 13 Water Resources Hoover Dam

    E-Print Network [OSTI]

    Pan, Feifei

    management Water shortage linked to food supply Learning Objectives #12; The global water cycleChapter 13 Water Resources #12;Hoover Dam #12;The Colorado River Basin Population growth Urbanization Climate change #12; Water cycle Water use Surface water and groundwater processes Water

  2. Aromatics oxidation and soot formation in flames

    SciTech Connect (OSTI)

    Howard, J.B.; Pope, C.J.; Shandross, R.A.; Yadav, T.

    1993-04-01T23:59:59.000Z

    This project is concerned with the kinetics and mechanisms of aromatics oxidation and soot and fullerenes formation in flames. The scope includes detailed measurements of profiles of stable and radical species concentrations in low-pressure one-dimensional premixed flames. Intermediate species identifications and mole fractions, fluxes, and net reaction rates calculated from the measured profiles are used to test postulated reaction mechanisms. Particular objectives are to identify, and to confirm or determine rate constants for, the main benzene oxidation reactions in flames, and to characterize soot and fullerenes and their formation mechanisms and kinetics. Stable and radical species profiles in the aromatics oxidation study are measured using molecular beam sampling with on-line mass spectrometry. The rate of soot formation measured by conventional optical techniques is found to support the hypotheses that particle inception occurs through reactive coagulation of high molecular weight PAH in competition with destruction by OHattack, and that the subsequent growth of the soot mass occurs through addition reactions of PAH and C[sub 2]H[sub 2] with the soot particles. During the first year of this reporting period, fullerenes C[sub 60] and C[sub 70] in substantial quantities were found in the flames being studied. The fullerenes were recovered, purified and spectroscopically identified. The yields of C[sub 60] and C[sub 70] were then determined over ranges of conditions in low-pressure premixed flames of benzene and oxygen.

  3. Paper # A02 Topic: Laminar Flames US Combustion Meeting

    E-Print Network [OSTI]

    Seitzman, Jerry M.

    been focused on synthetic fuel gas (syngas) combustion. Syngas is derived from coal through of the flame speeds of syngas mixtures.3-5 For example, stretch corrected laminar flame speed measurements

  4. Investigating the Flame Microstructure in Type Ia Supernovae

    E-Print Network [OSTI]

    Roepke, F K; Niemeyer, J C

    2002-01-01T23:59:59.000Z

    We present a numerical model to study the behavior of thermonuclear flames in the discontinuity approximation. This model is applied to investigate the Landau-Darrieus instability under conditions found in Type Ia supernova explosions of Chandrasekhar mass white dwarfs. This is a first step to explore the flame microstructure in these events. The model reproduces Landau's linearized stability analysis in early stages of the flame evolution and the stabilization in a cellular flame structure in the nonlinear stage.

  5. Investigating the Flame Microstructure in Type Ia Supernovae

    E-Print Network [OSTI]

    F. K. Roepke; W. Hillebrandt; J. C. Niemeyer

    2002-04-02T23:59:59.000Z

    We present a numerical model to study the behavior of thermonuclear flames in the discontinuity approximation. This model is applied to investigate the Landau-Darrieus instability under conditions found in Type Ia supernova explosions of Chandrasekhar mass white dwarfs. This is a first step to explore the flame microstructure in these events. The model reproduces Landau's linearized stability analysis in early stages of the flame evolution and the stabilization in a cellular flame structure in the nonlinear stage.

  6. Pentan isomers compound flame front structure

    SciTech Connect (OSTI)

    Mansurov, Z.A.; Mironenko, A.W.; Bodikov, D.U.; Rachmetkaliev, K.N. [Kazakh Al-Farabi State National Univ., Almaty (Kazakhstan)

    1995-08-13T23:59:59.000Z

    The fuels (hexane, pentane, diethyl ether) and conditions investigated in this study are relevant to engine knock in spark- ignition engines. A review is provided of the field of low temperature hydrocarbon oxidation. Studies were made of radical and stable intermediate distribution in the front of cool flames: Maximum concentrations of H atoms and peroxy radicals were observed in the luminous zone of the cool flame front. Peroxy radicals appear before the luminous zone at 430 K due to diffusion. H atoms were found in cool flames of butane and hexane. H atoms diffuses from the luminous zone to the side of the fresh mixture, and they penetrate into the fresh mixture to a small depth. Extension of action sphear of peroxy radicals in the fresh mixture is much greater than that of H atoms due to their small activity and high concentrations.

  7. FLAME SURFACE DENSITIES IN PREMIXED COMBUSTION AT MEDIUM TO HIGH

    E-Print Network [OSTI]

    Gülder, �mer L.

    premixed combustion diagrams. Small-scale transport of heat and species may be more important and chemistryFLAME SURFACE DENSITIES IN PREMIXED COMBUSTION AT MEDIUM TO HIGH TURBULENCE INTENSITIES O¨ MER L in turbulent premixed propane= air flames were determined experimentally. The instantaneous flame fronts were

  8. Flame front tracking by laser induced fluorescence spectroscopy and advanced

    E-Print Network [OSTI]

    Hamarneh, Ghassan

    surface characteristics in turbulent premixed propane/air combustion," Combustion and Flame 120(4), 407 References and links 1. J. Warnatz, U. Maas, and R.W. Dibble, Combustion - physical and chemical fundamentals, "Characterization of flame front surfaces in turbulent premixed methane/air combustion," Combustion and Flame 101

  9. Bull Trout Population Assessment in the Columbia River Gorge : Annual Report 2000.

    SciTech Connect (OSTI)

    Byrne, Jim; McPeak, Ron

    2001-02-01T23:59:59.000Z

    We summarized existing knowledge regarding the known distribution of bull trout (Salvelinus confluentus) across four sub-basins in the Columbia River Gorge in Washington. The Wind River, Little White Salmon River, White Salmon River, and the Klickitat River sub-basins were analyzed. Cold water is essential to the survival, spawning, and rearing of bull trout. We analyzed existing temperature data, installed Onset temperature loggers in the areas of the four sub-basins where data was not available, and determined that mean daily water temperatures were <15 C and appropriate for spawning and rearing of bull trout. We snorkel surveyed more than 74 km (46.25 mi.) of rivers and streams in the four sub-basins (13.8 km at night and 60.2 km during the day) and found that night snorkeling was superior to day snorkeling for locating bull trout. Surveys incorporated the Draft Interim Protocol for Determining Bull Trout Presence (Peterson et al. In Press). However, due to access and safety issues, we were unable to randomly select sample sites nor use block nets as recommended. Additionally, we also implemented the Bull Trout/Dolly Varden sampling methodology described in Bonar et al. (1997). No bull trout were found in the Wind River, Little White Salmon, or White Salmon River sub-basins. We found bull trout in the West Fork Klickitat drainage of the Klickitat River Sub-basin. Bull trout averaged 6.7 fish/100m{sup 2} in Trappers Creek, 2.6 fish/100m{sup 2} on Clearwater Creek, and 0.4 fish/100m{sup 2} in Little Muddy Creek. Bull trout was the only species of salmonid encountered in Trappers Creek and dominated in Clearwater Creek. Little Muddy Creek was the only creek where bull trout and introduced brook trout occurred together. We found bull trout only at night and typically in low flow regimes. A single fish, believed to be a bull trout x brook trout hybrid, was observed in the Little Muddy Creek. Additional surveys are needed in the West Fork Klickitat and mainstem Klickitat to determine the distribution of bull trout throughout the drainage and to determine the extent of hybridization with brook trout.

  10. Computatonal and experimental study of laminar flames

    SciTech Connect (OSTI)

    Smooke, M.D.; Long, M.B. [Yale Univ., New Haven, CT (United States)

    1993-12-01T23:59:59.000Z

    This research has centered on an investigation of the effects of complex chemistry and detailed transport on the structure and extinction of hydrocarbon flames in counterflow, cylindrical and coflowing axisymmetric configurations. The authors have pursued both computational and experimental aspects of the research in parallel. The computational work has focused on the application of accurate and efficient numerical methods for the solution of the one and two-dimensional nonlinear boundary value problems describing the various reacting systems. Detailed experimental measurements were performed on axisymmetric coflow flames using two-dimensional imaging techniques. In particular, spontaneous Raman scattering and laser induced fluorescence were used to measure the temperature, major and minor species profiles.

  11. The effect of flame structure on soot formation and transport in turbulent nonpremixed flames using direct numerical simulation

    SciTech Connect (OSTI)

    Lignell, David O. [Department of Chemical Engineering, University of Utah, Salt Lake City, UT 84098 (United States); Reacting Flow Research Department, Combustion Research Facility, Sandia National Laboratories, Livermore, CA 94551 (United States); Chen, Jacqueline H. [Reacting Flow Research Department, Combustion Research Facility, Sandia National Laboratories, Livermore, CA 94551 (United States); Smith, Philip J. [Department of Chemical Engineering, University of Utah, Salt Lake City, UT 84098 (United States); Lu, Tianfeng; Law, Chung K. [Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08540 (United States)

    2007-10-15T23:59:59.000Z

    Direct numerical simulations of a two-dimensional, nonpremixed, sooting ethylene flame are performed to examine the effects of soot-flame interactions and transport in an unsteady configuration. A 15-step, 19-species (with 10 quasi-steady species) chemical mechanism was used for gas chemistry, with a two-moment, four-step, semiempirical soot model. Flame curvature is shown to result in flames that move, relative to the fluid, either toward or away from rich soot formation regions, resulting in soot being essentially convected into or away from the flame. This relative motion of flame and soot results in a wide spread of soot in the mixture fraction coordinate. In regions where the center of curvature of the flame is in the fuel stream, the flame motion is toward the fuel and soot is located near the flame at high temperature and hence has higher reaction rates and radiative heat fluxes. Soot-flame breakthrough is also observed in these regions. Fluid convection and flame displacement velocity relative to fluid convection are of similar magnitudes while thermophoretic diffusion is 5-10 times lower. These results emphasize the importance of both unsteady and multidimensional effects on soot formation and transport in turbulent flames. (author)

  12. COMBUSTION AND FLAME 24, 27-34 (1975) 27 Flame Emission Studies of Ozone with Metal Alkyls

    E-Print Network [OSTI]

    Zare, Richard N.

    COMBUSTION AND FLAME 24, 27-34 (1975) 27 Flame Emission Studies of Ozone with Metal Alkyls: Zn (CH3 of combustion. Premixed [2, 3] anddiffusion [4] flames of metal alkyl compounds have been carried out to deter- tageous to study the combustion of polyatomic molecules under single-collision conditions, i

  13. Rayleigh-Taylor Unstable Flames -- Fast or Faster?

    E-Print Network [OSTI]

    Hicks, E P

    2015-01-01T23:59:59.000Z

    Rayleigh-Taylor (RT) unstable flames play a key role in the explosions of Type Ia supernovae. However, the dynamics of these flames is still not well-understood. RT unstable flames are affected by both the RT instability of the flame front and by RT-generated turbulence. The coexistence of these factors complicates the choice of flame speed subgrid models for full-star Type Ia simulations. Both processes can stretch and wrinkle the flame surface, increasing its area and, therefore, the burning rate. In past research, subgrid models have been based on either the RT instability or turbulence setting the flame speed. We evaluate both models, checking their assumptions and their ability to correctly predict the turbulent flame speed. Specifically, we analyze a large parameter study of 3D direct numerical simulations of RT unstable model flames. This study varies both the simulation domain width and the gravity in order to probe a wide range of flame behaviors. We show that RT unstable flames are different from tr...

  14. Power-law wrinkling turbulence-flame interaction model for astrophysical flames

    SciTech Connect (OSTI)

    Jackson, Aaron P. [Laboratories for Computational Physics and Fluid Dynamics, Naval Research Laboratory, Washington, DC (United States); Townsley, Dean M. [Department of Physics and Astronomy, The University of Alabama, Tuscaloosa, AL (United States); Calder, Alan C. [Department of Physics and Astronomy, The State University of New York - Stony Brook, Stony Brook, NY (United States)

    2014-04-01T23:59:59.000Z

    We extend a model for turbulence-flame interactions (TFI) to consider astrophysical flames with a particular focus on combustion in Type Ia supernovae. The inertial range of the turbulent cascade is nearly always under-resolved in simulations of astrophysical flows, requiring the use of a model in order to quantify the effects of subgrid-scale wrinkling of the flame surface. We provide implementation details to extend a well-tested TFI model to low-Prandtl number flames for use in the compressible hydrodynamics code FLASH. A local, instantaneous measure of the turbulent velocity is calibrated for FLASH and verification tests are performed. Particular care is taken to consider the relation between the subgrid rms turbulent velocity and the turbulent flame speed, especially for high-intensity turbulence where the turbulent flame speed is not expected to scale with the turbulent velocity. Finally, we explore the impact of different TFI models in full-star, three-dimensional simulations of Type Ia supernovae.

  15. Radiation Heat Transfer in Particle-Laden Gaseous Flame: Flame Acceleration and Triggering Detonation

    E-Print Network [OSTI]

    Liberman, M A; Kiverin, A D

    2015-01-01T23:59:59.000Z

    In this study we examine influence of the radiation heat transfer on the combustion regimes in the mixture, formed by suspension of fine inert particles in hydrogen gas. The gaseous phase is assumed to be transparent for the thermal radiation, while the radiant heat absorbed by the particles is then lost by conduction to the surrounding gas. The particles and gas ahead of the flame is assumed to be heated by radiation from the original flame. It is shown that the maximum temperature increase due to the radiation preheating becomes larger for a flame with lower velocity. For a flame with small enough velocity temperature of the radiation preheating may exceed the crossover temperature, so that the radiation heat transfer may become a dominant mechanism of the flame propagation. In the case of non-uniform distribution of particles, the temperature gradient formed due to the radiation preheating can initiate either deflagration or detonation ahead of the original flame via the Zel'dovich's gradient mechanism. Th...

  16. Environmentally Benign Flame Retardant Nanocoatings for Fabric

    E-Print Network [OSTI]

    Li, Yu-Chin

    2012-07-16T23:59:59.000Z

    nanocomposites in an effort to produce more flame-retardant coatings. Laponite and montmorillonite (MMT) clay were paired with branched poly(ethylenimine) to create thin film assemblies that can be tailored by changing pH and concentration of aqueous deposition...

  17. Environmentally Benign Flame Retardant Nanocoatings for Fabric 

    E-Print Network [OSTI]

    Li, Yu-Chin

    2012-07-16T23:59:59.000Z

    nanocomposites in an effort to produce more flame-retardant coatings. Laponite and montmorillonite (MMT) clay were paired with branched poly(ethylenimine) to create thin film assemblies that can be tailored by changing pH and concentration of aqueous deposition...

  18. AIAA 010189 Ignition and Flame Studies for

    E-Print Network [OSTI]

    Liu, Feng

    beyond the turbine blade material limit. Sirignano and Liu1,2 show by thermodynamic analysis-dimensional diffusion flame in a transonic flow with large pressure gradients typical of conditions in a turbine passage-to-weight ratio and to widen the range of engine operation. Since the flow in a turbine passage is accelerating

  19. Flame Propagation of Butanol Isomers/Air Mixtures

    SciTech Connect (OSTI)

    Veloo, Peter S.; Egolfopoulos, Fokion N.

    2011-01-01T23:59:59.000Z

    An experimental and computational study was conducted on the propagation of flames of saturated butanol isomers. The experiments were performed in the counterflow configuration under atmospheric pressure, unburned mixture temperature of 343 K, and for a wide range of equivalence ratios. The experiments were simulated using a recent kinetic model for the four isomers of butanol. Results indicate that n-butanol/air flames propagate somewhat faster than both sec-butanol/air and iso-butanol/air flames, and that tert-butanol/air flames propagate notably slower compared to the other three isomers. Reaction path analysis of tert-butanol/air flames revealed that iso-butene is a major intermediate, which subsequently reacts to form the resonantly stable iso-butenyl radical retarding thus the overall reactivity of tert-butanol/air flames relatively to the other three isomers. Through sensitivity analysis, it was determined that the mass burning rates of sec-butanol/air and iso-butanol/air flames are sensitive largely to hydrogen, carbon monoxide, and C{sub 1}–C{sub 2} hydrocarbon kinetics and not to fuel-specific reactions similarly to n-butanol/air flames. However, for tert-butanol/air flames notable sensitivity to fuel-specific reactions exists. While the numerical results predicted closely the experimental data for n-butanol/air and sec-butanol/air flames, they overpredicted and underpredicted the laminar flame speeds for iso-butanol/air and tert-butanol/air flames respectively. It was demonstrated further that the underprediction of the laminar flame speeds of tert-butanol/air flames by the model was most likely due to deficiencies of the C{sub 4}-alkene kinetics.

  20. Intl. J. River Basin Management Vol. 7, No. 4 (2009), pp. 423431 2009 IAHR, INBO & IAHS

    E-Print Network [OSTI]

    Shankman, David

    2009-01-01T23:59:59.000Z

    Science Observation, (ITC) P.O. Box 6,700 AA, Enschede, The Netherlands. Current Address: International-Gorges Dam, which was intended for flood-control. The Three-Gorges Dam can be used to hold back floodwater

  1. Dynamic model failure tests of dam structures Dalian University of Technology, Dalian 116024, China

    E-Print Network [OSTI]

    Spencer Jr., B.F.

    Dynamic model failure tests of dam structures Gao Lin Dalian University of Technology, Dalian failure tests of a number of concrete gravity dams, concrete arch dams and embankment dams have been index for the safety assessment of concrete dams and is predicted through dynamic model failure tests

  2. Department of Mechanical Engineering Spring 2011 General Motors 2 Variable Height Vehicle Air Dam

    E-Print Network [OSTI]

    Demirel, Melik C.

    Vehicle Air Dam Overview The fundamental issue with fixed air dams is the bottom edge of the dam needs to be high enough to meet defined vehicle ground clearance and front approach angle criteria. Air dams must a solution to this problem by designing an variable height vehicle air dam. Objectives Our mission

  3. Dams have played an important role in human development throughout the world for thousands

    E-Print Network [OSTI]

    Dams have played an important role in human development throughout the world for thousands of years dams (>15 m in height) and an estimated 800 000 small dams had been built worldwide (WCD 2000 than 22 000 large dams (but only 22 before 1949), China is the largest dam-building country; by way

  4. [Mechanism and enhancement of flame stabilization]. [Annual report, 1993--1994

    SciTech Connect (OSTI)

    Not Available

    1993-11-01T23:59:59.000Z

    During this period, the following projects were completed: structural invariance of purely strained planar premixed flames, thermophoretic effects on seeding particles in LDV measurements, analysis of geometry of Bunsen flames, flame propagation in periodic flow fields, adiabatic flame stabilization, and chain-thermal theory of flame extinction.

  5. Flame quality monitor system for fixed firing rate oil burners

    DOE Patents [OSTI]

    Butcher, Thomas A. (Pt. Jefferson, NY); Cerniglia, Philip (Moriches, NY)

    1992-01-01T23:59:59.000Z

    A method and apparatus for determining and indicating the flame quality, or efficiency of the air-fuel ratio, in a fixed firing rate heating unit, such as an oil burning furnace, is provided. When the flame brightness falls outside a preset range, the flame quality, or excess air, has changed to the point that the unit should be serviced. The flame quality indicator output is in the form of lights mounted on the front of the unit. A green light indicates that the flame is about in the same condition as when the burner was last serviced. A red light indicates a flame which is either too rich or too lean, and that servicing of the burner is required. At the end of each firing cycle, the flame quality indicator goes into a hold mode which is in effect during the period that the burner remains off. A yellow or amber light indicates that the burner is in the hold mode. In this mode, the flame quality lights indicate the flame condition immediately before the burner turned off. Thus the unit can be viewed when it is off, and the flame condition at the end of the previous firing cycle can be observed.

  6. Title 33 USC 401 Construction of Bridges, Causeways, Dams or...

    Open Energy Info (EERE)

    Reference LibraryAdd to library Legal Document- StatuteStatute: Title 33 USC 401 Construction of Bridges, Causeways, Dams or Dikes Generally; ExemptionsLegal Abstract Section...

  7. analysis model dam: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Medical Image Analysis Erik B. Dam Biology and Medicine Websites Summary: - mentation program, the possible performance improvement due to non-linear diffusion is not unlimited,...

  8. arch dams including: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Websites Summary: insight into the gamut of shallow water waves, including kinematic, diffusion, dynamic, and gravity wavesDam-Breach Flood Wave Propagation Using...

  9. Company shelves dam to avoid agency's conservation edict

    SciTech Connect (OSTI)

    Springer, N.

    1985-01-06T23:59:59.000Z

    The Great Northern Paper Co. is shelving plans to build a hydroelectric dam because of two stipulations by the Maine Land Use Regulation Commission (LURC) requiring the company to fund a comprehensive energy audit of several mills in the area and submit a plan for modernizing outdated paper producing machines. Critics of the dam contend that in-plant conservation would free up more power than the dam would produce. The basis for this was an internal memo citing possible large amounts of wasted energy from motors that need rewinding. Although the company is retaining the option to build, the future of the Big A dam is uncertain.

  10. Horse and Libby dams. VarQ was made permanent at Libby and Hun-gry Horse dams by 2009, after an extensive Environmental

    E-Print Network [OSTI]

    VarQ Horse and Libby dams. VarQ was made permanent at Libby and Hun- gry Horse dams by 2009, afterQ providedecosystembenefitswhilemaintainingthesameFRMbenefits as under standard FRM. How Does VarQ Impact Canada? Above Libby Dam, both U of the border. Below Libby Dam, both U.S. and Canadian fish populations benefit from river flows that more

  11. Potential Geomorphic and Ecological Impacts of Marmot Dam Removal, Sandy River, OR

    E-Print Network [OSTI]

    Marmot Dam is a 13-meter (42 ft) high hydroelectric diversion dam on the Sandy River that is owned Run Hydroelectric project and began the process of creating a decommissioning plan for the dam

  12. Contaminant Stratigraphy of the Ballville Reservoir, Sandusky River, NW Ohio: Implications for Dam Removal

    E-Print Network [OSTI]

    Gottgens, Hans

    . Removal of the dam would require dredging or release downstream of 0.35 million m3 of sedi- ment to re for keeping the dam. Reasons to remove a dam might include economic obsolescence, safety issues, costs

  13. Review of Studies of Fish Survival in Spill at The Dalles Dam

    E-Print Network [OSTI]

    Review of Studies of Fish Survival in Spill at The Dalles Dam Independent Scientific Advisory BoardThe Dalles Dam Contents Assignment ................................................................................................................................................. 17 Appendix 4. Estimated Total Project Survival at The Dalles Dam at the Two Spill Levels

  14. The Downstream Geomorphic Effects of Dams: A Comprehensive and Comparative Approach

    E-Print Network [OSTI]

    Minear, Justin Toby

    2010-01-01T23:59:59.000Z

    gages used and the dates of the pre- and post-dam periods.and its alteration by dams. San Francisco Estuary andof water and sediment on rigid dam, J. Eng. Mech. , 119(7),

  15. Historical Population Structure of Central Valley Steelhead and Its Alteration by Dams

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    M. 2005. Creating a comprehensive dam dataset for assessingand its Alteration by Dams STEVEN T. LINDLEY 1 , ROBERT S.Pres- ently, impassable dams block access to 80% of

  16. The distribution of dams in Costa Rica and their hydrologic impacts

    E-Print Network [OSTI]

    Laurencio, Laura Richards

    2006-04-12T23:59:59.000Z

    Dam construction has increased exponentially over the past century, primarily in temperate environments. While the impacts of dams in temperate regions have been well-documented, a parallel level of research on dam impacts has not been achieved...

  17. The Downstream Geomorphic Effects of Dams: A Comprehensive and Comparative Approach

    E-Print Network [OSTI]

    Minear, Justin Toby

    2010-01-01T23:59:59.000Z

    Framework for Interpreting Downstream Effects of Dams onF. and N. Shin, 2001. The downstream effects of dams on theG.P. and M.G. Wolman, 1984. Downstream Effects of Dams on

  18. Using ArcGIS to extrapolate greenhouse gas emissions on the Pengxi River, a tributary of the Three Gorges Reservoir in China

    E-Print Network [OSTI]

    Yasarer, Lindsey

    2014-11-19T23:59:59.000Z

    Using ArcGIS to extrapolate greenhouse gas emissions on the Pengxi River, a tributary of the Three Gorges Reservoir in China Lindsey MW Yasarer, PhD Candidate, University of Kansas Dr. Zhe Li, Associate Professor, Chongqing University Dr...D Student, Chongqing University • Zhengyu Zhang and Xiao Yao, Masters Students, Chongqing University • CSTEC: China Science and Technology Exchange Center • NSF EAPSI Program The research was funded by the National Natural Science Foundation of China...

  19. Non-premixed acoustically perturbed swirling flame dynamics

    SciTech Connect (OSTI)

    Idahosa, Uyi; Saha, Abhishek; Xu, Chengying; Basu, Saptarshi [Department of Mechanical, Materials and Aerospace Engineering, University of Central Florida, Orlando, FL (United States)

    2010-09-15T23:59:59.000Z

    An investigation into the response of non-premixed swirling flames to acoustic perturbations at various frequencies (f{sub p}=0-315 Hz) and swirl intensities (S=0.09 and 0.34) is carried out. Perturbations are generated using a loudspeaker at the base of an atmospheric co-flow burner with resulting velocity oscillation amplitudes vertical stroke u'/U{sub avg} vertical stroke in the 0.03-0.30 range. The dependence of flame dynamics on the relative richness of the flame is investigated by studying various constant fuel flow rate flame configurations. Flame heat release rate is quantitatively measured using a photomultiplier with a 430 nm bandpass filter for observing CH* chemiluminescence which is simultaneously imaged with a phase-locked CCD camera. The flame response is observed to exhibit a low-pass filter characteristic with minimal flame response beyond pulsing frequencies of 200 Hz. Flames at lower fuel flow rates are observed to remain attached to the central fuel pipe at all acoustic pulsing frequencies. PIV imaging of the associated isothermal fields show the amplification in flame aspect ratio is caused by the narrowing of the inner recirculation zone (IRZ). Good correlation is observed between the estimated flame surface area and the heat release rate signature at higher swirl intensity flame configurations. A flame response index analogous to the Rayleigh criterion in non-forced flames is used to assess the potential for a strong flame response at specific perturbation configurations and is found to be a good predictor of highly responsive modes. Phase conditioned analysis of the flame dynamics yield additional criteria in highly responsive modes to include the effective amplitude of velocity oscillations induced by the acoustic pulsing. In addition, highly responsive modes were characterized by velocity to heat release rate phase differences in the {+-}{pi}/2 range. A final observed characteristic in highly responsive flames is a Strouhal number between 1 and 3.5 based on the burner co-flow annulus diameter (St = f{sub p}U{sub avg}/d{sub m}). Finally, wavelet analyses of heat release rate perturbations indicate highly responsive modes are characterized by sustained low frequency oscillations which accompany the high amplitude velocity perturbations at these modes. Higher intensity low frequency heat release rate oscillations are observed for lean flame/low pulsing frequency conditions. (author)

  20. Correlation of flame speed with stretch in turbulent premixed methane/air flames

    SciTech Connect (OSTI)

    Chen, J.H.; Im, H.G.

    1998-03-01T23:59:59.000Z

    Direct numerical simulations of two-dimensional unsteady premixed methane/air flames are performed to determine the correlation of flame speed with stretch over a wide range of curvatures and strain rates generated by intense two-dimensional turbulence. Lean and stoichiometric premixtures are considered with a detailed C{sub 1}-mechanism for methane oxidation. The computed correlation shows the existence of two distinct stable branches. It further shows that exceedingly large negative values of stretch can be obtained solely through curvature effects which give rise to an overall nonlinear correlation of the flame speed with stretch. Over a narrower stretch range, {minus}1 {le} Ka {le} 1, which includes 90% of the sample, the correlation is approximately linear, and hence, the asymptotic theory for stretch is practically applicable. Overall, one-third of the sample has negative stretch. In this linear range, the Markstein number associated with the positive branch is determined and is consistent with values obtained from comparable steady counterflow computations. In addition to this conventional positive branch, a negative branch is identified. This negative branch occurs when a flame cusp, with a center of curvature in the burnt gases, is subjected to intense compressive strain, resulting in a negative displacement speed. Negative flame speeds are also encountered for extensive tangential strain rates exceeding a Karlovitz number of unity, a value consistent with steady counterflow computations.

  1. Turbulent Nonpremixed Flames (TNF): Experimental Data Archives and Computational Submodels

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    In the 1990s an international collaboration formed around a series of workshops that became known collectively as the International Workshop on Measurement and Computation of Turbulent Non-Premixed Flames (TNF). An online library, hosted by Sandia National Laboratory (California) was established that provides data sets and submodels or "mechanisms" for the study of turbulence-chemistry interactions in turbulent nonpremixed and partially premixed combustion. Data are organized by flame types: simple jet flames, piloted jet flames, bluff body flames, and swirl flames. These data sets provide a means for collaborative comparisons of both measured and simulated/modeled research results and also assist scientists in determining priorities for further research. More than 20 data sets or databases are available from this website, along with various downloadable files of chemical mechanisms. The website also provides an extensive bibliography and the proceedings of the workshops themselves from 1996 through 2012. Information continues to be added to this collection.

  2. The advanced flame quality indicator system

    SciTech Connect (OSTI)

    Oman, R.; Rossi, M.J.; Calia, V.S.; Davis, F.L.; Rudin, A. [Insight Technologies, Inc., Bohemia, NY (United States)

    1997-09-01T23:59:59.000Z

    By combining oil tank monitoring, systems diagnostics and flame quality monitoring in an affordable system that communicates directly with dealers by telephone modem, Insight Technologies offers new revenue opportunities and the capability for a new order of customer relations to oil dealers. With co-sponsorship from New York State Energy Research and Development Authority, we have incorporated several valuable functions to a new product based on the original Flame Quality Indicator concept licensed from the US DOE`s Brookhaven National Laboratory. The new system is the Advanced Flame Quality Indicator, or AFQI. As before, the AFQI monitors and reports the intensity of the burner flame relative to a calibration established when the burner is set up at AFQI installation. Repairs or adjustments are summoned by late-night outgoing telephone calls when limits are exceeded in either direction, indicating an impending contamination or other malfunction. A independently, a pressure transducer for monitoring oil tank level and filter condition, safety lockout alarms and a temperature monitor; all reporting automatically at instructed intervals via an on-board modem to a central station PC computer (CSC). Firmware on each AFQI unit and Insight-supplied software on the CSC automatically interact to maintain a customer database for an oil dealer, an OEM, or a regional service contractor. In addition to ensuring continuously clean and efficient operation, the AFQI offers the oil industry a new set of immediate payoffs, among which are reduced outages and emergency service calls, shorter service calls from cleaner operation, larger oil delivery drops, the opportunity to stretch service intervals to as along as three years in some cases, new selling features to keep and attract customers, and greatly enhanced customer contact, quality and reliability.

  3. Soot Deposit Properties in Practical Flames

    SciTech Connect (OSTI)

    Preciado, Ignacio [University of Utah; Eddings, Eric G. [University of Utah; Sarofim, Adel F. [University of Utah; Dinwiddie, Ralph Barton [ORNL; Porter, Wallace D [ORNL; Lance, Michael J [ORNL

    2009-01-01T23:59:59.000Z

    Soot deposition from hydrocarbon flames was investigated in order to evaluate the evolution of the deposits during the transient process of heating an object that starts with a cold metal surface that is exposed to a flame. The study focused on the fire/metal surface interface and the critical issues associated with the specification of the thermal boundaries at this interface, which include the deposition of soot on the metal surface, the chemical and physical properties of the soot deposits and their subsequent effect on heat transfer to the metal surface. A laboratory-scale device (metallic plates attached to a water-cooled sampling probe) was designed for studying soot deposition in a laminar ethylene-air premixed flame. The metallic plates facilitate the evaluation of the deposition rates and deposit characteristics such as deposit thickness, bulk density, PAH content, deposit morphology, and thermal properties, under both water-cooled and uncooled conditions. Additionally, a non-intrusive Laser Flash Technique (in which the morphology of the deposit is not modified) was used to estimate experimental thermal conductivity values for soot deposits as a function of deposition temperature (water-cooled and uncooled experiments), location within the flame and chemical characteristics of the deposits. Important differences between water-cooled and uncooled surfaces were observed. Thermophoresis dominated the soot deposition process and enhanced higher deposition rates for the water-cooled experiments. Cooler surface temperatures resulted in the inclusion of increased amounts of condensable hydrocarbons in the soot deposit. The greater presence of condensable material promoted decreased deposit thicknesses, larger deposit densities, different deposit morphologies, and higher thermal conductivities.

  4. Clothes That Care -- Flame Resistant Protection.

    E-Print Network [OSTI]

    Kerbel, Claudia

    1980-01-01T23:59:59.000Z

    fabrics , how to care for FR clothing, how consumers can express opinions about flame-resistant gar ments and how consumers can avoid fires at home. Protection For . .. Certain groups are more likely to be involved in clothing fire accidents than... fr quently than in their proportional share of the population . People whose reflexes are slowed by drugs , alcohol , physical disability or mental illness are also susceptible to injury or death by fire be cause they cannot respond quickly...

  5. Simulation of spherically expanding turbulent premixed flames

    E-Print Network [OSTI]

    Ahmed, I.; Swaminathan, N.

    2013-09-16T23:59:59.000Z

    canonically im- portant configuration and its investigation is helpful to understand combustion in prac- tical devices such as the spark ignited internal combustion engine, modern stratified charge engines and accidental explosions of fuel vapour cloud... Simulation of spherically expanding turbulent premixed flames I. Ahmed, N. Swaminathan? Department of Engineering, Cambridge University, Cambridge, CB2 1PZ, UK. ?Corresponding author: Department of Engineering, Cambridge University, Trumpington...

  6. Distribution of bed sediment on Clear Creek after removal of Saeltzer Dam

    E-Print Network [OSTI]

    Clayton-Niederman, Z; Gilbreath, Alicia

    2005-01-01T23:59:59.000Z

    of Saeltzer Dam on Clear Creek: An Update, Water Resources83-138. Brown, Matt. 2004. Clear Creek anadromous salmonidto Dam Removal, Clear Creek, California, Water Resources

  7. Instituto Babcock Pamela Ruegg, Dam Rasmussen, y Doug Reinemann, Universidad de Wisconsin Instituto Babcock

    E-Print Network [OSTI]

    Sheridan, Jennifer

    Instituto Babcock © Pamela Ruegg, Dam Rasmussen, y Doug Reinemann, Universidad de Wisconsin. Pamela Ruegg, Dam Rasmussen, and Doug Reinemann Traductor: Matías Fernandez Introducción La producción y

  8. Analyzing and Tracking Burning Structures in Lean Premixed Hydrogen Flames

    E-Print Network [OSTI]

    Bremer, Peer-Timo

    2010-01-01T23:59:59.000Z

    structures in lean premixed hydrogen ?ames. Combustion andStructures in Lean Premixed Hydrogen Flames P. -T. Bremersimulations of lean hydrogen ?ames subject to different

  9. Soot precursor measurements in benzene and hexane diffusion flames

    SciTech Connect (OSTI)

    Kobayashi, Y.; Furuhata, T.; Amagai, K.; Arai, M. [Department of Mechanical System Engineering, Graduate School of Engineering, Gunma University, 1-5-1 Tenjin-cho, Kiryu-shi, Gunma 376-8515 (Japan)

    2008-08-15T23:59:59.000Z

    To clarify the mechanism of soot formation in diffusion flames of liquid fuels, measurements of soot and its precursors were carried out. Sooting diffusion flames formed by a small pool combustion equipment system were used for this purpose. Benzene and hexane were used as typical aromatic and paraffin fuels. A laser-induced fluorescence (LIF) method was used to obtain spatial distributions of polycyclic aromatic hydrocarbons (PAHs), which are considered as soot particles. Spatial distributions of soot in test flames were measured by a laser-induced incandescence (LII) method. Soot diameter was estimated from the temporal change of LII intensity. A region of transition from PAHs to soot was defined from the results of LIF and LII. Flame temperatures, PAH species, and soot diameters in this transition region were investigated for both benzene and hexane flames. The results show that though the flame structures of benzene and hexane were different, the temperature in the PAHs-soot transition region of the benzene flame was similar to that of the hexane flame. Furthermore, the relationship between the PAH concentrations measured by gas chromatography in both flames and the PAH distributions obtained from LIF are discussed. It was found that PAHs with smaller molecular mass, such as benzene and toluene, remained in both the PAHs-soot transition and sooting regions, and it is thought that molecules heavier than pyrene are the leading candidates for soot precursor formation. (author)

  10. adiabatic flame temperature: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    initial temperature 0 296 Knyazev, Vadim D. 6 Temperature field reconstruction of combustion flame based on high Engineering Websites Summary: radiant existence field on camera...

  11. Financial Analysis of Experimental Releases Conducted at Glen Canyon Dam

    E-Print Network [OSTI]

    Kemner, Ken

    Department of Energy Western Area Power Administration #12;ii FOREWORD This report was prepared by Argonne Canyon Dam (GCD) conducted for the U.S. Department of Energy's Western Area Power Administration (Western. The facilities known collectively as the Salt Lake City Area Integrated Projects include dams equipped for power

  12. FIELD TEST OF THE FLAME QUALITY INDICATOR

    SciTech Connect (OSTI)

    Andrew M. Rudin; Thomas Butcher; Henry Troost

    2003-02-04T23:59:59.000Z

    The flame quality indicator concept was developed at BNL specifically to monitor the brightness of the flame in a small oil burner and to provide a ''call for service'' notification when the brightness has changed from its setpoint, either high or low. In prior development work BNL has explored the response of this system to operational upsets such as excess air changes, fouled atomizer nozzles, poor fuel quality, etc. Insight Technologies, Inc. and Honeywell, Inc. have licensed this technology from the U.S. Department of Energy and have been cooperating to develop product offerings which meet industry needs with an optimal combination of function and price. Honeywell has recently completed the development of the Flame Quality Monitor (FQM or Honeywell QS7100F). This is a small module which connects via a serial cable to the burners primary operating control. Primary advantages of this approach are simplicity, cost, and ease of installation. Call-for-service conditions are output in the form of front panel indicator lights and contact closure which can trigger a range of external communication options. Under this project a field test was conducted of the FQM in cooperation with service organizations in Virginia, Pennsylvania, New Jersey, New York, and Connecticut. At total of 83 field sites were included. At each site the FQM was installed in parallel with another embodiment of this concept--the Insight AFQI. The AFQI incorporates a modem and provides the ability to provide detailed information on the trends in the flame quality over the course of the two year test period. The test site population was comprised of 79.5% boilers, 13.7% warm air furnaces, and 6.8% water heaters. Nearly all were of residential size--with firing rates ranging from 0.6 gallons of oil per hour to 1.25. During the course of the test program the monitoring equipment successfully identified problems including: plugged fuel lines, fouled nozzles, collapsed combustion chambers, and poor fuel pump cut-off. Service organizations can use these early indications to reduce problems and service costs. There were also some ''call-for-service'' indications for which problems were not identified. The test program also showed that monitoring of the flame can provide information on burner run times and this can be used to estimate current oversize factors and to determine actual fuel usage, enabling more efficient fuel delivery procedures.

  13. Non-Sooting, Low Flame Temperature Mixing-Controlled DI Diesel...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Sooting, Low Flame Temperature Mixing-Controlled DI Diesel Combustion Non-Sooting, Low Flame Temperature Mixing-Controlled DI Diesel Combustion 2003 DEER Conference Presentation:...

  14. US Society on Dams Annual Conference, March 2007, Philadelphia, Pennsylvania TOLERABLE RISK FOR DAMS: HOW SAFE IS SAFE ENOUGH?

    E-Print Network [OSTI]

    Bowles, David S.

    2 through a comprehensive and integrated consideration of the overall safety of a reservoir and value judgements. ICOLD (2005) ABSTRACT Risk assessment provides an opportunity to manage dam safety and Environmental Engineering and Director, Institute for Dam Safety Risk Management, Utah State University, Logan

  15. Phase 1: Dam, Lake, and Wetland The project's first phase was a dam and stormwater impoundment to control

    E-Print Network [OSTI]

    . Phase 3: Constructed Treatment Wetland (not publicly accessible) Six stormwater wetland cells surround Phase 1: Dam, Lake, and Wetland The project's first phase was a dam and stormwater impoundment to control surface water and groundwater hydrology. The surrounding wetlands were restored

  16. Lean and ultralean stretched propane-air counterflow flames

    SciTech Connect (OSTI)

    Cheng, Zhongxian; Pitz, Robert W. [Mechanical Engineering Department, Vanderbilt University, Box 1592, Station B, Nashville, TN 37235 (United States); Wehrmeyer, Joseph A. [Aerospace Testing Alliance, Building 1099, Avenue C, Arnold Air Force Base, TN 37389 (United States)

    2006-06-15T23:59:59.000Z

    Stretched laminar flame structures for a wide range of C{sub 3}H{sub 8}-air mixtures vs hot products are investigated by laser-based diagnostics and numerical simulation. The hot products are produced by a lean H{sub 2}-air premixed flame. The effect of stretch rate and equivalence ratio on four groups of C{sub 3}H{sub 8}-air flame structures is studied in detail by Raman scattering measurements and by numerical calculations of the major species concentration and temperature profiles. The equivalence ratio, f, is varied from a near-stoichiometric condition (f=0.86) to the sublean limit (f=0.44) and the stretch rate varies from 90 s{sup -1} to near extinction. For most of these C{sub 3}H{sub 8}-air lean mixtures, hot products are needed to maintain the flame. The significant feature of these flames is the relatively low flame temperatures (1200-1800 K). For this temperature range, the predicted C{sub 3}H{sub 8}-air flame structure is sensitive to the specific chemical kinetic mechanism. Two types of flame structures (a lean self-propagating flame and a lean diffusion-controlled flame) are obtained based on the combined effect of stretch and equivalence ratio. Three different mechanisms, the M5 mechanism, the Optimized mechanism, and the San Diego mechanism, are chosen for the numerical simulations. None of the propane chemical mechanisms give good agreement with the data over the entire range of flame conditions. (author)

  17. Adaptive low Mach number simulations of nuclear flame microphysics

    E-Print Network [OSTI]

    Bell, John B.

    Adaptive low Mach number simulations of nuclear flame microphysics J. B. Bell, M. S. Day, C. A of nuclear flames in Type Ia su- pernovae. This model is based on a low Mach number formulation nuclear burning. The formulation presented here generalizes low Mach number models used in combustion

  18. Vortex phase-jitter in acoustically excited bluff body flames

    E-Print Network [OSTI]

    Lieuwen, Timothy C.

    Vortex phase-jitter in acoustically excited bluff body flames Santosh J. Shanbhogue, Michael disturbances. Phase locked particle image velocimetry was carried out over a range of conditions", manifested as cycle-to-cycle variation in flame and vorticity field at the same excitation phase. Phase

  19. Iron/soot interaction in a laminar ethylene nonpremixed flame

    SciTech Connect (OSTI)

    Zhang, J.; Megaridis, C.M. [Univ. of Illinois, Chicago, IL (United States). Dept. of Mechanical Engineering

    1994-12-31T23:59:59.000Z

    A laminar, coannular, ethylene/air nonpremixed flame doped with ferrocene additive is employed to address the fundamental question of how iron becomes incorporated into the carbonaceous soot phase, thus interfering with the soot formation processes. The structure and chemical composition of individual aggregates are characterized with respect to flame coordinates via a combination of thermophoretic sampling, transmission electron microscopy, and energy dispersive spectrometry. Soot aggregate microstructure clearly reveals iron occlusion, as well as stratification of soot layers over the occluded phase. The study provides physical evidence that the soot and iron compounds combine in the flame to form a hybrid (inhomogeneous) particulate phase. The reported observations are consistent with the hypothesis that ferrocene decomposes early in the combustion process and before the onset of soot particle inception, thus forming a fine aerosol for the subsequent deposition of carbonaceous substances. Examination of a series of inhomogeneous soot aggregates shows that the flame aerosol composition varies with flame coordinates. In particular, aggregates transported in the soot annulus near the luminous flame front are primarily composed of carbon and oxygen, with traces of iron finely dispersed through the aggregate matrix. On the other hand, carbonaceous soot transported at low heights and near the flame axis contains iron in its elemental form. Finally, soot aggregates in all other areas of the flame contain both iron and oxygen, thus implying the possible presence of iron oxides within the carbonaceous matrix.

  20. Environmentally-benign Flame Retardant Nanocoating for Foam and Fabric 

    E-Print Network [OSTI]

    Cain, Amanda Ashley

    2014-12-09T23:59:59.000Z

    for the purpose of inhibiting or suppressing the combustion cycle. Inspiration for first applying polymer/clay thin films (i.e., nanobrick walls) as flame retardant (FR) coatings to polyurethane foam via LbL came from the final stage of a proposed flame...

  1. Bifurcations of flame filaments in chaotically mixed combustion reactions

    E-Print Network [OSTI]

    Gottwald, Georg A.

    Bifurcations of flame filaments in chaotically mixed combustion reactions Shakti N. Menon and Georg ranging fields. Be- sides in the case of combustion, where mixing-induced bifurcations may lead mixing has a significant effect on combustion processes and in particular on flame filamental structures

  2. SIEMENS-UV OPTICAL FLAME DETECTION MONA HEMENDRA RAITHATHA

    E-Print Network [OSTI]

    Sekhon, Jasjeet S.

    SIEMENS-UV OPTICAL FLAME DETECTION MONA HEMENDRA RAITHATHA College of Engineering University of tests conducted, as well as a cost and market analysis, the recommendation for Siemens would be to use.funginstitute.berkeley.edu #12;SIEMENS-UV OPTICAL FLAME DETECTION BY MONA HEMENDRA RAITHATHA THESIS Submitted in partial

  3. Measurements of Laminar Flame Velocity for Components of Natural Gas

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    flame velocity of components of natural gas, methane, ethane, propane, and nbutane as well as of binary% by volume (1). The laminar flame velocities of methane/air, ethane/air, and propane/air mixtures have on a plenum chamber with the radial temperature distribution measurement made by a series of thermocouples

  4. Modeling of NOx formation in circular laminar jet flames

    E-Print Network [OSTI]

    Siwatch, Vivek

    2007-04-25T23:59:59.000Z

    -premixed isolated circular laminar jet flame. The jet consists of the fuel rich inner region and the O2 rich outer region. The model estimates both thermal NOx and prompt NOx assuming single step kinetics for NOx formation and a thin flame model. Further the amount...

  5. Nanotechnology finding its way into flame retardancy

    SciTech Connect (OSTI)

    Schartel, Bernhard, E-mail: bernhard.schartel@bam.de [BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany)

    2014-05-15T23:59:59.000Z

    Nanotechnology is one of the key technologies of the 21{sup st} century. The exploitation of 'new' effects that arise from materials structured on the nano-scale has also been proposed successfully for flame retardancy of polymers since the end of the 90s. Of all of the approaches these include, at this time the use of nanocomposites offers the best potential for industrial application, also some other ideas are sketched, such as using electrospun nanofibers mats or layer-by-layer deposits as protection coatings, as well as sub-micrometer multilayer coatings as effective IR-mirrors. The general phenomena, inducing a flow limit in the pyrolysing melt and changing the fire residue, are identified in nanocomposites. Key experiments are performed such as quasi online investigation of the protection layer formation to understand what is going on in detail. The flame retardancy mechanisms are discussed and their impact on fire behaviour quantified. With the latter, the presentation pushes forward the state of the art. For instance, the heat shielding is experimentally quantified for a layered silicate epoxy resin nanocomposite proving that it is the only import mechanism controlling the reduction in peak heat release rate in the investigated system for different irradiations. The flame retardancy performance is assessed comprehensively illuminating not only the strengths but also the weak points of the concepts. Guidelines for materials development are deduced and discussed. Apart from inorganic fillers (layered silicate, boehmite, etc.) not only carbon nanoobjects such as multiwall carbon nanotubes, multilayer graphene and graphene are investigated, but also nanoparticles that are more reactive and harbor the potential for more beneficial interactions with the polymer matrix.

  6. Transition from cool flame to thermal flame in compression ignition process

    SciTech Connect (OSTI)

    Yamada, Hiroyuki; Suzaki, Kotaro; Goto, Yuichi [National Traffic Safety and Environment Laboratory, 7-42-27 Jindaiji-Higashimachi, Chofu, Tokyo 182-0012 (Japan); Tezaki, Atsumu [Department of Mechanical and Intellectual Systems Engineering, University of Toyama, Gofuku 3190, Toyama-shi, Toyama 930-8555 (Japan)

    2008-07-15T23:59:59.000Z

    The mechanism that initiates thermal flames in compression ignition has been studied. Experimentally, a homogeneous charge compression ignition (HCCI) engine was used with DME, n-heptane, and n-decane. Arrhenius plots of the heat release rate in the HCCI experiments showed that rates of heat release with DME, n-heptane, and n-decane exhibited a certain activation energy that is identical to that of the H{sub 2}O{sub 2} decomposition reaction. The same feature was observed in diesel engine operation using ordinary diesel fuel with advanced ignition timing to make ignition occur after the end of fuel injection. These experimental results were reproduced in nondimensional simulations using kinetic mechanisms for DME, n-heptane, and n-decane, the last being developed by extending the n-heptane mechanism. Methanol addition, which suppresses low-temperature oxidation (LTO) and delays the ignition timing, had no effect on the activation energy obtained from the Arrhenius plot of heat release rate. Nevertheless, methanol addition lowered the heat release rates during the prethermal flame process. This is because H{sub 2}O{sub 2} formation during cool flame was reduced by adding methanol. The mechanism during the transition process from cool flame to thermal flame can be explained quantitatively using thermal explosion theory, in which the rate-determining reaction is H{sub 2}O{sub 2} decomposition, assuming that heat release in this period is caused by partial oxidation of DME and HCHO initiated with the reaction with OH produced though H{sub 2}O{sub 2} decomposition. (author)

  7. Lean Flame Stabilization Ring - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville PowerCherries 82981-1cnHigh SchoolIn12electron 9 5 -of EnergyLeadership Leadership|Lean Flame

  8. Electrical probe diagnostics for the laminar flame quenching distance

    SciTech Connect (OSTI)

    Karrer, Maxime; Makarov, Maxime [Renault Technocentre, 78288 Guyancourt Cedex (France); Bellenoue, Marc; Labuda, Sergei; Sotton, Julien [Laboratoire de Combustion et de Detonique, CNRS, 86961 Futuroscope Chasseneuil (France)

    2010-02-15T23:59:59.000Z

    A simplified theory, previously developed for the general case of weakly ionized gas flow, is used to predict electrical probe response when the flame is quenched on the probe surface. This theory is based on the planar model of space charge sheaths around the measuring electrode. For the flame quenching case, by assuming that the sheath thickness is comparable with the thermal boundary layer thickness, probe current can be related to flame quenching distance. The theoretical assumptions made to obtain the analytical formulation of probe current were experimentally proved by using direct visualization and high-frequency PIV. The direct visualization method was also used to validate the results of flame quenching distance values obtained with electrical probe. The electrical probe diagnostics have been verified for both head-on and sidewall flame quenching regimes and for stoichiometric methane/air and propane/air mixtures in a pressure range of 0.05-0.6 MPa. (author)

  9. Trapping and aerogelation of nanoparticles in negative gravity hydrocarbon flames

    SciTech Connect (OSTI)

    Chakrabarty, Rajan K., E-mail: rajan.chakrabarty@gmail.com [Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130 (United States); Laboratory for Aerosol Science, Spectroscopy, and Optics, Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512 (United States); Novosselov, Igor V. [Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195 (United States); Enertechnix Inc., Maple Valley, Washington 98068 (United States); Beres, Nicholas D.; Moosmüller, Hans [Laboratory for Aerosol Science, Spectroscopy, and Optics, Desert Research Institute, Nevada System of Higher Education, Reno, Nevada 89512 (United States); Sorensen, Christopher M. [Condensed Matter Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506 (United States); Stipe, Christopher B. [TSI Incorporated, 500 Cardigan Rd, Shoreview, Minnesota 55126 (United States)

    2014-06-16T23:59:59.000Z

    We report the experimental realization of continuous carbon aerogel production using a flame aerosol reactor by operating it in negative gravity (?g; up-side-down configuration). Buoyancy opposes the fuel and air flow forces in ?g, which eliminates convectional outflow of nanoparticles from the flame and traps them in a distinctive non-tipping, flicker-free, cylindrical flame body, where they grow to millimeter-size aerogel particles and gravitationally fall out. Computational fluid dynamics simulations show that a closed-loop recirculation zone is set up in ?g flames, which reduces the time to gel for nanoparticles by ?10{sup 6}?s, compared to positive gravity (upward rising) flames. Our results open up new possibilities of one-step gas-phase synthesis of a wide variety of aerogels on an industrial scale.

  10. Quantifying and Generalizing Hydrologic Responses to Dam Regulation using a Statistical Modeling Approach

    SciTech Connect (OSTI)

    McManamay, Ryan A [ORNL

    2014-01-01T23:59:59.000Z

    Despite the ubiquitous existence of dams within riverscapes, much of our knowledge about dams and their environmental effects remains context-specific. Hydrology, more than any other environmental variable, has been studied in great detail with regard to dam regulation. While much progress has been made in generalizing the hydrologic effects of regulation by large dams, many aspects of hydrology show site-specific fidelity to dam operations, small dams (including diversions), and regional hydrologic regimes. A statistical modeling framework is presented to quantify and generalize hydrologic responses to varying degrees of dam regulation. Specifically, the objectives were to 1) compare the effects of local versus cumulative dam regulation, 2) determine the importance of different regional hydrologic regimes in influencing hydrologic responses to dams, and 3) evaluate how different regulation contexts lead to error in predicting hydrologic responses to dams. Overall, model performance was poor in quantifying the magnitude of hydrologic responses, but performance was sufficient in classifying hydrologic responses as negative or positive. Responses of some hydrologic indices to dam regulation were highly dependent upon hydrologic class membership and the purpose of the dam. The opposing coefficients between local and cumulative-dam predictors suggested that hydrologic responses to cumulative dam regulation are complex, and predicting the hydrology downstream of individual dams, as opposed to multiple dams, may be more easy accomplished using statistical approaches. Results also suggested that particular contexts, including multipurpose dams, high cumulative regulation by multiple dams, diversions, close proximity to dams, and certain hydrologic classes are all sources of increased error when predicting hydrologic responses to dams. Statistical models, such as the ones presented herein, show promise in their ability to model the effects of dam regulation effects at large spatial scales as to generalize the directionality of hydrologic responses.

  11. TSSGNEO suggestions for refinement of safety criteria for dam at the Sayano-Shushenskaya HPP

    SciTech Connect (OSTI)

    Savich, A. I.; Gaziev, E. G. [Expert Commission on Assessment of the 'Dam - Bed' System at the Sayano-Shushenskaya HPP (Russian Federation)] [Expert Commission on Assessment of the 'Dam - Bed' System at the Sayano-Shushenskaya HPP (Russian Federation)

    2013-09-15T23:59:59.000Z

    Analysis of radial-displacements of the dam, measured by direct and inverted plumb lines, indicates that curves of the variation in radial displacements of the dam at different elevations make it possible to plot diagrams of increases in the radial displacement over the entire height of the dam, i.e., inclines of the axis of the dam to the vertical.

  12. On the Modeling and Simulation of Non-Hydrostatic Dam Break Flows

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    by the failure of the dam structure. The determination of the potential consequences of a dam break requiresOn the Modeling and Simulation of Non-Hydrostatic Dam Break Flows Alexandre Caboussat S´ebastien Boyaval Alexandre Masserey January 1, 2013 Abstract The numerical simulation of three-dimensional dam

  13. Institute for Water Resources, US Army Corps of Engineers Australian National Committee on Large Dams

    E-Print Network [OSTI]

    Bowles, David S.

    Committee on Large Dams LIFESim: A Model for Estimating Dam Failure Life Loss DRAFT by Maged A. Aboelata ABSTRACT Catastrophic events such as dam failures or severe floods are considered to be of low probability linked circumstances surrounding historical dam failure events to actual loss of life and produced

  14. Signature of Rhine Valley sturzstrom dam failures in Holocene sediments of Lake Constance, Germany

    E-Print Network [OSTI]

    Gilli, Adrian

    Signature of Rhine Valley sturzstrom dam failures in Holocene sediments of Lake Constance, Germany that the hyperpycnite deposits are directly related to the failure of two sturzstrom dams and the draining of the dammed and Schuster, 1988). Landslide-dammed lake failures constitute a major hazard to downstream areas (Eis- bacher

  15. Morphological responses and sediment processes following a typhoon-induced dam failure, Dahan

    E-Print Network [OSTI]

    Tullos, Desiree

    Morphological responses and sediment processes following a typhoon-induced dam failure, Dahan River gravel and sand was exposed when Barlin Dam failed during Typhoon WeiPa in 2007. The dam was located configuration, and distance from the dam is needed to explain the rate and pattern of morphological changes

  16. Experimental Study on Impact Load on a Dam Due to Debris Flow1

    E-Print Network [OSTI]

    Standiford, Richard B.

    as a fluid hits the dam (fluid impact load). The former tends to cause partial break of the concrete damExperimental Study on Impact Load on a Dam Due to Debris Flow1 lwao Miyoshi2 ABSTRACT When a dam is struck by mud or debris flow, it is put under a great impact load and sometimes is destroyed. To prevent

  17. The horizontal dam break problem for slow non-Newtonian power-law fluids

    E-Print Network [OSTI]

    The horizontal dam break problem for slow non-Newtonian power-law fluids P. Saramito a C. Smutek bLaboratoire g´eosciences ­ IPGP et universit´e de La R´eunion, France Abstract ­ The dam break problem shallow for the horizontal dam break problem. Keywords ­ viscoplastic fluid; dam break problem; shallow flows. 1

  18. Introduction to the special issue: Understanding and linking the biophysical, socioeconomic and geopolitical effects of dams

    E-Print Network [OSTI]

    Tullos, Desiree

    , socioeconomic and geopolitical effects of dams 1. Introduction Dams have made important contributions to human develop- ment, and the benefits derived from them have been considerable (World Commission on Dams, 2000). With the rising global popu- lation and desire to increase quality of life, dams are prominently staged to deliver

  19. Does Small Dam Removal Affect Local Property Values? An Empirical Analysis Bill Provencher

    E-Print Network [OSTI]

    Provencher, R. William

    Does Small Dam Removal Affect Local Property Values? An Empirical Analysis Bill Provencher of small dam removal on property values in south-central Wisconsin. Data on residential property sales were obtained for three categories of sites: those where a dam is intact, those where a dam was recently removed

  20. Thermal Monitoring of Embankment Dams by Fiber Optics Y. L. Beck1

    E-Print Network [OSTI]

    Boyer, Edmond

    Thermal Monitoring of Embankment Dams by Fiber Optics Y. L. Beck1 , A. A. Khan1 , P. Cunat1 , C an embankment dam changes its temperature field. In this regard, fiber optics buried in the structures can of embankment dams. Introduction Erosion of hydraulic embankments like dams and dikes, specially the internal

  1. Sediment from hydraulic mining detained by Englebright and small dams in the Yuba basin

    E-Print Network [OSTI]

    James, L. Allan

    Sediment from hydraulic mining detained by Englebright and small dams in the Yuba basin L. Allan substantial modifications or removal of Englebright Dam, a large dam (86 million m3 capacity) built by the U organizations, therefore, is examining aspects of various dam-treatment scenarios that range from no action

  2. Explores Dam Removal Located in Southwest Ohio, Buck Creek and its

    E-Print Network [OSTI]

    Bogaerts, Steven

    OHIO Researcher Explores Dam Removal Located in Southwest Ohio, Buck Creek and its tributary, Beaver Creek, run through a series of low-head dams in Springfield, Ohio. Historically, the four dams of the four dams. This will help restore the natural flow of sediments and fish along the entire river

  3. Downstream hydrologic and geomorphic effects of large dams on American rivers

    E-Print Network [OSTI]

    Downstream hydrologic and geomorphic effects of large dams on American rivers William L. Graf including more than 75,000 dams. One hundred thirty-seven of the very large dams, each storing 1.2 km3 (106 effects of these very large dams emerge from an analysis of the stream gage records of 72 river reaches

  4. DOWNSTREAM CHANNEL CHANGES AFTER A SMALL DAM REMOVAL: USING AERIAL PHOTOS AND MEASUREMENT ERROR FOR CONTEXT;

    E-Print Network [OSTI]

    Tullos, Desiree

    DOWNSTREAM CHANNEL CHANGES AFTER A SMALL DAM REMOVAL: USING AERIAL PHOTOS AND MEASUREMENT ERROR to assess downstream channel changes associated with a small dam removal. The Brownsville Dam, a 2.1 m tall downstream from the dam and in an upstream control reach using aerial photos (1994­2008) and in the field

  5. Dynamics of premixed flames in a narrow channel with a step-wise wall temperature

    E-Print Network [OSTI]

    Daraio, Chiara

    . [1], in their experiments on methane/air and propane/air premixed flames in cylindrical tubes of 2 mm al. [10], asymmetric flames were found in fuel-lean methane/air mixtures burning in a rectangular flame structure was experi- mentally observed for lean propane/air flames in tubes at condi- tions close

  6. Route-Specific Passage Proportions and Survival Rates for Fish Passing through John Day Dam, The Dalles Dam, and Bonneville Dam in 2010 and 2011

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Carlson, Thomas J.

    2012-06-04T23:59:59.000Z

    This report fulfills a request of the U.S. Army Engineer District, Portland, Oregon, to produce an interim report of estimates of route-specific fish passage proportions and survival rates for lower Columbia River dams in 2010 and 2011. The estimates are needed to update the Compass Model for the Columbia River Treaty and the new Biological Opinion before detail technical reports are published in late 2012. This report tabulates route-specific fish-passage proportions and survival rates for steelhead and Chinook salmon smolts passing through various sampled routes at John Day Dam, The Dalles Dam, and Bonneville Dam in 2010 and 2011. Results were compiled from analyses of data acquired in spring 2010 and 2011 studies that were specifically designed to estimate dam-passage and forebay-to-tailrace survival rates, travel time metrics, and spill passage efficiency, as stipulated by the 2008 Federal Columbia River Power System Biological Opinion and the Columbia Basin Fish Accords. The study designs allowed for estimation of route-specific fish passage proportions and survival rates as well as estimation of forebay-passage survival, all of which are summarized herein.

  7. Regulation of Dams and Bridges Affecting Navigable Waters (Wisconsin)

    Broader source: Energy.gov [DOE]

    Chapter 31 of the Wisconsin Statutes lays out the regulations relevant to dams and bridges on or near navigable waters. This statute establishes that the Department of Natural Resources has...

  8. Rules and Regulations for Dam Safety (Rhode Island)

    Broader source: Energy.gov [DOE]

    These rules and regulations seek to provide for the safety of dams to protect the public, real property, and natural resources by establishing reasonable standards and creating a public record for...

  9. aswan high dam: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laval, Qubec, Qubec, Canada G1V 0A6 a b s t r a c ta r t i c l e i n f climate change marine sedimentation river damming spectral analysis Gulf of St. Lawrence...

  10. Travertine Deposits of Soda Dam, New Mexico, and Their Implications...

    Open Energy Info (EERE)

    Travertine Deposits of Soda Dam, New Mexico, and Their Implications for the Age and Evolution of the Valles Caldera Hydrothermal System Jump to: navigation, search OpenEI Reference...

  11. Early warning systems: An economic approach to dam safety

    SciTech Connect (OSTI)

    Taylor, B.D. [National Weather Service Colorado River Basin Forecasting Center, Salt Lake City, UT (United States)

    1995-10-01T23:59:59.000Z

    An early warning system can provide a relatively low-cost method for addressing dam safety issues. Bureau of Reclamation engineers have developed a systematic approach for designing warning systems while effectively balancing safety and economic concerns. Rather than addressing the dam itself, the system addresses the embayment and those meteorological/hydrological factors affecting the embayment. Characteristics of the mathematical model developed are addressed in this paper.

  12. Providing protection: Agencies receive funding to repair, upgrade dams

    E-Print Network [OSTI]

    Wythe, Kathy

    2009-01-01T23:59:59.000Z

    Story by Kathy Wythe tx H2O | pg. 26 Providing protection Agencies receive funding to repair, upgrade dams along with local partners, can apply for grant funds, he said. Construction of the dams began through four federal authorizations..., called floodwater retarding structures and built mostly in rural areas during the 1950s to 1970s, are aging and need repairing. Others now protect urban areas that have developed downstream and need upgrading to meet more stringent safety standards...

  13. GRAVITATIONALLY UNSTABLE FLAMES: RAYLEIGH-TAYLOR STRETCHING VERSUS TURBULENT WRINKLING

    SciTech Connect (OSTI)

    Hicks, E. P. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and the Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Rosner, R., E-mail: eph2001@columbia.edu [Computation Institute, University of Chicago, 5735 S. Ellis Ave., Chicago, IL 60637 (United States)

    2013-07-10T23:59:59.000Z

    In this paper, we provide support for the Rayleigh-Taylor-(RT)-based subgrid model used in full-star simulations of deflagrations in Type Ia supernovae explosions. We use the results of a parameter study of two-dimensional direct numerical simulations of an RT unstable model flame to distinguish between the two main types of subgrid models (RT or turbulence dominated) in the flamelet regime. First, we give scalings for the turbulent flame speed, the Reynolds number, the viscous scale, and the size of the burning region as the non-dimensional gravity (G) is varied. The flame speed is well predicted by an RT-based flame speed model. Next, the above scalings are used to calculate the Karlovitz number (Ka) and to discuss appropriate combustion regimes. No transition to thin reaction zones is seen at Ka = 1, although such a transition is expected by turbulence-dominated subgrid models. Finally, we confirm a basic physical premise of the RT subgrid model, namely, that the flame is fractal, and thus self-similar. By modeling the turbulent flame speed, we demonstrate that it is affected more by large-scale RT stretching than by small-scale turbulent wrinkling. In this way, the RT instability controls the flame directly from the large scales. Overall, these results support the RT subgrid model.

  14. Measurements and large eddy simulation of propagating premixed flames

    SciTech Connect (OSTI)

    Masri, A.R.; Cadwallader, B.J. [School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, Sydney, NSW 2006 (Australia); Ibrahim, S.S. [Department of Aeronautical and Automotive Engineering, Loughborough University, Loughborough LE11 3TU (United Kingdom)

    2006-07-15T23:59:59.000Z

    This paper presents an experimental and numerical study of unsteady turbulent premixed flames igniting in an initially stagnant mixture and propagating past solid obstacles. The objective here is to study the outstanding issue of flow-flame interactions in transient premixed combustion environments. Particular emphasis is placed on the burning rate and the structure of the flame front. The experimental configuration consists of a chamber with a square cross-section filled with a combustible mixture of propane-air ignited from rest. An array of baffle plates as well as geometrical obstructions of varying shapes and blockage ratios, are placed in the path of the flame as it propagates from the ignition source to the vented end of the enclosure. A range of flame propagation conditions are studied experimentally. Measurements are presented for pressure-time traces, high-speed images of the flame front, mean velocities obtained from particle imaging velocimetry and laser induced fluorescence images of the hydroxyl radical OH. Three-dimensional large eddy simulations (LES) are also made for a case where a square obstacle and an array of baffle plates are placed in the chamber. The dynamic Germano model and a simple flamelet combustion model are used at the sub-grid scale. The effects of grid size and sub-grid filter width are also discussed. Calculations and measurements are found to be in good agreement with respect to flame structure and peak overpressure. Turbulence levels increase significantly at the leading edge of the flame as it propagates past the array of baffle plates and the obstacle. With reference to the regime diagrams for turbulent premixed combustion, it is noted that the flame continues to lie in the zones of thin reactions or corrugated flamelets regardless of the stage of propagation along the chamber. (author)

  15. Saeltzer Dam Removal on Clear Creek 11 years later: An assessment of upstream channel changes since the dam's removal

    E-Print Network [OSTI]

    Simons, Crystal; Walker, Katelyn; Zimring, Mark

    2011-01-01T23:59:59.000Z

    pages. Brown, M. (n.d. ). Clear Creek—McCormick-Saeltzer DamBrown, M. (2011). 2011 Clear Creek Technical Team Report froAssessment: Lower Clear Creek Anadromous Fish Restoration &

  16. Numerical Investigation of Scaling Properties of Turbulent Premixed Flames

    E-Print Network [OSTI]

    J. C. Niemeyer; A. R. Kerstein

    1997-07-09T23:59:59.000Z

    Gibson scaling and related properties of flame-surface geometry in turbulent premixed combustion are demonstrated using a novel computational model, Deterministic Turbulent Mixing (DTM). In DTM, turbulent advection is represented by a sequence of maps applied to the computational domain. The structure of the mapping sequence incorporates pertinent scaling properties of the turbulent cascade. Here, combustion in Kolmogorov turbulence (kinetic-energy cascade) and in Bolgiano-Obukhov convective turbulence (potential-energy cascade) is simulated. Implications with regard to chemical flames and astrophysical (thermonuclear) flames are noted.

  17. Envir202b Earth, Air, Water: the Human Context Winter 2003 F. Stahr The River Dammed: Proposed Removal of the Lower Snake River Dams A Case Study

    E-Print Network [OSTI]

    Envir202b ­ Earth, Air, Water: the Human Context Winter 2003 F. Stahr The River Dammed: Proposed Removal of the Lower Snake River Dams ­ A Case Study Assignment & Schedule for Day 2 We will next work as your group will be asked to answer the following questions: 1) What changes (if any) to the dams

  18. Longitudinal and seasonal variation of stream N uptake in an urbanizing watershed: effect of organic matter, stream size, transient storage and debris dams

    E-Print Network [OSTI]

    Claessens, Luc; Tague, Christina L.; Groffman, Peter M.; Melack, John M.

    2010-01-01T23:59:59.000Z

    streams, organic debris dams can play an important role inin ?ow velocity when debris dams are hydraulically activecontact time. Therefore, debris dams can have an important

  19. Temporary Restoration of Bull Trout Passage at Albeni Falls Dam

    SciTech Connect (OSTI)

    Paluch, Mark; Scholz, Allan; McLellan, Holly [Eastern Washington University Department of Biology; Olson, Jason [Kalispel Tribe of Indians Natural Resources Department

    2009-07-13T23:59:59.000Z

    This study was designed to monitor movements of bull trout that were provided passage above Albeni Falls Dam, Pend Oreille River. Electrofishing and angling were used to collect bull trout below the dam. Tissue samples were collected from each bull trout and sent to the U. S. Fish and Wildlife Service Abernathy Fish Technology Center Conservation Genetics Lab, Washington. The DNA extracted from tissue samples were compared to a catalog of bull trout population DNA from the Priest River drainage, Lake Pend Oreille tributaries, and the Clark Fork drainage to determine the most probable tributary of origin. A combined acoustic radio or radio tag was implanted in each fish prior to being transported and released above the dam. Bull trout relocated above the dam were able to volitionally migrate into their natal tributary, drop back downstream, or migrate upstream to the next dam. A combination of stationary radio receiving stations and tracking via aircraft, boat, and vehicle were used to monitor the movement of tagged fish to determine if the spawning tributary it selected matched the tributary assigned from the genetic analysis. Seven bull trout were captured during electrofishing surveys in 2008. Of these seven, four were tagged and relocated above the dam. Two were tagged and left below the dam as part of a study monitoring movements below the dam. One was immature and too small at the time of capture to implant a tracking tag. All four fish released above the dam passed by stationary receivers stations leading into Lake Pend Oreille and no fish dropped back below the dam. One of the radio tags was recovered in the tributary corresponding with the results of the genetic test. Another fish was located in the vicinity of its assigned tributary, which was impassable due to low water discharge at its mouth. Two fish have not been located since entering the lake. Of these fish, one was immature and not expected to enter its natal tributary in the fall of 2008. The other fish was large enough to be mature, but at the time of capture its sex was unable to be determined, indicating it may not have been mature at the time of capture. These fish are expected to enter their natal tributaries in early summer or fall of 2009.

  20. Experimental Endeavour on a Pillar of Flame: Space Shuttle Rises...

    Energy Savers [EERE]

    flash and a flame . . . a rush and a roar . . . a bright white bird booming into a deep blue sky: Few science experiments ever begin in such spectacular fashion. Yet the Space...

  1. Temperature field reconstruction of combustion flame based on high

    E-Print Network [OSTI]

    that sound propagates in a different medium with different speed, and its theo- retical cornerstone-known materials of solid, liquid, and gaseous states, flame is a kind of plasma1,2 of which temper- ature is one

  2. TRACES Centre Thermo iCE 3500 Flame AA Spectrometer

    E-Print Network [OSTI]

    Wells, Mathew G. - Department of Physical and Environmental Sciences, University of Toronto

    TRACES Centre Thermo iCE 3500 Flame AA Spectrometer Standard Operating Procedure 1. Turn on the lamp icon a. ID the lamp of choice and click the `Off' button to `On' b. Non-Thermo lamps MUST

  3. Surface wettability studies of PDMS using flame plasma treatment

    E-Print Network [OSTI]

    Wang, Xin C

    2009-01-01T23:59:59.000Z

    The flame plasma treatment studied in this thesis was able to oxidize the surface of Polydimethylsiloxane (PDMS) in a fraction of a second. It was found to be a much faster way to modify PDMS surface wettability than the ...

  4. Physics-based flame dynamics modeling and thermoacoustic instability mitigation

    E-Print Network [OSTI]

    Altay, Hurrem Murat

    2009-01-01T23:59:59.000Z

    The objectives of this work are (i) to investigate the coupled unsteady heat release mechanisms responsible for thermoacoustic instabilities under different flame anchoring configurations, (ii) to develop reduced-order ...

  5. The effect of fuel composition on flame dynamics

    SciTech Connect (OSTI)

    Hendricks, Adam G.; Vandsburger, Uri [Department of Mechanical Engineering - 0238, Virginia Tech, Blacksburg, VA 24061 (United States)

    2007-10-15T23:59:59.000Z

    As fuel sources diversify, the gas turbine industry is under increasing pressure to develop fuel-flexible plants, able to use fuels with a variety of compositions from a large range of sources. However, the dynamic characteristics vary considerably with composition, in many cases altering the thermoacoustic stability of the combustor. We compare the flame dynamics, or the response in heat release rate of the flame to acoustic perturbations, of the three major constituents of natural gas: methane, ethane, and propane. The heat release rate is quantified using OH* chemiluminescence and product gas temperature. Gas temperature is measured by tracking the absorption of two high-temperature water lines, via Tunable Diode Laser Absorption Spectroscopy. The flame dynamics of the three fuels differ significantly. The changes in flame dynamics due to variations in fuel composition have the potential to have a large effect on the thermoacoustic stability of the combustor. (author)

  6. Probing flame chemistry with MBMS, theory, and modeling

    SciTech Connect (OSTI)

    Westmoreland, P.R. [Univ. of Massachusetts, Amherst (United States)

    1993-12-01T23:59:59.000Z

    The objective is to establish kinetics of combustion and molecular-weight growth in C{sub 3} hydrocarbon flames as part of an ongoing study of flame chemistry. Specific reactions being studied are (1) the growth reactions of C{sub 3}H{sub 5} and C{sub 3}H{sub 3} with themselves and with unsaturated hydrocarbons and (2) the oxidation reactions of O and OH with C{sub 3}`s. This approach combines molecular-beam mass spectrometry (MBMS) experiments on low-pressure flat flames; theoretical predictions of rate constants by thermochemical kinetics, Bimolecular Quantum-RRK, RRKM, and master-equation theory; and whole-flame modeling using full mechanisms of elementary reactions.

  7. Influence of gas compression on flame acceleration in the early stage of burning in tubes

    E-Print Network [OSTI]

    Valiev, Damir; Kuznetsov, Mikhail; Eriksson, Lars-Erik; Law, Chung K; Bychkov, Vitaly

    2012-01-01T23:59:59.000Z

    The mechanism of finger flame acceleration at the early stage of burning in tubes has been observed experimentally by Clanet and Searby [Combust. Flame 105: 225 (1996)] for slow propane-air flames, and elucidated analytically and computationally by Bychkov et al. [Combust. Flame 150: 263 (2007)] in the limit of an incompressible flow. We analytically, experimentally and computationally study herein the finger flame acceleration for fast burning flames, when the gas compressibility assumes an important role. Specifically, we have developed a theory through small Mach number expansion up to the first-order terms, demonstrating that gas compression reduces the acceleration rate and thereby moderates the finger flame acceleration noticeably. We have also conducted experiments for hydrogen-oxygen mixtures with considerable initial values of the Mach number, showing finger flame acceleration with the acceleration rate much smaller than those obtained previously for hydrocarbon flames. Furthermore, we have performed...

  8. Numerical and experimental investigation of vortical flow-flame interaction

    SciTech Connect (OSTI)

    Najm, H.N.; Schefer, R.W.; Milne, R.B.; Mueller, C.J. [Sandia National Labs., Livermore, CA (United States); Devine, K.D.; Kempka, S.N. [Sandia National Labs., Albuquerque, NM (United States)

    1998-02-01T23:59:59.000Z

    A massively parallel coupled Eulerian-Lagrangian low Mach number reacting flow code is developed and used to study the structure and dynamics of a forced planar buoyant jet flame in two dimensions. The numerical construction uses a finite difference scheme with adaptive mesh refinement for solving the scalar conservation equations, and the vortex method for the momentum equations, with the necessary coupling terms. The numerical model construction is presented, along with computational issues regarding the parallel implementation. An experimental acoustically forced planar jet burner apparatus is also developed and used to study the velocity and scalar fields in this flow, and to provide useful data for validation of the computed jet. Burner design and laser diagnostic details are discussed, along with the measured laboratory jet flame dynamics. The computed reacting jet flow is also presented, with focus on both large-scale outer buoyant structures and the lifted flame stabilization dynamics. A triple flame structure is observed at the flame base in the computed flow, as is theoretically expected, but was not observable with present diagnostic techniques in the laboratory flame. Computed and experimental results are compared, along with implications for model improvements.

  9. On the Evolution of Thermonuclear Flames on Large Scales

    E-Print Network [OSTI]

    Ju Zhang; O. E. Bronson Messer; Alexei M. Khokhlov; Tomasz Plewa

    2006-10-05T23:59:59.000Z

    The thermonuclear explosion of a massive white dwarf in a Type Ia supernova explosion is characterized by vastly disparate spatial and temporal scales. The extreme dynamic range inherent to the problem prevents the use of direct numerical simulation and forces modelers to resort to subgrid models to describe physical processes taking place on unresolved scales. We consider the evolution of a model thermonuclear flame in a constant gravitational field on a periodic domain. The gravitational acceleration is aligned with the overall direction of the flame propagation, making the flame surface subject to the Rayleigh-Taylor instability. The flame evolution is followed through an extended initial transient phase well into the steady-state regime. The properties of the evolution of flame surface are examined. We confirm the form of the governing equation of the evolution suggested by Khokhlov (1995). The mechanism of vorticity production and the interaction between vortices and the flame surface are discussed. The results of our investigation provide the bases for revising and extending previous subgrid-scale model.

  10. Experimental and Computational Study of Flame Inhibition Mechanisms of Halogenated Compounds in C1-C3 Alkanes Flames

    E-Print Network [OSTI]

    Osorio Amado, Carmen H

    2013-07-30T23:59:59.000Z

    suppressants on ignition and laminar flame propagation of C_(1)-C_(3) alkanes premixed mixtures, as good representatives of flammable gas fires (Class B fires). This methodology integrates model formulations and experimental designs in order to examine both...

  11. Fact Sheet - The Snake River Dam Study-Then and Now - November...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in 2002, evaluated four alternatives to help Snake River fall chinook get through the dams. The independent peer-reviewed study concluded that dam breaching by itself would not...

  12. Merowe Dam and the inundation of paleochannels of the Nile

    E-Print Network [OSTI]

    Sparavigna, Amelia Carolina

    2010-01-01T23:59:59.000Z

    The course of the Nile in northern Sudan follows a contorted path through bedrocks, creating the Great Bend. Few years ago, the satellite images showed a fertile strip of land with villages, where paleochannels of the river hosted many fields with cultivations and archaeological sites. Now, a huge part of this valley is under the waters of Merowe Dam reservoir. Comparing the images of the region before and after the dam gates were closed, we can see that the reservoir created itself through flooding the paleochannels.

  13. Investigation of H2 Concentration and Combustion Instability Effects on the Kinetics of Strained Syngas Flames

    SciTech Connect (OSTI)

    Ahsan R. Choudhuri

    2006-08-07T23:59:59.000Z

    The flame extinction limits of syngas (H{sub 2}-CO) flames were measured using a twin-flame-counter-flow burner. Plots of Extinction limits vs. global stretch rates were generated at different mixture compositions and an extrapolation method was used to calculate the flame extinction limit corresponding to an experimentally unattainable zero-stretch condition. The zero-stretch extinction limit of H{sub 2}-CO mixtures decreases (from rich to lean) with the increase in H{sub 2} concentration in the mixture. The average difference between the measured flame extinction limit and the Le Chatelier's calculation is around {approx} 7%. The measured OH{sup -} chemiluminescent data indicates that regardless of mixture compositions the OH radical concentration reduces (within the experimental uncertainties) to an extinction value prior to the flame extinction. Flame extinction limits of H{sub 2}-CO mixtures measured in a flat-flame burner configuration also show a similar relation. Additionally, the measured laminar flame velocity close to the extinction indicates that regardless of fuel composition the premixed flame of hydrogen fuel blends extinguishes when the mixture laminar flame velocity falls below a critical value. The critical laminar flame velocity at extinction for H{sub 2}-CO premixed flames (measured in the flat flame burner configuration) is found to be 3.77({+-}0.38) cm/s. An externally perturbed H{sub 2}-CO twin flame was not experimentally achievable for the mixture conditions used in the present investigation. A slightest perturbation in the flow-field distorts the H{sub 2}-CO twin-flame. The flame becomes highly unstable with the introduction of an externally excited flow oscillation.

  14. The structure of the carbon black flame

    E-Print Network [OSTI]

    Anderson, W. Kermi

    1945-01-01T23:59:59.000Z

    BLACK FLAME A Dissertation By William Kermit Anderson THEHSR UCOF 120925 TNLKMDiserstsKa aony WHR1mo WdpvmlcyfEyS lnR1 R1WvpS 1nS nvfyARyfh vySS Rm R1y SyuyoWc nvfnunfHWcS Wvf fybWoRgyvRS l1m dmmbyoWRyf Rm gWpy R1nS lmop bmSSnAcy. xbydnWc R1Wvp...S Woy fHy Rm R1y PmccmlnvE gygAyoS mP R1y. SRWPP mP R1y TEondHcRHoWc Wvf tyd1WvndWc NmccyEy mP ayqWS. am eo. joyf D. :yvSyv Pmo Ryd1vndWc 1ycb Wvf Pmo vHgyomHS SHEEySRnmvS mP uWcHy. am eo. N. N. 9yfEyS Pmo PnvWvdnWc Wnf Wvf yqdych cyvR dmmbyo...

  15. Compliance Monitoring of Subyearling Chinook Salmon Smolt Survival and Passage at Bonneville Dam, Summer 2012

    SciTech Connect (OSTI)

    Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.

    2013-05-01T23:59:59.000Z

    The purpose of this compliance study was to estimate dam passage survival of subyearling Chinook salmon at Bonneville Dam during summer 2012, as required by the 2008 Federal Columbia River Power System Biological Opinion. The study also estimated smolt passage survival from the forebay 2 km upstream of the dam to the tailrace 1 km below the dam, as well as forebay residence time, tailrace egress, and spill passage efficiency, as required in the 2008 Columbia Basin Fish Accords.

  16. Wildlife Impact Assessment and Summary of Previous Mitigation Related to Hydroelectric Projects in Montana, Phase 1, Volume Two (B), Clark Fork River Projects, Cabinet Gorge and Noxon Rapids Dams, Operator, Washington Water Power Company.

    SciTech Connect (OSTI)

    Wood, Marilyn

    1984-06-01T23:59:59.000Z

    This report documents best available information concerning the wildlife species impacted and the degree of the impact. A target species list was developed to focus the impact assessment and to direct mitigation efforts. Many non-target species also incurred impacts but are not discussed in this report. All wildlife habitats inundated by the two reservoirs are represented by the target species. It was assumed the numerous non-target species also affected will be benefited by the mitigation measures adopted for the target species. Impacts addressed are limited to those directly attributable to the loss of habitat and displacement of wildlife populations due to the construction and operation of the two hydroelectric projects. Secondary impacts, such as the relocation of railroads and highways, and the increase of the human population, were not considered. In some cases, both positive and negative impacts were assessed; and the overall net effect was reported. The loss/gain estimates reported represent impacts considered to have occurred during one point in time except where otherwise noted. When possible, quantitative estimates were developed based on historical information from the area or on data from similar areas. Qualitative loss estimates of low, moderate, or high with supporting rationale were assessed for each species or species group.

  17. Assessment of Downstream Hazard Potential for Dam Failure in Rhode Island Primary Investigators

    E-Print Network [OSTI]

    Rhode Island, University of

    Assessment of Downstream Hazard Potential for Dam Failure in Rhode Island Primary Investigators Assessment of Downstream Hazard Potential for Dam Failure in Rhode Island Mayrai Gindy, University of Rhode.3 Hazard Classification of the Federal Emergency Management Agency .............. 11 2.4 General Dam Design

  18. Evaluation of Seepage from an Embankment Dam Retaining Pedro J. Amaya1

    E-Print Network [OSTI]

    piping is one of the most common and catastrophic failure modes of an earthen dam (Sher ard et al. 1963Evaluation of Seepage from an Embankment Dam Retaining Fly Ash Pedro J. Amaya1 ; John T. Massey of fly ash-laden seepage from the right abutment of an earthen dam are presented herein

  19. Analysis of Dam Failure in the Saluda River February 8, 2005

    E-Print Network [OSTI]

    Morrow, James A.

    Analysis of Dam Failure in the Saluda River Valley February 8, 2005 Abstract We identify and model two possible failure modes for the Saluda Dam: gradual failure due to an enlarging breach and sudden catas- trophic failure due to liqui#12;cation of the dam. For the #12;rst case we de- scribe the breach

  20. Under consideration for publication in J. Fluid Mech. 1 Dam breaking seiches

    E-Print Network [OSTI]

    Balmforth, Neil

    hazards should the dam break suddenly. Indeed, geological evidence points to a number of recent failures & Evans 2000). One of the principal causes of moraine dam failure is claimed to be catastrophic erosional et al. 2002; Cao et al. 2004). By contrast, the failure of a moraine-dammed lake has never been

  1. Peak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA

    E-Print Network [OSTI]

    Received 6 May 2005 Availble online 7 February 2006 Abstract The failure of a lava dam 165,000 yr ago dam-failure and unsteady flow modeling to estimate a peak discharge and flow hydrograph. FailurePeak discharge of a Pleistocene lava-dam outburst flood in Grand Canyon, Arizona, USA Cassandra R

  2. Final Independent External Peer Review Report Mohawk Dam Major Rehabilitation Report

    E-Print Network [OSTI]

    US Army Corps of Engineers

    and to minimize the potential for catastrophic failure of the dam during such events. Several alternatives wereFinal Independent External Peer Review Report Mohawk Dam Major Rehabilitation Report Warsaw, Ohio Report Mohawk Dam Major Rehabilitation Report Warsaw, Ohio by Battelle 505 King Avenue Columbus, OH 43201

  3. Revised Final Independent External Peer Review Report for the East Branch Dam, Clarion River,

    E-Print Network [OSTI]

    US Army Corps of Engineers

    was assigned a Dam Safety Action Classification (DSAC) rating of II, generally indicating that failure couldRevised Final Independent External Peer Review Report for the East Branch Dam, Clarion River, Elk County, Pennsylvania: Dam Safety Modification Report Prepared by Battelle Memorial Institute Prepared

  4. Late Pleistocene earthquake-triggered moraine dam failure and outburst of Lake Zurich, Switzerland

    E-Print Network [OSTI]

    Gilli, Adrian

    Late Pleistocene earthquake-triggered moraine dam failure and outburst of Lake Zurich, Switzerland of $20,600 m3 sÀ1 . We also discuss long-term causes and short-term trigger mechanisms of the dam failure of Lake Zurich was initiated as a consequence of the moraine dam failure that either was triggered

  5. STUDY OF LOSS AND DELAY OF SALMON PASSING ROCK ISLAND DAM, COLUMBIA RIVER, 1954-56

    E-Print Network [OSTI]

    ). Six new generating unit.s were added in t.he powerhouse (locat.ed on the left. side of t.he dam returns from below and above dam releases were compared; data failed to show that the dam caused losses

  6. Research Article Effects of Alpine hydropower dams on particle transport and

    E-Print Network [OSTI]

    Gilli, Adrian

    Research Article Effects of Alpine hydropower dams on particle transport and lacustrine December 2006 Abstract. The effects of high-alpine hydropower damming on lacustrine sedimentation impact, such as by hydropower dam construction that form artifi- cial sediment sinks acting as manmade

  7. The influence of large dams on surrounding climate and precipitation patterns

    E-Print Network [OSTI]

    Niyogi, Dev

    The influence of large dams on surrounding climate and precipitation patterns Ahmed Mohamed Degu,1 February 2011. [1] Understanding the forcings exerted by large dams on local climate is key to establishing formation are identified around the reservoir shoreline for 92 large dams of North America. Our study

  8. AN ESTIMATE OF MORTALITY OF CHINOOK SALMON IN THE COLUMBIA RIVER NEAR BONNEVILLE DAM DURING THE

    E-Print Network [OSTI]

    AN ESTIMATE OF MORTALITY OF CHINOOK SALMON IN THE COLUMBIA RIVER NEAR BONNEVILLE DAM DURING Dam and studied t!:te probable causes of death. The estimates of numbers of dead fish were made from ratios of tagged to untagged floating carcasses below the dam. Tagged s!llmon carcasses were released

  9. SANBA Tool: Knowledge Capitalisation and Lessons Learned on Dams and their Safety

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    SANBA Tool: Knowledge Capitalisation and Lessons Learned on Dams and their Safety C. Curt 1 , H Aubière Cedex, France E-mail: corinne.curt@irstea.fr Summary Much is known about dam design, construction for dam design, construction and failure and degradation modes (domain knowledge), coupled with a case

  10. Historical Population Structure of Central Valley Steelhead and its Alteration by Dams

    E-Print Network [OSTI]

    May, Bernie

    Historical Population Structure of Central Valley Steelhead and its Alteration by Dams STEVEN T. Pres- ently, impassable dams block access to 80% of historically available habitat, and block access Steelhead, O. mykiss, endangered species, population structure, dispersal, habitat model, dams, Central

  11. Debris dams and the relief of headwater streams Stephen T. Lancaster a,, Gordon E. Grant b

    E-Print Network [OSTI]

    Debris dams and the relief of headwater streams Stephen T. Lancaster a,, Gordon E. Grant b, mountain landscapes where debris flows are common, their deposition commonly forms valley-spanning dams these dams causes alluviation in what would otherwise be bedrock channels. In this paper, the effects

  12. The Dalles Lock and Dam welcomes raptor (and human) visitors during Eagle Watch 2013

    E-Print Network [OSTI]

    US Army Corps of Engineers

    The Dalles Lock and Dam welcomes raptor (and human) visitors during Eagle Watch 2013 By Amber Tilton, The Dalles Lock and Dam park ranger Nestled between Oregon and Washington is the Columbia River District operates three dams on the Columbia River where visitors and employees alike often spot America

  13. RE-ASSEMBLING HETCH HETCHY: Water Supply Implications of Removing O'Shaughnessy Dam

    E-Print Network [OSTI]

    Lund, Jay R.

    1 RE-ASSEMBLING HETCH HETCHY: Water Supply Implications of Removing O'Shaughnessy Dam Sarah E. Null The Hetch Hetchy System provides San Francisco with much of its water supply. O'Shaughnessy Dam is one of its conveyance. Removing O'Shaughnessy Dam has gained interest for restoring Hetch Hetchy Valley

  14. Multichannel Analysis of Surface Wave An Application to Diagnose Dam Bodies

    E-Print Network [OSTI]

    Barrash, Warren

    Multichannel Analysis of Surface Wave ­ An Application to Diagnose Dam Bodies Noppadol Poomvises it use as a part of geological program to explore an appropriated rock foundation at a proposed dam location, but also use to investigate the condition of dam after water being storage as well

  15. Homogenization of regional river dynamics by dams and global biodiversity implications

    E-Print Network [OSTI]

    Poff, N. LeRoy

    Homogenization of regional river dynamics by dams and global biodiversity implications N. Le differ- ences in climate and geology. Extensive construction of dams by humans has greatly dampened to regional-scale environmental templates caused by dams is largely unexplored but of critical conservation

  16. Effect of spill on adult salmon passage delay at Columbia River and Snake River dams

    E-Print Network [OSTI]

    Washington at Seattle, University of

    Effect of spill on adult salmon passage delay at Columbia River and Snake River dams W. Nicholas dams in the Columbia/Snake River hydrosystem may delay the upstream passage of the adults. To evaluate-to-day variations of spill and upstream fish passage at the eight dams of the Columbia/Snake river hydrosystem

  17. Analyse retard des mesures d'auscultation de barrages Delayed response analysis of dam monitoring data

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of dam monitoring data Stéphane Bonelli Cemagref Unité de recherche Ouvrages hydrauliques et équipements. Long series of monitoring data are obtained during the routine operation of a dam. To understand the long term behaviour of a dam, it is essential to carefully interpret the dissipative effects which tend

  18. Spatial variability of sea level rise due to water impoundment behind dams

    E-Print Network [OSTI]

    Conrad, Clint

    dams Julia W. Fiedler1 and Clinton P. Conrad2 Received 29 March 2010; revised 12 May 2010; accepted 18 May 2010; published 19 June 2010. [1] Dams have impounded 10,800 km3 of water since 1900, reducing depresses the earth's surface near dams and elevates the geoid, which locally increases relative sea level

  19. New French Guidelines for Structural Safety of Embankment Dams in a Semi-probabilistic Format

    E-Print Network [OSTI]

    Boyer, Edmond

    New French Guidelines for Structural Safety of Embankment Dams in a Semi-probabilistic Format P in France and in most countries, hydraulic works (dams and levees) have remained excluded from semi rules. In this context, the French Committee on Large Dams ­ FRCOLD - initiated, with a panel of experts

  20. French Guidelines for Structural Safety of Gravity Dams in a Semi-probabilistic Format

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    French Guidelines for Structural Safety of Gravity Dams in a Semi-probabilistic Format Paul Royet1 the French Committee on Dams and Reservoirs ­ FrCOLD - issued provisional guidelines for structural safety of gravity dams. It was the first attempt to produce a semi-probabilistic limit-state method for the design

  1. The Dam1 kinetochore complex harnesses microtubule dynamics to produce force

    E-Print Network [OSTI]

    Asbury, Chip

    The Dam1 kinetochore complex harnesses microtubule dynamics to produce force and movement Charles L-dependent force production is unknown. Recent work suggests that the Dam1 complex, an essential component assay where beads coated with pure recombinant Dam1 complex were bound to the tips of individual dynamic

  2. Disentangling dam impacts in river networks1 Kris Van Looy, Thierry Tormos and Yves Souchon2

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Disentangling dam impacts in river networks1 Kris Van Looy, Thierry Tormos and Yves Souchon2 3 100 VILLEURBANNE Cedex7 +33 (0)4 72 20 89 418 Kris.van-looy@irstea.fr9 10 11 Abstract12 Damming is one the presence and density of dams and biological metrics of river16 health in the context of a variety

  3. Glen Canyon Dam, Fluctuating Water Levels, and Riparian Breeding Birds: The Need for Management Compromise

    E-Print Network [OSTI]

    I ;'. I Glen Canyon Dam, Fluctuating Water Levels, and Riparian Breeding Birds: The Need.--Large water releases from Glen Canyon Dam in May and June are harmful to riparian breeding birds along' INTRODUCTION 100,000,.... COLORAOQ RIVER NEAR GRAND CANYON (PHANTOM RANCHi The completion of Glen Canyon Dam

  4. Effect of Flow Pulses on Degradation Downstream of Hapcheon Dam, South Korea

    E-Print Network [OSTI]

    Julien, Pierre Y.

    Effect of Flow Pulses on Degradation Downstream of Hapcheon Dam, South Korea Young Ho Shin1 and Pierre Y. Julien, M.ASCE2 Abstract: The changes in channel geometry downstream of Hapcheon Dam, South sluice gate operations affect the 45-km reach of the Hwang River between the Hapcheon Reregulation Dam

  5. TOWARDS OBJECTIVE DESIGN OF DRY DAMS AT WATERSHED SCALE: HOW TO TAKE INTO ACCOUNT THE SPATIAL

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    21 TOWARDS OBJECTIVE DESIGN OF DRY DAMS AT WATERSHED SCALE: HOW TO TAKE INTO ACCOUNT THE SPATIAL, the best location for 1 or 3 dry dams). To take into account the spatial variability of the rainfall, we, following subcatchments delineation. A dry dam can be placed at the outlet of any unit. Such a simple model

  6. PREDICTING UNDERSEEPAGE OF MASONRY DAMS Published in Proceedings of 29th

    E-Print Network [OSTI]

    PREDICTING UNDERSEEPAGE OF MASONRY DAMS Published in Proceedings of 29th ASDSO Conference (1934) selected conservative values of safe creep ratios because of the small number of dam failures judgment is recommended in designing a dam for safety against piping, and Lane's values are a starting

  7. A dam agem odelwith non-convex freeenergy for quasi-brittlem aterials

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A dam agem odelwith non-convex freeenergy for quasi-brittlem aterials M arc Francois January 12 isintroduced in a dam age m echanics m odelrele- vantforthe quasi-brittle m aterials.Itisshown thatitdescribesthe large dilatancy ofconcrete undercom pression and the di erentlocalization an- gles and dam age

  8. Independent External Peer Review Report Rough River Dam 18 August 2011 ii

    E-Print Network [OSTI]

    US Army Corps of Engineers

    #12;Independent External Peer Review Report ­ Rough River Dam 18 August 2011 ii This page intentionally blank. #12;Independent External Peer Review Report ­ Rough River Dam 18 August 2011 iii Table Panel Members B-1 Appendix C ­ Charge for IEPR Panel C-1 List of Figures Figure 1. Rough River Dam 4

  9. STATISTICAL AND 3D NONLINEAR FINITE ELEMENT ANALYSIS OF SCHLEGEIS DAM

    E-Print Network [OSTI]

    Balaji, Rajagopalan

    STATISTICAL AND 3D NONLINEAR FINITE ELEMENT ANALYSIS OF SCHLEGEIS DAM VICTOR SAOUMA, ERIC HANSEN is composed of two parts. First a statistical analysis of the dam crest displacement is performed, along with a prediction for the years 2000-2001. Then a 3D finite element analysis of Schlegeis dam is performed using

  10. The dynamics of travertine dams . Hammer , D.K. Dysthe, B. Jamtveit

    E-Print Network [OSTI]

    Dysthe, Dag Kristian

    The dynamics of travertine dams Ø. Hammer , D.K. Dysthe, B. Jamtveit PGP-Physics of Geological 2007 Abstract We present a simple, abstract model for travertine dam formation. The simulation uses, implies a classical pattern formation system with a characteristic dam size, however this wavelength

  11. Landslide-dammed paleolake perturbs marine sedimentation and drives genetic change

    E-Print Network [OSTI]

    Roering, Joshua J.

    Landslide-dammed paleolake perturbs marine sedimentation and drives genetic change in anadromous by forming dams, forcing upstream ag- gradation of water and sediment, and generating catastrophic out- burst floods. Less apparent is the effect of large landslide dams on river ecosystems and marine sedimentation

  12. ACCURACY OF ESTIMATION OF BREEDING VALUES FOR BULL DAMS by H. O. GRAVERT K. PABST

    E-Print Network [OSTI]

    Boyer, Edmond

    ACCURACY OF ESTIMATION OF BREEDING VALUES FOR BULL DAMS by H. O. GRAVERT K. PABST Institute for Milk Production, Fedeval Daivy Research Center, Kiel, F.R.G. For 1.229 dams of A.I. bulls with known IN A BULL DAM SELECTION INDEX A. FESTERLING Institut f. Tierzucht Universitlits Bonn, Bonn, B.R.D. The bull

  13. Hugo van Dam and the dynamic adjoint function Imre Pa zsit*

    E-Print Network [OSTI]

    Pázsit, Imre

    Hugo van Dam and the dynamic adjoint function Imre Pa´ zsit* Department of Reactor Physics, Chalmers University of Technology, SE-412 96 Go¨teborg, Sweden Dedicated to Prof. Dr. Hugo van Dam into perspective the seminal contribution of Hugo van Dam to the development of neutron noise diagnostics

  14. Effects of magnetite on high-frequency ground-penetrating radar Remke L. Van Dam1

    E-Print Network [OSTI]

    Borchers, Brian

    Effects of magnetite on high-frequency ground-penetrating radar Remke L. Van Dam1 , Jan M. H, paleoclimatology (Maher and Thompson, 1995), soil development (Singer et al., 1996; Van Dam et al., 2008 et al., 2011), the detection of unexploded ordnance (UXO) and land mines (Van Dam et al., 2005

  15. Effects of upstream dams versus groundwater pumping on stream temperature under varying climate conditions

    E-Print Network [OSTI]

    Click Here for Full Article Effects of upstream dams versus groundwater pumping on stream impact of a large upstream dam versus inreach groundwater pumping on stream temperatures was analyzed large dams are present, such as the western United States or eastern Australia. Stream temperatures were

  16. THE DISTRIBUTIONAL IMPACT OF DAMS: EVIDENCE FROM CROPLAND PRODUCTIVITY IN AFRICA

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    THE DISTRIBUTIONAL IMPACT OF DAMS: EVIDENCE FROM CROPLAND PRODUCTIVITY IN AFRICA Eric STROBL Robert of Dams: Evidence from Cropland Productivity in Africa Eric Strobl*, ** Ecole Polytechnique & Robert the distributional impact of major dams on cropland productivity in Africa. As our unit of analysis we use

  17. Green River Lake and Dam interim plan benefits ecosystem By John Hickey

    E-Print Network [OSTI]

    US Army Corps of Engineers

    11 Green River Lake and Dam interim plan benefits ecosystem By John Hickey Hydrologic Engineering that water is released from Green River Dam in Kentucky. In May 2006, the interim plan was approved shown that operation of Green River Dam can be changed in ways that improve ecosystems while continuing

  18. LEARNING FROM DAM REMOVAL MONITORING: CHALLENGES TO SELECTING EXPERIMENTAL DESIGN AND ESTABLISHING SIGNIFICANCE OF OUTCOMES

    E-Print Network [OSTI]

    Tullos, Desiree

    LEARNING FROM DAM REMOVAL MONITORING: CHALLENGES TO SELECTING EXPERIMENTAL DESIGN AND ESTABLISHING, California, USA ABSTRACT As the decommissioning of dams becomes a common restoration technique, decisions about dam removals must be based on sound predictions of expected outcomes. Results of past and ongoing

  19. Measuring the erodibility of soil materials constituting earth embankments: a key input for dams and levees

    E-Print Network [OSTI]

    Boyer, Edmond

    Measuring the erodibility of soil materials constituting earth embankments: a key input for dams of hydraulic embankment structures, including earth embankment dams, levees and dykes, is a major concern all over the world. Still today, about one to two large dams fail every year and hundreds, probably

  20. Development of spatial pattern in large woody debris and debris dams in streams

    E-Print Network [OSTI]

    Kraft, Clifford E.

    Development of spatial pattern in large woody debris and debris dams in streams Clifford E. Kraft years after wood deposition, we surveyed individual pieces of LWD in one stream and surveyed debris dam locations in eight streams within the ice storm area. To examine the linear pattern of debris dams within

  1. Earthquake behavior of arch dams Chuhan Zhang, Yanjie Xu, Guanglun Wang & Feng Jin

    E-Print Network [OSTI]

    Spencer Jr., B.F.

    Earthquake behavior of arch dams Chuhan Zhang, Yanjie Xu, Guanglun Wang & Feng Jin Department millennium, construction of a series of high arch dams up to 250-300m in height is being planned or conducted (Table 1). Table 1. Project data and Design PVA Project Dam height (m) Reservoir capacity (109 m3 ) Power

  2. Dam breaking by wave-induced erosional incision N. J. Balmforth,1

    E-Print Network [OSTI]

    Balmforth, Neil

    Dam breaking by wave-induced erosional incision N. J. Balmforth,1 J. von Hardenberg,2 A. Provenzale displacement wave can lead to catastrophic erosional incision of a moraine damming a glacial lake that a single wave is generally unable to break the dam, but a sufficiently large disturbance in an almost

  3. Proceedings of the Australian Committee on Large Dams Conference, Melbourne, Victoria, Australia. November 2004

    E-Print Network [OSTI]

    Bowles, David S.

    Proceedings of the Australian Committee on Large Dams Conference, Melbourne, Victoria, Australia. November 2004 ANCOLD 2004 Conference Page 1 TRANSPORTATION MODEL FOR EVACUATION IN ESTIMATING DAM FAILURE and requiring only a reasonable level of effort to #12;Proceedings of the Australian Committee on Large Dams

  4. Nonlinear effects of stretch on the flame front propagation

    SciTech Connect (OSTI)

    Halter, F.; Tahtouh, T.; Mounaim-Rousselle, C. [Institut PRISME, Universite d'Orleans, 8 rue Leonard de Vinci, 45072 Orleans Cedex 2 (France)

    2010-10-15T23:59:59.000Z

    In all experimental configurations, the flames are affected by stretch (curvature and/or strain rate). To obtain the unstretched flame speed, independent of the experimental configuration, the measured flame speed needs to be corrected. Usually, a linear relationship linking the flame speed to stretch is used. However, this linear relation is the result of several assumptions, which may be incorrected. The present study aims at evaluating the error in the laminar burning speed evaluation induced by using the traditional linear methodology. Experiments were performed in a closed vessel at atmospheric pressure for two different mixtures: methane/air and iso-octane/air. The initial temperatures were respectively 300 K and 400 K for methane and iso-octane. Both methodologies (linear and nonlinear) are applied and results in terms of laminar speed and burned gas Markstein length are compared. Methane and iso-octane were chosen because they present opposite evolutions in their Markstein length when the equivalence ratio is increased. The error induced by the linear methodology is evaluated, taking the nonlinear methodology as the reference. It is observed that the use of the linear methodology starts to induce substantial errors after an equivalence ratio of 1.1 for methane/air mixtures and before an equivalence ratio of 1 for iso-octane/air mixtures. One solution to increase the accuracy of the linear methodology for these critical cases consists in reducing the number of points used in the linear methodology by increasing the initial flame radius used. (author)

  5. Measurements of the structure of turbulent premixed and stratified methane/air flames

    E-Print Network [OSTI]

    Sweeney, Mark

    2011-11-08T23:59:59.000Z

    was entirely due to deviation from stoichiometry and the corresponding reduction in local reaction rate. Poinsot et al [34] performed three-dimensional reduced chemistry simulations of turbulent strat- ified propane/air flames with a Gaussian distribution... that stratification increased the flame propagation rate. The local variation in burning velocity was accompanied by an increase in flame front wrinkling relative to premixed flames, with a corresponding broadening of curvature distributions. Pasquier et al [22...

  6. James W. Van Dam US Burning Plasma Organization

    E-Print Network [OSTI]

    focus: magnetically confined plasmas #12;Page 5 USBPO What is a "burning" plasma? · "Burning" plasmaJames W. Van Dam US Burning Plasma Organization US ITER Project Office Institute for Fusion Studies Plasmas -- A Tutorial -- Supported by Office of Science #12;Page 2 USBPO The next frontier · Understanding

  7. Optimization of Hydroacoustic Equipment Deployment at Foster Dam, 2013

    SciTech Connect (OSTI)

    Hughes, James S.; Johnson, Gary E.; Ploskey, Gene R.; Hennen, Matthew J.; Fischer, Eric S.; Zimmerman, Shon A.

    2013-03-01T23:59:59.000Z

    The goal of the study was to optimize performance of the fixed-location hydroacoustic systems at Foster Dam (FOS) by determining deployment and data acquisition methods that minimized structural, electrical, and acoustic interference. Optimization of the hydroacoustic systems will establish methodology for sampling by active acoustic methods during this year-long evaluation of juvenile salmonid passage at FOS.

  8. INCORPORATING UNCERTAINTY INTO DAM SAFETY RISK Sanjay S. Chauhan1

    E-Print Network [OSTI]

    Chauhan, Sanjay S.

    on the topic of uncertainty in quantitative risk and policy analysis the reader is referred to Morgan to incorporating input uncertainties into risk analysis model. Input uncertainties are captured by using for uncertainty analysis in dam safety risk assessment, and demonstrates some useful formats for presenting

  9. Solid bitumen at Atigun Gorge, central Brooks Range front: Implications for oil exploration in the North Slope fold and thrust belt

    SciTech Connect (OSTI)

    Howell, D.G.; Johnsson, M.J.; Bird, K.J. (U.S. Geological Survey, Menlo Park, CA (United States))

    1991-03-01T23:59:59.000Z

    The Atigun Gorge area of the north-central Brooks range is a structurally complex region in which a sequence of north-verging duplex structures involving Paleozoic and Mesozoic Ellesmerian continental margin deposits are structurally overlain by a south-verging thrust of Brookian foreland basin deposits of Albian age. The resulting structural triangle zone is marked by numerous small-scale thrusts involving Permian and Triassic strata in which solid bitumen, occupying fissures up to 10 cm wide and several meters in length, has been found. The presence of aromatics in the odorless, black material was confirmed by ultraviolet fluorescence following extraction in dichloromethane. The occurrence of solid bitumen at Atigun Gorge adds to a growing inventory of hydrocarbon-filled fractures found mostly in Cretaceous rocks in the Brooks Range foothills. These occurrences are consistent with a model of hydrocarbon generation beneath the northern margin of the Brooks Range. The regional distribution of vitrinite reflectance isograds suggests that the northern margin of the Brooks Range and the adjoining foreland basin deposits of the North Slope have experienced similar thermal histories. The 0.6% vitrinite reflectance isograd intersects the land surface along the southern margin of the foreland and the 2.0% isograd lies within the northern part of the range. Although these relations suggest the possibility of petroleum resources at shallow depths beneath the Brooks Range foothills, they also indicate that a considerable amount of differential uplift has occurred, probably resulting in redistribution and some leakage of any oil and gas accumulations.

  10. Fractal characterisation of high-pressure and hydrogen-enriched CH4air turbulent premixed flames

    E-Print Network [OSTI]

    Gülder, �mer L.

    Fractal characterisation of high-pressure and hydrogen-enriched CH4­air turbulent premixed flames measurements were performed to obtain the flame front images, which were further analyzed for fractal of the flame front curvature as a function of the pressure. Fractal dimension showed a strong dependence

  11. Prediction of oxy-coal flame stand-off using high-fidelity thermochemical models

    E-Print Network [OSTI]

    Prediction of oxy-coal flame stand-off using high-fidelity thermochemical models and the one Abstract An Eulerian one-dimensional turbulence (ODT) model is applied to simulate oxy-coal combustion temperature and mixing rate on oxy-coal flame is simulated and discussed where flame stand-off is used

  12. Kinetic effects of toluene blending on the extinction limit of n-decane diffusion flames

    E-Print Network [OSTI]

    Ju, Yiguang

    analyses of kinetic path ways and species transport on flame extinction were also conducted. The results and emission properties, such as the ignition delay times, extinction limits, flame speeds, species profilesKinetic effects of toluene blending on the extinction limit of n-decane diffusion flames Sang Hee

  13. Blowoff characteristics of bluff-body stabilized conical premixed flames under upstream velocity modulation

    SciTech Connect (OSTI)

    Chaparro, Andres A.; Cetegen, Baki M. [Mechanical Engineering Department, University of Connecticut, Storrs, CT 06269-3139 (United States)

    2006-01-01T23:59:59.000Z

    This article presents experimental findings on the blowoff characteristics of conical premixed flames anchored at their apex by three different flame holders (rod, disk, and cone) in the presence of upstream velocity oscillations. Experiments were performed with propane-air mixtures at mixture velocities approaching the flame holder of 5, 10, and 15 m/s. The flow speed was modulated sinusoidally at frequencies up to 400 Hz with a constant-velocity modulation amplitude of u{sub rms}/U{sub m}=0.08 upstream of the flame holder. It was found that the blowoff equivalence ratio exhibits a dependence on the flow modulation frequency. Specifically, at low approach velocities (5 m/s), the effect of upstream flow modulation is to improve flame stability as evidenced by lower flame blowoff equivalence ratios for all three types of flame holders considered. At higher approach velocities (10 and 15 m/s), the disk- and cone-shaped flame holders exhibit less stability with increasing excitation frequency. The rod-shaped flame holder behavior is different at these higher velocities in that the flow modulation still provides enhanced flame stability. The flame stability results are supplemented with a detailed analysis of the flow field in the flame stabilization zone obtained by particle image velocimetry.

  14. Premixed turbulent flame front structure investigation by Rayleigh scattering in the thin

    E-Print Network [OSTI]

    Gülder, Ömer L.

    in propane flames. The probability density function of curvature showed a Gaussian-like distribution at all­air and propane­air stabilized on a bunsen type burner were studied using planar Rayleigh scattering and particle flames, and from 0.7 to stoichiometric for propane flames. The non-dimensional turbulence rms velocity, u

  15. Turbulent Oxygen Flames in Type Ia Supernovae A. J. Aspden1

    E-Print Network [OSTI]

    Turbulent Oxygen Flames in Type Ia Supernovae A. J. Aspden1 , J. B. Bell1 , and S. E. Woosley2 oxygen flames. The two aims of the paper are to examine the response of the inductive oxygen flame to intense levels of turbulence, and to explore the possibility of transition to detonation in the oxygen

  16. LES/probability density function approach for the simulation of an ethanol spray flame

    E-Print Network [OSTI]

    Raman, Venkat

    LES/probability density function approach for the simulation of an ethanol spray flame Colin Heye a an experimental pilot-stabilized ethanol spray flame. In this particular flame, droplet evaporation occurs away: Large-eddy simulation; Probability density function; Flamelet/progress variable approach; Ethanol

  17. A review of proposed Glen Canyon Dam interim operating criteria

    SciTech Connect (OSTI)

    LaGory, K.; Hlohowskyj, I.; Tomasko, D.; Hayse, J.; Durham, L.

    1992-04-01T23:59:59.000Z

    Three sets of interim operating criteria for Glen Canyon Dam on the Colorado River have been proposed for the period of November 1991, to the completion of the record of decision for the Glen Canyon Dam environmental impact statement (about 1993). These criteria set specific limits on dam releases, including maximum and minimum flows, up-ramp and down-ramp rates, and maximum daily fluctuation. Under the proposed interim criteria, all of these parameters would be reduced relative to historical operating criteria to protect downstream natural resources, including sediment deposits, threatened and endangered fishes, trout, the aquatic food base, and riparian plant communities. The scientific bases of the three sets of proposed operating criteria are evaluated in the present report:(1) criteria proposed by the Research/Scientific Group, associated with the Glen Canyon Environmental Studies (GCES); (2) criteria proposed state and federal officials charged with managing downstream resources; and (3) test criteria imposed from July 1991, to November 1991. Data from Phase 1 of the GCES and other sources established that the targeted natural resources are affected by dam operations, but the specific interim criteria chosen were not supported by any existing studies. It is unlikely that irreversible changes to any of the resources would occur over the interim period if historical operating criteria remained in place. It is likely that adoption of any of the sets of proposed interim operating criteria would reduce the levels of sediment transport and erosion below Glen Canyon Dam; however, these interim criteria could result in some adverse effects, including the accumulation of debris at tributary mouths, a shift of new high-water-zone vegetation into more flood-prone areas, and further declines in vegetation in the old high water zone.

  18. Compliance Monitoring of Subyearling Chinook Salmon Survival and Passage at The Dalles Dam, Summer 2012

    SciTech Connect (OSTI)

    Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Johnson, Gary E.

    2013-05-01T23:59:59.000Z

    The purpose of this compliance study was to estimate dam passage survival of subyearling Chinook salmon at The Dalles Dam during summer 2012. Under the 2008 Federal Columbia River Power System Biological Opinion, dam passage survival is required to be greater than or equal to 0.93 and estimated with a standard error (SE) less than or equal to 0.015. The study also estimated survival from the forebay 2 km upstream of the dam and through the tailrace to 2 km downstream of the dam, forebay residence time, tailrace egress time, spill passage efficiency (SPE), and fish passage efficiency (FPE), as required by the 2008 Columbia Basin Fish Accords.

  19. Simulation of turbulent flames relevant to spark-ignition engines

    E-Print Network [OSTI]

    Ahmed, Irufan

    2014-04-29T23:59:59.000Z

    -premixed. In premixed flames, fuel and oxidiser are mixed homo- geneously before combustion. Lean-burn gas turbines for power generation and spark-ignition (SI) IC engines are typical examples of this type of combustion. In non-premixed or ‘diffusion flames’, the fuel... and oxidiser are transported sep- arately into the reaction zones by diffusion. Aero-engine gas turbines and diesel engines are typical examples of non-premixed combustion. It is often the case in practical systems that fuel and air is not completely mixed...

  20. Scalar dissipation rate based flamelet modelling of turbulent premixed flames

    E-Print Network [OSTI]

    Kolla, Hemanth

    2010-03-16T23:59:59.000Z

    closure for two mixtures: stoichiometric methane–air with K = 1.0 (•) and lean propane–air with KLe = 1.0 (?). The experimental data of Abdel- Gayed et al. (1987) for K = 1.0 are also shown (?). . . . . . . . . 111 7.9 The comparisons of flame speeds... closure for two mixtures: stoichiometric methane–air with K = 1.0 (•) and lean propane–air with KLe = 1.0 (?). The experimental data of Abdel- Gayed et al. (1987) for K = 1.0 are also shown (?). . . . . . . . . 111 7.9 The comparisons of flame speeds...

  1. INVESTIGATION ON THE FLAME EXTINCTION LIMIT OF FUEL BLENDS

    SciTech Connect (OSTI)

    Ahsan R. Choudhuri

    2005-02-01T23:59:59.000Z

    Lean flame extinction limits of binary fuel mixtures of methane (CH{sub 4}), propane (C{sub 3}H{sub 8}), and ethane (C{sub 2}H{sub 6}) were measured using a twin-flame counter-flow burner. Experiments were conducted to generate an extinction equivalence ratio vs. global stretch rate plot and an extrapolation method was used to calculate the equivalence ratio corresponding to an experimentally unattainable zero-stretch condition. The foregoing gases were selected because they are the primary constitutes of natural gas, which is the primary focus of the present study. To validate the experimental setup and methodology, the flame extinction limit of pure fuels at zero stretch conditions were also estimated and compared with published values. The lean flame extinction limits of methane (f{sub ext} = 4.6%) and propane (f{sub ext} = 2.25%) flames measured in the present study agreed with the values reported in the literature. It was observed that the flame extinction limit of fuel blends have a polynomial relation with the concentration of component fuels in the mixture. This behavior contradicts with the commonly used linear Le Chatelier's approximation. The experimentally determined polynomial relations between the flame extinction limits of fuel blends (i.e. methane-propane and methane-ethane) and methane concentration are as follows: (1) Methane-Propane--%f{sub ext} = (1.05 x 10{sup -9}) f{sup 5}-(1.3644 x 10{sup -7}) f{sup 4}+(6.40299 x 10{sup -6}) f{sup 3}-(1.2108459 x 10{sup -4}) f{sup 2}+(2.87305329 x 10{sup -3}) f+2.2483; (2) Methane-Ethane--%f{sub ext} = (2.1 x 10{sup -9})f{sup 5}-(3.5752 x 10{sup -7}) f{sup 4}+(2.095425 x 10{sup -5}) f{sup 3}-(5.037353 x 10{sup -4}) f{sup 2} + 6.08980409 f + 2.8923. Where f{sub ext} is the extinction limits of methane-propane and methane-ethane fuel blends, and f is the concentration (% volume) of methane in the fuel mixture. The relations were obtained by fitting fifth order curve (polynomial regression) to experimentally measured extinction limits at different mixture conditions. To extend the study to a commercial fuel, the flame extinction limit for Birmingham natural gas (a blend of 95% methane, 5% ethane and 5% nitrogen) was experimentally determined and was found to be 3.62% fuel in the air-fuel mixture.

  2. Spatial resolution of temperature and chemical species in a flame

    E-Print Network [OSTI]

    Albahadily, Fakhrildeen Niema

    1984-01-01T23:59:59.000Z

    by Winefordner et al. (51). AE . /k A. g. I. B. ln ~ + ln ? + 1n? 1 A. g. i B. (36) where: subscript i = the level excited by the source subscript j = the thermally assisted level flame temperature AE . . ij the difference in energy between i and j.... Schweikert (Member) Abdel-Kad Ayou (Memb ) Vaneica . Y ng (Member) May 1984 ABSTRACT Spatial Resolution of Temperature and Chemical Species in a Flame. (May 1984) Fakhrildeen Niema Albahadily, B. S. , University of Basrah/Iraq Chairman of Advisory...

  3. Enlargement of concrete blocks of arch dams with allowance of the formation of radial thermal cracks

    SciTech Connect (OSTI)

    Verbetskii, G.P.; Chogovadze, G.I.; Daneliya, A.I.

    1988-04-01T23:59:59.000Z

    Considerable acceleration of the construction of arch dams with the use of highly productive continuous concreting mechanisms is possible with enlargement of the blocks and allowance of the formation of thermal radial cracks in them. A theoretical analysis and the results of on-site observations show that under the effect of the hydrostatic head of water, radial joints and cracks in compressed zones of an arch dam close and the dam in these zones works as a solid dam. Thermal cracking in concrete blocks of arch dams enlarged in plan should be controlled by making radial notches to concentrate tensile stresses providing the formation of radial cracks at prescribed places and through the usual methods of thermal regulation. The block size along the face of an arch dam is then no longer limited by the condition of crack resistance but is determined by the rate of concreting. The technical and economic effects from concreting arch dams are cited.

  4. Effect of Blending on High-Pressure Laminar Flame Speed Measurements, Markstein Lengths, and Flame Stability of Hydrocarbons

    E-Print Network [OSTI]

    Lowry, William Baugh

    2012-02-14T23:59:59.000Z

    . Hydrocarbon blends of methane, ethane, and propane make up a large portion of natural gas and it has been shown that dimethyl ether can be used as a supplement or in its pure form for gas turbine combustion. Because of this, a fundamental understanding... include the flame speeds for binary blends of methane, ethane, propane, and dimethyl ether performed at elevated pressures, up to 10-atm initial pressure, using a spherically expanding flame in a constant-volume vessel. Also included in this thesis is a...

  5. Small-scale Interaction of Turbulence with Thermonuclear Flames in Type Ia Supernovae

    E-Print Network [OSTI]

    J. C. Niemeyer; W. K. Bushe; G. R. Ruetsch

    1999-05-07T23:59:59.000Z

    Microscopic turbulence-flame interactions of thermonuclear fusion flames occuring in Type Ia Supernovae were studied by means of incompressible direct numerical simulations with a highly simplified flame description. The flame is treated as a single diffusive scalar field with a nonlinear source term. It is characterized by its Prandtl number, Pr << 1, and laminar flame speed, S_L. We find that if S_L ~ u', where u' is the rms amplitude of turbulent velocity fluctuations, the local flame propagation speed does not significantly deviate from S_L even in the presence of velocity fluctuations on scales below the laminar flame thickness. This result is interpreted in the context of subgrid-scale modeling of supernova explosions and the mechanism for deflagration-detonation-transitions.

  6. Extinction and near-extinction instability of non-premixed tubular flames

    SciTech Connect (OSTI)

    Hu, Shengteng; Pitz, Robert W.; Yu, Wang [Mechanical Engineering Department, Vanderbilt University, Nashville, TN 37235 (United States)

    2009-01-15T23:59:59.000Z

    Tubular non-premixed flames are formed by an opposed tubular burner, a new tool to study the effects of curvature on extinction and flame instability of non-premixed flames. Extinction of the opposed tubular flames generated by burning diluted H{sub 2}, CH{sub 4} or C{sub 3}H{sub 8} with air is investigated for both concave and convex curvature. To examine the effects of curvature on extinction, the critical fuel dilution ratios at extinction are measured at various stretch rates, initial mixture strengths and flame curvature for fuels diluted in N{sub 2}, He, Ar or CO{sub 2}. In addition, the onset conditions of the cellular instability are mapped as a function of stretch rates, initial mixture strengths, and flame curvature. For fuel mixtures with Lewis numbers much less than unity, such as H{sub 2}/N{sub 2}, concave flame curvature towards the fuel suppresses cellular instabilities. (author)

  7. Laser-induced breakdown spectroscopy measurement in methane and biodiesel flames using an ungated detector

    SciTech Connect (OSTI)

    Eseller, Kemal E.; Yueh, Fang Y.; Singh, Jagdish P

    2008-11-01T23:59:59.000Z

    Laser-induced breakdown spectroscopy (LIBS) has been applied to measure the equivalence ratio of CH4/air flames using gated detection. In this work, we have developed an ungated, miniature LIBS-based sensor for studying CH4/air and biodiesel flames. We have used this sensor to characterize the biodiesel flame. LIBS spectra of biodiesel flames were recorded with different ethanol concentrations in the biodiesel and also at different axial locations within the flame. The sensor performance was evaluated with a CH4/air flame. LIBS signals of N, O, and H from a CH4/air flame were used to determine the equivalence ratio. A linear relationship between the intensity ratio of H and O lines and the calculated equivalence ratio were obtained with this sensor.

  8. RICH METHANE PREMIXED LAMINAR FLAMES DOPED BY LIGHT UNSATURATED HYDROCARBONS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    RICH METHANE PREMIXED LAMINAR FLAMES DOPED BY LIGHT UNSATURATED HYDROCARBONS PART I: ALLENE developed in our laboratory for the reactions of C3-C4 unsaturated hydrocarbons. The main reaction pathways2007 #12;3 INTRODUCTION Soots and polyaromatic hydrocarbons (PAH), which are present in the exhaust gas

  9. Modeling of combustion noise spectrum from turbulent premixed flames

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Modeling of combustion noise spectrum from turbulent premixed flames Y. Liu, A. P. Dowling, T. D, Nantes, France 2321 #12;Turbulent combustion processes generate sound radiation due to temporal changes, this temporal correlation and its role in the modeling of combustion noise spectrum are studied by analyzing

  10. Flame Synthesis of Carbon Nanotubes Using Low Calorific Value Gases

    SciTech Connect (OSTI)

    Jorge Camacho; Mahesh Subramanya; Ahsan R. Choudhuri

    2007-03-31T23:59:59.000Z

    Nanostructures formed in diffusion flames of pure fuels [CH{sub 4}, C{sub 3}H{sub 8}, and C{sub 2}H{sub 2}] at different fuel flow rates have been analyzed. Synthesis samples have been also collected from diffusion flames of various fuel blends [H{sub 2}-CH{sub 4}, H{sub 2}-CO, H{sub 2}-C{sub 3}H{sub 8}, H{sub 2}-C{sub 2}H{sub 2}] at different combustion conditions. SEM images of particulate samples collected from H{sub 2}-CH{sub 4} diffusion flames show formation of nanostructures. However, the formation of nanostructures only occurs at a narrow window of fuel compositions (< 10% H{sub 2} concentration in the mixture) and flow conditions (Jet Exit Reynolds number Re{sub j} = 200). At higher H{sub 2} concentration and flow velocity, formation of nanostructures diminishes and H{sub 2}-CH{sub 4} flames produce amorphous carbon and soot particles.

  11. Flame/Wall interactions : laminar study of unburnt HC formation

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    and desorption by oil film, deposits in combustion chamber, flame quenching, mixture and incomplete combustion for an important part to the sources of hydrocarbon (HC) emission in a combustion chamber. The aim of this work in gasoline engine. A skeletal mechanism (29 species and 48 reactions) mimicking iso-octane combustion is used

  12. Europium-doped yttrium silicate nanophosphors prepared by flame synthesis

    E-Print Network [OSTI]

    Bernhard, Stefan

    Europium-doped yttrium silicate nanophosphors prepared by flame synthesis Xiao Qin a,*, Yiguang Ju; accepted 7 November 2006 Available online 22 December 2006 Abstract Europium-doped yttrium silicate (Y2SiO5 properties 1. Introduction Yttrium silicate (Y2SiO5) is an important luminescent host material for various

  13. Reaction zone visualisation in swirling spray n-heptane flames

    E-Print Network [OSTI]

    Yuan, R.; Kariuki, J.; Dowlut, A.; Balachandran, R.; Mastorakos, E.

    2014-06-26T23:59:59.000Z

    process and consumed in the subsequent high temperature oxidation. Formaldehyde LIF was used for autoignition of methane jets [6], methanol, ethanol and acetone spray jet flames [7,8], and diesel fuel [9-11] and n-heptane [11,12] in HCCI engines. Najm...

  14. Multiscale Simulation of Titania Nanoparticle Evolution in a Turbulent Flame

    E-Print Network [OSTI]

    Raman, Venkat

    numerous applications in drug delivery, catalysis, energy and semiconductors. Titanium dioxide (TiO2, The University of Texas, Austin, TX 78712, USA Abstract Titanium dioxide nanoparticles are manufactured in flame-based titanium dioxide synthesis are developed. A reduced chemistry mech- anism for gas-phase chemistry

  15. Structure of Partially Premixed Flames Using Detailed Chemistry Simulations

    E-Print Network [OSTI]

    Kluzek, Celine D.

    2010-10-12T23:59:59.000Z

    obtained at Sandia National Labs in 2001. The study is focused on axisymmetric laminar partially-premixed methane/air flames with varying premixture strength values of 1.8, 2.2, and 3.17. The combination of computational and experimental results is used...

  16. Investigation of polarization spectroscopy for detecting atomic hydrogen in flames

    E-Print Network [OSTI]

    Kulatilaka, Waruna Dasal

    2002-01-01T23:59:59.000Z

    . The probe beam was tuned to the single-photon 486-nm n = 2 --> n = 4 resonance of the hydrogen atom by fundamental and frequency-doubled beams from a single 486-nm dye laser were used. The probe beam was linearly polarized entering the flame...

  17. Investigation of polarization spectroscopy for detecting atomic hydrogen in flames 

    E-Print Network [OSTI]

    Kulatilaka, Waruna Dasal

    2002-01-01T23:59:59.000Z

    stabilized on near-adiabatic calibration burner (the Hencken burner). The LIPS signal was found to be nearly proportional to the square of the pump beam intensity over a wide range of flame equivalence ratios. Spectral line shapes of hydrogen 1S-4P...

  18. LES of a Hydrogen-Enriched Lean Turbulent Premixed Flame

    E-Print Network [OSTI]

    Groth, Clinton P. T.

    LES of a Hydrogen-Enriched Lean Turbulent Premixed Flame Francisco E. Hern´andez-P´erez , Clinton the observed behaviour is examined. Hydrogen-hydrocarbon fuel blends appear to be a promising option to synergistically pave the way toward pure hydrogen-based combustion systems while alleviating green-house gas

  19. atomic absorption flame: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    absorption flame First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Absorption properties of identical...

  20. Real Time Flame Monitoring of Gasifier and Injectors

    SciTech Connect (OSTI)

    Zelepouga, Serguei; Saveliev, Alexei

    2011-12-31T23:59:59.000Z

    This project is a multistage effort with the final goal to develop a practical and reliable nonintrusive gasifier injector monitor to assess burner wear and need for replacement. The project team included the National Energy Technology Laboratory (NETL), Gas Technology Institute (GTI), North Carolina State University, and ConocoPhillips. This report presents the results of the sensor development and testing initially at GTI combustion laboratory with natural gas flames, then at the Canada Energy Technology Center (CANMET), Canada in the atmospheric coal combustor as well as in the pilot scale pressurized entrained flow gasifier, and finally the sensor capabilities were demonstrated at the Pratt and Whitney Rocketdyne (PWR) Gasifier and the Wabash River Repowering plant located in West Terre Haute, IN. The initial tests demonstrated that GTI gasifier sensor technology was capable of detecting shape and rich/lean properties of natural gas air/oxygen enriched air flames. The following testing at the Vertical Combustor Research Facility (VCRF) was a logical transition step from the atmospheric natural gas flames to pressurized coal gasification environment. The results of testing with atmospheric coal flames showed that light emitted by excited OH* and CH* radicals in coal/air flames can be detected and quantified. The maximum emission intensities of OH*, CH*, and black body (char combustion) occur at different axial positions along the flame length. Therefore, the excitation rates of CH* and OH* are distinct at different stages of coal combustion and can be utilized to identify and characterize processes which occur during coal combustion such as devolatilization, char heating and burning. To accomplish the goals set for Tasks 4 and 5, GTI utilized the CANMET Pressurized Entrained Flow Gasifier (PEFG). The testing parameters of the PEFG were selected to simulate optimum gasifier operation as well as gasifier conditions normally resulting from improper operation or failed gasifier injectors. The sensor developed under previous tasks was used to assess the spectroscopic characteristics of the gasifier flame. The obtained spectral data were successfully translated into flame temperature measurements. It was also demonstrated that the reduced spectral data could be very well correlated with very important gasification process parameters such as the air/fuel and water/fuel ratio. Any of these parameters (temperature, air/fuel, and water/fuel) is sufficient to assess burner wear; however, the tested sensor was capable of monitoring all three of them plus the flame shape as functions of burner wear. This will likely be a very powerful tool which should enable significant improvements in gasifier efficiency, reliability, and availability. The sensor technology was presented to the projectâ??s industrial partner (ConocoPhillips). The partner expressed its strong interest in continuing to participate in the field validation phase of GTI's Flame Monitor Project. Finally the sensor was tested in the PWR (Pratt & Whitney Rocketdyne) gasification plant located at GTIâ??s research campus and at the ConocoPhillips industrial scale gasifier at Wabash River Indiana. The field trials of the GTI Gasifier sensor modified to withstand high temperature and pressure corrosive atmosphere of the industrial entrain flow gasifier. The project team successfully demonstrated the Gasifier Sensor system ability to monitor gasifier interior temperature maintaining unobstructed optical access for in excess of six week without any maintenance. The sensor examination upon completion of the trial revealed that the system did not sustain any damage and required minor cleanup of the optics.

  1. Turbocharger with sliding piston, and having vanes and leakage dams

    DOE Patents [OSTI]

    Roberts, Quentin (Nancy, FR); Alnega, Ahmed (Thaon Les Vosges, FR)

    2011-12-06T23:59:59.000Z

    A turbocharger having a sliding piston for regulating exhaust gas flow into the turbine wheel includes a set of first vanes mounted on a fixed first wall of the turbine nozzle and projecting axially toward an opposite second wall of the nozzle, and/or a set of second vanes mounted on the end of the piston and projecting in an opposite axial direction toward the first wall of the nozzle. For the/each set of vanes, there are leakage dams formed on the wall that is adjacent the vane tips when the piston is closed. The leakage dams are closely adjacent the vane tips and discourage exhaust gas from leaking in a generally radial direction past the vane tips as the piston just begins to open from its fully closed position.

  2. Dam constructions as sealing systems in rock salt

    SciTech Connect (OSTI)

    Engelmann, H.J.; Bollingerfehr, W.; Fischer, H. [Deutsche Gesellschaft zum Bau und Betrieb von Endlagern fuer Abfallstoffe mbH, Peine (Germany)

    1993-12-31T23:59:59.000Z

    Dam constructions represent an essential component of the multibarrier safety concept in the Federal Republic of Germany for a repository of radioactive waste in salt formations. They enhance safety during the operational phase as well as in the post operational phase of the repository. In the framework of a joint R and D-project between BGR, DBE and GSF the components of a suitable dam have been developed and will be constructed and tested in the GSF-Asse salt mine in Lower-Saxony. The aims of the investigation program, its realization and some results on the development of construction materials will be presented and discussed. Experiences gained during these tests in laboratory and in situ will be described.

  3. Lower Granite Dam Smolt Monitoring Program, 2000 Annual Report.

    SciTech Connect (OSTI)

    Morrill, Charles; Ross, Doug; Mensik, Fred

    2000-01-01T23:59:59.000Z

    The 2000 fish collection season at Lower Granite was characterized by lower than average spring flows and spill, low levels of debris, cool water temperatures, increased unclipped yearling and subyearling chinook smolts, and 8,300,546 smolts collected and transported compared to 5,882,872 in 1999. With the continued release of unclipped supplementation chinook and steelhead above Lower Granite Dam, we can no longer accurately distinguish wild chinook, steelhead, and sockeye/kokanee in the sample. Although some table titles in this report still show ''wild'' column headings, the numbers in these columns for 1999 and 2000 include wild and unclipped hatchery origin smolts. The increases over previous years reflect the increased supplementation. A total of 8,300,546 juvenile salmonids were collected at Lower Granite Dam. Of these, 187,862 fish were bypassed back to the river and 7,950,648 were transported to release sites below Bonneville Dam, 7,778,853 by barge and 171,795 by truck. A total of 151,344 salmonids were examined in daily samples. Nine research projects conducted by four agencies impacted a total of 1,361,006 smolts (16.4% of the total collection).

  4. Hydroacoustic Evaluation of Fish Passage through Bonneville Dam in 2004

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Schilt, Carl R.; Kim, Jina; Johnson, Peter N.; Hanks, Michael E.; Patterson, Deborah S.; Skalski, John R.; Hedgepeth, J

    2005-12-22T23:59:59.000Z

    The Portland District of the U.S. Army Corps of Engineers requested that the Pacific Northwest National Laboratory (PNNL) conduct fish-passage studies at Bonneville Dam in 2004. These studies support the Portland District's goal of maximizing fish-passage efficiency (FPE) and obtaining 95% survival for juvenile salmon passing Bonneville Dam. Major passage routes include 10 turbines and a sluiceway at Powerhouse 1 (B1), an 18-bay spillway, and eight turbines and a sluiceway at Powerhouse 2 (B2). In this report, we present results of four studies related to juvenile salmonid passage at Bonneville Dam. The studies were conducted between April 15 and July 15, 2004, encompassing most of the spring and summer migrations. Studies included evaluations of (1) Project fish passage efficiency and other major passage metrics, (2) B2 fish guidance efficiency and gap loss, (3) smolt approach and fate at the B2 Corner Collector (B2CC), and (4) B2 vertical barrier screen head differential.

  5. Overview of Rocky Mountain Region's Capital Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Casper Riverton Wyodak Ft. St. Vrain Ault Story Flaming Gorge Lost Canyon Hesperus Lamar (DC Terminal) Hayden Meeker Rifle Bonanza Vernal Osage Lange Spence Platte Montrose...

  6. Environmental effects of dredging. The value of wing dams for freshwater mussels

    SciTech Connect (OSTI)

    Miller, A.C.; Whiting, R.

    1988-11-01T23:59:59.000Z

    This note provides information on the value of wing dams, which reduce dredging requirements in large rivers, for freshwater mussels. Wing dams are longitudinal rock-rubble structures placed in waterways to develop and stabilize channels. Wing dams constrict low flows, which decreases maintenance dredging requirements (Shields 1983). These structures are usually oriented obliquely or at 90 deg to the current. Sediment deposition usually occurs between wing dams where current velocity is reduced relative to that in the unprotected main channel. Wing dams create quiescent areas that are similar to naturally occurring lentic habitats during normal and low flow (Beckett et al. 1983). In addition, wing dams themselves are a coarse-grained substrate used by aquatic insects and fishes (Conner, Pennington, and Bosley 1983; Pennington, Baker, and Bond 1983; and Shields 1983).

  7. Soot microstructure in steady and flickering laminar methane/air diffusion flames

    SciTech Connect (OSTI)

    Zhang, J.; Megaridis, C.M. [Univ. of Illinois, Chicago, IL (United States). Dept. of Mechanical Engineering

    1998-03-01T23:59:59.000Z

    An experimental investigation is presented to identify the mechanisms responsible for the enhanced sooting behavior of strongly flickering methane/air jet diffusion flames when compared to their steady counterparts. The work extends the implementation of thermophoretic sampling in flickering, co-flow, laminar, diffusion flames. Acoustic forcing of the fuel flow rate is used to phase lock the periodic flame flicker close to the natural flicker frequency ({approximately} 10 Hz for a burner diameter of {approximately} 1 cm). Soot primary sizes, determined as functions of flame coordinates, indicate that the largest soot primary units in strongly flickering methane/air flames are larger by {approximately} 60% than those measured in steady flames with the same mean reactant flow rates. The primary particle size measurements, when combined with the soot volume fractions reported by other investigators, indicate that soot surface areas in the flickering flame are three to four times larger than those under steady conditions. These results, along with the fact that residence times in the flickering flame are twice as long as those in the steady flame, suggest that specific soot surface growth rates under unsteady combustion conditions can be similar or even lower than those in the corresponding steady flames. Finally, the number of densities of soot primaries in flickering flames are found to be higher by 30--50% than those in steady flames, thus suggesting stronger and/or extended soot inception mechanisms under flickering conditions. The combination of longer flow residence times and greater population of incipient soot particles in flickering flames appears to be primarily responsible for the higher sooting propensity of methane under laminar unsteady combustion conditions.

  8. A not-so-funny thing happened on the way to relicensing the Edwards Dam

    SciTech Connect (OSTI)

    Ayer, F.J. [Devine & Tarbell, Inc., Portland, ME (United States); Isaacson, M. [Edwards Manufacturing Co., Lisbon Falls, ME (United States)

    1995-12-31T23:59:59.000Z

    What started out as a seemingly straightforward and simple exercise, obtaining a new FERC license for the Edwards Dam in Augusta, Maine, turned out to be anything but straightforward and far from simple. This article tells the story of one of the more interesting and possibly precedent setting cases in the {open_quotes}class of 93{close_quotes} and is presented in three sections: (1) the history of the Edwards Dam and the FERC regulatory process through the spring of 1995; (2) Edwards` response to the dam removal campaign; and (3) recommendations for FERC licensees threatened by dam removal during relicensing.

  9. Environmental Constraints on Hydropower: An Ex Post Benefit-Cost Analysis of Dam

    E-Print Network [OSTI]

    Kotchen, Matthew J.

    Environmental Constraints on Hydropower: An Ex Post Benefit-Cost Analysis of Dam Relicensing Consumers Protection Act (1986), which instructs federal regulators to ``balance'' hydropower

  10. FLAME facility: The effect of obstacles and transverse venting on flame acceleration and transition on detonation for hydrogen-air mixtures at large scale

    SciTech Connect (OSTI)

    Sherman, M.P.; Tieszen, S.R.; Benedick, W.B.

    1989-04-01T23:59:59.000Z

    This report describes research on flame acceleration and deflagration-to-detonation transition (DDT) for hydrogen-air mixtures carried out in the FLAME facility, and describes its relevance to nuclear reactor safety. Flame acceleration and DDT can generate high peak pressures that may cause failure of containment. FLAME is a large rectangular channel 30.5 m long, 2.44 m high, and 1.83 m wide. It is closed on the ignition end and open on the far end. The three test variables were hydrogen mole fraction (12--30%), degree of transverse venting (by moving steel top plates---0%, 13%, and 50%), and the absence or presence of certain obstacles in the channel (zero or 33% blockage ratio). The most important variable was the hydrogen mole fraction. The presence of the obstacles tested greatly increased the flame speeds, overpressures, and tendency for DDT compared to similar tests without obstacles. Different obstacle configurations could have greater or lesser effects on flame acceleration and DDT. Large degrees of transverse venting reduced the flame speeds, overpressures, and possibility of DDT. For small degrees of transverse venting (13% top venting), the flame speeds and overpressures were higher than for no transverse venting with reactive mixtures (>18% H/sub 2/), but they were lower with leaner mixtures. The effect of the turbulence generated by the flow out the vents on increasing flame speed can be larger than the effect of venting gas out of the channel and hence reducing the overpressure. With no obstacles and 50% top venting, the flame speeds and overpressures were low, and there was no DDT. For all other cases, DDT was observed above some threshold hydrogen concentration. DDT was obtained at 15% H/sub 2/ with obstacles and no transverse venting. 67 refs., 62 figs.

  11. On the small-scale stability of thermonuclear flames in Type Ia supernovae

    E-Print Network [OSTI]

    F. K. Roepke; J. C. Niemeyer; W. Hillebrandt

    2003-05-02T23:59:59.000Z

    We present a numerical model which allows us to investigate thermonuclear flames in Type Ia supernova explosions. The model is based on a finite-volume explicit hydrodynamics solver employing PPM. Using the level-set technique combined with in-cell reconstruction and flux-splitting schemes we are able to describe the flame in the discontinuity approximation. We apply our implementation to flame propagation in Chandrasekhar-mass Type Ia supernova models. In particular we concentrate on intermediate scales between the flame width and the Gibson-scale, where the burning front is subject to the Landau-Darrieus instability. We are able to reproduce the theoretical prediction on the growth rates of perturbations in the linear regime and observe the stabilization of the flame in a cellular shape. The increase of the mean burning velocity due to the enlarged flame surface is measured. Results of our simulation are in agreement with semianalytical studies.

  12. Fuel control for gas turbine with continuous pilot flame

    DOE Patents [OSTI]

    Swick, Robert M. (Indianapolis, IN)

    1983-01-01T23:59:59.000Z

    An improved fuel control for a gas turbine engine having a continuous pilot flame and a fuel distribution system including a pump drawing fuel from a source and supplying a line to the main fuel nozzle of the engine, the improvement being a control loop between the pump outlet and the pump inlet to bypass fuel, an electronically controlled throttle valve to restrict flow in the control loop when main nozzle demand exists and to permit substantially unrestricted flow without main nozzle demand, a minimum flow valve in the control loop downstream of the throttle valve to maintain a minimum pressure in the loop ahead of the flow valve, a branch tube from the pilot flame nozzle to the control loop between the throttle valve and the minimum flow valve, an orifice in the branch tube, and a feedback tube from the branch tube downstream of the orifice to the minimum flow valve, the minimum flow valve being operative to maintain a substantially constant pressure differential across the orifice to maintain constant fuel flow to the pilot flame nozzle.

  13. Fuel effects on flame lift-off under diesel conditions

    SciTech Connect (OSTI)

    Persson, Helena; Andersson, Oeivind; Egnell, Rolf [Lund University (Sweden). Dept. of Energy Sciences

    2011-01-15T23:59:59.000Z

    An apparent relation between the lift-off length under diesel conditions and the ignition quality of a fuel has previously been reported. To cast light on the underlying mechanism, the current study aims to separate flame lift-off effects of the chemical ignition delay from those of other fuel properties under diesel conditions. Flame lift-off was measured in an optical diesel engine by high-speed video imaging of OH-chemiluminescence. Fuel and ambient-gas properties were varied during the experiment. Only a weak correlation was found between ignition delay and lift-off length. The data indicate that this correlation is due to a common, stronger correlation with the ambient oxygen concentration. The chemical ignition delay and the fuel type had similar, weak effects on the lift-off length. A recently proposed mechanism for lift-off stabilization was used to interpret the results. It assumes that reactants approaching the lift-off position of the jet are mixed with high-temperature products found along the edges of the flame, which trigger autoignition. In this picture, the fuel effect is most likely due to differences in the amount of mixing with high-temperature products that is required for autoignition. In the current experiment, all lift-off effects seem to arise from variations in the reactant and product temperatures, induced by fuel and ambient properties. (author)

  14. Fabrication of functional nanomaterials using flame assisted spray pyrolysis

    SciTech Connect (OSTI)

    Purwanto, Agus, E-mail: aguspur@uns.ac.id [Chemical Engineering Department, Faculty of Engineering, Sebelas Maret University, Surakarta 632112 (Indonesia)

    2014-02-24T23:59:59.000Z

    Flame assisted spray pyrolysis (FASP) is a class of synthesis method for nanomaterials fabrication. The ability to control nanomaterials characteristics and easy to be-scaled up are the main features of FASP. The crystallinity and particles size of the prepared nanomaterials can be easily controlled by variation of fuel flow rate. The precursor concentration, carrier gas flow rate, and carrier gas can be also used to control the prepared nanomaterials. Energy related nanomaterials preparation uses as the example case in FASP application. These material are yttrium aluminum garnet (YAG:Ce) and tungsten oxide (WO{sub 3}). It needs strategies to produce these materials into nano-sized order. YAG:Ce nanoparticles only can be synthesized by FASP using the urea addition. The decomposition of urea under high temperature of flame promotes the breakage of YAG:Ce particles into nanoparticles. In the preparation of WO{sub 3}, the high temperature flame can be used to gasify WO{sub 3} solid material. As a result, WO{sub 3} nanoparticles can be prepared easily. Generally, to produce nanoparticles via FASP method, the boiling point of the material is important to determine the strategy which will be used.

  15. Flame propagation enhancement by plasma excitation of oxygen. Part I: Effects of O{sub 3}

    SciTech Connect (OSTI)

    Ombrello, Timothy; Won, Sang Hee; Ju, Yiguang [Department of Mechanical and Aerospace Engineering, Engineering Quadrangle, Olden Street, Princeton, NJ 08544 (United States); Williams, Skip [Air Force Research Laboratory, Propulsion Directorate, 1950 Fifth Street, Wright-Patterson AFB, OH 45433 (United States)

    2010-10-15T23:59:59.000Z

    The thermal and kinetic effects of O{sub 3} on flame propagation were investigated experimentally and numerically by using C{sub 3}H{sub 8}/O{sub 2}/N{sub 2} laminar lifted flames. Ozone produced by a dielectric barrier plasma discharge was isolated and measured quantitatively by using absorption spectroscopy. Significant kinetic enhancement by O{sub 3} was observed by comparing flame stabilization locations with and without O{sub 3} production. Experiments at atmospheric pressures showed an 8% enhancement in the flame propagation speed for 1260 ppm of O{sub 3} addition to the O{sub 2}/N{sub 2} oxidizer. Numerical simulations showed that the O{sub 3} decomposition and reaction with H early in the pre-heat zone of the flame produced O and OH, respectively, from which the O reacted rapidly with C{sub 3}H{sub 8} and produced additional OH. The subsequent reaction of OH with the fuel and fuel fragments, such as CH{sub 2}O, provided chemical heat release at lower temperatures to enhance the flame propagation speed. It was shown that the kinetic effect on flame propagation enhancement by O{sub 3} reaching the pre-heat zone of the flame for early oxidation of fuel was much greater than that by the thermal effect from the energy contained within O{sub 3}. For non-premixed laminar lifted flames, the kinetic enhancement by O{sub 3} also induced changes to the hydrodynamics at the flame front which provided additional enhancement of the flame propagation speed. The present results will have a direct impact on the development of detailed plasma-flame kinetic mechanisms and provided a foundation for the study of combustion enhancement by O{sub 2}(a{sup 1}{delta}{sub g}) in part II of this investigation. (author)

  16. Hydroacoustic Evaluation of Fish Passage Through Bonneville Dam in 2005

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Zimmerman, Shon A.; Hughes, James S.; Bouchard, Kyle E.; Fischer, Eric S.; Schilt, Carl R.; Hanks, Michael E.; Kim, Jina; Skalski, John R.; Hedgepeth, J.; Nagy, William T.

    2006-12-04T23:59:59.000Z

    The Portland District of the U.S. Army Corps of Engineers requested that the Pacific Northwest National Laboratory (PNNL) conduct fish-passage studies at Bonneville Dam in 2005. These studies support the Portland District's goal of maximizing fish-passage efficiency (FPE) and obtaining 95% survival for juvenile salmon passing Bonneville Dam. Major passage routes include 10 turbines and a sluiceway at Powerhouse 1 (B1), an 18-bay spillway, and eight turbines and a sluiceway at Powerhouse 2 (B2). In this report, we present results of two studies related to juvenile salmonid passage at Bonneville Dam. The studies were conducted between April 16 and July 15, 2005, encompassing most of the spring and summer migrations. Studies included evaluations of (1) Project fish passage efficiency and other major passage metrics, and (2) smolt approach and fate at B1 Sluiceway Outlet 3C from the B1 forebay. Some of the large appendices are only presented on the compact disk (CD) that accompanies the final report. Examples include six large comma-separated-variable (.CSV) files of hourly fish passage, hourly variances, and Project operations for spring and summer from Appendix E, and large Audio Video Interleave (AVI) files with DIDSON-movie clips of the area upstream of B1 Sluiceway Outlet 3C (Appendix H). Those video clips show smolts approaching the outlet, predators feeding on smolts, and vortices that sometimes entrained approaching smolts into turbines. The CD also includes Adobe Acrobat Portable Document Files (PDF) of the entire report and appendices.

  17. EIS-0352: U.S. 93 Hoover Dam Bypass Project

    Broader source: Energy.gov [DOE]

    The Western Area Power Administration (WAPA) served as a cooperating agency for this Federal Highway Administration Environmental Impact Statement (EIS) due to WAPA’s role in the relocation of several transmission lines. The Federal Highway Administration (FHWA) prepared an Environmental Impact Statement (EIS) for construction of a new segment of U.S. Highway 93 for the purpose of improving congestion and hazardous vehicle/pedestrian conflicts where the highway crosses the Colorado River over Hoover Dam. As a cooperating agency for the EIS, WAPA proposed modifications to its transmission system and facilities to accommodate the construction of the new highway and bridge spanning the Colorado River.

  18. City of Coulee Dam, Washington (Utility Company) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnual Siteof EnergyInnovationin Urban Transport |City ofBlueChappell,City ofCityCoulee Dam,

  19. The speciation and morphology of chromium oxide nanoparticles in a diffusion flame

    E-Print Network [OSTI]

    Guo, B; Kennedy, Ian M

    2004-01-01T23:59:59.000Z

    Shaffer et al. , 2001).Thermophoretic sampling was also usedwithin the flame. The thermophoretic sampling device wasbe discussed shortly. The thermophoretic drift velocity of

  20. Numerical and experimental studies of ethanol flames and autoignition theory for higher alkanes

    E-Print Network [OSTI]

    Saxena, Priyank

    2007-01-01T23:59:59.000Z

    was used to vaporize ethanol fuel. The vaporizer wasmixture of the evaporated ethanol fuel and the nitrogen gas.premixed flames of ethanol and other fuels for comparison

  1. Numerical study of premixed twin edge flames in a counterflow field

    SciTech Connect (OSTI)

    Cho, Seong-Jin; Takita, Kenichi [Department of Aeronautics and Space Engineering, Tohoku University, Aramaki, Sendai 980-8579 (Japan)

    2006-01-01T23:59:59.000Z

    Characteristics of premixed edge flames established in a counterflow field with a stretch-rate gradient were numerically investigated by solving three-dimensional governing equations with detailed chemistry in the general curvilinear coordinates system. Local mole fractions of radicals, such as OH or CH, at the flame edge of a CH{sub 4}/air mixture were found to be larger than those in other parts of the flame. On the other hand, local mole fractions of radicals in the flame edge of a C{sub 3}H{sub 8}/air mixture were smaller than those in other parts. These numerical results agreed well with the experimental results of the present authors. Moreover, it was elucidated that two flame edges of twin counterflow flames did not merge at the edge even in the case of the CH{sub 4}/air mixture. The ratio of the local stretch rate at the flame edge to the extinction stretch rate for planar twin flames with the same equivalence ratio was 0.6 for the CH{sub 4}/air mixture and 0.7 for the C{sub 3}H{sub 8}/air mixture. These numerical results also agreed with results of the past experiments. Moreover, as for relatively low stretch-rate gradients, the stretch-rate gradient had no strong influence on the characteristics of the edge flames.

  2. Turbulent Flame Speeds and NOx Kinetics of HHC Fuels with Contaminants and High Dilution Levels

    SciTech Connect (OSTI)

    Peterson, Eric; Krejci, Michael; Mathieu, Olivier; Vissotski, Andrew; Ravi, Sankat; Plichta, Drew; Sikes, Travis; Levacque, Anthony; Camou, Alejandro; Aul, Christopher

    2013-09-30T23:59:59.000Z

    This final report documents the technical results of the 3-year project entitled, “Turbulent Flame Speeds and NOx Kinetics of HHC Fuels with Contaminants and High Dilution Levels,” funded under the NETL of DOE. The research was conducted under six main tasks: 1) program management and planning; 2) turbulent flame speed measurements of syngas mixtures; 3) laminar flame speed measurements with diluents; 4) NOx mechanism validation experiments; 5) fundamental NOx kinetics; and 6) the effect of impurities on NOx kinetics. Experiments were performed using primary constant-volume vessels for laminar and turbulent flame speeds and shock tubes for ignition delay times and species concentrations. In addition to the existing shock- tube and flame speed facilities, a new capability in measuring turbulent flame speeds was developed under this grant. Other highlights include an improved NOx kinetics mechanism; a database on syngas blends for real fuel mixtures with and without impurities; an improved hydrogen sulfide mechanism; an improved ammonia kintics mechanism; laminar flame speed data at high pressures with water addition; and the development of an inexpensive absorption spectroscopy diagnostic for shock-tube measurements of OH time histories. The Project Results for this work can be divided into 13 major sections, which form the basis of this report. These 13 topics are divided into the five areas: 1) laminar flame speeds; 2) Nitrogen Oxide and Ammonia chemical kinetics; 3) syngas impurities chemical kinetics; 4) turbulent flame speeds; and 5) OH absorption measurements for chemical kinetics.

  3. Numerical and experimental studies of ethanol flames and autoignition theory for higher alkanes

    E-Print Network [OSTI]

    Saxena, Priyank

    2007-01-01T23:59:59.000Z

    ethanol flames”, ASME TURBO EXPO 2006: Power for Land, Seaof GT2006, ASME Turbo Expo 2006: Power for Land, Sea and

  4. Direct numerical simulations of type Ia supernovae flames I: The landau-darrieus instability

    E-Print Network [OSTI]

    Bell, J.B.; Day, M.S.; Rendleman, C.A.; Woosley, S.E.; Zingale, M.

    2003-01-01T23:59:59.000Z

    Simulations of Type Ia Supernovae Flames I: The Landau-Subject headings: supernovae: general — white dwarfs —could occur in Type Ia supernovae (Niemeyer & Woosley 1997),

  5. Direct numerical simulations of type Ia supernovae flames II: The rayleigh-taylor instability

    E-Print Network [OSTI]

    Bell, J.B.; Day, M.S.; Rendleman, C.A.; Woosley, S.E.; Zingale, M.

    2004-01-01T23:59:59.000Z

    Weaver, T. A. 1994, in Supernovae, Les Houches, Session LIV,Simulations of Type Ia Supernovae Flames II: The Rayleigh-Subject headings: supernovae: general — white dwarfs —

  6. Flame front disturbance induced by a weak pressure wave

    SciTech Connect (OSTI)

    Dobashi, Ritsu; Hirano, Toshisuke; Tsuruda, Takashi [Univ. of Tokyo (Japan)

    1994-12-31T23:59:59.000Z

    An experimental study has been conducted on the effect of unburned mixture properties on flame front disturbance induced by acceleration. Experiments were performed using a rectangular combustion chamber of 80 x 80 x 440 mm. The flame front disturbance was observed in two different directions by high-speed schlieren photography. Mixtures used are of three different concentrations (C = 0.8, 1.0, and 1.25) of methane/air and two different concentrations (C = 1.0 and 1.5) of propane/air. For the methane/air mixture of C = 1.0, experiments were performed at three different initial pressures (P{sub i} = 50, 70, and 101 kPa). The observed disturbance was of a very fine structure of circular spikes, which penetrated into the burned gas. The scales of disturbance were measured and indicated to be in the range of 1.7--4.0 mm. The circular spike shape is a typical structure induced by accelerating the flame front where the density changes steeply. However, the shape of the disturbance observed for a rich propane/air mixture was not of circular spikes but of a net of ridges. For the rich propane/air mixture, the effect by preferential diffusion was remarkable and the disturbance of a different structure was generated. For the methane/air mixtures, the scale was the smallest at C = 1.0 and larger at C = 0.8 and 1.25. The scale for the propane/air mixture of C = 1.0 was slightly larger than that in the methane/air mixture of C = 1.0. The scale became larger with the decrease of the initial pressure. The measure scales were compared with the preheat zone thicknesses of corresponding flames. It was shown that the scale is closely related with the flame thickness. The scale of disturbance is found to be about 15 times as large as the preheat zone thickness.

  7. Water quality and sedimentation implications of installing a hydroelectric dam on the Río Baker in Chilean Patagonia

    E-Print Network [OSTI]

    Leandro, Gianna Dee

    2009-01-01T23:59:59.000Z

    HidroAysen, a Chilean corporation operated by energy giant Endesa, has proposed to build two hydroelectric dams on the Rio Baker in the Aysin Region of Chilean Patagonia. The proposed dams have been met with a variety of ...

  8. European Working Groupe on Internal Erorion in embankment dams April 12th to 14th 2010, Granada, Spain

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    European Working Groupe on Internal Erorion in embankment dams April 12th to 14th 2010, Granada Working Groupe on Internal Erosion in embankment dams, Granada : Spain (2010)" #12;

  9. Tension applied through the Dam1 complex promotes microtubule elongation: a direct mechanism for length control in

    E-Print Network [OSTI]

    Davis, Trisha N.

    Tension applied through the Dam1 complex promotes microtubule elongation: a direct mechanism tension to a model of the kinetochore-microtubule interface composed of the yeast Dam1 complex11-13 bound

  10. Combustion-derived flame generated ultrafine soot generates reactive oxygen species and activates Nrf2 antioxidants differently in neonatal and adult rat lungs

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    article as: Chan et al. : Combustion-derived flame generatedRESEARCH Open Access Combustion-derived flame generated6]. Vehicle exhaust from combustion of gasoline, diesel and

  11. Geochemical Evidence for an Eolian Sand Dam across the North and South Platte Rivers in Nebraska

    E-Print Network [OSTI]

    Loope, David B.

    Geochemical Evidence for an Eolian Sand Dam across the North and South Platte Rivers in Nebraska that the Nebraska Sand Hills once migrated across the North and South Platte rivers and dammed the largest tributary of the South Platte River, have compositions intermediate between the Nebraska Sand Hills (quartz

  12. Uncertainty analysis of river flooding and dam failure risks using local sensitivity computations.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Uncertainty analysis of river flooding and dam failure risks using local sensitivity computations) for uncertainty analysis with respect to two major types of risk in river hydrodynamics: flash flood and dam failure. LSA is com- pared to a Global Uncertainty Analysis (GUA) consisting in running Monte Carlo

  13. Research Report Long lasting effects of rearing by an ethanol-consuming dam

    E-Print Network [OSTI]

    Galef Jr., Bennett G.

    Research Report Long lasting effects of rearing by an ethanol-consuming dam on voluntary ethanol rats as subjects, we examined effects of exposure during weaning to a dam consuming ethanol on adolescents' later affinity for ethanol. In a preliminary experiment, we offered rat pups a choice between 8

  14. A. Reservoir Effects of Stream Channels DAM IMPACTS ON AND RESTORATION OF AN ALLUVIAL RIVER

    E-Print Network [OSTI]

    Julien, Pierre Y.

    A. Reservoir Effects of Stream Channels DAM IMPACTS ON AND RESTORATION OF AN ALLUVIAL RIVER ­ RIO, and restoration efforts. Cochiti Dam was constructed on the main stem of the Rio Grande in 1973 for flood control minnow. Recent restoration strategies include removal of non-native riparian vegetation, mechanical

  15. Mangla Dam Raising Project (Pakistan): General Review and Socio-Spatial Impact Assessment

    E-Print Network [OSTI]

    Boyer, Edmond

    Mangla Dam Raising Project (Pakistan): General Review and Socio-Spatial Impact Assessment Saheeb, National University of Sciences and Technology, Islamabad-44000, Pakistan saheebk@ceme.nust.edu.pk Abstract. INTRODUCTION Pakistan has recently successfully completed the raising of Mangla dam, a major water works system

  16. Effective mitigation of debris flows at Lemon Dam, La Plata County, Colorado

    E-Print Network [OSTI]

    Effective mitigation of debris flows at Lemon Dam, La Plata County, Colorado Victor G. deWolfe a May 2007 Abstract To reduce the hazards from debris flows in drainage basins burned by wildfire, erosion control measures such as construction of check dams, installation of log erosion barriers (LEBs

  17. Discrete Applied Mathematics 154 (2006) 106119 www.elsevier.com/locate/dam

    E-Print Network [OSTI]

    Lu, Mei

    2006-01-01T23:59:59.000Z

    Discrete Applied Mathematics 154 (2006) 106­119 www.elsevier.com/locate/dam Trees of extremal. Tian). 0166-218X/$ - see front matter © 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.dam.2004

  18. Discrete Applied Mathematics 155 (2007) 840856 www.elsevier.com/locate/dam

    E-Print Network [OSTI]

    Spang, Rainer

    2007-01-01T23:59:59.000Z

    Discrete Applied Mathematics 155 (2007) 840­856 www.elsevier.com/locate/dam Integer linear/$ - see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.dam.2005.09.021 #12;G.W. Klau

  19. Van Dam-Veltman-Zakharov discontinuity in topologically new massive gravity

    E-Print Network [OSTI]

    Yun Soo Myung

    2012-12-31T23:59:59.000Z

    We study van Dam-Veltman-Zakharov discontinuity in the topologically new massive gravity (TNMG). The reduction from 2 degrees of freedom to one is interpreted as van Dam-Veltman-Zakharov discontinuity appeared when going from anti-de Sitter spacetime to Minkowski spacetime in the linearized TNMG.

  20. Discrete Applied Mathematics 157 (2009) 982990 www.elsevier.com/locate/dam

    E-Print Network [OSTI]

    Lai, Hong-jian

    2009-01-01T23:59:59.000Z

    Discrete Applied Mathematics 157 (2009) 982­990 www.elsevier.com/locate/dam Hamiltonian-218X/$ - see front matter c 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.dam.2008.02.005 #12;H

  1. Discrete Applied Mathematics 155 (2007) 831839 www.elsevier.com/locate/dam

    E-Print Network [OSTI]

    Roth, Frederick

    2007-01-01T23:59:59.000Z

    Discrete Applied Mathematics 155 (2007) 831­839 www.elsevier.com/locate/dam Binary templates Elsevier B.V. All rights reserved. doi:10.1016/j.dam.2005.07.015 #12;832 O.D. King, P. Gaborit

  2. Continuous Monitoring of an Ice Sheet in a Reservoir Upstream of Beaumont Dam, Canada

    E-Print Network [OSTI]

    Santerre, Rock

    conducted at the Beaumont hydroelectric dam owned and operated by Hydro-Québec. This power plant has six find- ings will help to harmonize the different standards that are used to manage hydroelectric power considerable economic savings related to minimizing production losses, optimizing dam reinforcement works

  3. ADtrees for Sequential Data and N-gram Counting Rob Van Dam and Dan Ventura

    E-Print Network [OSTI]

    Martinez, Tony R.

    ADtrees for Sequential Data and N-gram Counting Rob Van Dam and Dan Ventura Abstract-- We consider Ventura are with the Department of Com- puter Science, Brigham Young University, Provo, UT 84602 (email: rvan- dam00@gmail.com, ventura@cs.byu.edu) the best smoothing techniques utilize some (often linear

  4. PREDICTION OF TOTAL DISSOLVED GAS EXCHANGE AT HYDROPOWER DAMS

    SciTech Connect (OSTI)

    Hadjerioua, Boualem [ORNL; Pasha, MD Fayzul K [ORNL; Stewart, Kevin M [ORNL; Bender, Merlynn [Bureau of Reclamation; Schneider, Michael L. [U.S. Army Corps of Engineers

    2012-07-01T23:59:59.000Z

    Total dissolved gas (TDG) supersaturation in waters released at hydropower dams can cause gas bubble trauma in fisheries resulting in physical injuries and eyeball protrusion that can lead to mortality. Elevated TDG pressures in hydropower releases are generally caused by the entrainment of air in spillway releases and the subsequent exchange of atmospheric gasses into solution during passage through the stilling basin. The network of dams throughout the Columbia River Basin (CRB) are managed for irrigation, hydropower production, flood control, navigation, and fish passage that frequently result in both voluntary and involuntary spillway releases. These dam operations are constrained by state and federal water quality standards for TDG saturation which balance the benefits of spillway operations designed for Endangered Species Act (ESA)-listed fisheries versus the degradation to water quality as defined by TDG saturation. In the 1970s, the United States Environmental Protection Agency (USEPA), under the federal Clean Water Act (Section 303(d)), established a criterion not to exceed the TDG saturation level of 110% in order to protect freshwater and marine aquatic life. The states of Washington and Oregon have adopted special water quality standards for TDG saturation in the tailrace and forebays of hydropower facilities on the Columbia and Snake Rivers where spillway operations support fish passage objectives. The physical processes that affect TDG exchange at hydropower facilities have been studied throughout the CRB in site-specific studies and routine water quality monitoring programs. These data have been used to quantify the relationship between project operations, structural properties, and TDG exchange. These data have also been used to develop predictive models of TDG exchange to support real-time TDG management decisions. These empirically based predictive models have been developed for specific projects and account for both the fate of spillway and powerhouse flows in the tailrace channel and resultant exchange in route to the next downstream dam. Currently, there exists a need to summarize the general finding from operational and structural TDG abatement programs conducted throughout the CRB and for the development of a generalized prediction model that pools data collected at multiple projects with similar structural attributes. A generalized TDG exchange model can be tuned to specific projects and coupled with water regulation models to allow the formulation of optimal daily water regulation schedules subject to water quality constraints for TDG supersaturation. A generalized TDG exchange model can also be applied to other hydropower dams that affect TDG pressures in tailraces and can be used to develop alternative operational and structural measures to minimize TDG generation. It is proposed to develop a methodology for predicting TDG levels downstream of hydropower facilities with similar structural properties as a function of a set of variables that affect TDG exchange; such as tailwater depth, spill discharge and pattern, project head, and entrainment of powerhouse releases. TDG data from hydropower facilities located throughout the northwest region of the United States will be used to identify relationships between TDG exchange and relevant dependent variables. Data analysis and regression techniques will be used to develop predictive TDG exchange expressions for various structural categories.

  5. Soot aerosol properties in laminar soot-emitting microgravity nonpremixed flames

    SciTech Connect (OSTI)

    Konsur, B.; Megaridis, C.M.; Griffin, D.W.

    1999-09-01T23:59:59.000Z

    The spatial distributions and morphological properties of the soot aerosol are examined experimentally in a series of 0-g laminar gas-jet nonpremixed flames. The methodology deploys round jet diffusion flames of nitrogen-diluted acetylene fuel burning in quiescent air at atmospheric pressure. Full-field laser-light extinction is utilized to determine transient soot spatial distributions within the flames. Thermophoretic sampling is employed in conjunction with transmission electron microscopy to define soot microstructure within the soot-emitting 0-g flames. The microgravity tests indicate that the 0-g flames attain a quasi-steady state roughly 0.7 s after ignition, and sustain their annular structure even beyond their luminous flame tip. The measured peak soot volume fractions show a complex dependence on burner exit conditions, and decrease in a nonlinear fashion with decreasing characteristic flow residence times. Fuel preheat by {approximately}140K appears to accelerate the formation of soot near the flame axis via enhanced field pyrolysis rates. The increased soot presence caused by the elevated fuel injection temperatures triggers higher flame radiative losses, which may account for the premature suppression of soot growth observed along the annular region of preheated-fuel flames. Electron micrographs of soot aggregates collected in 0-g reveal the presence of soot precursor particles near the symmetry axis at midflame height. The observations also verify that soot primary particle sizes are nearly uniform among aggregates present at the same flame location, but vary considerably with radius at a fixed distance from the burner. The maximum primary size in 0-g is found to be by 40% larger than in 1-g, under the same burner exit conditions. Estimates of the number concentration of primary particles and surface area of soot particulate phase per unit volume of the combustion gases are also made for selected in-flame locations.

  6. Effects of fuel type and equivalence ratios on the flickering of triple flames

    SciTech Connect (OSTI)

    Sahu, K.B.; Kundu, A.; Ganguly, R.; Datta, A. [Department of Power Engineering, Jadavpur University, Salt Lake Campus, Kolkata 700098 (India)

    2009-02-15T23:59:59.000Z

    An experimental study has been conducted in axisymmetric, co-flowing triple flames with different equivalence ratios of the inner and outer reactant streams (2<{phi}{sub in}<3 and 0{<=}{phi}{sub out}<0.7). Different fuel combinations, like propane/propane, propane/methane or methane/methane in the inner and outer streams respectively, have been used in the experiments. The structures of the triple flames have been compared for the different fuel combinations and equivalence ratios. The conditions under which triple flames exhibit oscillation have been identified. During the oscillation, the non-premixed flame and the outer lean premixed flame flicker strongly, while the inner rich premixed flame remains more or less stable. The flickering frequency has been evaluated through image processing and fast Fourier transform (FFT) of the average pixel intensity of the image frames. It is observed that, for all the fuel combinations, the frequency decreases with the increase in the outer equivalence ratio, while it is relatively invariant with the change in the inner equivalence ratio. However, an increase in the inner equivalence ratio affects the structure of the flame by increasing the heights of the inner premixed flame and non-premixed flame and also enlarges the yellow soot-laden zone at the tip of the inner flame. A scaling analysis of the oscillating flames has been performed based on the measured parameters, which show a variation of Strouhal number (St) with Richardson number (Ri) as St {proportional_to} Ri{sup 0.5}. The fuel type is found to have no influence on this correlation. (author)

  7. Phase control in the synthesis of yttrium oxide nano and micro-particles by flame spray pyrolysis

    E-Print Network [OSTI]

    Mukundan, Mallika

    2009-05-15T23:59:59.000Z

    The project synthesizes phase pure Yttria particles using flame spray pyrolysis, and to experimentally determines the effect of various process parameters like residence time, adiabatic flame temperature and precursor droplet size on the phase...

  8. Invited Contribution to Q 76: The Use of Risk Analysis to Support Dam Safety Decisions and Management

    E-Print Network [OSTI]

    Bowles, David S.

    Decisions and Management DRAFT FOR REVIEW ONLY Portfolio Risk Assessment: A Tool for Managing Dam SafetyICOLD 20th Congress Invited Contribution to Q 76: The Use of Risk Analysis to Support Dam Safety in the Context of the Owner's Business David S. Bowles Professor and Director, Institute for Dam Safety Risk

  9. RISK-BASED EVALUATION OF OPERATING RESTRICTIONS TO REDUCE THE RISK OF EARTHQUAKE-INDUCED DAM FAILURE

    E-Print Network [OSTI]

    Bowles, David S.

    and consequences of an Earthquake-induced dam failure. The potential for both a sudden overtopping failure-induced dam failure, and the estimated residual risk and degree of risk-based justification for the Existing into the relationship between pool elevation and dam failure risk, provided important inputs for the decision

  10. Received 8 Jul 2014 | Accepted 8 Aug 2014 | Published 19 Sep 2014 Kinetochores require oligomerization of Dam1

    E-Print Network [OSTI]

    Asbury, Chip

    -deficient Dam1 complex is unable to support stable bipolar alignment of sister chromatids, indicating failure oligomerization of Dam1 complex to maintain microtubule attachments against tension and promote biorientation Neil-cell imaging, we find that oligomerization of the Dam1 complex is required for its ability to form microtubule

  11. A DETAILED RESEARCH PLAN TO ASSESS BEHAVIOR OF ADULT SUMMER/FALL CHINOOK UPSTREAM OF WELLS DAM USING

    E-Print Network [OSTI]

    A DETAILED RESEARCH PLAN TO ASSESS BEHAVIOR OF ADULT SUMMER/FALL CHINOOK UPSTREAM OF WELLS DAM-8295 Final Draft April 19, 2004 #12;BioAnalysts, Inc Summer/Fall Chinook Research Plan Chief Joseph Dam Page........................................................................ 11 3.6.3 Chief Joseph Dam Powerhouse

  12. Design of dry dams at watershed scale : lessons learnt from sensitivity analyses using a simple but consistent rainfall-runoff

    E-Print Network [OSTI]

    Boyer, Edmond

    Design of dry dams at watershed scale : lessons learnt from sensitivity analyses using a simple Lyon, FRANCE Abstract We investigate the assessment of the overall efficiency of a set of dry dams of the best locations for a set of dams was previously studied using a simplistic rainfall-runoff model

  13. August 2002 / Vol. 52 No. 8 BioScience 659 Dams are structures designed by humans to capture

    E-Print Network [OSTI]

    Poff, N. LeRoy

    August 2002 / Vol. 52 No. 8 BioScience 659 Articles Dams are structures designed by humans to capture water and modify the magnitude and timing of its movement downstream. The damming of streams, dams have reduced flood hazard and allowed humans to settle and farm pro- ductive alluvial soils

  14. Experiments on upstream-migrating erosional narrowing and widening of an incisional channel caused by dam removal

    E-Print Network [OSTI]

    Paola, Chris

    by dam removal Alessandro Cantelli Department of Environmental Engineering, University of Genova, Italy on a laboratory investigation of the erosion of a deltaic front induced by the removal of a dam. We built a laboratory model of a dam, and observed both the sedimentation in the reservoir due to the downstream

  15. An adaptive time-space dual algorithm for shallow non-Newtonian power-law fluids: the horizontal dam break

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    dam break problem revisited P. Saramito a C. Smutek b B. Cordonnier b aLJK ­ CNRS et Universit´es de´eunion, France Abstract ­ The dam break problem shallow approximation for laminar flows of viscoplastic non equations for non-Newtonian fluids subject to the horizontal dam break problem. Keywords ­ viscoplastic

  16. Effects of Jackson Lake Dam on the Snake River and its floodplain, Grand Teton National Park, Wyoming, USA

    E-Print Network [OSTI]

    Marston, Richard A.

    Effects of Jackson Lake Dam on the Snake River and its floodplain, Grand Teton National Park In 1906, the Bureau of Reclamation created Jackson Lake Dam on the Snake River in what later became Grand Teton National Park. The geomorphic, hydrologic and vegetation adjustments downstream of the dam have

  17. THE INFLUENCE OF MAJOR DAMS ON HYDROLOGY THROUGH THE DRAINAGE NETWORK OF THE SACRAMENTO RIVER BASIN, CALIFORNIA

    E-Print Network [OSTI]

    Singer, Michael

    THE INFLUENCE OF MAJOR DAMS ON HYDROLOGY THROUGH THE DRAINAGE NETWORK OF THE SACRAMENTO RIVER BASIN downstream of major dams and confluences in the Sacramento River basin in California, USA. Streamflow data from 10 gauging stations downstream of major dams were divided into hydrologic series corresponding

  18. Dam and Hydroelectric Powerplant University of Hawai`i CEE 491University of Hawai`i CEE 491

    E-Print Network [OSTI]

    Prevedouros, Panos D.

    Karun 3 Dam and Hydroelectric Powerplant University of Hawai`i ­ CEE 491University of Hawai`i ­ CEE;Location #12;Description/Background Hydroelectric dam on Karun River Help with national energy needs #12;Social & Economic Benefits Flood Control Dam reservoirs help to control floods Mitigate high peak

  19. INFLUENCE OF ROCKY REACH DAM AND THE TEMPERATURE OF THE OKANOGAN RIVER ON THE UPSTREAM MIGRATION OF SOCKEYE

    E-Print Network [OSTI]

    INFLUENCE OF ROCKY REACH DAM AND THE TEMPERATURE OF THE OKANOGAN RIVER ON THE UPSTREAM MIGRATION Reach Dam, constructed on the Columbia River 7 miles above Wenatchee, Wash.· in 1957-61, has not appreciably increased the time required for adult sockeye salmon (Oncorhynchus nerka) to mi~rate to Zosel Dam

  20. Soot formation and temperature field structure in co-flow laminar methaneair diffusion flames

    E-Print Network [OSTI]

    Gülder, Ömer L.

    at higher pressures mean that the thermal diffusion from the hot regions of the flame towards the flame of the spread of unwanted fires. Soot radiation is the major heat load on combustor components causing mainte gas turbine combustors operate at elevated pressures, our understanding of the effects of pressure

  1. 45 (2008-5) Thermal Effect of Wall on Micro Premixed Flame in Quartz Channels

    E-Print Network [OSTI]

    Kasagi, Nobuhide

    E131 45 (2008-5) 225 Thermal Effect of Wall on Micro Premixed Flame in Quartz Channels * Yong flame propagation and quenching in three quartz combustors with chamber depth of 0.7 mm, 1.0 mm and 1 to meet the requirement. Hydrocarbon-fueled micro combustor is of great interest in portable power

  2. Flame transfer function saturation mechanisms in a swirl-stabilized combustor

    E-Print Network [OSTI]

    Lieuwen, Timothy C.

    oscillations using phase-locked, two-dimensional OH PLIF imaging. It focuses upon two repre- sentative An understanding of the amplitude dependence of the flame response to harmonic acoustic excitation is required during the phase of the cycle of peak instantaneous axial velocity. This causes the flame attachment

  3. Growth of diamond films using an enclosed methyl-acetylene and propadiene combustion flame

    E-Print Network [OSTI]

    Dandy, David

    1 Growth of diamond films using an enclosed methyl-acetylene and propadiene combustion flame K Abstract Diamond growth in low pressure combustion flames was studied using a safer, more economical and chemical kinetic time scales in the combustion reactor. 1 Present Address: 3M Corporation, Bldg. 60-1N-01

  4. Timewise morphology of turbulent diffusion flame by means of image processing

    SciTech Connect (OSTI)

    Torii, Shuichi; Yano, Toshiaki; Tsuchino, Fumihiro

    1999-07-01T23:59:59.000Z

    An experimental study is performed to investigate the dynamic behavior of jet diffusion flames from a vertical circular nozzle. A real-time image processing on slow-motion video recording using the high-speed video camera is employed to clarify the flame morphology. Emphasis is placed on the timewise variation of the flame length, H, the peripheral distance of the flame, L, and the projected area of the flame contour, S, based on the RGB values of the flame. Here, RGB implies the three primary colors, i.e., red, green and blue, respectively. Propane is used as fuel and a burner tube of 2.40 mm inside diameter is employed here. It is found from the study that (1) a real-time color image processing with the aid of a slow-motion video recording discriminates the flame shape and discloses the flame behavior with time, (2) H, L and S vary periodically with time, and (3) the time-averaged value of L{sup 2}/S and its turbulence intensity, which is defined here, are intensified with an increase in the Reynolds number.

  5. Simulation of Nitrogen Emissions in a Premixed Hydrogen Flame Stabilized on a Low Swirl Burner

    E-Print Network [OSTI]

    Bell, John B.

    Abstract There is considerable interest in developing fuel-flexible, low emissions turbines for power generation. One ap- proach is based on burning a variety of lean premixed fuels with relatively low flame concentration and a corresponding in- crease in local flame temperature just downstream. In turn, these regions

  6. A LEAN METHANE PREMIXED LAMINAR FLAME DOPED WITH COMPONENTS OF DIESEL FUEL

    E-Print Network [OSTI]

    Boyer, Edmond

    A LEAN METHANE PREMIXED LAMINAR FLAME DOPED WITH COMPONENTS OF DIESEL FUEL PART I: N-BUTYLBENZENE E better understand the chemistry involved during the combustion of components of diesel fuel flow rate analyses. Keywords: Premixed laminar flame, methane, n-butylbenzene, modelling, diesel fuel

  7. Combustion and Flame 153 (2008) 367383 www.elsevier.com/locate/combustflame

    E-Print Network [OSTI]

    Aggarwal, Suresh K.

    for outwardly propagating spherical flames burning a mixture of natural gas and hydrogen. © 2008 The Combustion enrichment on the propagation characteristics of CH4­air triple flames Alejandro M. Briones a , Suresh K 22 February 2008 Available online 7 April 2008 Abstract The effects of H2 enrichment

  8. Combustion and Flame 145 (2006) 765778 www.elsevier.com/locate/combustflame

    E-Print Network [OSTI]

    Gülder, Ömer L.

    2006-01-01T23:59:59.000Z

    and temperature field structure in laminar propane­air diffusion flames at elevated pressures Décio S. Bento and the structure of the temperature field was studied in coflow propane­air laminar diffusion flames over to within 30% and both methods exhibited similar trends in the spatial distribution of soot concentration

  9. The Cellular Burning Regime in Type Ia Supernova Explosions - I. Flame Propagation into Quiescent Fuel

    E-Print Network [OSTI]

    F. K. Roepke; W. Hillebrandt; J. C. Niemeyer

    2003-12-03T23:59:59.000Z

    We present a numerical investigation of the cellular burning regime in Type Ia supernova explosions. This regime holds at small scales (i.e. below the Gibson scale), which are unresolved in large-scale Type Ia supernova simulations. The fundamental effects that dominate the flame evolution here are the Landau-Darrieus instability and its nonlinear stabilization, leading to a stabilization of the flame in a cellular shape. The flame propagation into quiescent fuel is investigated addressing the dependence of the simulation results on the specific parameters of the numerical setup. Furthermore, we investigate the flame stability at a range of fuel densities. This is directly connected to the questions of active turbulent combustion (a mechanism of flame destabilization and subsequent self-turbulization) and a deflagration-to-detonation transition of the flame. In our simulations we find no substantial destabilization of the flame when propagating into quiescent fuels of densities down to ~10^7 g/cm^3, corroborating fundamental assumptions of large-scale SN Ia explosion models. For these models, however, we suggest an increased lower cutoff for the flame propagation velocity to take the cellular burning regime into account.

  10. Studies on non-premixed flame streets in a mesoscale channel

    E-Print Network [OSTI]

    Ju, Yiguang

    Studies on non-premixed flame streets in a mesoscale channel Bo Xu *, Yiguang Ju Department of channel width, wall temperature, and flow rate on the dynamics of non-premix flames in a mesoscale The Combustion Institute. Published by Elsevier Inc. All rights reserved. Keywords: Mesoscale combustion; Non

  11. Combustion and Flame 145 (2006) 324338 www.elsevier.com/locate/combustflame

    E-Print Network [OSTI]

    Gülder, �mer L.

    . Guo et al. / Combustion and Flame 145 (2006) 324­338 325 for ethylene, propane, and butane counterflowCombustion and Flame 145 (2006) 324­338 www.elsevier.com/locate/combustflame Numerical study into account. Radiation heat transfer from CO2, CO, H2O, and soot was calculated using the discrete- ordinates

  12. Simulations of The Dalles Dam Proposed Full Length Spillwall

    SciTech Connect (OSTI)

    Rakowski, Cynthia L.; Perkins, William A.; Richmond, Marshall C.; Serkowski, John A.

    2008-02-25T23:59:59.000Z

    This report presents results of a computational fluid dynamics (CFD) modeling study to evaluatethe impacts of a full-length spillwall at The Dalles Dam. The full-length spillwall is being designed and evaluated as a structural means to improve tailrace egress and thus survival of juvenile fish passing through the spillway. During the course of this study, a full-length spillwall at Bays 6/7 and 8/9 were considered. The U.S. Army Corps of Engineers (USACE) has proposed extending the spillwall constructed in the stilling basin between spillway Bays 6 and 7 about 590 ft farther downstream. It is believed that the extension of the spillwall will improve egress conditions for downstream juvenile salmonids by moving them more rapidly into the thalweg of the river hence reducing their exposure to predators. A numerical model was created, validated, and applied the The Dalles Dam tailrace. The models were designed to assess impacts to flow, tailrace egress, navigation, and adult salmon passage of a proposed spill wall extension. The more extensive model validation undertaken in this study greatly improved our confidence in the numerical model to represent the flow conditions in The Dalles tailrace. This study used these validated CFD models to simulate the potential impacts of a spillwall extension for The Dalles Dam tailrace for two locations. We determined the following: (1)The construction of an extended wall (between Bays 6/7) will not adversely impact entering or exiting the navigation lock. Impact should be less if a wall were constructed between Bays 8/9. (2)The construction of a wall between Bays 6/7 will increase the water surface elevation between the wall and the Washington shore. Although the increased water surface elevation would be beneficial to adult upstream migrants in that it decreases velocities on the approach to the adult ladder, the increased flow depth would enhance dissolved gas production, impacting potential operations of the project because of water quality. A wall between Bays 8/9 should have a lesser impact as the confined spill would be across more bays and the relative flow constriction less. (3) The 405 kcfs case was used for the rapid assessment of flow conditions and hydraulic mechanisms that might be responsible for the unexpected erosion at the end of the shelf downstream of Bay 7.

  13. ORNL Trusted Corridors Project: Watts Bar Dam Inland Waterway Project

    SciTech Connect (OSTI)

    Walker, Randy M [ORNL; Gross, Ian G [ORNL; Smith, Cyrus M [ORNL; Hill, David E [ORNL

    2011-11-01T23:59:59.000Z

    Radiation has existed everywhere in the environment since the Earth's formation - in rocks, soil, water, and plants. The mining and processing of naturally occurring radioactive materials for use in medicine, power generation, consumer products, and industry inevitably generate emissions and waste. Radiological measuring devices have been used by industry for years to measure for radiation in undesired locations or simply identify radioactive materials. Since the terrorist attacks on the United States on 9-11-01 these radiation measuring devices have proliferated in many places in our nation's commerce system. DOE, TVA, the Army Corps and ORNL collaborated to test the usefulness of these devices in our nation's waterway system on this project. The purpose of the Watts Bar Dam ORNL Trusted Corridors project was to investigate the security, safety and enforcement needs of local, state and federal government entities for state-of-the-art sensor monitoring in regards to illegal cargo including utilization of the existing infrastructure. TVA's inland waterways lock system is a recognized and accepted infrastructure by the commercial carrier industry. Safety Monitoring activities included tow boat operators, commercial barges and vessels, recreational watercraft and their cargo, identification of unsafe vessels and carriers, and, monitoring of domestic and foreign commercial vessels and cargo identification. Safety Enforcement activities included cargo safety, tracking, identification of hazardous materials, waterway safety regulations, and hazardous materials regulations. Homeland Security and Law Enforcement Applications included Radiological Dispersive Devices (RDD) identification, identification of unsafe or illicit transport of hazardous materials including chemicals and radiological materials, and screening for shipments of illicit drugs. In the Fall of 2005 the SensorNet funding for the project expired. After several unsuccessful attempts to find a Federal sponsor to continue with the project, the Watts Bar Dam Project was canceled and the Exploranium radiation monitors were removed from the doors of Watts Bar Dam in early 2006. The DHS Domestic Nuclear Detection Office decided to proceed with a Pilot building on the ORNL work performed at the TN and SC weigh stations in the highway sector of the Trusted Corridors project and eventually expanded it to other southern states under the name of Southeastern Corridor Pilot Project (SETCP). Many of the Phase I goals were achieved however real-world test data of private watercraft and barges was never obtained.

  14. A New Type of Steady and Stable, Laminar, Premixed Flame in Ultra-Lean, Hydrogen-Air Combustion

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    A New Type of Steady and Stable, Laminar, Premixed Flame in Ultra-Lean, Hydrogen-Air Combustion in the development of combustion science. Several aspects of these two-dimensional flame cells are identified for premixed combustion when the other types of idealized flames are inapplicable. 1 #12;Nomenclature fuel

  15. Modeling of the formation of short-chain acids in propane flames F. Battin-Leclerc , 1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Modeling of the formation of short-chain acids in propane flames F. Battin-Leclerc , 1 , A. Simulations of lean (equivalence ratios from 0.9 to 0.48) laminar premixed flames of propane stabilized in a combustion apparatus which can easily be modeled, a laminar premixed flame of propane at atmospheric pressure

  16. Sudden acceleration of flames in open channels driven by hydraulic resistance

    E-Print Network [OSTI]

    Yanez, J; Bykov, V

    2012-01-01T23:59:59.000Z

    Hydrogen-air deflagrations with venting at the end of obstructed tubes are studied experimentally and numerically. A shockless transition to the so-called chocked regime of the flame propagation is reported. Mixtures with 13% vol. of hydrogen were ignited from the open end of the tube at the interface between fuel and the ambient air. Three venting ratios were selected, closed, 40% and 100%. In all cases the flame initially propagates without acceleration at a velocity close to the laminar flame speed. The flame configuration excludes most of conventionally acknowledged phenomena of the DDT, namely, volumetric explosions, igniting shock and shock waves interactions. However, after an induction period, of the order of 1 sec, the flame accelerates more than 100 times, within a period of 3-30 ms, until the steady-state choked regime is established. The mechanism of such rapid acceleration is investigated both numerically and analytically. A one dimensional reduced description was suggested and analyzed to model ...

  17. Spectroscopic analysis of diesel combustion flame by means of streak camera

    SciTech Connect (OSTI)

    Nagase, K.; Funatsu, K.

    1988-01-01T23:59:59.000Z

    Band spectra in ultraviolet and visible ranges contain information on the state of combustion flame. Measurement of those spectra in diesel combustion flame, however, has been regarded as impossible because of the obstruction of bright flame and soot. The phenomena of diesel combustion, therefore, have not been analyzed clearly from the viewpoint of chemical reaction. The authors inserted an optical fiber into the diesel combustion chamber to detect the flame. The combustion flame was recorded by a special spectroscopic apparatus, named Streak camera, and the recorded image was subjected to spectroscopic analysis. The result of the experiments confirmed the existence of band spectra emitted from CH and OH radicals in the ultraviolet and visible ranges. The recorded data made clear the progress of chemical reactions and the formation of intermediate products during the diesel combustion process.

  18. Rock Island Dam Smolt Monitoring; 1996 Annual Report.

    SciTech Connect (OSTI)

    McDonald, Robert (Chelan County Public Utility District No. 1, Power Operations Department, Wenatchee, WA)

    1996-10-01T23:59:59.000Z

    Downstream migrating salmon and steelhead (Oncoryhnchus spp.) smolts were monitored at the Rock Island Dam bypass trap from April 1--August 31, 1996. This was the twelfth consecutive year that the bypass trap was monitored. Data collected included: (1) number of fish collected by species, (2) number of fin clipped and/or Passive Integrated Transponder (PIT) tagged fish caught by species, (3) total number of fish showing signs of gas bubble trauma (GBT), (4) percent of descaled fish, and (5) daily average river flow, powerhouse {number_sign}1 flow, powerhouse {number_sign}2 flow and daily average spill. These data were transmitted to the Fish Passage Center (FPC), which manages the Smolt Monitoring Program throughout the Columbia River Basin. The Smolt Monitoring Program is used to manage the water budget, releasing upstream reservoir water storage allocated to supplement river flows during the downstream migration of juvenile salmonids.

  19. Monitoring of Juvenile Yearling Chinook Salmon and Steelhead Survival and Passage at Bonneville Dam, Spring 2010

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Faber, Derrek M.; Weiland, Mark A.; Carlson, Thomas J.

    2012-09-01T23:59:59.000Z

    The purpose of this study was to estimate the survival for yearling Chinook salmon and steelhead smolts during spring 2010 in a portion of the Columbia River that includes Bonneville Dam. The study estimated smolt survival from a virtual release at Bonneville Dam to a survival array 81 km downstream of Bonneville Dam. We also estimated median forebay residence time, median tailrace egress time, and spill passage efficiency (SPE), as required in the Columbia Basin Fish Accords. A single release design was used to estimate survival from Bonneville Dam to a primary array located 81 km downstream of Bonneville. The approach did not include a reference tailrace release. Releases of acoustic-tagged smolts above John Day Dam to Hood River contributed to the formation of virtual releases at a Bonneville Dam forebay entrance array and at the face of the dam. A total of 3,880 yearling Chinook salmon and 3,885 steelhead smolts were tagged and released in the investigation. The Juvenile Salmon Acoustic Telemetry System (JSATS) tag model number ATS-156dB, weighing 0.438 g in air, was used in this investigation.

  20. Monitoring of Juvenile Yearling Chinook Salmon and Steelhead Survival and Passage at Bonneville Dam, Spring 2010

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Faber, Derrek M.; Weiland, Mark A.; Carlson, Thomas J.

    2011-02-01T23:59:59.000Z

    The purpose of this study was to estimate the survival for yearling Chinook salmon and steelhead smolts during spring 2010 in a portion of the Columbia River that includes Bonneville Dam. The study estimated smolt survival from a virtual release at Bonneville Dam to a survival array 81 km downstream of Bonneville Dam. We also estimated median forebay residence time, median tailrace egress time, and spill passage efficiency (SPE), as required in the Columbia Basin Fish Accords. A single release design was used to estimate survival from Bonneville Dam to a primary array located 81 km downstream of Bonneville. The approach did not include a reference tailrace release. Releases of acoustic-tagged smolts above John Day Dam to Hood River contributed to the formation of virtual releases at a Bonneville Dam forebay entrance array and at the face of the dam. A total of 3,880 yearling Chinook salmon and 3,885 steelhead smolts were tagged and released in the investigation. The Juvenile Salmon Acoustic Telemetry System (JSATS) tag model number ATS-156dB, weighing 0.438 g in air, was used in this investigation.

  1. Effects of thermal radiation heat transfer on flame acceleration and transition to detonation in dust cloud flames: Origins of dust explosion

    E-Print Network [OSTI]

    Ivanov, Michael A Liberman M F

    2015-01-01T23:59:59.000Z

    We examines regimes of the hydrogen flames propagation and ignition of mixtures heated by the radiation emitted from the flame. The gaseous phase is assumed to be transparent for radiation, while the suspended particles of the dust cloud ahead of the flame absorb and reemit the radiation. The radiant heat absorbed by the particles is then lost by conduction to the surrounding unreacted gaseous phase so that the gas phase temperature lags that of the particles. The direct numerical simulations solve the full system of two phase gas dynamic time-dependent equations with a detailed chemical kinetics for a plane flames propagating through a dust cloud. Depending on the spatial distribution of the dispersed particles and on the value of radiation absorption length the consequence of the radiative preheating of the unreacted mixture can be either the increase of the flame velocity for uniformly dispersed particles or ignition deflagration or detonation ahead of the flame via the Zel'dovich gradient mechanism in the...

  2. Monitoring of Subyearling Chinook Salmon Survival and Passage at Bonneville Dam, Summer 2010

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Carlson, Thomas J.

    2012-09-01T23:59:59.000Z

    The purpose of this study was to estimate dam passage and route specific survival rates for subyearling Chinook salmon smolts to a primary survival-detection array located 81 km downstream of the dam, evaluate a BGS located in the B2 forebay, and evaluate effects of two spill treatments. The 2010 study also provided estimates of forebay residence time, tailrace egress time, spill passage efficiency (SPE), and spill + B2 Corner Collector (B2CC) efficiency, as required in the Columbia Basin Fish Accords. In addition, the study estimated forebay passage survival and survival of fish traveling from the forebay entrance array, through the dam and downstream through 81 km of tailwater.

  3. Monitoring of Subyearling Chinook Salmon Survival and Passage at Bonneville Dam, Summer 2010

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Carlson, Thomas J.

    2011-02-01T23:59:59.000Z

    The purpose of this study was to estimate dam passage and route specific survival rates for subyearling Chinook salmon smolts to a primary survival-detection array located 81 km downstream of the dam, evaluate a BGS located in the B2 forebay, and evaluate effects of two spill treatments. The 2010 study also provided estimates of forebay residence time, tailrace egress time, spill passage efficiency (SPE), and spill + B2 Corner Collector (B2CC) efficiency, as required in the Columbia Basin Fish Accords. In addition, the study estimated forebay passage survival and survival of fish traveling from the forebay entrance array, through the dam and downstream through 81 km of tailwater.

  4. Pocket formation and the flame surface density equation

    SciTech Connect (OSTI)

    Kollman, W. [Univ. of California, Davis, CA (United States); Chen, J.H. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility

    1998-03-01T23:59:59.000Z

    The occurrence and properties of singularities in the equation for the surface density function {sigma} {triple_bond}{vert_bar}{del}{Phi}{vert_bar} are analyzed analytically and numerically using data from two dimensional direct numerical simulation (DNS) of pocket formation in a premixed methane-air flame. The various stages and the relevant time scales associated with pocket formation were determined in a previous study. It was found that isolated pockets form if and only if a nondegenerate critical point of a saddle point type appears. The appearance of a singularity in the isoline representing the flame front may have implications to modeling of the terms in the surface density function (sdf) approach during such transient events as pocket formation. The sink and source terms in sdf are evaluated in the neighborhood of a critical point using DNS data during pocket formation, and an analytic representation of a scalar in the vicinity of the critical point which allows for the computation of all kinematic properties. The analytic and computational results show that the normal restoration and dissipation terms in the sdf become singular at the critical point when the pocket emerges. Furthermore, the analytic results show that the singularities exactly cancel, and therefore, the main conclusion is that it is unnecessary to model the singular behavior of these terms at critical points. However, closure of their sum is recommended.

  5. Understanding and predicting soot generation in turbulent non-premixed jet flames.

    SciTech Connect (OSTI)

    Wang, Hai (University of Southern California, Los Angeles, CA); Kook, Sanghoon; Doom, Jeffrey; Oefelein, Joseph Charles; Zhang, Jiayao; Shaddix, Christopher R.; Schefer, Robert W.; Pickett, Lyle M.

    2010-10-01T23:59:59.000Z

    This report documents the results of a project funded by DoD's Strategic Environmental Research and Development Program (SERDP) on the science behind development of predictive models for soot emission from gas turbine engines. Measurements of soot formation were performed in laminar flat premixed flames and turbulent non-premixed jet flames at 1 atm pressure and in turbulent liquid spray flames under representative conditions for takeoff in a gas turbine engine. The laminar flames and open jet flames used both ethylene and a prevaporized JP-8 surrogate fuel composed of n-dodecane and m-xylene. The pressurized turbulent jet flame measurements used the JP-8 surrogate fuel and compared its combustion and sooting characteristics to a world-average JP-8 fuel sample. The pressurized jet flame measurements demonstrated that the surrogate was representative of JP-8, with a somewhat higher tendency to soot formation. The premixed flame measurements revealed that flame temperature has a strong impact on the rate of soot nucleation and particle coagulation, but little sensitivity in the overall trends was found with different fuels. An extensive array of non-intrusive optical and laser-based measurements was performed in turbulent non-premixed jet flames established on specially designed piloted burners. Soot concentration data was collected throughout the flames, together with instantaneous images showing the relationship between soot and the OH radical and soot and PAH. A detailed chemical kinetic mechanism for ethylene combustion, including fuel-rich chemistry and benzene formation steps, was compiled, validated, and reduced. The reduced ethylene mechanism was incorporated into a high-fidelity LES code, together with a moment-based soot model and models for thermal radiation, to evaluate the ability of the chemistry and soot models to predict soot formation in the jet diffusion flame. The LES results highlight the importance of including an optically-thick radiation model to accurately predict gas temperatures and thus soot formation rates. When including such a radiation model, the LES model predicts mean soot concentrations within 30% in the ethylene jet flame.

  6. Monitoring and Evaluation of Yearling Fall Chinook Salmon Released from Acclimation Facilities Upstream of Lower Granite Dam; 1998 Annual Report.

    SciTech Connect (OSTI)

    Rocklage, Stephen J. (Nez Perce Tribe, Department of Fisheries Resource Management, Lapwai, ID)

    2004-01-01T23:59:59.000Z

    The Nez Perce Tribe, in cooperation with the U.S. Fish and Wildlife Service and Washington Department of Fish and Wildlife, conducted monitoring and evaluation studies on Lyons Ferry Hatchery (Snake River stock) yearling fall chinook salmon that were acclimated and released at three Fall Chinook Acclimation Project sites upstream of Lower Granite Dam along with yearlings released on-station from Lyons Ferry Hatchery in 1998. The three fall chinook acclimation facilities are operated by the Nez Perce Tribe and located at Pittsburg Landing and Captain John Rapids on the Snake River and at Big Canyon Creek on the Clearwater River. Yearlings at the Big Canyon facility consisted of two size classes that are referred to in this report as 9.5 fish per pound (fpp) and 30 fpp. The Big Canyon 9.5 fpp were comparable to the yearlings at Pittsburg Landing, Captain John Rapids and Lyons Ferry Hatchery. A total of 9,942 yearlings were PIT tagged and released at Pittsburg Landing. PIT tagged yearlings had a mean fork length of 159.9 mm and mean condition factor of 1.19. Of the 9,942 PIT tagged fish released, a total of 6,836 unique tags were detected at mainstem Snake and Columbia River dams (Lower Granite, Little Goose, Lower Monumental and McNary). A total of 4,926 9.5 fpp and 2,532 30 fpp yearlings were PIT tagged and released at Big Canyon. PIT tagged 9.5 fpp yearlings had a mean fork length of 156.9 mm and mean condition factor of 1.13. PIT tagged 30 fpp yearlings had a mean fork length of 113.1 mm and mean condition factor of 1.18. Of the 4,926 PIT tagged 9.5 fpp yearlings released, a total of 3,042 unique tags were detected at mainstem Snake and Columbia River dams. Of the 2,532 PIT tagged 30 fpp yearlings released, a total of 1,130 unique tags were detected at mainstem Snake and Columbia River dams. A total of 1,253 yearlings were PIT tagged and released at Captain John Rapids. PIT tagged yearlings had a mean fork length of 147.5 mm and mean condition factor of 1.09. Of the 1,253 PIT tagged fish released, a total of 719 unique tags were detected at mainstem Snake and Columbia River dams. A total of 2,420 yearlings were PIT tagged and released at Lyons Ferry Hatchery. PIT tagged yearlings had a mean fork length of 159.0 mm and mean condition factor of 1.10. Of the 2,420 PIT tagged fish released, a total of 979 unique tags were detected at mainstem Snake and Columbia River dams (Lower Monumental and McNary). Median travel times, based on all detections, of PIT tagged fish released from Pittsburg Landing were 10.5 days to Lower Granite Dam, 21.7 days to McNary Dam and 29.8 days to Bonneville Dam. Median migration rates were 16.4 rkm/d to Lower Granite Dam, 18.3 rkm/d to McNary Dam and 18.9 rkm/d to Bonneville Dam. The median arrival dates were April 25 at Lower Granite Dam, May 6 at McNary Dam and May 14 at Bonneville Dam. The 90% passage dates were May 5 at Lower Granite Dam, May 20 at McNary Dam and May 25 at Bonneville Dam. Median travel times, based on all detections, of PIT tagged 9.5 fpp yearlings released from Big Canyon were 13.3 days to Lower Granite Dam, 26.0 days to McNary Dam and 30.8 days to Bonneville Dam. Median migration rates were 13.0 rkm/d to Lower Granite Dam, 15.3 rkm/d to McNary Dam and 18.3 rkm/d to Bonneville Dam. The median arrival dates were April 27 at Lower Granite Dam, May 11 at McNary Dam and May 15 at Bonneville Dam. The 90% passage dates were May 9 at Lower Granite Dam, May 24 at McNary Dam and May 25 at Bonneville Dam. Median travel times, based on all detections, of PIT tagged 30 fpp yearlings released from Big Canyon were 20.8 days to Lower Granite Dam, 37.6 days to McNary Dam and 43.5 days to Bonneville Dam. Median migration rates were 8.3 rkm/d to Lower Granite Dam, 10.6 rkm/d to McNary Dam and 12.9 rkm/d to Bonneville Dam. The median arrival dates were May 5 at Lower Granite Dam, May 23 at McNary Dam and May 28 at Bonneville Dam. The 90% passage dates were May 22 at Lower Granite Dam, May 31 at McNary Dam and June 5 at Bonneville Dam. Median arrival dates, based on all detections, of PIT tagge

  7. The Cellular Burning Regime in Type Ia Supernova Explosions - II. Flame Propagation into Vortical Fuel

    E-Print Network [OSTI]

    F. K. Roepke; W. Hillebrandt; J. C. Niemeyer

    2003-12-08T23:59:59.000Z

    We investigate the interaction of thermonuclear flames in Type Ia supernova explosions with vortical flows by means of numerical simulations. In our study, we focus on small scales, where the flame propagation is no longer dominated by the turbulent cascade originating from large-scale effects. Here, the flame propagation proceeds in the cellular burning regime, resulting from a balance between the Landau-Darrieus instability and its nonlinear stabilization. The interaction of a cellularly stabilized flame front with a vortical fuel flow is explored applying a variety of fuel densities and strengths of the velocity fluctuations. We find that the vortical flow can break up the cellular flame structure if it is sufficiently strong. In this case the flame structure adapts to the imprinted flow field. The transition from the cellularly stabilized front to the flame structure dominated by vortices of the flow proceeds in a smooth way. The implications of the results of our simulations for Type Ia Supernova explosion models are discussed.

  8. Numerical study of the direct pressure effect of acoustic waves in planar premixed flames

    SciTech Connect (OSTI)

    Schmidt, H. [BTU Cottbus, Siemens-Halske-Ring 14, D-03046 Cottbus (Germany); Jimenez, C. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Avenida Complutense, 22, 28040 Madrid (Spain)

    2010-08-15T23:59:59.000Z

    Recently the unsteady response of 1-D premixed flames to acoustic pressure waves for the range of frequencies below and above the inverse of the flame transit time was investigated experimentally using OH chemiluminescence Wangher (2008). They compared the frequency dependence of the measured response to the prediction of an analytical model proposed by Clavin et al. (1990), derived from the standard flame model (one-step Arrhenius kinetics) and to a similar model proposed by McIntosh (1991). Discrepancies between the experimental results and the model led to the conclusion that the standard model does not provide an adequate description of the unsteady response of real flames and that it is necessary to investigate more realistic chemical models. Here we follow exactly this suggestion and perform numerical studies of the response of lean methane flames using different reaction mechanisms. We find that the global flame response obtained with both detailed chemistry (GRI3.0) and a reduced multi-step model by Peters (1996) lies slightly above the predictions of the analytical model, but is close to experimental results. We additionally used an irreversible one-step Arrhenius reaction model and show the effect of the pressure dependence of the global reaction rate in the flame response. Our results suggest first that the current models have to be extended to capture the amplitude and phase results of the detailed mechanisms, and second that the correlation between the heat release and the measured OH* chemiluminescence should be studied deeper. (author)

  9. Stabilization of turbulent lifted jet flames assisted by pulsed high voltage discharge

    SciTech Connect (OSTI)

    Criner, K.; Cessou, A.; Louiche, J.; Vervisch, P. [CORIA UMR 6614 CNRS-Universite et INSA de Rouen, University of Rouen, 76801 Saint Etienne du Rouvray (France)

    2006-01-01T23:59:59.000Z

    To reduce fuel consumption or the pollutant emissions of combustion (furnaces, aircraft engines, turbo-reactors, etc.), attempts are made to obtain lean mixture combustion regimes. These lead to poor stability of the flame. Thus, it is particularly interesting to find new systems providing more flexibility in aiding flame stabilization than the usual processes (bluff-body, stabilizer, quarl, swirl, etc.). The objective is to enlarge the stability domain of flames while offering flexibility at a low energy cost. Evidence is presented that the stabilization of a turbulent partially premixed flame of more than 10 kW can be enhanced by pulsed high-voltage discharges with power consumption less than 0.1% of the power of the flame. The originality of this work is to demonstrate that very effective stabilization of turbulent flames is obtained when high-voltage pulses with very short rise times are used (a decrease by 300% in terms of liftoff height for a given exit jet velocity can be reached) and to provide measurements of minimum liftoff height obtained with discharge over a large range of the stability domain of the lifted jet flame.

  10. Sensor and model integration for the rapid prediction of concurrent flow flame spread 

    E-Print Network [OSTI]

    Cowlard, Adam

    Fire Safety Engineering is required at every stage in the life cycle of modern-day buildings. Fire safety design, detection and suppression, and emergency response are all vital components of Structural Fire Safety but are usually perceived...Issues of accuracy aside, these models demand heavy resources and computational time periods that are far greater than the time associated with the processes being simulated. To be of use to emergency responders, the output would need to be produced faster than the event itself with lead time to enable planning of an intervention strategy. Therefore in isolation, model output is not robust or fast enough to be implemented in an emergency response scenario. The concept of super-real time predictions steered by measurements is studied in the simple yet meaningful scenario of concurrent flow flame spread. Experiments have been conducted with PMMA slabs to feed sensor data into a simple analytical model. Numerous sensing techniques have been adapted to feed a simple algebraic expression from the literature linking flame spread, flame characteristics and pyrolysis evolution in order to model upward flame spread. The measurements are continuously fed to the computations so that projections of the flame spread velocity and flame characteristics can be established at each instant in time, ahead of the real flame. It was observed that as the input parameters in the analytical models were optimised to the scenario, rapid convergence between the evolving experiment and the predictions was attained....

  11. Soot volume fraction and temperature measurements in laminar nonpremixed flames using thermocouples

    SciTech Connect (OSTI)

    Mcenally, C.S.; Koeylue, U.O.; Pfefferle, L.D.; Rosner, D.E. [Yale Univ., New Haven, CT (United States)] [Yale Univ., New Haven, CT (United States)

    1997-06-01T23:59:59.000Z

    Thermocouple particle densitometry (TPD), a new method for measuring absolute soot volume fraction in flames which was suggested by Eisner and Rosner, has been successfully implemented in several laminar nonpremixed flames. This diagnostic relies on measuring the junction temperature history of a thermocouple rapidly inserted into a soot-containing flame region, then optimizing the fit between this history and one calculated from the principles of thermophoretic mass transfer. The TPD method is very simple to implement experimentally, yields spatially resolved volume fractions directly, can easily measure small volume fractions, and does not depend on the prevailing soot particle size, morphology, or optical characteristics. In a series of methane and ethylene counterflow flames whose soot volume fractions varied by more than an order of magnitude, the TPD results agreed to within experimental error with the authors own laser extinction measurements. In axisymmetric methane and ethylene co-flowing flames, the shape of TPD profiles agreed well with published laser extinction measurements, but the TPD concentrations were significantly larger in the early regions of the ethylene flame and throughout the methane flame; these discrepancies are probably attributable to visible light-transparent particles that are detectable with TPD but not with laser extinction. The TPD method is not applicable to the upper regions of these co-flowing flames since OH concentrations there suffice to rapidly oxidize any soot particles that deposit. Gas temperatures were obtained simultaneously with volume fraction by averaging the junction temperature history shortly after insertion. The error in these temperatures due to soot deposition-imposed changes in the junction diameter and emissivity were assessed and found to be moderate, e.g., less than 60 K near the centerline of the ethylene coflowing flame where the volume fraction was 6 ppm and the gas temperature was 1,550 K.

  12. Monitoring of Juvenile Subyearling Chinook Salmon Survival and Passage at John Day Dam, Summer 2010

    SciTech Connect (OSTI)

    Weiland, Mark A.; Ploskey, Gene R.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Skalski, J. R.; Townsend, Richard L.

    2012-11-15T23:59:59.000Z

    The purpose of this study was to evaluate dam passage survival of subyearling Chinook salmon (Oncorhynchus tshawytscha; CH0) at John Day Dam (JDA) during summer 2010. This study was conducted by researchers from the Pacific Northwest National Laboratory (PNNL) in collaboration with the Pacific States Marine Fisheries Commission (PSMFC) and the University of Washington (UW). The study was designed to estimate the effects of 30% and 40% spill treatment levels on single release survival rates of CH0 passing through two reaches: (1) the dam, and 40 km of tailwater, (2) the forebay, dam, and 40 km of tailwater. The study also estimated additional passage performance measures which are stipulated in the Columbia Basin Fish Accords.

  13. Post-project appraisal of lower Ritchie Creek dam removal, Napa County

    E-Print Network [OSTI]

    Daniels, Jubilee; Pagano, Laura

    2004-01-01T23:59:59.000Z

    Appraisal of Lower Ritchie Creek Dam Removal, Napa CountyApril 2004 Abstract Ritchie Creek drains 2.6 square milesdam was built in 1912 on Ritchie Creek to facilitate water

  14. Economic Implications of New Crops, Row Damming and Land Clearing in the Texas Winter Garden

    E-Print Network [OSTI]

    Muncrief, G.E.; Lacewell, R. D.; Cornforth, G. C.; Pena, J. G.

    TR- 123 1983 Economic Implications of New Crops, Row Damming and Land Clearing in the Texas Winter Garden G.E. Muncrief R.D. Lacewell G.C. Cornforth J.G. Pena Texas Water Resources Institute...

  15. The costs of breaching the four lower Snake River dams - BPA...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    shing groups recently released their analysis of breaching the four lower Snake River dams. The authors of "Revenue Stream" did not seek input from BPA or other federal agencies...

  16. Appearance, temperature, and NO{sub x} emission of two inverse diffusion flames with different port design

    SciTech Connect (OSTI)

    Sze, L.K.; Cheung, C.S.; Leung, C.W. [Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong (China)

    2006-01-01T23:59:59.000Z

    Experiments were carried out to investigate the appearance, temperature distribution, and NO{sub x} emission index of two inverse diffusion flames, one with circumferentially arranged ports (CAPs) and the other with co-axial (CoA) jets, both burning LPG with 70% butane and 30% propane. Flame appearances were investigated first with a fixed fueling rate at different airflow rates equivalent to air jet Reynolds numbers (Re) of 1000 to 4500; and then at a fixed airflow rate with different fueling rates equivalent to overall equivalence ratios (F) of 1.0 to 2.0. The CAP flame is found to consist of two zones: a lower entrainment zone and an upper mixing and combustion zone. The CoA flame in most cases is similar to a diffusion flame. The two-zone structure can be observed only at Re larger than 2500. The temperature distributions of the flames are similar at overall equivalence ratios of 1.0 and 1.2 for Re=2500, except that the corresponding CoA flame is longer. The flame temperature is higher in the CAP flame than the CoA flame at higher overall equivalence ratios. A measurement of centerline oxygen concentrations shows that the oxygen concentration reaches a minimum value at a flame height of 50 mm in the CAP flame but decreases more gradually in the CoA flame. It can be concluded that there is more intense air-fuel mixing in a CAP flame than the CoA flame. Investigation of the emission index of NO{sub x} (EINO{sub x}) for both flames at Re=2500 and overall equivalence ratios of 1.0 to 6.0 reveals that the EINO{sub x} curve of each flame is bell-shaped, with a maximum value of 3.2 g/kg at F=1.2 for the CAP flame and 3 g/kg at F=2.2 for the CoA flame.

  17. EIS-0480: Long-Term Experimental and Management Plan for the Operation of Glen Canyon Dam

    Broader source: Energy.gov [DOE]

    Two agencies of the Department of the Interior, Bureau of Reclamation and National Park Service, are jointly preparing a Long-Term Experimental and Management Plan for the Glen Canyon Dam and an EIS for adoption of the Plan. The Glen Canyon Dam, on the Colorado River in northern, Arizona, generates hydroelectric power that is marketed by DOE's Western Area Power Administration, a cooperating agency.

  18. Factors affecting calf and dam weights and their effects on breeding programs

    E-Print Network [OSTI]

    Maddox, Lawrence Allen

    1964-01-01T23:59:59.000Z

    FACTORS AFFECTING CALF AND DAM WEIGHTS AND THEIR EFFECTS ON BREEDING PROGRAMS A Thesis By LAMRENCE ALLEN MADDOX, JR. Submitted to the Graduate College of the Texas A&M University in partial fulf illment of the requirements for the degree... of MASTER OF SCIENCE May, 1964 Major Subject: Animal Breeding FACTORS AFFECTING CALF AND DAM WEIGHTS AND THEIR EFFECTS ON BREEDING PROGRAMS A Thesis By IAWRENCE ALLEN MADDOX, JR Approved as to style and content by: (Chairman of Commit ee) (Head...

  19. Optimization of Hydroacoustic Equipment Deployments at Lookout Point and Cougar Dams, Willamette Valley Project, 2010

    SciTech Connect (OSTI)

    Johnson, Gary E.; Khan, Fenton; Ploskey, Gene R.; Hughes, James S.; Fischer, Eric S.

    2010-08-18T23:59:59.000Z

    The goal of the study was to optimize performance of the fixed-location hydroacoustic systems at Lookout Point Dam (LOP) and the acoustic imaging system at Cougar Dam (CGR) by determining deployment and data acquisition methods that minimized structural, electrical, and acoustic interference. The general approach was a multi-step process from mount design to final system configuration. The optimization effort resulted in successful deployments of hydroacoustic equipment at LOP and CGR.

  20. Non-powered Dams: An untapped source of renewable electricity in the USA

    SciTech Connect (OSTI)

    Hadjerioua, Boualem [ORNL; Kao, Shih-Chieh [ORNL; Wei, Yaxing [ORNL; Battey, Hoyt [Department of Energy; Smith, Brennan T [ORNL

    2012-01-01T23:59:59.000Z

    Hydropower has been a source of clean, renewable electricity in the USA for more than 100 years. Today, approximately 2500 US dams provide 78 GW of conventional and 22 GW of pumped-storage hydropower. In contrast, another approximately 80 000 dams in the USA do not include hydraulic turbine equipment and provide non-energy related services, such as flood control, water supply, navigation, and recreation.

  1. Temperature measurement of axisymmetric flames under the influence of magnetic field using Talbot interferometry

    SciTech Connect (OSTI)

    Agarwal, Shilpi, E-mail: sipi.agarwal@gmail.com, E-mail: manojklakra@gmail.com, E-mail: cshakher@iddc.iitd.ac.in; Kumar, Manoj, E-mail: sipi.agarwal@gmail.com, E-mail: manojklakra@gmail.com, E-mail: cshakher@iddc.iitd.ac.in; Shakher, Chandra, E-mail: sipi.agarwal@gmail.com, E-mail: manojklakra@gmail.com, E-mail: cshakher@iddc.iitd.ac.in [Instrument Design Development Centre, Indian Institute of Technology Delhi, HauzKhas, New Delhi - 110016 (India)

    2014-10-15T23:59:59.000Z

    Combustion process control is related with ecological improvement and the problem of energy efficiency; hence it has a wide interest at both economical and scientific levels. Application of a magnetic field is one of the most promising methods of combustion control. The presence of magnetic field induces the changes in flame behavior. The effect of uniform magnetic field developed by permanent magnet is studied by Talbot interferometry using circular gratings. Experimental results show a small decrease in flame temperature and increase in flame dimensions.

  2. Simulations of flame acceleration and deflagration-to-detonation transitions in methane-air systems

    SciTech Connect (OSTI)

    Kessler, D.A.; Gamezo, V.N.; Oran, E.S. [Laboratory for Computational Physics and Fluid Dynamics, Naval Research Laboratory, Washington, DC (United States)

    2010-11-15T23:59:59.000Z

    Flame acceleration and deflagration-to-detonation transitions (DDT) in large obstructed channels filled with a stoichiometric methane-air mixture are simulated using a single-step reaction mechanism. The reaction parameters are calibrated using known velocities and length scales of laminar flames and detonations. Calculations of the flame dynamics and DDT in channels with obstacles are compared to previously reported experimental data. The results obtained using the simple reaction model qualitatively, and in many cases, quantitatively match the experiments and are found to be largely insensitive to small variations in model parameters. (author)

  3. Hydropower and the environment: A case study at Glen Canyon Dam

    SciTech Connect (OSTI)

    Wegner, D.L. [Denver Technical Service Center, Flagstaff, AZ (United States)

    1995-12-31T23:59:59.000Z

    The management of hydroelectric resources in the Colorado River requires a balancing of hydrologic, social, natural and cultural resources. The resulting management often has to deal with inherently conflicting objectives, short and long-term goals, time frames and operational flexibility. Glen Canyon Dam, AZ, on the Colorado River, controls the release of water into the Grand Canyon. The dam has been under intense public scrutiny since it was completed in 1963. An Environmental Impact Statement evaluating the future operations and options for Glen Canyon Dam was initiated by the Department of the Interior in 1989 and completed in 1995. An Adaptive Management approach to future operational management has been developed as part of the Glen Canyon Dam Environmental Impact Statement process. Future operations at Glen Canyon Dam will take into consideration the need to balance water movement and hydroelectricity development with natural, recreation, Native American and cultural needs. Future management of rivers requires acknowledgement of the dynamic nature of ecosystems and the need to link scientific information into the decision-making process. Lessons learned and programs developed at Glen Canyon Dam may be applied to other river systems.

  4. Pdf modeling of turbulent nonpremixed methane jet flames

    SciTech Connect (OSTI)

    Chen, J.Y.; Kollmann, W.; Dibble, R.W. (Sandia National Labs., Livermore, CA (USA). Combustion Research Faclity)

    1989-01-01T23:59:59.000Z

    An expanded model of turbulent nonpremixed combustion is presented. In the model, the scalar mixing and reactions are described by a probability density function (pdf) submodel capable of handling five scalars, while the turbulent velocity field is described by a second-order moment closure. Two plausible chemical reaction models are considered: a five-scalar, four-step, reduced reaction mechanism, and a four-scalar constrained equilibrium model. Detailed comparisons of model predictions with laser Raman experimental dat provide a valuable evaluation of the model's ability in predicting nonequilibrium chemistry in turbulent nonpremixed flames. Overall, the model fails to predict greater departure from chemical equilibrium as mixing rates are increased. Interestingly, this failure is not due to the chemical model, both of which perform satisfactorily. Instead, the failure to predict greater departure from chemical equilibrium is a subtle artifact of the current Monte Carlo simulation of turbulent mixing and chemical reaction.

  5. The ignition of thermonuclear flames in Type Ia supernovae

    E-Print Network [OSTI]

    L. Iapichino; M. Brüggen; W. Hillebrandt; J. C. Niemeyer

    2005-12-12T23:59:59.000Z

    In the framework of the Chandrasekhar-mass deflagration model for Type Ia supernovae (SNe Ia), a persisting free parameter is the initial morphology of the flame front, which is linked to the ignition process in the progenitor white dwarf. Previous analytical models indicate that the thermal runaway is driven by temperature perturbations (''bubbles'') that develop in the white dwarf's convective core. In order to probe the conditions at ignition (diameters, temperatures and evolutionary timescales), we have performed hydrodynamical 2D simulations of buoyant bubbles in white dwarf interiors. Our results show that fragmentation occurring during the bubble rise affects the outcome of the bubble evolution. Possible implications for the ignition process of SNe Ia are discussed.

  6. The ignition of thermonuclear flames in Type Ia supernovae

    E-Print Network [OSTI]

    Iapichino, L; Hillebrandt, W; Niemeyer, J C

    2005-01-01T23:59:59.000Z

    In the framework of the Chandrasekhar-mass deflagration model for Type Ia supernovae (SNe Ia), a persisting free parameter is the initial morphology of the flame front, which is linked to the ignition process in the progenitor white dwarf. Previous analytical models indicate that the thermal runaway is driven by temperature perturbations (''bubbles'') that develop in the white dwarf's convective core. In order to probe the conditions at ignition (diameters, temperatures and evolutionary timescales), we have performed hydrodynamical 2D simulations of buoyant bubbles in white dwarf interiors. Our results show that fragmentation occurring during the bubble rise affects the outcome of the bubble evolution. Possible implications for the ignition process of SNe Ia are discussed.

  7. FLAME-SAMPLING PHOTOIONIZATION MASS SPECTROSCOPY - FINAL TECHNICAL REPORT

    SciTech Connect (OSTI)

    Hansen, Nils

    2013-02-12T23:59:59.000Z

    Research focused on detailed studies of the complex combustion chemistry of oxygenated, bio-derived fuels. In particular, studies were done of the flame chemistry of simple methyl and ethyl esters chosen as surrogates for the long-chain esters that are primary constituents of biodiesel fuels. The principal goals of these studies were: (1) show how fuel-specific structural differences including degree of unsaturation, linear vs. branched chain structures, and methoxy vs. ethoxy functions affect fueldestruction pathways, (2) understand the chemistry leading to potential increases in the emissions of hazardous air pollutants including aldehydes and ketones inherent in the use of biodiesel fuels, and (3) define the key chemical reaction mechanisms responsible for observed reductions in polycyclic aromatic hydrocarbons and particulate matter when oxygenated fuels are used as replacements for conventional fuels.

  8. Stochastic algorithms for the analysis of numerical flame simulations

    SciTech Connect (OSTI)

    Bell, John B.; Day, Marcus S.; Grcar, Joseph F.; Lijewski, Michael J.

    2004-04-26T23:59:59.000Z

    Recent progress in simulation methodologies and high-performance parallel computers have made it is possible to perform detailed simulations of multidimensional reacting flow phenomena using comprehensive kinetics mechanisms. As simulations become larger and more complex, it becomes increasingly difficult to extract useful information from the numerical solution, particularly regarding the interactions of the chemical reaction and diffusion processes. In this paper we present a new diagnostic tool for analysis of numerical simulations of reacting flow. Our approach is based on recasting an Eulerian flow solution in a Lagrangian frame. Unlike a conventional Lagrangian view point that follows the evolution of a volume of the fluid, we instead follow specific chemical elements, e.g., carbon, nitrogen, etc., as they move through the system . From this perspective an ''atom'' is part of some molecule of a species that is transported through the domain by advection and diffusion. Reactions cause the atom to shift from one chemical host species to another and the subsequent transport of the atom is given by the movement of the new species. We represent these processes using a stochastic particle formulation that treats advection deterministically and models diffusion and chemistry as stochastic processes. In this paper, we discuss the numerical issues in detail and demonstrate that an ensemble of stochastic trajectories can accurately capture key features of the continuum solution. The capabilities of this diagnostic are then demonstrated by applications to study the modulation of carbon chemistry during a vortex-flame interaction, and the role of cyano chemistry in rm NO{sub x} production for a steady diffusion flame.

  9. Operation of the Lower Granite Dam Adult Trap, 2008.

    SciTech Connect (OSTI)

    Harmon, Jerrel R.

    2009-01-01T23:59:59.000Z

    During 2008 we operated the adult salmonid trap at Lower Granite Dam from 7 March through 25 November, except during a short summer period when water temperatures were too high to safely handle fish. We collected and handled a total of 20,463 steelhead Oncorhynchus mykiss and radio-tagged 34 of the hatchery steelhead. We took scale samples from 3,724 spring/summer Chinook salmon O. tshawytscha for age and genetic analysis. We collected and handled a total of 8,254 fall Chinook salmon. Of those fish, 2,520 adults and 942 jacks were transported to Lyons Ferry Hatchery on the Snake River in Washington. In addition, 961 adults and 107 jacks were transported to the Nez Perce Tribal Hatchery on the Clearwater River in Idaho. The remaining 3,724 fall Chinook salmon were passed upstream. Scales samples were taken from 780 fall Chinook salmon tagged with passive integrated transponder (PIT) tags and collected by the sort-by-code system.

  10. Layer-by-Layer Nanocoatings with Flame Retardant and Oxygen Barrier Properties: Moving Toward Renewable Systems

    E-Print Network [OSTI]

    Laufer, Galina 1985-

    2012-10-23T23:59:59.000Z

    to cotton fabric, all coated fabrics retained their weave structure after being exposed to a vertical flame test, while uncoated cotton was completely destroyed. Micro combustion calorimetry confirmed that coated fabrics exhibited a reduced peak heat release...

  11. Acoustic Modes in Combustors with Complex Impedances and Multidimensional Active Flames

    E-Print Network [OSTI]

    Nicoud, Franck

    Acoustic Modes in Combustors with Complex Impedances and Multidimensional Active Flames F. Nicoud for computing the thermoacoustic modes in combustors. In the case of a nonisothermal reacting medium, the wave

  12. Combustion flame-plasma hybrid reactor systems, and chemical reactant sources

    DOE Patents [OSTI]

    Kong, Peter C

    2013-11-26T23:59:59.000Z

    Combustion flame-plasma hybrid reactor systems, chemical reactant sources, and related methods are disclosed. In one embodiment, a combustion flame-plasma hybrid reactor system comprising a reaction chamber, a combustion torch positioned to direct a flame into the reaction chamber, and one or more reactant feed assemblies configured to electrically energize at least one electrically conductive solid reactant structure to form a plasma and feed each electrically conductive solid reactant structure into the plasma to form at least one product is disclosed. In an additional embodiment, a chemical reactant source for a combustion flame-plasma hybrid reactor comprising an elongated electrically conductive reactant structure consisting essentially of at least one chemical reactant is disclosed. In further embodiments, methods of forming a chemical reactant source and methods of chemically converting at least one reactant into at least one product are disclosed.

  13. Combustion and Flame 150 (2007) 400403 www.elsevier.com/locate/combustflame

    E-Print Network [OSTI]

    Gülder, �mer L.

    velocity pro- file as the gases leave the foam elements. Fig. 1 shows the details of the experimental performed pre- viously with methane [1] and propane [2] diffusion flames at elevated pressures. A constant

  14. Layer-by-Layer Nanocoatings with Flame Retardant and Oxygen Barrier Properties: Moving Toward Renewable Systems 

    E-Print Network [OSTI]

    Laufer, Galina 1985-

    2012-10-23T23:59:59.000Z

    to cotton fabric, all coated fabrics retained their weave structure after being exposed to a vertical flame test, while uncoated cotton was completely destroyed. Micro combustion calorimetry confirmed that coated fabrics exhibited a reduced peak heat release...

  15. Curl Flame Fractal Rib cage and neck of a Cretaceous plesiosaur (elasmosaur)

    E-Print Network [OSTI]

    Machel, Hans

    Curl Flame Fractal Rib cage and neck of a Cretaceous plesiosaur (elasmosaur) Fretted terrain (unit of Gusev Crater, Mars narrow channels scarp narrow ridge Basin Floor Assemblage Basin oor unit 1--Forms

  16. Combustion and Flame 139 (2004) 90105 www.elsevier.com/locate/jnlabr/cnf

    E-Print Network [OSTI]

    Aggarwal, Suresh K.

    2004-01-01T23:59:59.000Z

    . Barlow and Carter [1] investigated experimentally the effects of temperature and mixture fraction on NOx formed experimental and numerical investigations on NOx emissions from turbulent propane diffusion flames stabilized lean premixed methane­air

  17. Numerical simulations of perforated plate stabilized premixed flames with detailed chemistry

    E-Print Network [OSTI]

    Kedia, Kushal Sharad

    2010-01-01T23:59:59.000Z

    The objective of this work is to develop a high efficiency two-dimensional reactive flow solver to investigate perforated-plate stabilized laminar premixed flames. The developed code is used to examine the impact of the ...

  18. Large eddy simulations of premixed turbulent flame dynamics : combustion modeling, validation and analysis

    E-Print Network [OSTI]

    Kewlani, Gaurav

    2014-01-01T23:59:59.000Z

    High efficiency, low emissions and stable operation over a wide range of conditions are some of the key requirements of modem-day combustors. To achieve these objectives, lean premixed flames are generally preferred as ...

  19. Assessment of EEM approach for 3D expanding wrinkled premixed flames

    E-Print Network [OSTI]

    Boyer, Edmond

    /methane, air/propane and air/hydrogen flames are measured at atmo- spheric pressure. An internal combustion engine-like configuration, with an optically accessible cylindrical combustion chamber has also been

  20. Three-dimensional numerical simulations of Rayleigh-Taylor unstable flames in type Ia supernovae

    E-Print Network [OSTI]

    Zingale, M.; Woosley, S.E.; Rendleman, C.A.; Day, M.S.; Bell, J.B.

    2005-01-01T23:59:59.000Z

    Unstable Flames in Type Ia Supernovae M. Zingale 1 , S. E.Subject headings: supernovae: general — white dwarfs —ame in Type Ia supernovae (SNe Ia) is well recognized (M¨

  1. Studies of n-Propanol, iso-Propanol, and Propane Flames

    SciTech Connect (OSTI)

    Veloo, Peter S.; Egolfopoulos, Fokion N.

    2011-01-01T23:59:59.000Z

    The phenomena of propagation and extinction of flames of saturated C{sub 3} alcohols and propane were studied experimentally and numerically in order to assess the effects of the presence and location of the hydroxyl radical in the fuel molecular structure. The experiments were carried out in the counterflow configuration under atmospheric pressure and for unreacted fuel-carrying stream temperature of 343 K. The simulations included detailed descriptions of molecular transport and chemical kinetics using a recently developed kinetic model for C{sub 3} alcohols. The experimental results revealed that the laminar flame speeds and extinction strain rates of n-propanol/air and propane/air flames are close to each other whereas those of iso-propanol/air flames are consistently lower. Similar behavior was observed also for the extinction strain rates of non-premixed n-propanol and iso-propanol flames. It was shown through sensitivity and reaction path analyses that there are two major differences between the intermediates of n-propanol/air and iso-propanol/air flames. In iso-propanol/air flames there are notably higher concentrations of propene whose consumption pathway results in the relatively unreactive allyl radicals, retarding thus the overall reactivity. In n-propanol/air flames there are notably higher concentrations of formaldehyde that reacts readily to form formyl radicals whose subsequent reactions enhance the overall reactivity. The kinetic model used in this study was found to overpredict the experimental results for rich n-propanol/air and propane/air flames. Analysis revealed that those discrepancies are most likely caused by deficiencies in the C{sub 3} alkane kinetics. Through sensitivity analysis, it was determined also that the propagation and extinction of n-propanol/air and iso-propanol/air flames are sensitive largely to hydrogen, carbon monoxide, and C{sub 1}–C{sub 3} kinetics and not to fuel-specific reactions. Finally, the relative sooting propensities of flames of these three fuels were assessed computationally.

  2. OH radical imaging in a DI diesel engine and the structure of the early diffusion flame

    SciTech Connect (OSTI)

    Dec, J.E.; Coy, E.B.

    1996-03-01T23:59:59.000Z

    Laser-sheet imaging studies have considerably advanced our understanding of diesel combustion; however, the location and nature of the flame zones within the combusting fuel jet have been largely unstudied. To address this issue, planar laser-induced fluorescence (PLIF) imaging of the OH radical has been applied to the reacting fuel jet of a direct-injection diesel engine of the ``heavy-duty`` size class, modified for optical access. An Nd:YAG-based laser system was used to pump the overlapping Q{sub 1}9 and Q{sub 2}8 lines of the (1,0) band of the A{yields}X transition at 284.01 nm, while the fluorescent emission from both the (0,O) and (1, I) bands (308 to 320 nm) was imaged with an intensified video camera. This scheme allowed rejection of elastically scattered laser light, PAH fluorescence, and laser-induced incandescence. OH PLIF is shown to be an excellent diagnostic for diesel diffusion flames. The signal is strong, and it is confined to a narrow region about the flame front because the threebody recombination reactions that reduce high flame-front OH concentrations to equilibrium levels occur rapidly at diesel pressures. No signal was evident in the fuel-rich premixed flame regions where calculations and burner experiments indicate that OH concentrations will be below detectable limits. Temporal sequences of OH PLIF images are presented showing the onset and development of the early diffusion flame up to the time that soot obscures the images. These images show that the diffusion flame develops around the periphery of the-downstream portion of the reacting fuel jet about half way through the premixed burn spike. Although affected by turbulence, the diffusion flame remains at the jet periphery for the rest of the imaged sequence.

  3. Soot formation in laminar premixed ethylene/air flames at atmospheric pressure

    SciTech Connect (OSTI)

    Xu, F.; Sunderland, P.B.; Faeth, G.M. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Aerospace Engineering] [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Aerospace Engineering

    1997-03-01T23:59:59.000Z

    Soot formation was studied within laminar premixed ethylene/air flames (C/O ratios of 0.78--0.98) stabilized on a flat-flame burner operating at atmospheric pressure. Measurements included soot volume fractions by both laser extinction and gravimetric methods, temperatures by multiline emission, soot structure by thermophoretic sampling and transmission electric microscopy, major gas species concentrations by sampling and gas chromatography, concentrations of condensable hydrocarbons by gravimetric sampling, and velocities by laser velocimetry. These data were used to find soot surface growth rates and primary soot particle nucleation rates along the axes of the flames. Present measurements of soot surface growth rates were correlated successfully by predictions based on typical hydrogen-abstraction/carbon-addition (HACA) mechanisms of Frenklach and co-workers and Colket and Hall. These results suggest that reduced soot surface growth rates with increasing residence time seen in the present and other similar flames were mainly caused by reduced rates of surface activation due to reduced H atom concentrations as temperatures decrease as a result of radiative heat losses. Primary soot particle nucleation rates exhibited variations with temperature and acetylene concentrations that were similar to recent observations for diffusion flames; however, nucleation rates in the premixed flames were significantly lower than in the diffusion flames for reasons that still must be explained. Finally, predictions of yields of major gas species based on mechanisms from both Frenklach and co-workers and Leung and Lindstedt were in good agreement with present measurements and suggest that H atom concentrations (relevant to HACA mechanisms) approximate estimates based on local thermodynamic equilibrium in the present flames.

  4. Investigation of the processes controlling the flame generation of refractory materials

    SciTech Connect (OSTI)

    Katz, J.L.

    1992-01-01T23:59:59.000Z

    The processes involved in the formation of mixed oxides powders were studied using the counterflow diffusion flame burner. Powders of different morphologies were obtained by varying the flame conditions (temperature, residence time) and the concentration ratio of the oxides precursors. In-situ particle size and number density were determined using dynamic light scattering and 90{degrees} light scattering. A thermophoretic sampling method and a larger scale powder collection device also was used to collect particles, and their size and morphology examined using transmission electron microscopy, X-ray diffraction and surface area measurement by gas absorption (BET). Our emphasis has been on TiO{sub 2}-SiO{sub 2}, SiO{sub 2}-GeO{sub 2} and Al{sub 2}O{sub 3}-TiO{sub 2}. The powders had a core-mantle-like (one oxide coated by the other) at low elevations in the burner and uniform mixture at higher elevations. They form chain-like structures in a low temperature flame and spherical particles in a higher temperature flame. Nanometer sized homogeneous particles of Aluminum Titanate could be obtained using Al(CH{sub 3}){sub 3} and TiCl{sub 4} as precursors both in a hydrogen fueled and a methane fueled counterflow diffusion flame burner, as well as in a hydrogen fueled parallel-flow diffusion flame burner.

  5. Pressure change and transport process on flames formed in a stretched, rotating flow

    SciTech Connect (OSTI)

    Yamamoto, Kazuhiro [Toyohashi Univ. of Technology, Aichi (Japan). Dept. of Mechanical Engineering] [Toyohashi Univ. of Technology, Aichi (Japan). Dept. of Mechanical Engineering

    1999-08-01T23:59:59.000Z

    Flame characteristics in a stretched, rotating flow have been investigated by numerical simulation of tubular laminar flames for lean hydrogen, methane, and propane/air mixtures. Twin planar flames in counterflow have been also simulated for comparison. A fixed inlet velocity at the porous wall of the burner was assumed in all cases, and the cylindrical containing tube (radius R = 9.5 mm) was either maintained stationary or rotated. Results showed that, within the range studied, the flame temperatures always increase monotonically with increasing fuel concentration, and at the same time the reaction zones move outwards. However, while the introduction of rotation also causes a monotonic temperature increase of hydrogen and methane air mixtures, that of a propane/air mixture decreases. The temperature change with rotation becomes smaller with an increase of the fuel concentration. As a consequence of the centrifugal force, {rho}{nu}{sub {theta}}{sup 2}/r, induced by the rotation, a pressure gradient is formed in the cylindrical containing tube, with low pressure along the axis. The pressure gradient at the outer, unburnt edge of the flame reaction zone becomes smaller as the fuel concentration increases. The resultant decreased mass transport by pressure diffusion provides an explanation for part of the above-mentioned temperature change associated with rotation. The remainder of the effect is associated with changed stretch characteristics of the flames.

  6. Autoignited laminar lifted flames of propane in coflow jets with tribrachial edge and mild combustion

    SciTech Connect (OSTI)

    Choi, B.C.; Kim, K.N.; Chung, S.H. [School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-744 (Korea)

    2009-02-15T23:59:59.000Z

    Characteristics of laminar lifted flames have been investigated experimentally by varying the initial temperature of coflow air over 800 K in the non-premixed jets of propane diluted with nitrogen. The result showed that the lifted flame with the initial temperature below 860 K maintained the typical tribrachial structure at the leading edge, which was stabilized by the balance mechanism between the propagation speed of tribrachial flame and the local flow velocity. For the temperature above 860 K, the flame was autoignited without having any external ignition source. The autoignited lifted flames were categorized in two regimes. In the case with tribrachial edge structure, the liftoff height increased nonlinearly with jet velocity. Especially, for the critical condition near blowout, the lifted flame showed a repetitive behavior of extinction and reignition. In such a case, the autoignition was controlled by the non-adiabatic ignition delay time considering heat loss such that the autoignition height was correlated with the square of the adiabatic ignition delay time. In the case with mild combustion regime at excessively diluted conditions, the liftoff height increased linearly with jet velocity and was correlated well with the square of the adiabatic ignition delay time. (author)

  7. Effects of multi-component diffusion and heat release on laminar diffusion flame liftoff

    SciTech Connect (OSTI)

    Li, Zhiliang; Chen, Ruey-Hung [Department of Mechanical, Materials and Aerospace Engineering, University of Central Florida, Orlando, FL 32816-2450 (United States); Phuoc, Tran X. [National Energy Technology Laboratory, Department of Energy, P.O. Box 10940, MS 84-340, Pittsburgh, PA 15261 (United States)

    2010-08-15T23:59:59.000Z

    Numerical simulations were conducted of the liftoff and stabilization phenomena of laminar jet diffusion flames of inert-diluted C{sub 3}H{sub 8} and CH{sub 4} fuels. Both non-reacting and reacting jets were investigated, including multi-component diffusivities and heat release effects (buoyancy and gas expansion). The role of Schmidt number for non-reacting jets was investigated, with no conclusive Schmidt number criterion for liftoff previously arrived at in similarity solutions. The cold-flow simulation for He-diluted CH{sub 4} fuel does not predict flame liftoff; however, adding heat release reaction lead to the prediction of liftoff, which is consistent with experimental observations. Including reaction was also found to improve liftoff height prediction for C{sub 3}H{sub 8} flames, with the flame base location differing from that in the similarity solution - the intersection of the stoichiometric and iso-velocity (equal to 1-D flame speed) is not necessary for flame stabilization (and thus liftoff). Possible mechanisms other than that proposed for similarity solution may better help to explain the stabilization and liftoff phenomena. (author)

  8. Experimental and numerical study of the accuracy of flame-speed measurements for methane/air combustion in a slot burner

    SciTech Connect (OSTI)

    Selle, L.; Ferret, B. [Universite de Toulouse, INPT, UPS, IMFT, Institut de Mecanique des Fluides de Toulouse (France); CNRS, IMFT, Toulouse (France); Poinsot, T. [Universite de Toulouse, INPT, UPS, IMFT, Institut de Mecanique des Fluides de Toulouse (France); CNRS, IMFT, Toulouse (France); CERFACS, Toulouse (France)

    2011-01-15T23:59:59.000Z

    Measuring the velocities of premixed laminar flames with precision remains a controversial issue in the combustion community. This paper studies the accuracy of such measurements in two-dimensional slot burners and shows that while methane/air flame speeds can be measured with reasonable accuracy, the method may lack precision for other mixtures such as hydrogen/air. Curvature at the flame tip, strain on the flame sides and local quenching at the flame base can modify local flame speeds and require corrections which are studied using two-dimensional DNS. Numerical simulations also provide stretch, displacement and consumption flame speeds along the flame front. For methane/air flames, DNS show that the local stretch remains small so that the local consumption speed is very close to the unstretched premixed flame speed. The only correction needed to correctly predict flame speeds in this case is due to the finite aspect ratio of the slot used to inject the premixed gases which induces a flow acceleration in the measurement region (this correction can be evaluated from velocity measurement in the slot section or from an analytical solution). The method is applied to methane/air flames with and without water addition and results are compared to experimental data found in the literature. The paper then discusses the limitations of the slot-burner method to measure flame speeds for other mixtures and shows that it is not well adapted to mixtures with a Lewis number far from unity, such as hydrogen/air flames. (author)

  9. and 19% of the stomachs of late-lifted fish were Food of the striped bass at Holyoke Dam was

    E-Print Network [OSTI]

    Kaplan turbine at a low-head hydroelectric dam. North Am. J. Fish. Manage. 5:33-38. HOLLIS, E. H. 1952

  10. The Dalles Dam, Columbia River: Spillway Improvement CFD Study

    SciTech Connect (OSTI)

    Cook, Chris B.; Richmond, Marshall C.; Serkowski, John A.

    2006-06-01T23:59:59.000Z

    This report documents development of computational fluid dynamics (CFD) models that were applied to The Dalles spillway for the US Army Corps of Engineers, Portland District. The models have been successfully validated against physical models and prototype data, and are suitable to support biological research and operations management. The CFD models have been proven to provide reliable information in the turbulent high-velocity flow field downstream of the spillway face that is typically difficult to monitor in the prototype. In addition, CFD data provides hydraulic information throughout the solution domain that can be easily extracted from archived simulations for later use if necessary. This project is part of an ongoing program at the Portland District to improve spillway survival conditions for juvenile salmon at The Dalles. Biological data collected at The Dalles spillway have shown that for the original spillway configuration juvenile salmon passage survival is lower than desired. Therefore, the Portland District is seeking to identify operational and/or structural changes that might be implemented to improve fish passage survival. Pacific Northwest National Laboratory (PNNL) went through a sequence of steps to develop a CFD model of The Dalles spillway and tailrace. The first step was to identify a preferred CFD modeling package. In the case of The Dalles spillway, Flow-3D was as selected because of its ability to simulate the turbulent free-surface flows that occur downstream of each spilling bay. The second step in development of The Dalles CFD model was to assemble bathymetric datasets and structural drawings sufficient to describe the dam (powerhouse, non-overflow dam, spillway, fish ladder entrances, etc.) and tailrace. These datasets are documented in this report as are various 3-D graphical representations of The Dalles spillway and tailrace. The performance of the CFD model was then validated for several cases as the third step. The validated model was then applied to address specific SIS design questions. Specifically, the CFD models were used to evaluate flow deflectors, baffle block removal and the effects of spillwalls. The CFD models were also used to evaluate downstream differences at other locations, such as at the Highway 197 bridge piers and Oregon shore islands, due to alterations in spill pattern. CFD model results were analyzed to quantitatively compare impacts of the spillwall that has subsequently been constructed between bays 6 and 7. CFD model results provided detailed information about how the spillwall would impact downstream flow patterns that complemented results from the 1:80 scale physical model. The CFD model was also used to examine relative differences between the juvenile spill pattern used in previous years and the anticipated spill pattern that will be applied once the wall is complete. In addition, the CFD model examined velocity magnitudes over the downstream basalt shelf to investigate potential for erosion under high flow conditions (e.g., 21 kcfs/bay for bays 1 through 6) with the spillwall in place. Several appendices follow the results and discussion sections of this report. These appendices document the large number of CFD simulations that have been performed by PNNL; both spillway improvement study (SIS) related and those performed for related biological tests.

  11. Evaluation of Behavioral Guidance Structure on Juvenile Salmonid Passage and Survival at Bonneville Dam in 2009

    SciTech Connect (OSTI)

    Faber, Derrek M.; Ploskey, Gene R.; Weiland, Mark A.; Deng, Zhiqun; Hughes, James S.; Kim, Jin A.; Fu, Tao; Fischer, Eric S.; Monter, Tyrell J.; Skalski, J. R.

    2011-03-01T23:59:59.000Z

    Pacific Northwest National Laboratory (PNNL) conducted an acoustic-telemetry study at Bonneville Dam in 2009 to evaluate the effects of a behavioral guidance structure (BGS) in the Bonneville Dam second powerhouse forebay on fish passage and survival through the second powerhouse (B2), the dam as a whole, and through the first powerhouse and spillway combined. The BGS was deployed to increase the survival of fish passing through B2 by increasing the percentage of outmigrating smolts entering the B2 Corner Collector (B2CC)—a surface flow outlet known to be a relatively benign route for downstream passage at this dam. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. Study results indicated that having turbine 11 in service is important for providing flow conditions that are comparable to those observed in pre-BGS years (2004 and 2005) and in 2008. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

  12. Transfer function characteristics of bluff-body stabilized, conical V-shaped premixed turbulent propane-air flames

    SciTech Connect (OSTI)

    Chaparro, Andres; Landry, Eric; Cetegen, Baki M. [Mechanical Engineering Department, University of Connecticut, 191 Auditorium Road, Storrs, CT 06269-3139 (United States)

    2006-04-15T23:59:59.000Z

    The response of bluff-body stabilized conical V-shaped premixed flames to periodic upstream velocity oscillations was characterized as a function of oscillation frequency, mean flow velocity, and equivalence ratio. The flame heat release response to the imposed velocity oscillations was determined from the CH* chemiluminescence captured by two photomultiplier (PMT) detectors at a wavelength of 430 nm. One of the PMTs viewed flame radiation in a 10-mm horizontal slice, 50 mm above the bluff-body. The second PMT observed the overall flame radiation. The flame transfer function characteristics were determined from the spectral analysis of the velocity and PMT signals. It was found that the flame heat release amplitude response is confined to low-frequency excitation below a Strouhal number of 4. The phase relationship of the transfer function for these turbulent flames was evaluated using the signal from the spatially masked PMT. The transfer function estimate based on these data exhibits second-order characteristics with a phase lag between the velocity and heat release signals. The localized heat-release response contains frequencies that are multiples of the excitation frequency, suggesting splitting and tilting of flame structures as well as some nonlinear effects. Increase of flame equivalence ratio from lean toward stoichiometric resulted in slight amplification of the high-frequency response. (author)

  13. Measurements and modeling of soot formation and radiation in microgravity jet diffusion flames

    SciTech Connect (OSTI)

    Ku, J.C.; Tong, L. [Wayne State Univ., Detroit, MI (United States). Mechanical Engineering Dept.; Greenberg, P.S. [NASA Lewis Research Center, Cleveland, OH (United States). Microgravity Combustion Branch

    1996-12-31T23:59:59.000Z

    This is a computational and experimental study for soot formation and radiative heat transfer in jet diffusion flames under normal gravity (1-g) and microgravity (0-g) conditions. Instantaneous soot volume fraction maps are measured using a full-field imaging absorption technique developed by the authors. On modeling, the authors have coupled flame structure and soot formation models with detailed radiation transfer calculations. Favre-averaged boundary layer equations with a k-e-g turbulence model are used to predict the flow field, and a conserved scalar approach with an assumed {beta}-pdf are used to predict gaseous species mole fraction. Scalar transport equations are used to describe soot volume fraction and number density distributions, with formation and oxidation terms modeled by one-step rate equations and thermophoretic effects included. An energy equation is included to couple flame structure and radiation analyses through iterations, neglecting turbulence-radiation interactions. The YIX solution for a finite cylindrical enclosure is used for radiative heat transfer calculations. The spectral absorption coefficient for soot aggregates is calculated from the Rayleigh solution using complex refractive index data from a Drude-Lorentz model. The exponential-wide-band model is used to calculate the spectral absorption coefficient for H{sub 2}O and CO{sub 2}. Predicted soot volume fraction and temperature results agree well with published data for a normal gravity co-flow laminar flames and turbulent jet flames. Predicted soot volume fraction results also agree with the data for 1-g and 0-g laminar jet flames as well as 1-g turbulent jet flames.

  14. Flame structure of wall-impinging diesel fuel sprays injected by group-hole nozzles

    SciTech Connect (OSTI)

    Gao, Jian; Moon, Seoksu; Nishida, Keiya; Matsumoto, Yuhei [Department of Mechanical System Engineering, University of Hiroshima, Higashi-Hiroshima, 739-8527 (Japan); Zhang, Yuyin [Department of Mechanical Engineering, Tokyo Denki University, Tokyo, 101-8457 (Japan)

    2009-06-15T23:59:59.000Z

    This paper describes an investigation of the flame structure of wall-impinging diesel sprays injected by group-hole nozzles in a constant-volume combustion vessel at experimental conditions typical of a diesel engine. The particular emphasis was on the effect of the included angle between two orifices (0-15 deg. in current study) on the flame structure and combustion characteristics under various simulated engine load conditions. The laser absorption scattering (LAS) technique was applied to analyze the spray and mixture properties. Direct flame imaging and OH chemiluminescence imaging were utilized to quantify the ignition delay, flame geometrical parameters, and OH chemiluminescence intensity. The images show that the asymmetric flame structure emerges in wall-impinging group-hole nozzle sprays as larger included angle and higher engine load conditions are applied, which is consistent with the spray shape observed by LAS. Compared to the base nozzle, group-hole nozzles with large included angles yield higher overall OH chemiluminescence intensity, wider flame area, and greater proportion of high OH intensity, implying the better fuel/air mixing and improved combustion characteristics. The advantages of group-hole nozzle are more pronounced under high load conditions. Based on the results, the feasibility of group-hole nozzle for practical direct injection diesel engines is also discussed. It is concluded that the asymmetric flame structure of a group-hole nozzle spray is favorable to reduce soot formation over wide engine loads. However, the hole configuration of the group-hole nozzle should be carefully considered so as to achieve proper air utilization in the combustion chamber. Stoichiometric diesel combustion is another promising application of group-hole nozzle. (author)

  15. Effects of the Georgia flood of `94 on Lake Blackshear Dam

    SciTech Connect (OSTI)

    Findlay, R.C.; Northrop, J.H. [Northrop, Devine & Tarbell, Inc., Portland, ME (United States); Crisp, R.L. Jr. [and others

    1995-12-31T23:59:59.000Z

    Tropical Storm Alberto produced record rainfall in central Georgia in early July, 1994. The area drains into Lake Blackshear, formed in the Flint River by Lake Blackshear Dam. The level of the lake rose 3.5 m (11.5 ft) above normal and caused the worst flooding of the area in recorded history. The north embankment of the dam was overtopped, causing a 215 m (700 ft) breach. Prior to the breach, a few concentrated boils were observed in the tailwater downstream of the non-breached portion of the dam. This portion remained intact through the flood, but the presence of the boils raised questions regarding its integrity. The effects of the flood on the north embankment are discussed, as well as the geotechnical investigation conducted to assess subsurface conditions at the breach and intact portions and the plan for remediation.

  16. Hungry Horse Dam Fisheries Mitigation Implementation Plan, 1990-2003 Progress (Annual) Report.

    SciTech Connect (OSTI)

    Montana Department of Fish, Wildlife and Parks; Confederated Salish and Kootenai Tribes

    1993-03-10T23:59:59.000Z

    In this document the authors present mitigation implementation activities to protect and enhance resident fish and aquatic habitat affected by the construction and operation of Hungry Horse Dam. This plan only addresses non-operational actions (mitigation measures that do not affect dam operation) described in the 'Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam' (Mitigation Plan) submitted to the Northwest Power Planning Council (Council) in March 1991 and in accordance with subsequent Council action on that Mitigation Plan. Operational mitigation was deferred for consideration under the Columbia Basin System Operation Review (SOR) process. This document represents an implementation plan considered and conditionally approved by the Council in March of 1993.

  17. Computational Fluid Dynamics Modeling of the John Day Dam Tailrace

    SciTech Connect (OSTI)

    Rakowski, Cynthia L.; Perkins, William A.; Richmond, Marshall C.; Serkowski, John A.

    2010-07-08T23:59:59.000Z

    US Army Corps of Engineers - Portland District required that a two-dimensional (2D) depth-averaged and a three-dimensional (3D) free-surface numerical models to be developed and validated for the John Day tailrace. These models were used to assess potential impact of a select group of structural and operational alternatives to tailrace flows aimed at improving fish survival at John Day Dam. The 2D model was used for the initial assessment of the alternatives in conjunction with a reduced-scale physical model of the John Day Project. A finer resolution 3D model was used to more accurately model the details of flow in the stilling basin and near-project tailrace hydraulics. Three-dimensional model results were used as input to the Pacific Northwest National Laboratory particle tracking software, and particle paths and times to pass a downstream cross section were used to assess the relative differences in travel times resulting from project operations and structural scenarios for multiple total river flows. Streamlines and neutrally-buoyant particles were seeded in all turbine and spill bays with flows. For a Total River of 250 kcfs running with the Fish Passage Plan spill pattern and a spillwall, the mean residence times for all particles were little changed; however the tails of the distribution were truncated for both spillway and powerhouse release points, and, for the powerhouse releases, reduced the residence time for 75% of the particles to pass a downstream cross section from 45.5 minutes to 41.3 minutes. For a total river of 125 kcfs configured with the operations from the Fish Passage Plan for the temporary spillway weirs and for a proposed spillwall, the neutrally-buoyant particle tracking data showed that the river with a spillwall in place had the overall mean residence time increase; however, the residence time for 75% of the powerhouse-released particles to pass a downstream cross section was reduced from 102.4 min to 89 minutes.

  18. Evaluation of a Behavioral Guidance Structure at Bonneville Dam Second Powerhouse including Passage Survival of Juvenile Salmon and Steelhead using Acoustic Telemetry, 2008

    SciTech Connect (OSTI)

    Faber, Derrek M.; Ploskey, Gene R.; Weiland, Mark A.; Deng, Zhiqun; Hughes, James S.; McComas, Roy L.; Kim, Jina; Townsend, R. L.; Fu, Tao; Skalski, J. R.; Fischer, Eric S.

    2010-02-12T23:59:59.000Z

    Summarizes research conducted at Bonneville Dam in 2008 to evaluate a prototype Behavioral Guidance Structure, that was deployed by the US Army Corps of Engineers in an effort to increase survival of outmigrating smolts at Bonneville Dam.

  19. Compliance Monitoring of Yearling Chinook Salmon and Juvenile Steelhead Survival and Passage at John Day Dam, Spring 2011

    SciTech Connect (OSTI)

    Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Weiland, Mark A.; Woodley, Christa M.; Hughes, James S.; Carlson, Thomas J.

    2012-06-01T23:59:59.000Z

    The study was designed to estimate dam passage survival at John Day Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and to provide additional fish passage performance measures at that site as stipulated in the Columbia Basin Fish Accords.

  20. Compliance Monitoring of Yearling Chinook Salmon and Juvenile Steelhead Survival and Passage at John Day Dam, Spring 2011

    SciTech Connect (OSTI)

    Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Weiland, Mark A.; Woodley, Christa M.; Hughes, James S.; Carlson, Thomas J.

    2012-02-01T23:59:59.000Z

    The study was designed to estimate dam passage survival at John Day Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and to provide additional fish passage performance measures at that site as stipulated in the Columbia Basin Fish Accords.

  1. Do impassable dams and flow regulation constrain the distribution of green sturgeon in the Sacramento River, California?

    E-Print Network [OSTI]

    Klimley, A. Peter

    , American River, and Yuba River. While dams block access to about 9% of historically available habitatDo impassable dams and flow regulation constrain the distribution of green sturgeon in the Sacramento River, California? By E. A. Mora1 , S. T. Lindley2 , D. L. Erickson3 and A. P. Klimley4 1 Joint

  2. Compliance Monitoring of Yearling Chinook Salmon and Juvenile Steelhead Survival and Passage at Bonneville Dam, Spring 2011

    SciTech Connect (OSTI)

    Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Carlson, Thomas J.

    2012-03-01T23:59:59.000Z

    The study was designed to estimate dam passage survival at Bonneville Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and to provide additional fish passage performance measures at that site as stipulated in the Columbia Basin Fish Accords.

  3. White Sturgeon Mitigation and Restoration in the Columbia and Snake Rivers Upstream from Bonneville Dam; 2002-2003 Annual Report.

    SciTech Connect (OSTI)

    Ward, David L.; Kern, J. Chris; Hughes, Michele L. (Oregon Department of Fish and Wildlife)

    2004-02-01T23:59:59.000Z

    We report on our progress from April 2002 through March 2003 on determining the effects of mitigative measures on productivity of white sturgeon populations in the Columbia River downstream from McNary Dam, and on determining the status and habitat requirements of white sturgeon populations in the Columbia and Snake rivers upstream from McNary Dam.

  4. Estimating Overall Risk of Dam Failure: Practical Considerations in Combining Failure Probabilities ANCOLD 2003 Risk Workshop Page 1

    E-Print Network [OSTI]

    Bowles, David S.

    combination of probabilities in quantitative risk analysis. Keywords: dam safety, risk analysis, risk for estimating probabilities in dam safety risk analysis both for assessing the risks associated with an existing in the risk analysis model can have a significant influence on the magnitudes of key inputs to decisions about

  5. Compliance Monitoring of Yearling Chinook Salmon and Juvenile Steelhead Survival and Passage at Bonneville Dam, Spring 2011

    SciTech Connect (OSTI)

    Skalski, John R.; Townsend, Richard L.; Seaburg, Adam; Ploskey, Gene R.; Carlson, Thomas J.

    2012-06-07T23:59:59.000Z

    The study was designed to estimate dam passage survival at Bonneville Dam as stipulated by the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp) and to provide additional fish passage performance measures at that site as stipulated in the Columbia Basin Fish Accords.

  6. Apparatus for efficient sidewall containment of molten metal with horizontal alternating magnetic fields utilizing a ferromagnetic dam

    DOE Patents [OSTI]

    Praeg, W.F.

    1997-02-11T23:59:59.000Z

    An apparatus is disclosed for casting sheets of metal from molten metal. The apparatus includes a containment structure having an open side, a horizontal alternating magnetic field generating structure and a ferromagnetic dam. The magnetic field and the ferromagnetic dam contain the molten metal from leaking out side portions of the open side of the containment structure. 25 figs.

  7. Acoustic Telemetry Evaluation of Juvenile Salmonid Passage and Survival at John Day Dam, 2011

    SciTech Connect (OSTI)

    Weiland, Mark A.; Woodley, Christa M.; Ploskey, Gene R.; Hughes, James S.; Hennen, Matthew J.; Kim, Jin A.; Deng, Zhiqun; Fu, Tao; Skalski, J. R.; Townsend, Richard L.; Wagner, Katie A.; Fischer, Eric S.; Duncan, Joanne P.; Batten, G.; Carlson, Thomas J.; Carpenter, Scott M.; Cushing, Aaron W.; Elder, T.; Etherington, D. J.; Johnson, Gary E.; Khan, Fenton; Miracle, Ann L.; Mitchell, T. D.; Prather, K.; Rayamajhi, Bishes; Royer, Ida; Seaburg, Adam; Zimmerman, Shon A.

    2013-06-21T23:59:59.000Z

    This report presents survival, behavioral, and fish passage results for tagged yearling Chinook salmon and juvenile steelhead as part of a survival study conducted at John Day Dam during spring 2011. This study was designed to evaluate the passage and survival of yearling Chinook salmon and juvenile steelhead to assist managers in identifying dam operations for compliance testing as stipulated by the 2008 Federal Columbia River Power System Biological Opinion and the 2008 Columbia Basin Fish Accords. Survival estimates were based on a paired-release survival model.

  8. Acoustic Telemetry Evaluation of Juvenile Salmonid Passage and Survival at John Day Dam, 2010

    SciTech Connect (OSTI)

    Weiland, Mark A.; Woodley, Christa M.; Ploskey, Gene R.; Hughes, James S.; Kim, Jin A.; Deng, Zhiqun; Fu, Tao; Fischer, Eric S.; Skalski, J. R.; Townsend, Richard L.; Duncan, Joanne P.; Hennen, Matthew J.; Wagner, Katie A.; Arntzen, Evan V.; Miller, Benjamin L.; Miracle, Ann L.; Zimmerman, Shon A.; Royer, Ida M.; Khan, Fenton; Cushing, Aaron W.; Etherington, D. J.; Mitchell, T. D.; Elder, T.; Batton, George; Johnson, Gary E.; Carlson, Thomas J.

    2013-05-01T23:59:59.000Z

    This report presents survival, behavioral, and fish passage results for yearling and subyearling Chinook salmon smolts and juvenile steelhead tagged with JSATS acoustic micro-transmitters as part of a survival study conducted at John Day Dam during 2010. This study was designed to evaluate the passage and survival of yearling and subyearling Chinook salmon and juvenile steelhead to assist managers in identifying dam operations for compliance testing as stipulated by the 2008 Federal Columbia River Power System Biological Opinion and the 2008 Columbia Basin Fish Accords. Survival estimates were based on a single-release survival estimate model.

  9. A biometrical evaluation of relationships between dam weight and progeny preweaning performance in beef cattle

    E-Print Network [OSTI]

    Smith, Gerald Max

    1968-01-01T23:59:59.000Z

    A BIDMETRICA' EVALUA11ON Oi. RELATIONSV, IPS BFT'AEENI DAM W. IGHT AND PROGENY nREIfEANING PERFORMANCE IN BEEF CATILE A Thesis by GFRALD MAX SMITH Suf&mitfed to the Cradua'te Colleae of Texas Aiild University in pardial f. . lfillmen...& I TH App oved as Io style and content by: (Head of Doper t nant ) I Pie p1 be I' ) AoGnst ISSB ABS'IRAC) A P&ometricaI Bvaluation o~ Relationships Betweor Dam lrieight and Progeny Preweaning Performance in Beef Cattle. (Augusl I"GB) Gerald...

  10. Reaction of the dams behind the Toktoguol and Kurpsa hydroelectric power plants to repeated earthquakes

    SciTech Connect (OSTI)

    Marchuk, A.N.; Umralin, K.B.; Moldebehov, Z.I. [and others

    1994-11-01T23:59:59.000Z

    The region where the chain of Naryn hydroelectric power plants are located in the Kyrgyzstan Republic is a seismically active area of Central Tien-Shan and is comparatively well known in seismological respects. No means of measuring the dams themselves, however, were ever incorporated as an instrumental base of investigation. The seismometric possibilities of embedded monitoring-measuring apparatus were disclosed by O.Yu. Schmidt Institute of Earth Physics and have made is possible to evaluate the reactions of dams to seismic effects and of excited seismicity, when residual deformations due to repeated tremors of different force and direction are accumulated over an extended period of time.

  11. The effect of raft removal and dam construction on the lower Colorado River, Texas

    E-Print Network [OSTI]

    Hartopo

    1991-01-01T23:59:59.000Z

    THE EFFECT OF RAFT REMOVAL AND DAM CONSTRUCTION ON THE LOWER COLORADO RIVER, TEXAS A Thesis by HARTOPO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for degree of MASTER... OF SCIENCE May 1991 Major Subject: Geology TIIE EFFECT OI RAII' REMOVAL AND DAM CONSTRUCTION ON TI-IE LOWER COLORADO RIVER, TEXAS A Thesis by I IARTOPO Approved as to styic and content by: Christ her C. Mathewson (Chair of Committee) John R...

  12. Relationship of the weaning weight of beef calves to the size of their dams

    E-Print Network [OSTI]

    Tanner, James Edward

    1964-01-01T23:59:59.000Z

    of MASTER OF SCIENCE August 1964 Major Subject; Animal Breeding REIATIONSHIP OF THE WEANING WEIGHT OF BEEF CALVES TO THE SIZE OF THEIR DAMS A Thesis By JAMES EDWARD TANNER Approved as to style and content by: ';/ . (Chatrman o Committee) (Head... of age of dam within weight groups of Angus cows 20 Analyses of covariance of 200-day weight (lb. ? of Angus calves. Estimated least-squares constants for 200-day weight (lb. ) of Angus calves Least-squares means of 200-day weight (lb. ) of Angus...

  13. Survival of Juvenile Chinook Salmon Passing the Bonneville Dam Spillway in 2007

    SciTech Connect (OSTI)

    Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Zimmerman, Shon A.; Durham, Robin E.; Fischer, Eric S.; Kim, Jina; Townsend, R. L.; Skalski, J. R.; Buchanan, Rebecca A.; McComas, Roy L.

    2008-12-01T23:59:59.000Z

    The U.S. Army Corps of Engineers Portland District (CENWP) funds numerous evaluations of fish passage and survival on the Columbia River. In 2007, the CENWP asked Pacific Northwest National Laboratory to conduct an acoustic telemetry study to estimate the survival of juvenile Chinook salmon passing the spillway at Bonneville Dam. This report documents the study results which are intended to be used to improve the conditions juvenile anadromous fish experience when passing through the dams that the Corps operates on the river.

  14. Survival and Passage of Yearling and Subyearling Chinook Salmon and Steelhead at The Dalles Dam, 2010

    SciTech Connect (OSTI)

    Johnson, Gary E.; Skalski, J. R.; Carlson, Thomas J.; Ploskey, Gene R.; Weiland, Mark A.; Deng, Zhiqun; Fischer, Eric S.; Hughes, James S.; Khan, Fenton; Kim, Jin A.; Townsend, Richard L.

    2011-12-01T23:59:59.000Z

    The acoustic telemetry study reported here was conducted by researchers at Pacific Northwest National Laboratory (PNNL) and the University of Washington (UW) for the U.S. Army Corps of Engineers, Portland District (USACE). The purpose of the study was to estimate dam passage survival and other performance measures for yearling and subyearling Chinook salmon and steelhead at The Dalles Dam as stipulated by the 2008 Biological Opinion on operation of the Federal Columbia River Power System (FCRPS) and 2008 Columbia Basin Fish Accords.

  15. Blowoff characteristics of bluff-body stabilized conical premixed flames with upstream spatial mixture gradients and velocity oscillations

    SciTech Connect (OSTI)

    Chaudhuri, Swetaprovo; Cetegen, Baki M. [Mechanical Engineering Department, University of Connecticut, Storrs, CT 06269-3139 (United States)

    2008-06-15T23:59:59.000Z

    This experimental study concerns determination of blowoff equivalence ratios for lean premixed conical flames for different mixture approach velocities ranging from 5 to 16 m/s in the presence of spatial mixture gradients and upstream velocity modulation. Conical flames were anchored on a disk-shaped bluff body that was attached to a central rod in the burner nozzle. A combustible propane-air mixture flowed through a converging axisymmetric nozzle with a concentric insert, allowing radial mixture variation by tailoring the composition in the inner and outer parts of the nozzle. The radial mixture profiles were characterized near the location of the flame holder by laser Rayleigh light scattering. Additionally, a loudspeaker at the nozzle base allowed introduction of periodic velocity oscillations with an amplitude of 9% of the mean flow velocity up to a frequency of 350 Hz. The flame blowoff equivalence ratio was experimentally determined by continuously lowering the fuel flow rates and determining the flame detachment point from the flame holder. Flame detachment was detected by a rapid reduction of CH* emission from the flame base imaged by a photomultiplier detector. It was found that the flame blowoff is preceded by progressive narrowing of the flame cone for the case of higher inner jet equivalence ratios. In this case, the fuel-lean outer flow cannot sustain combustion, and clearly this is not a good way of operating a combustor. Nevertheless, the overall blowoff equivalence ratio is reduced by inner stream fuel enrichment. A possible explanation for this behavior is given based on the radial extent of the variable-equivalence-ratio mixture burning near the flame stabilization region. Fuel enrichment in the outer flow was found to have no effect on blowoff as compared to the case of uniform mixture. The results were similar for the whole range of mean flow velocities and upstream excitation frequencies. (author)

  16. Risk Assessment Required In The Framework Of New French Regulation hhdTTjjhkljdjjsgshjhfsdkjhskslsl;s;s;;s;;s;;sjsjkjffffrtttttttfggjfgjgkfkjkjf fffffjfjjfkkfjjjOn Dams

    E-Print Network [OSTI]

    Boyer, Edmond

    to carry out a risk analysis to identify all failure modes that may occur on dam structure and hydraulic on the single dam are identified and managed. The risk of a dam failure must be studied, for example duringTTjjhkljdjjsgshjhfsdkjhskslsl;s;s;;s;;s;;sjsjkjffffrtttttttfggjfgjgkfkjkjf fffffjfjjfkkfjjjOn Dams 2(14pt) Methodology Developed By INERIS T. Balouin, A. Lahoz, C. Bolvin & Y. Flauw

  17. 1. Go on top of the check-dam and survey the water-shed, i.e., the upstream part from which water ows into the storage.

    E-Print Network [OSTI]

    Sohoni, Milind

    TD 603 1. Go on top of the check-dam and survey the water-shed, i.e., the upstream part from which water ows into the storage. 2. What is the storage in the dam (in cu.m.)? 3. What is the length and depth of the dam? What is its structure and cost? How much time did it take to build the dam? 4. Where

  18. Effect of a uniform electric field on soot in laminar premixed ethylene/air flames

    SciTech Connect (OSTI)

    Wang, Y.; Yao, Q. [Key Laboratory of Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, 100084 Beijing (China); Nathan, G.J. [School of Mechanical Engineering, Centre for Energy Technology, The University of Adelaide, S.A. 5005 (Australia); Alwahabi, Z.T.; King, K.D.; Ho, K. [School of Chemical Engineering, Centre for Energy Technology, The University of Adelaide, S.A. 5005 (Australia)

    2010-07-15T23:59:59.000Z

    The effect of a nominally uniform electric field on the initially uniform distribution of soot has been assessed for laminar premixed ethylene/air flames from a McKenna burner. An electrophoretic influence on charged soot particles was measured through changes to the deposition rate of soot on the McKenna plug, using laser extinction (LE). Soot volume fraction was measured in situ using laser-induced incandescence (LII). Particle size and morphologies were assessed through ex situ transmission electron microscopy (TEM) using thermophoretic sampling particle diagnostics (TSPD). The results show that the majority of these soot particles are positively charged. The presence of a negatively charged plug was found to decrease the particle residence times in the flame and to influence the formation and oxidation progress. A positively charged plug has the opposite effect. The effect on soot volume fraction, particles size and morphology with electric field strength is also reported. Flame stability was also found to be affected by the presence of the electric field, with the balance of the electrophoretic force and drag force controlling the transition to unstable flame flicker. The presence of charged species generated by the flame was found to reduce the dielectric field strength to one seventh that of air. (author)

  19. Soot formation in laminar premixed methane/oxygen flames at atmospheric pressure

    SciTech Connect (OSTI)

    Xu, F.; Lin, K.C.; Faeth, G.M. [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Aerospace Engineering] [Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Aerospace Engineering

    1998-10-01T23:59:59.000Z

    Flame structure and soot formation were studied within soot-containing laminar premixed methane/oxygen flames at atmospheric pressure. The following measurements were made: soot volume fractions by laser extinction, soot temperatures by multiline emission, gas temperatures (where soot was absent) by corrected fine-wire thermocouples, soot structure by thermophoretic sampling and transmission electron microscope (TEM), major gas species concentrations by sampling and gas chromatography, and gas velocities by laser velocimetry. Present measurements of gas species concentrations were in reasonably good agreement with earlier measurements due to Ramer et al. as well as predictions based on the detailed mechanisms of Frenklach and co-workers and Leung and Lindstedt; the predictions also suggest that H atom concentrations are in local thermodynamic equilibrium throughout the soot formation region. Using this information, it was found that measured soot surface growth rates could be correlated successfully by predictions based on the hydrogen-abstraction/carbon-addition (HACA) mechanisms of both Frenklach and co-workers and Colket and Hall, extending an earlier assessment of these mechanisms for premixed ethylene/air flames to conditions having larger H/C ratios and acetylene concentrations. Measured primary soot particle nucleation rates were somewhat lower than the earlier observations for laminar premixed ethylene/air flames and were significantly lower than corresponding rates in laminar diffusion flames, for reasons that still must be explained.

  20. Reduction of soot emissions by iron pentacarbonyl in isooctane diffusion flames

    SciTech Connect (OSTI)

    Kim, K.B.; Masiello, K.A.; Hahn, D.W. [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL 32611 (United States)

    2008-07-15T23:59:59.000Z

    Light-scattering measurements, in situ laser-induced fluorescence, and thermophoretic sampling with transmission electron microscopy (TEM) analysis, were performed in laboratory isooctane diffusion flames seeded with 4000 ppm iron pentacarbonyl. These measurements allowed the determination of the evolution of the size, number density, and volume fraction of soot particles through the flame. Comparison to unseeded flame data provided a detailed assessment of the effects of iron addition on soot particle inception, growth, and oxidation processes. Iron was found to produce a minor soot-enhancing effect at early residence times, while subsequent soot particle growth was largely unaffected. It is concluded that primarily elemental iron is incorporated within the soot particles during particle inception and growth. However, iron addition was found to enhance the rate of soot oxidation during the soot burnout regime, yielding a two-thirds reduction in overall soot emissions. In situ spectroscopic measurements probed the transient nature of elemental iron throughout the flame, revealing significant loss of elemental iron, presumably to iron oxides, with increasing flame residence, suggesting catalysis of soot oxidation via iron oxide species. (author)

  1. Soot suppression by ferrocene in laminar ethylene/air nonpremixed flames

    SciTech Connect (OSTI)

    Zhang, J.; Megaridis, C.M. [Univ. of Illinois, Chicago, IL (United States). Dept. of Mechanical Engineering] [Univ. of Illinois, Chicago, IL (United States). Dept. of Mechanical Engineering

    1996-06-01T23:59:59.000Z

    An experimental investigation is presented on the origin of the soot suppressing role of ferrocene additive in laminar, coannular, ethylene/air nonpremixed flames. The conditions examined involve laminar flames operating above and below their smoke point. In-flame diagnostics are employed to discern the interaction between the soot matrix and additive combustion products. The data presented in a previous study, as produced by thermophoretic sampling, transmission electron microscopy and high-resolution microanalysis techniques, are supplemented by soot volume fraction, temperature, and soot primary size measurements to unravel the mechanisms through which ferrocene combustion products influence soot formation processes. Furthermore, Z-contrast scanning/transmission electron microscopy is used to examine the over-fire aerosol and, in turn, provide insight on the fine-scale dispersion of iron fragments within the carbonaceous soot matrix. It is shown that ferrocene seeding of the fuel stream accelerates the particular inception mechanisms, but does not influence soot loadings when soot growth is dominant. Ferrocene is also found to enhance soot oxidation rates near the flame terminus. It is concluded that the fine-scale incorporation of iron compounds within the soot matrix is a primary factor for the soot suppressing role of ferrocene in nonpremixed flames.

  2. In situ flame chemistry tracing by imaging photoelectron photoion coincidence spectroscopy

    SciTech Connect (OSTI)

    Oßwald, P.; Köhler, M. [German Aerospace Center (DLR) – Institute of Combustion Technology, Stuttgart 70569 (Germany)] [German Aerospace Center (DLR) – Institute of Combustion Technology, Stuttgart 70569 (Germany); Hemberger, P.; Bodi, A.; Gerber, T. [Molecular Dynamics Group, Paul Scherrer Institut, CH-5232 Villigen (Switzerland)] [Molecular Dynamics Group, Paul Scherrer Institut, CH-5232 Villigen (Switzerland); Bierkandt, T.; Akyildiz, E.; Kasper, T., E-mail: tina.kasper@uni-due.de [Mass Spectrometry in Reactive Flows - Thermodynamics (IVG), University of Duisburg-Essen, Duisburg (Germany)

    2014-02-15T23:59:59.000Z

    Adaptation of a low-pressure flat flame burner with a flame-sampling interface to the imaging photoelectron photoion coincidence spectrometer (iPEPICO) of the VUV beamline at the Swiss Light Source is presented. The combination of molecular-beam mass spectrometry and iPEPICO provides a new powerful analytical tool for the detailed investigation of reaction networks in flames. First results demonstrate the applicability of the new instrument to comprehensive flame diagnostics and the potentially high impact for reaction mechanism development for conventional and alternative fuels. Isomer specific identification of stable and radical flame species is demonstrated with unrivaled precision. Radical detection and identification is achieved for the initial H-abstraction products of fuel molecules as well as for the reaction controlling H, O, and OH radicals. Furthermore, quantitative evaluation of changing species concentrations during the combustion process and the applicability of respective results for kinetic model validation are demonstrated. Utilization of mass-selected threshold photoelectron spectra is shown to ensure precise signal assignment and highly reliable spatial profiles.

  3. Experimental and modeling investigation of aromatic and polycyclic aromatic hydrocarbon formation in a premixed ethylene flame

    SciTech Connect (OSTI)

    Castaldi, M.J.; Marinov, N.M.; Melius, C.F. [and others

    1996-02-01T23:59:59.000Z

    Experimental and detailed chemical kinetic modeling has been performed to investigate aromatic and polyaromatic hydrocarbon formation pathways in a rich, sooting, ethylene-oxygen-argon premixed flame. An atmospheric pressure, laminar flat flame operated at an equivalence ratio of 2.5 was used to acquire experimental data for model validation. Gas composition analysis was conducted by an on-line gas chromatograph/mass spectrometer (GC/MS) technique. Measurements were made in the flame and post-flame zone for a number of low molecular weight species, aliphatics, aromatics and polycyclic aromatic hydrocarbons (PAHs) ranging from two to five-aromatic fused rings. The modeling results show the key reaction sequences leading to aromatic and polycyclic aromatic hydrocarbon growth involve the combination of resonantly stabilized radicals. In particular, propargyl and 1-methylallenyl combination reactions lead to benzene and methyl substituted benzene formation, while polycyclic aromatics are formed from cyclopentadienyl radicals and fused rings that have a shared C{sub 5} side structure. Naphthalene production through the reaction step of cyclopentadienyl self-combination and phenanthrene formation from indenyl and cyclopentadienyl combination were shown to be important in the flame modeling study. The removal of phenyl by O{sub 2} leading to cyclopentadienyl formation is expected to play a pivotal role in the PAH or soot precursor growth process under fuel-rich oxidation conditions.

  4. Flame acceleration and DDT in channels with obstacles: Effect of obstacle spacing

    SciTech Connect (OSTI)

    Gamezo, Vadim N.; Oran, Elaine S. [Laboratory for Computational Physics and Fluid Dynamics, Naval Research Laboratory, Washington, DC 20375 (United States); Ogawa, Takanobu [Department of Mechanical Engineering, Seikei University, Kichijoji-Kitamachi, Musashino-shi, Tokyo, 180-8633 (Japan)

    2008-10-15T23:59:59.000Z

    We study flame acceleration and deflagration-to-detonation transition (DDT) in obstructed channels using 2D reactive Navier-Stokes numerical simulations. The energy release rate for the stoichiometric hydrogen-air mixture is modeled by one-step Arrhenius kinetics. Computations performed for channels with symmetrical and staggered obstacle configurations show two main effects of obstacle spacing S. First, more obstacles per unit length create more perturbations that increase the flame surface area more quickly, and therefore the flame speed grows faster. Second, DDT occurs more easily when the obstacle spacing is large enough for Mach stems to form between obstacles. These two effects are responsible for three different regimes of flame acceleration and DDT observed in simulations: (1) Detonation is ignited when a Mach stem formed by the diffracting shock reflecting from the side wall collides with an obstacle, (2) Mach stems do not form, and the detonation is not ignited, and (3) Mach stems do not form, but the leading shock becomes strong enough to ignite a detonation by direct collision with the top of an obstacle. Regime 3 is observed for small S and involves multiple isolated detonations that appear between obstacles and play a key role in final stages of flame and shock acceleration. For Regime 1 and staggered obstacle configurations, we observe resonance phenomena that significantly reduce the DDT time when S/2 is comparable to the channel width. Effects of imposed symmetry and stochasticity on DDT phenomena are also considered. (author)

  5. Aromatics oxidation and soot formation in flames. Progress report, August 15, 1990--August 14, 1993

    SciTech Connect (OSTI)

    Howard, J.B.; Pope, C.J.; Shandross, R.A.; Yadav, T.

    1993-04-01T23:59:59.000Z

    This project is concerned with the kinetics and mechanisms of aromatics oxidation and soot and fullerenes formation in flames. The scope includes detailed measurements of profiles of stable and radical species concentrations in low-pressure one-dimensional premixed flames. Intermediate species identifications and mole fractions, fluxes, and net reaction rates calculated from the measured profiles are used to test postulated reaction mechanisms. Particular objectives are to identify, and to confirm or determine rate constants for, the main benzene oxidation reactions in flames, and to characterize soot and fullerenes and their formation mechanisms and kinetics. Stable and radical species profiles in the aromatics oxidation study are measured using molecular beam sampling with on-line mass spectrometry. The rate of soot formation measured by conventional optical techniques is found to support the hypotheses that particle inception occurs through reactive coagulation of high molecular weight PAH in competition with destruction by OHattack, and that the subsequent growth of the soot mass occurs through addition reactions of PAH and C{sub 2}H{sub 2} with the soot particles. During the first year of this reporting period, fullerenes C{sub 60} and C{sub 70} in substantial quantities were found in the flames being studied. The fullerenes were recovered, purified and spectroscopically identified. The yields of C{sub 60} and C{sub 70} were then determined over ranges of conditions in low-pressure premixed flames of benzene and oxygen.

  6. The Implications of Horizontal and Complete Dam Removals on the Downstream Channel Bed Joanna Crowe Curran (curran@virginia.edu) and Kristen Cannatelli

    E-Print Network [OSTI]

    Curran, Joanna C.

    accessible by reducing or eliminating the costs associated with unnecessary dredging of uncontaminated stakeholder concerns, and reduce the economic expenditure of dredging that is associated with dam removal stage II ­ scour filled in Flow Woolen Mills (VA): dredging with dam removal Embrey Dam (VA): Complete

  7. d:\\activepdf\\uploadfolder\\$asq1rr04-4144-212200461042pm.doc Page 1 Erosional narrowing after dam removal: Theory and numerical model

    E-Print Network [OSTI]

    Parker, Gary

    of a dam that is filled with sediment. A channel incises into the deposit after failure of the leadingd:\\activepdf\\uploadfolder\\$asq1rr04-4144-212200461042pm.doc Page 1 Erosional narrowing after dam phenomenon herein called "erosional narrowing". This occurs immediately after the sudden removal of a dam

  8. The Dam1 kinetochore complex harnesses microtubule dynamics to produce force and Charles L. Asbury, Daniel R. Gestaut, Andrew F. Powers, Andrew D. Franck, and Trisha N. Davis

    E-Print Network [OSTI]

    Davis, Trisha N.

    movement The Dam1 kinetochore complex harnesses microtubule dynamics to produce force and Charles L.pnas.org/misc/reprints.shtml To order reprints, see: Notes: #12;The Dam1 kinetochore complex harnesses microtubule dynamics to produce are uncertain, and the mechanism of MT-dependent force production is unknown. Recent work suggests that the Dam1

  9. The day the Dam Busters returned... in Canada Tom Chivers learns why Channel 4 asked engineers to rebuild Barnes Wallis's bouncing bomb.

    E-Print Network [OSTI]

    Talbot, James P.

    The day the Dam Busters returned... in Canada Tom Chivers learns why Channel 4 asked engineers to rebuild Barnes Wallis's bouncing bomb. Explosive: a scene from Channel 4?s new documentary about the Dam, at scale, under a plane, building a dam and blowing it up, is much more of an engineering exercise than

  10. Avalanche protection dam of Cialancier in Saint Etienne de Tine : From 2D digital modeling to the start of the onsite work

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Avalanche protection dam of Cialancier in Saint Etienne de Tinée : From 2D digital modeling to design and build an avalanche protection dam. KEYWORDS Avalanche protection ­ Modeling ­ Work Adresse de. SEGEL, M. SCHMITT, E. MICHEL VILLAZ, T. EME, S. ROUDNITSKA, M. NAAIM. Avalanche protection dam

  11. ABSTRACT: The Hetch Hetchy System provides San Francisco with most of its water supply. O'Shaughnessy Dam is one com-

    E-Print Network [OSTI]

    Pasternack, Gregory B.

    'Shaughnessy Dam is one com- ponent of this system, providing approximately 25 percent of water storage for the Hetch Hetchy System and none of its con- veyance. Removing O'Shaughnessy Dam has gained interest for restoring Hetch Hetchy Valley. The water supply feasibility of removing O'Shaughnessy Dam is analyzed

  12. BANDO DI PARTECIPAZIONE al PREMIO TESI "ADRIANA CAVA" Adriana Cava Jazz Ballet in collaborazione con il DAMS di Torino, in occasione del

    E-Print Network [OSTI]

    Di Pillo, Gianni

    con il DAMS di Torino, in occasione del trentennale di attività della coreografa Adriana Cava (docente di Storia della danza e del mimo del DAMS di Torino), valuterà le tesi di laurea di argomento vincitore, avvisato nella stessa data 8 aprile tramite mail e segnalato sui siti ufficiali del DAMS di

  13. On Flame-Wall Thermal-Coupling in Micro Combustors Yong Fan, Yuji Suzuki, and Nobuhide Kasagi

    E-Print Network [OSTI]

    Kasagi, Nobuhide

    On Flame-Wall Thermal-Coupling in Micro Combustors Yong Fan, Yuji Suzuki, and Nobuhide Kasagi Department of Mechanical Engineering, The University of Tokyo, Japan Keywords: Micro combustor, Premixed of premixed CH4/Air flame propagation and quenching in three quartz combustors with chamber depth of 0.7 mm, 1

  14. Oscillating Flame in Wall Temperature-Controlled Ultra-Thin Quartz Channels Yong FAN, Yuji SUZUKI and Nobuhide Kasagi

    E-Print Network [OSTI]

    Kasagi, Nobuhide

    associated with combustion in micro combustors lead to the finding that wall thermal and chemical conditions shows that the flame is quenched by wall heat loss. Key Words: Micro combustor, Oscillating flame, Phase of intense investigations on micro combustors. On the other hand, studies on new phenomena and physics

  15. Mapping of soot particles in a weakly sooting diffusion flame by aerosol techniques

    SciTech Connect (OSTI)

    Hepp, H.; Siegmann, K. [Federal Inst. of Tech., Zuerich (Switzerland). Lab. for Solid State Physics] [Federal Inst. of Tech., Zuerich (Switzerland). Lab. for Solid State Physics

    1998-10-01T23:59:59.000Z

    The evolution of detailed particle size distributions has been measured along the centerline of an axisymmetric diffusion flame of CH{sub 4} + Ar burning in air at 1 atm. Soot particles with mean diameters of 3--18 nm were observed. Changes in the size distribution exhibited zones where either nucleation, coagulation, or destruction of soot particles dominated. These highly sensitive measurements were made by microprobe sampling with an immediate dilution of 1:400, to quench the aerosol, and by subsequent application of aerosol measurement techniques. In parallel, the yield of photoemitted electrons from size-selected particles was determined. The yield shows a characteristic dependence on location in the flame, indicating changes of the particle`s surface. Multiphoton, time-of-flight mass spectrometry was used to investigate the correlation between polycyclic aromatic hydrocarbons in the flame and enhanced photoemission yield from the soot particles.

  16. Kilohertz PIV/PLMS of low-gravity turbulent flames in a drop tower I.G. Boxx, C.A. Idicheria, N.T. Clemens(1)

    E-Print Network [OSTI]

    Clemens, Noel T.

    -flame in a crossflow (JFICF). The system developed represents a major advance in the state of the art of microgravity to examine a hydrogen jet-flame in a crossflow (momentum flux ratio of 7, Re = 900) under normal and low. INTRODUCTION The turbulent jet-flame in a crossflow (JFICF) is a flowfield of theoretical and applied

  17. Compliance Monitoring of Yearling and Subyearling Chinook Salmon and Juvenile Steelhead Survival and Passage at John Day Dam, 2012

    SciTech Connect (OSTI)

    Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Weiland, Mark A.; Woodley, Christa M.; Hughes, James S.; Ploskey, Gene R.; Deng, Zhiqun; Carlson, Thomas J.

    2013-05-01T23:59:59.000Z

    The purpose of this compliance study was to estimate dam passage survival of yearling and subyearling Chinook salmon and steelhead smolts at John Day Dam during the spring and summer outmigrations in 2012. Under the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp), dam passage survival should be greater than or equal to 0.96 for spring migrants and greater than or equal to 0.93 for summer migrants, estimated with a standard error (SE) less than or equal to 0.015. The study also estimated smolt passage survival from the forebay 2 km upstream of the dam to the tailrace 3 km downstream of the dam, as well as the forebay residence time, tailrace egress time, spill passage efficiency (SPE), and fish passage efficiency (FPE), as required in the Columbia Basin Fish Accords (Fish Accords). A virtual/paired-release design was used to estimate dam passage survival at John Day Dam. The approach included releases of smolts, tagged with acoustic micro-transmitters, above John Day Dam that contributed to the formation of a virtual release at the face of John Day Dam. A survival estimate from this release was adjusted by a paired release below John Day Dam. A total of 3376 yearling Chinook salmon, 5726 subyearling Chinook salmon, and 3239 steelhead smolts were used in the virtual releases. Sample sizes for the below-dam paired releases (R2 and R3, respectively) were 997 and 995 for yearling Chinook salmon smolts, 986 and 983 for subyearling Chinook salmon smolts, and 1000 and 1000 for steelhead smolts. The Juvenile Salmon Acoustic Telemetry System (JSATS) tags were manufactured by Advanced Telemetry Systems. Model SS300 tags, weighing 0.304 g in air, were surgically implanted in yearling and subyearling Chinook salmon, and Model SS130 tag, weighing 0.438 g in air, were surgically implanted in juvenile steelhead for this investigation. The intent of the spring study was to estimate dam passage survival during both 30% and 40% spill conditions. The two spill conditions were to be systematically performed in alternating 2-day test intervals over the course of the spring outmigration. High flow conditions in 2012 interrupted the spill study. Dam passage survival was therefore estimated season-wide regardless of spill conditions.

  18. Enhancement of a laminar premixed methane/oxygen/nitrogen flame speed using femtosecond-laser-induced plasma

    SciTech Connect (OSTI)

    Yu Xin; Peng Jiangbo; Yi Yachao; Zhao Yongpeng; Chen Deying; Yu Junhua [National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Harbin 150080 (China); Institute of Opto-electronics, Harbin Institute of Technology, Harbin 150080 (China); Yang Peng; Sun Rui [Institute of Combustion Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2010-07-05T23:59:59.000Z

    We first investigate the effects of femtosecond-laser-induced plasma on the flame speed of a laminar premixed methane/oxygen/nitrogen flame with a wide range of the equivalence ratios (0.8-1.05) at atmospheric pressure. It is experimentally found that the flame speed increases 20.5% at equivalence ratios 1.05. The self-emission spectra from the flame and the plasma are studied and an efficient production of active radicals under the action of femtosecond (fs)-laser pulses has been observed. Based on the experimental data obtained, the presence of oxygen atom and hydrocarbon radicals is suggested to be a key factor enhancing flame speed.

  19. Soot formation and temperature structure in small methane-oxygen diffusion flames at subcritical and supercritical pressures

    SciTech Connect (OSTI)

    Joo, Hyun I.; Guelder, Oemer L. [University of Toronto, Institute for Aerospace Studies, 4925 Dufferin Street, Toronto, Ont. (Canada)

    2010-06-15T23:59:59.000Z

    An experimental study was conducted to examine the characteristics of laminar methane-oxygen diffusion flames up to 100 atmospheres. The influence of pressure on soot formation and on the structure of the temperature field was investigated over the pressure range of 10-90 atmospheres in a high-pressure combustion chamber using a non-intrusive, line-of-sight spectral soot emission diagnostic technique. Two distinct zones characterized the appearance of a methane and pure oxygen diffusion flame: an inner luminous zone similar to the methane-air diffusion flames, and an outer diffusion flame zone which is mostly blue. The flame height, marked by the visible soot radiation emission, was reduced by over 50% over the pressure range of 10-100 atmospheres. Between 10 and 40 atmospheres, the soot levels increased with increasing pressure; however, above 40 atmospheres the soot concentrations decreased with increasing pressure. (author)

  20. Mitigation of thermoacoustic instability utilizing steady air injection near the flame anchoring zone

    SciTech Connect (OSTI)

    Murat Altay, H.; Hudgins, Duane E.; Speth, Raymond L.; Annaswamy, Anuradha M.; Ghoniem, Ahmed F. [Massachusetts Institute of Technology, Department of Mechanical Engineering, Cambridge, MA 02139 (United States)

    2010-04-15T23:59:59.000Z

    The objective of this work is to investigate the effectiveness of steady air injection near the flame anchoring zone in suppressing thermoacoustic instabilities driven by flame-vortex interaction mechanism. We perform a systematic experimental study which involves using two different configurations of air injection in an atmospheric pressure backward-facing step combustor. The first configuration utilizes a row of micro-diameter holes allowing for air injection in the cross-stream direction just upstream of the step. The second configuration utilizes an array of micro-diameter holes located on the face of the step, allowing for air injection in the streamwise direction. The effects of each of these configurations are analyzed to determine which one is more effective in suppressing thermoacoustic instabilities at different operating conditions. The tests are conducted while varying the equivalence ratio and the inlet temperature. The secondary air temperature is always the same as the inlet temperature. We used pure propane or propane/hydrogen mixtures as fuels. Combustion dynamics are explored through simultaneous pressure and heat release-rate measurements, and high-speed video images. When the equivalence ratio of the reactant mixture is high, it causes the flame to flashback towards the inlet channel. When air is injected in the cross-stream direction, the flame anchors slightly upstream of the step, which suppresses the instability. When air is injected in the streamwise direction near the edge of step, thermoacoustic instability could be eliminated at an optimum secondary air flow rate, which depends on the operating conditions. When effective, the streamwise air injection prevents the shedding of an unsteady vortex, thus eliminating the flame-vortex interaction mechanism and resulting in a compact, stable flame to form near the step. (author)