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Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Energy consumption for baking and characteristics of baked product in relation to type of oven and baking procedure  

Science Conference Proceedings (OSTI)

Data were obtained and analyzed on 1) energy consumption when a test food was baked with four types of electric ovens (electric range oven, table model conventional oven, table model forced convection oven, and table model broiler/toaster oven) with three cooking procedures (participant's own procedure, preheated procedure, and cold start procedure); 2) patterns of energy consumption in 10-minute intervals; and 3) the characteristics of the finished food. Twenty participants from households in Columbus, Ohio, baked loaves of quick bread in a laboratory in the four types of ovens with three cooking procedures. Statistical analyses of data included analyses of variance, Tukey test, and Duncan's multiple range test. Significantly more energy was used with the participants' own procedures than with either the preheated or the cold start procedure (p < .01). There was no consistency in total energy consumption between the preheated and the cold start procedures in the four types of ovens. The electric range oven consumed significantly more energy than the other three types of ovens in the first 10-minute interval; however, the table model forced convection oven consumed significantly more energy than other ovens in the second and third 10-minute intervals. No consistent patterns were observed for volume and weight loss of breads baked with the three cooking procedures, but use of the table model forced convection oven always resulted in larger volume than with other ovens.

Nee, Y.

1982-01-01T23:59:59.000Z

2

Solar oven  

Science Conference Proceedings (OSTI)

A portable, foldable solar oven is provided wherein the basic construction material is ordinary cardboard, some surfaces of which are coated with a reflective material. The portable oven doubles as an insulated container for keeping refrigerated foodstuffs cold while being transported to a distant site for cooking.

Golder, J.C.

1981-10-06T23:59:59.000Z

3

Solar oven  

SciTech Connect

This patent describes a solar oven. It comprises: an oven chamber having an open end and defining an interior cooking chamber; means providing a flat-back interior surface on the cooking chamber for absorbing sunlight and converting the absorbed sunlight into heat; an oven door hingedly mounted over the open end and movable between open and closed positions relative to the open end; means for pivotably supporting the oven chamber about a first substantially horizontal pivot axis; user-actuable latch means for selectively retaining the oven chamber in selected positions around the first horizontal axis, the user-actuable latch means including a user releasable ratchet mechanism including a plurality of ratchet teeth formed on the oven chamber and ratchet pawl pivoted to the support means in a position to engage selective ones of the ratchet teeth to retain the over chamber in selected orientations around the horizontal axis, the latch means further including means for pivoting the pawl into and out of the path of movement of the ratchet teeth to thereby achieve the selective positioning; a tray disposed within the interior cooking chamber for supporting foodstuffs during coking; pivot means for pivotally mounting the tray within the interior cooking chamber for movement around a second substantially horizontal pivot axis such that the tray can be positioned so as to maintain the foodstuffs in a substantially level position independently of the position of the oven chamber around the first pivot axis.

Burns, T.J.; Burns, C.L.

1989-07-18T23:59:59.000Z

4

Oven | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Oven Oven Addthis Description Saving energy saves you money. Buy energy-saving light bulbs. (Ad Council PSA) Duration 0:33 Topic Energy Efficiency Heating & Cooling Home...

5

Solar oven  

Science Conference Proceedings (OSTI)

This paper describes a solar oven. It includes in combination: a rectangular cooking pan with a bottom and four side walls, open at the upper end, an exterior casing having a bottom and four side walls and having an outer coating to lower the heat absorption, a body of insulation in between the cooking pan and the exterior casing, the top edge of the insulation, casing, and cooking pan all being coplanar to provide a rectangular shelf, a glass-supporting frame enclosing and protecting a sheet of low-iron, heat-conductive glass, the glass having an iron content of only about 0.04% and a transmittance of heat about 83%, a mirror-supporting frame having a solid top portion and top sheet for supporting a mirror combination below the sheet, hinges connecting the mirror supporting frame to the casing, a support arm pivoted to the side of the glass frame and having a series of openings therethrough, and a mirror-support projection secured to the mirror-supporting frame for engaging one of the openings through the support arm for enabling the mirror to be supported at any of a plurality of positions at various angles relative to the shelf and the glass sheet. The glass and its glass-supporting frame being unattached to the cooking pan, casing, and body for free manipulation by hand.

Ghatak, R.N.

1989-07-25T23:59:59.000Z

6

The Skill of ECMWF Medium-Range Forecasts during the Year of Tropical Convection 2008  

Science Conference Proceedings (OSTI)

This study uses the European Centre for Medium-Range Weather Forecasts (ECMWF) model-generated high-resolution 10-day-long predictions for the Year of Tropical Convection (YOTC) 2008. Precipitation forecast skills of the model over the tropics ...

Arindam Chakraborty

2010-10-01T23:59:59.000Z

7

Short-Range (0–48 h) Numerical Prediction of Convective Occurrence, Mode, and Location  

Science Conference Proceedings (OSTI)

A verification of high-resolution (6-km grid spacing) short-range (0–48 h) numerical model forecasts of warm-season convective occurrence, mode, and location was conducted over the Lake Michigan region. All available days from 5 April through 20 ...

Michael A. Fowle; Paul J. Roebber

2003-10-01T23:59:59.000Z

8

Lesson 9 - Solar Ovens  

NLE Websites -- All DOE Office Websites (Extended Search)

Lesson 9 - Solar Ovens Colorado Academic Standards: Standard 3: Earth Systems Science Kindergarten: Concepts and skills students master: 1. The Sun provides heat and light to...

9

Technical support document: Energy efficiency standards for consumer products: Room air conditioners, water heaters, direct heating equipment, mobile home furnaces, kitchen ranges and ovens, pool heaters, fluorescent lamp ballasts and television sets. Volume 1, Methodology  

SciTech Connect

The Energy Policy and Conservation Act (P.L. 94-163), as amended, establishes energy conservation standards for 12 of the 13 types of consumer products specifically covered by the Act. The legislation requires the Department of Energy (DOE) to consider new or amended standards for these and other types of products at specified times. DOE is currently considering amending standards for seven types of products: water heaters, direct heating equipment, mobile home furnaces, pool heaters, room air conditioners, kitchen ranges and ovens (including microwave ovens), and fluorescent light ballasts and is considering establishing standards for television sets. This Technical Support Document presents the methodology, data, and results from the analysis of the energy and economic impacts of the proposed standards. This volume presents a general description of the analytic approach, including the structure of the major models.

Not Available

1993-11-01T23:59:59.000Z

10

Portable oven air circulator  

DOE Patents (OSTI)

A portable air circulating apparatus for use in cooking ovens which is used to create air currents in the oven which transfer heat to cooking foodstuffs to promote more rapid and more uniform cooking or baking, the apparatus including a motor, fan blade and housing of metallic materials selected from a class of heat resistant materials.

Jorgensen, Jorgen A. (Bloomington, MN); Nygren, Donald W. (Minneapolis, MN)

1983-01-01T23:59:59.000Z

11

A modified concentrating type solar oven for outdoor cooking  

Science Conference Proceedings (OSTI)

Solar cookers offer a partial solution to many problems for the poor developing areas of the world. In these regions energy used for cooking sometimes comprises four fifths of the total energy demand. Solar cookers are generally four catagories: direct focusing, oven, ovenfocusing and indirect types. The direct focusing types failed to boil water under windy conditions due to excessive convection losses from the bare cooking pot placed at the concentrator focus. The oven type cookers, such as Telkes oven, observe the rules of energy conservation and thus are more efficient and less affected by windy weather. However, this oven suffers from two major problems. First, tilting the oven could cause food spillage unless a hinged support is used for the pot. This adds complication to the design of Telkes oven. Second, the solar radiation is added to the pot from the top for high solar altitude angles. This leads to poor heat transfer to the food inside the pot. The advantages of concentrating and oven cookers can be obtained by widding of a point focus concentrator to a new oven type receiver. In this paper the concept and design details of such an oven are introduced. Theoretical and experimental analyses of the developed cooker are given.

Khalifa, A.M.A.

1983-12-01T23:59:59.000Z

12

Flat plate solar oven  

Science Conference Proceedings (OSTI)

The construction of an Indian Rs. 186 (US $20.33) flat-plate solar oven is described. Detailed drawings are provided and relevant information on cooking times and temperature for different foods is given.

Parikh, M.

1981-01-01T23:59:59.000Z

13

Demountable solar oven  

Science Conference Proceedings (OSTI)

A demountable solar oven includes a principal base upon which is mounted a secondary supporting base collar which contains the essential operating parts and which supports two removable arms at their base whose upper end form diametrically opposed pivots for receiving the appropriately disposed pivots of the cooking chamber. The food basket provided with similarly diametrically opposed pivots is disposed interiorly of the cooking chamber and by virtue of a weight disposed at the bottom thereof the wire basket always maintains a horizontal position irrespective of the angle of the oven itself. A transparent hemispherical cover including a shadow box indicator is disposed over the oven in the direction of the sun and a series of individual plate reflectors are hinged together by means of pins, a certain number of which pins are utilized to attach the reflectors to the oven rim. Adjustable feet are disposed at the bottom of the supporting base for adjusting the vertical position of the oven and a level indicator as well as rotationally directional indicators are provided for determining the position of the oven as desired. The disassembled parts occupy a minimum space and various of the parts can be disposed together for the disassembled unit to occupy a very small space.

Erwin, S.F.

1983-04-05T23:59:59.000Z

14

Spiral track oven  

Science Conference Proceedings (OSTI)

Final report on development of a continuously operating oven system in which the parts are progressing automatically on a spiral track for in-line service installation for the production of electronic and/or other components to be heat cured or dried.

Drobilisch, Sandor

1998-12-20T23:59:59.000Z

15

Progressive Powder Coating: New Infrared Curing Oven at Metal Finishing Plant Increases Production by 50%  

SciTech Connect

Progressive Powder Coating in Mentor, Ohio, is a metal finishing plant that uses a convection oven in its manufacturing process. In an effort to save energy and improve production, the company installed an infrared oven in between the powder coating booth and the convection oven on its production line. This installation allowed the plant to increase its conveyor line speed and increase production by 50 percent. In addition, the plant reduced its natural gas consumption, yielding annual energy savings of approximately$54,000. With a total project cost of$136,000, the simple payback is 2.5 years.

Not Available

2003-05-01T23:59:59.000Z

16

Bake Oven Design and Improvement  

Science Conference Proceedings (OSTI)

Mar 13, 2012 ... Electrode Technology for Aluminium Production: Bake Oven Design and ... from shaft calciners is recovered for heating coal tar pitch and power ...

17

Oven wall panel construction  

DOE Patents (OSTI)

An oven roof or wall is formed from modular panels, each of which comprises an inner fabric and an outer fabric. Each such fabric is formed with an angle iron framework and somewhat resilient tie-bars or welded at their ends to flanges of the angle irons to maintain the inner and outer frameworks in spaced disposition while minimizing heat transfer by conduction and permitting some degree of relative movement on expansion and contraction of the module components. Suitable thermal insulation is provided within the module. Panels or skins are secured to the fabric frameworks and each such skin is secured to a framework and projects laterally so as slidingly to overlie the adjacent frame member of an adjacent panel in turn to permit relative movement during expansion and contraction.

Ellison, Kenneth (20 Avondale Cres., Markham, CA); Whike, Alan S. (R.R. #1, Caledon East, both of Ontario, CA)

1980-04-22T23:59:59.000Z

18

Range dependent errors in the convective and stratiform partitioning of a radar precipitation estimation algorithm  

E-Print Network (OSTI)

The Tropical Rainfall Measuring Mission (TRMM), designed to assist climate and atmospheric circulation modeling efforts by providing accurate information on tropical precipitation and latent-heat release, will require ground based validation of satellite derived rainfall totals and type classification. A key element in ground validation is the precipitation classification method authored by Steiner and Houze. The method partitions precipitation by type using a radar reflectivity threshold technique. Steiner and Houze report a lack of any significant range dependency, despite the normal problems associated with beam spreading and increasing altitude with range. This study will examine the Steiner and Houze classification method to quantify the effect of range dependent problems in discerning precipitation type. Radar data for this study were collected on January 10 and 18, 1993 during the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean-Atmosphere Response Experiment (COARE), by the National Oceanic and Atmospheric Administration (NOAA) N42RF WP-3D Orion aircraft's tail Doppler radar as well as the Massachusetts Institute of Technology's (MIT) Doppler radar deployed on board the United States research vessel Vickers. The data were chosen so the PW-3D tail radar data set maintained low ranges to precipitation of interest while the MIT radar data set possessed a wide variation of range. Possible error sources such as position error, radar calibration error, and temporal data collection differences, were minimized so that range dependency could be focused on. Range dependent beam spreading influenced precipitation classification over the largest span of ranges, and the greatest portion of the data. Also, beam spreading was found to increase the horizontal extent of precipitation areas in a direction perpendicular to the central axis of the radar beam. Overall, using the Steiner and Houze classification method, 24.0% and 21.6% of the precipitation with reflectivity greater than 15 dBZ was classified differently by the two radar data sets at the 1.5 km and 3.0 km analysis levels respectively. The percentage of total rainfall from all precipitation classified differently was 26% for the 1.5 km analysis level, and 28% for the 3.0 km level.

Wood, David Richard

1996-01-01T23:59:59.000Z

19

Solar Oven, Take One: FAIL | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Oven, Take One: FAIL Solar Oven, Take One: FAIL June 22, 2011 - 11:45am Addthis Our homemade solar oven. | Courtesy of: Moon Choe Our homemade solar oven. | Courtesy of: Moon Choe...

20

One temperature model for effective ovens  

E-Print Network (OSTI)

Most of the thermodynamic analysis of ovens are focused on efficiency, but they need to behaves under real-life conditions, then the effectiveness of the ovens plays a crucial role in their design. In this paper we present a thermodynamical model able to describe the temperature evolution in ovens, furnaces or kilns to harden, burn or dry different products and which provides a methodology to design these heating devices. We use the required temperature evolution for each product and process as main ingredient in the methodology and procedure to design ovens and we place in the right role the efficiency criteria. We use global energy balance equation for the oven under transient situation as the thermodynamic starting point for developing the model. Our approach is able to consider different configurations for these heating devices, or recirculating or open situations, etc.

Tapia, Saul

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

New Energy Efficiency Standards for Microwave Ovens to Save Consumers...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

New Energy Efficiency Standards for Microwave Ovens to Save Consumers on Energy Bills New Energy Efficiency Standards for Microwave Ovens to Save Consumers on Energy Bills May 31,...

22

EETD Assists in Analysis of Microwave Oven Energy Efficiency...  

NLE Websites -- All DOE Office Websites (Extended Search)

EETD Assists in Analysis of Microwave Oven Energy Efficiency Standard June 2013 The Department of Energy recently announced new energy efficiency standards for microwave ovens....

23

Method for processing coke oven gas  

SciTech Connect

Coke oven gas is subjected, immediately after the discharge thereof from coke ovens, and without any preliminary cooling operation or any purification operation other than desulfurization, to a catalytic cracking operation to form a hot cracked gas which is rich in hydrogen and carbon monoxide. The catalytic cracking reaction is carried out in the presence of a hydrogen-containing and/or CO2-containing gas, with a steam reforming catalyst.

Flockenhaus, C.; Meckel, J.F.; Wagener, D.

1980-11-25T23:59:59.000Z

24

Theoretical Modeling Approach for a Common Residential Electrically Heated Oven and Proposed Oven Design Modification.  

E-Print Network (OSTI)

??Current research has developed a fully predictive model of an electrically heated common residential oven. This system was modeled using a fully explicit approach and,… (more)

Breen, Mark Allan

2004-01-01T23:59:59.000Z

25

Orographic Modification of Convection and Flow Kinematics by the Oregon Coast Range and Cascades during IMPROVE-2  

Science Conference Proceedings (OSTI)

This paper describes the kinematic and precipitation evolution accompanying the passage of a cold baroclinic trough over the Central Oregon Coast Range and Cascades during 4–5 December 2001 of the second Improvement of Microphysical ...

Brian A. Colle; Yanluan Lin; Socorro Medina; Bradley F. Smull

2008-10-01T23:59:59.000Z

26

Process Parameters and Energy Use of Gas and Electric Ovens in Industrial Applications  

E-Print Network (OSTI)

The study was conducted to evaluate the energy use of natural gas and electric ovens in the production of polymer bearings and components. Tests were conducted to evaluate and compare the performance of natural gas and electric ovens in the process of sintering billets which are made from a broad range of materials such as PTFE and other fluoropolymers, elastomers, themosets, themoplastics and composites. The purpose of this study was to compare the process parameters under similar conditions for industrial applications where electric ovens have predominant use. Tests were performed to obtain the process efficiency and examine cost savings potential in converting electric ovens to natural gas. Preliminary results show that, for the plat studied, cost savings of about $10,000 per oven can be achieved, with a simple payback period of less than two years. The results also show that additional energy savings will be realized if the oven size and exhaust flow are carefully selected. The data obtained from these experiments were used to calculate process efficiency. Design features and environmental issues are discussed.

Kosanovic, D.; Ambs, L.

2000-04-01T23:59:59.000Z

27

The FlashBake oven: Lightwave oven delivers high-quality, quick cooking  

SciTech Connect

The FlashBake oven is a well-publicized new electrotechnology that over 40 utilities are promoting for commercial food service applications, but is it worth its high price? E Source research shows that this $5,000 to $8,500 lightwave oven can increase sales and profitability in a number of applications, thus paying for itself within months to a year or two. The FlashBake does so by cooking foods less than two inches thick in two minutes or less, as quickly as microwave ovens do, but with quality equal to or greater than that of conventional gas and electric ovens. The FlashBake makes sense for restaurants and kiosks that offer quick-order menus, as well as for full-menu restaurants that can use the FlashBake during slow periods (instead of larger ovens) and during busy periods (for extra capacity). In these target market applications, the FlashBake is likely to use less energy due to its extremely low idle energy use. It is not well suited to banquet and institutional kitchens that require large numbers of the same item to be cooked and ready simultaneously. The FlashBake has only one tray, so cooking large volumes may take longer, require more labor, and use more energy than a conventional oven that has multiple cooking racks. Energy use is rarely a major concern of those who buy FlashBake ovens, since energy for cooking represents a small fraction of a restaurant`s overall operating costs. The main selling point of the FlashBake is menu and productivity enhancement.

Gregerson, J.

1995-06-01T23:59:59.000Z

28

Open Ended Microwave Oven for Packaging  

E-Print Network (OSTI)

A novel open waveguide cavity resonator is presented for the combined variable frequency microwave curing of bumps, underfills and encapsulants, as well as the alignment of devices for fast flip-chip assembly, direct chip attach (DCA) or wafer-scale level packaging (WSLP). This technology achieves radio frequency (RF) curing of adhesives used in microelectronics, optoelectronics and medical devices with potential simultaneous micron-scale alignment accuracy and bonding of devices. In principle, the open oven cavity can be fitted directly onto a flip-chip or wafer scale bonder and, as such, will allow for the bonding of devices through localised heating thus reducing the risk to thermally sensitive devices. Variable frequency microwave (VFM) heating and curing of an idealised polymer load is numerically simulated using a multi-physics approach. Electro-magnetic fields within a novel open ended microwave oven developed for use in micro-electronics manufacturing applications are solved using a de icated Yee sche...

Sinclair, K I; Desmulliez, M Y P; Goussetis, G; Bailey, C; Parrott, K; Sangster, A J

2008-01-01T23:59:59.000Z

29

Multiple delivery cesium oven system for negative ion sources  

Science Conference Proceedings (OSTI)

Distribution of cesium in large negative ion beam sources to be operational in ITER, is presently based on the use of three or more cesium ovens, which operate simultaneously and are controlled remotely. However, use of multiple Cs ovens simultaneously is likely to pose difficulties in operation and maintenance of the ovens. An alternate method of Cs delivery, based on a single oven distribution system is proposed as one which could reduce the need of simultaneous operation of many ovens. A proof of principle experiment verifying the concept of a multinozzle distributor based Cs oven has been carried out at Institute for Plasma Research. It is also observed that the Cs flux is not controlled by Cs reservoir temperature after few hours of operation but by the temperature of the distributor which starts behaving as a Cs reservoir.

Bansal, G.; Bhartiya, S.; Pandya, K.; Bandyopadhyay, M.; Singh, M. J.; Soni, J.; Gahlaut, A.; Parmar, K. G.; Chakraborty, A. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat 382428 (India)

2012-02-15T23:59:59.000Z

30

Solar Oven, Take One: FAIL | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Solar Oven, Take One: FAIL Solar Oven, Take One: FAIL Solar Oven, Take One: FAIL June 15, 2011 - 11:56am Addthis Our homemade solar oven. | Courtesy of Moon Choe Our homemade solar oven. | Courtesy of Moon Choe Moon Choe EERE Summer Intern The first time I ever saw solar cookers was on the news in the summer of 2009 (though that would make it their winter, as I was living in Chile at the time), as part of a development project in the north, which is mostly desert. I had no idea solar cookers were so markedly simple in all various facets, such as appearance, use, and construction, and ever since then, it always remained on my to-do list to make one of my own. Another added benefit that I was unaware of is that a solar cooker works at any time of year, so long as it's receiving direct sunlight (i.e. not

31

Solar Oven, Take One: FAIL | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Solar Oven, Take One: FAIL Solar Oven, Take One: FAIL Solar Oven, Take One: FAIL June 15, 2011 - 11:56am Addthis Our homemade solar oven. | Courtesy of Moon Choe Our homemade solar oven. | Courtesy of Moon Choe Moon Choe EERE Summer Intern The first time I ever saw solar cookers was on the news in the summer of 2009 (though that would make it their winter, as I was living in Chile at the time), as part of a development project in the north, which is mostly desert. I had no idea solar cookers were so markedly simple in all various facets, such as appearance, use, and construction, and ever since then, it always remained on my to-do list to make one of my own. Another added benefit that I was unaware of is that a solar cooker works at any time of year, so long as it's receiving direct sunlight (i.e. not

32

Problem of improving coke oven gas purification systems  

Science Conference Proceedings (OSTI)

A discussion of the problems of improving desulfurization processes of coke oven gas was presented. Of particular interest were control systems and increasing capacity of the coke ovens. Included in the discussion were the vacuum-carbonate and arsenic-soda sulfur removal systems. Problems involved with these systems were the number of treatment operations, the volume of the reagents used, and the operation of equipment for naphthalene and cyanide removal.

Goldin, I.A.

1982-01-01T23:59:59.000Z

33

Convection towers  

DOE Patents (OSTI)

Convection towers which are capable of cleaning the pollution from large quantities of air, of generating electricity, and of producing fresh water utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity, and condensers produce fresh water. 6 figs.

Prueitt, M.L.

1996-01-16T23:59:59.000Z

34

Convection towers  

DOE Patents (OSTI)

Convection towers which are capable of cleaning the pollution from large quantities of air, of generating electricity, and of producing fresh water utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity, and condensers produce fresh water.

Prueitt, Melvin L. (Los Alamos, NM)

1996-01-01T23:59:59.000Z

35

Convection towers  

DOE Patents (OSTI)

Convection towers which are capable of cleaning the pollution from large quantities of air, of generating electricity, and of producing fresh water utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity, and condensers produce fresh water.

Prueitt, Melvin L. (Los Alamos, NM)

1995-01-01T23:59:59.000Z

36

Convection towers  

DOE Patents (OSTI)

Convection towers which are capable of cleaning the pollution from large quantities of air and of generating electricity utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity. Other embodiments may also provide fresh water, and operate in an updraft mode.

Prueitt, Melvin L. (Los Alamos, NM)

1994-01-01T23:59:59.000Z

37

Innovative coke oven gas cleaning system for retrofit applications  

DOE Green Energy (OSTI)

The coke plant at the Sparrows Point Plant consist of three coke oven batteries and two coal chemical plants. The by-product coke oven gas (COG) consists primarily of hydrogen, methane, carbon monoxide, nitrogen and contaminants consisting of tars, light oils (benzene, toluene, and xylene) hydrogen sulfide, ammonia, water vapor and other hydrocarbons. This raw coke oven gas needs to be cleaned of most of its contaminants before it can be used as a fuel at other operations at the Sparrows Point Plant. In response to environmental concerns, BSC decided to replace much of the existing coke oven gas treatment facilities in the two coal chemical Plants (A and B) with a group of technologies consisting of: Secondary Cooling of the Coke oven Gas; Hydrogen Sulfide Removal; Ammonia Removal; Deacification of Acid Gases Removed; Ammonia Distillation and Destruction; and, Sulfur Recovery. This combination of technologies will replace the existing ammonia removal system, the final coolers, hydrogen sulfide removal system and the sulfur recovery system. The existing wastewater treatment, tar recovery and one of the three light oil recovery systems will continue to be used to support the new innovative combination of COG treatment technologies.

Not Available

1992-08-24T23:59:59.000Z

38

A container for heat treating materials in microwave ovens  

DOE Patents (OSTI)

The efficiency of a microwave oven of a conventional two-source configuration and energy level is increased by providing the oven with a container for housing a refractory material to be treated. The container is formed to top and bottom walls transparent to microwaves while the sidewalls, in a circular configuration, are formed of a nonmetallic material opaque to microwave radiation for reflecting the radiation penetrating the top and bottom walls radially inwardly into the center of the container wherein a casket of heat-insulating material is provided for housing the material to be heat treated. The reflection of the microwave radiation from the sidewalls increases the concentration of the microwaves upon the material being heat treated while the concentration of the microwaves upon the material being heat treated while the casket retains the heat to permit the heating of the material to a substantially higher temperature than achievable in the oven without the container.

Holcombe, C.E.; Dykes, N.L.; Kimrey, H.D. Jr.; Mills, J.E.

1988-01-26T23:59:59.000Z

39

Container for heat treating materials in microwave ovens  

DOE Patents (OSTI)

The efficiency of a microwave oven of a conventional two-source configuration and energy level is increased by providing the oven with a container for housing a refractory material to be treated. The container is formed of top and bottom walls transparent to microwaves while the sidewalls, in a circular configuration, are formed of a nonmetallic material opaque to microwave radiation reflecting the radiation penetrating the top and bottom walls radially inwardly into the center of the container wherein a casket of heat-insulating material is provided for housing the material to be heat treated. The reflection of the microwave radiation from the sidewalls increases the concentration of the microwaves upon the material being heat treated while the casket retains the heat to permit the heating of the material to a substantially higher temperature than achieveable in the oven without the container.

Holcombe, Cressie E. (Farragut, TN); Dykes, Norman L. (Oak Ridge, TN); Kimrey, Jr., Harold D. (Knoxville, TN); Mills, James E. (Knoxville, TN)

1989-01-01T23:59:59.000Z

40

New process for coke-oven gas desulfurization  

SciTech Connect

With the EPA reclassifying spent iron oxide as a hazardous waste material in 1990, an alternative technology was sought for desulfurizing coke-oven gas. Vacasulf technology was adopted for reasons that included: producing of coke battery heating gas without further polishing and high-quality elemental sulfur; lowest operating cost in comparison with other methods; no waste products; and integrates with existing ammonia destruction facility. Vacasulf requires a single purchased material, potassium hydroxide, that reacts with carbon dioxide in coke-oven gas to form potassium carbonate which, in turn, absorbs hydrogen sulfide. Operation of the system has been successful following the resolution of relatively minor start-up problems.

Currey, J.H. [Citizens Gas and Coke Utility, Indianapolis, IN (United States)

1995-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Testing of the Burns-Milwaukee`s Sun Oven  

DOE Green Energy (OSTI)

A Burns-Milwaukee Sun Oven was tested at Sandia`s Solar Thermal Test Facility. It was instrumented with five type K thermocouples to determine warm-up rates when empty and when a pot containing two liters of water was placed inside. It reached inside air temperatures above 160{degrees}C (320{degrees}F). It heated two liters of water from room temperatures to 80{degrees}C, (175{degrees}F), in 75 minutes. Observations were also made on the cooling and reheating rates during a cloud passage. The adverse effects of wind on operation of the solar oven was also noted.

Moss, T.A.

1997-03-01T23:59:59.000Z

42

Convection towers  

DOE Patents (OSTI)

Convection towers which are capable of cleaning the pollution from large quantities of air and of generating electricity utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity. Other embodiments may also provide fresh water, and operate in an updraft mode. 5 figures.

Prueitt, M.L.

1994-02-08T23:59:59.000Z

43

Characterization of Momentum Transport Associated with Organized Moist Convection and Gravity Waves  

Science Conference Proceedings (OSTI)

Tropical convection is inherently multiscalar, involving complex fields of clouds and various regimes of convective organization ranging from small disorganized cumulus up to large organized convective clusters. In addition to being a crucial ...

Todd P. Lane; Mitchell W. Moncrieff

2010-10-01T23:59:59.000Z

44

Polymer Surface Modification Using Microwave-Oven-Generated Plasma  

E-Print Network (OSTI)

, diameter 160 mm) are from Fisher Scientific. Compressed oxygen and ethanol (100%) are from Air Products a Barnstead EASYpure UV unit. Plasma is generated with a 1100-W countertop microwave oven (Amana, ACM2160AB.Afterrinsing,thesamples are dried with compressed air and placed on a glass microscope slide. The slide is then positioned

Steinbock, Oliver

45

CONVECTION REACTOR  

DOE Patents (OSTI)

An homogeneous nuclear power reactor utilizing convection circulation of the liquid fuel is proposed. The reactor has an internal heat exchanger looated in the same pressure vessel as the critical assembly, thereby eliminating necessity for handling the hot liquid fuel outside the reactor pressure vessel during normal operation. The liquid fuel used in this reactor eliminates the necessity for extensive radiolytic gas rocombination apparatus, and the reactor is resiliently pressurized and, without any movable mechanical apparatus, automatically regulates itself to the condition of criticality during moderate variations in temperature snd pressure and shuts itself down as the pressure exceeds a predetermined safe operating value.

Hammond, R.P.; King, L.D.P.

1960-03-22T23:59:59.000Z

46

New packing in absorption systems for trapping benzene from coke-oven gas  

SciTech Connect

The efficiency of benzene removal from coke-oven gas in absorption units OAO Alchevskkoks with new packing is assessed.

V.V. Grabko; V.M. Li; T.A. Shevchenko; M.A. Solov'ev [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

2009-07-15T23:59:59.000Z

47

Convective heater  

DOE Patents (OSTI)

A convective heater for heating fluids such as a coal slurry is constructed of a tube circuit arrangement which obtains an optimum temperature distribution to give a relatively constant slurry film temperature. The heater is constructed to divide the heating gas flow into two equal paths and the tube circuit for the slurry is arranged to provide a mixed flow configuration whereby the slurry passes through the two heating gas paths in successive co-current, counter-current and co-current flow relative to the heating gas flow. This arrangement permits the utilization of minimum surface area for a given maximum film temperature of the slurry consistent with the prevention of coke formation. 14 figs.

Thorogood, R.M.

1983-12-27T23:59:59.000Z

48

Convective heater  

DOE Patents (OSTI)

A convective heater for heating fluids such as a coal slurry is constructed of a tube circuit arrangement which obtains an optimum temperature distribution to give a relatively constant slurry film temperature. The heater is constructed to divide the heating gas flow into two equal paths and the tube circuit for the slurry is arranged to provide a mixed flow configuration whereby the slurry passes through the two heating gas paths in successive co-current, counter-current and co-current flow relative to the heating gas flow. This arrangement permits the utilization of minimum surface area for a given maximum film temperature of the slurry consistent with the prevention of coke formation.

Thorogood, Robert M. (Macungie, PA)

1986-01-01T23:59:59.000Z

49

Convective heater  

DOE Patents (OSTI)

A convective heater for heating fluids such as a coal slurry is constructed of a tube circuit arrangement which obtains an optimum temperature distribution to give a relatively constant slurry film temperature. The heater is constructed to divide the heating gas flow into two equal paths and the tube circuit for the slurry is arranged to provide a mixed flow configuration whereby the slurry passes through the two heating gas paths in successive co-current, counter-current and co-current flow relative to the heating gas flow. This arrangement permits the utilization of minimum surface area for a given maximum film temperature of the slurry consistent with the prevention of coke formation.

Thorogood, Robert M. (Macungie, PA)

1983-01-01T23:59:59.000Z

50

Testing of the Burns-Milwaukee's Sun Oven  

E-Print Network (OSTI)

A Burns-Milwaukee Sun Oven was tested at Sandia's Solar Thermal Test Facility. It was instrumented with five type K thermocouples to determine warm-up rates when empty and when a pot containing two liters of water was placed inside. It reached inside air temperatures above 160 o C (320 o F). It heated two liters of water from room temperature to 80 o C, (175 o F), in 75 minutes. Observations were also made on the cooling and reheating rates during a cloud passage. The adverse effects of wind on operation of the solar oven was also noted. ii 1 The Solar Thermal Design Assistance Center (STDAC) at Sandia National Laboratories evaluated a Sun Oven from Burns-Milwaukee at Sandia's Solar Thermal Test Facility in Albuquerque NM. It was designed for single family household cooking. It is targeting developing countries' alternative energy markets where conventional fuels are not available and wood is the primary fuel used for cooking. Because of the wide variety and types of solar...

Moss Solar Thermal; T. A. Moss

1997-01-01T23:59:59.000Z

51

Observations and Modeling of Banded Orographic Convection  

Science Conference Proceedings (OSTI)

Radar images and numerical simulations of three shallow convective precipitation events over the Coastal Range in western Oregon are presented. In one of these events, unusually well-defined quasi-stationary banded formations produced large ...

Daniel J. Kirshbaum; Dale R. Durran

2005-05-01T23:59:59.000Z

52

Takahax-Hirohax process for coke oven gas desulfurization  

SciTech Connect

This paper describes the Takahax-Hirohax process to desulfurize coke oven gas and to produce an ammonium sulfate end product. A review is also made of current operating experience and recent technical developments. The Takahax-Hirohax process is extremely useful when the COG contains a suitable ammonia to sulfur ratio and when ammonium sulfate is a desirable end product. No contaminated effluent streams are emitted from the process. The process is simple, reliable, flexible, and responds easily to COG variations. 4 figures, 3 tables. (DP)

Gastwirth, H.; Miner, R.; Stengle, W.

1981-01-01T23:59:59.000Z

53

Testing of the Sunstove Organization`s Sunstove Solar Oven  

DOE Green Energy (OSTI)

A Sunstove Organization`s Sunstove was tested at Sandia`s Solar Thermal Test Facility. It was instrumented with five type K thermocouples to determine warm-up rates when empty and when a pot containing two liters of water was placed inside. It reached inside air temperatures above 115{degrees}C (240{degrees}F). It heated two liters of water from room temperature to 80{degrees}C (175{degrees}F) in about two hours. Observations were made on the cooling and reheating rates during a cloud passage. The adverse effects of wind on the operation of the solar oven were also noted.

Moss, T.A.

1997-03-01T23:59:59.000Z

54

Reducing Energy Consumption on Process Ovens & Oxidation Systems  

E-Print Network (OSTI)

With the uncertain cost of energy, optimizing the use of air in process dryers, ovens and air pollution control systems is critical to your bottom line. The revived emphasis on air management through the entire process, from plant make-up air heating systems to pollution control system exhaust, provides many opportunities to save energy and cut operating costs. This presentation includes an overview of good air management practices used to optimize energy use in your process and plant. One of the most important benefits of the more stringent air pollution control regulations throughout the world is the focus on better use and conservation of our natural resources. Through the efforts of many of the world's finest engineers and scientists the world is now realizing the benefits of an environmentally friendly approach to manufacturing. These benefits, which include more efficient process operation, less waste generation and reduced emissions, have produced the unforeseen benefit of reduced production costs and higher quality products. Process dryers and ovens are used in the manufacture of a wide variety of products produced by the companies represented at the Industrial Energy Technology Conference. This equipment is installed and operating in facilities that produce printed materials, packaging materials, adhesive tapes, pharmaceutical diagnostic materials, coated papers & films, foil laminations, electronic media, and photographic & x-ray films. They are also used extensively in the food industry. The products manufactured include baked goods, cereals, pet food, tobacco, and many other products. Ovens are used to bake and cure surface coated materials. Such as building siding, window frames, window blinds, automotive parts, wood products, and miscellaneous metal parts. More stringent environmental regulations are also impacting the design and operation of coating and food processes. Today air pollution control devices are used on many of the above applications to control the emissions of volatile organic compounds (VOC's) and odors. As emission limits have decreased, the use of permanent total enclosures PTE's are becoming a standard part of the process line design. These enclosures are used to obtain 100% capture of the solvents used in the process. In addition, concerns over solvent concentrations in ovens along with concerns over exposure limits to employees have combined to drive process exhaust flows ever higher. Increasing process exhaust flows has been the common approach to addressing process and environmental issues. This increase in exhaust flows has resulted in significant increases in energy use and operating costs.

Worachek, C.

2002-04-01T23:59:59.000Z

55

Severe Convective Wind Environments  

Science Conference Proceedings (OSTI)

Nontornadic thunderstorm winds from long-lived, widespread convective windstorms can have a tremendous impact on human lives and property. To examine environments that support damaging wind producing convection, sounding parameters from Rapid ...

Evan L. Kuchera; Matthew D. Parker

2006-08-01T23:59:59.000Z

56

Rapid determination of wood fuel moisture content using a microwave oven for drying  

SciTech Connect

A method of determining moisture content (MC) of wood fuel using a microwave oven for drying the wood was evaluated by drying paired samples of five different wood fuel types in a microwave oven and a conventional oven. When compared to the conventional oven drying method, the microwave technique produces consistently lower MC determinations, although the differences are less than 1 percent. The advantage of the microwave technique is the speed at which MC determinations can be determined (less than 15 minutes). Schedules for drying five wood fuel types are presented. (Refs. 7).

Harris, R.A.

1982-10-01T23:59:59.000Z

57

Conjunctive management of groundwater and surface water resources in the Upper Ovens River Valley.  

E-Print Network (OSTI)

??Regression analysis produced equations for relating Ovens River levels to groundwater levels with a high correlation. These equations can relate stream flow objectives to corresponding… (more)

Lovell, Daniel Martin

2009-01-01T23:59:59.000Z

58

Desulphurization of coke oven gas by the Stretford Process  

SciTech Connect

The Stretford process is probably the most effective means available for removing hydrogen sulphide from gas streams. For streams which do not contain hydrogen cyanide or excessive oxygen it should be nearly ideal. However, the large volume of waste liquor generated by fixation of hydrogen cyanide has prevented its widespread adoption for coke oven gas treatment. Investigations of various proposals for treating the waste liquor indicate that the only practicable way of dealing with it is by reductive incineration. Although attempts to apply the Peabody-Holmes reductive incineration process have been disappointing, significant progress in overcoming some of its deficiencies has been made. The Zimpro wet oxidation process will provide a convenient method of treating the HCN scrubber effluent at No. 1 Plant. However, it will not treat the sodium based liquor from the Stretford plant. Its application to Stretford waste treatment is limited to situations where ammonium liquors and ammonium sulphate recovery facilities are available. Commissioning of this plant has been delayed while a defect in the air compressor supplied for the plant is being remedied. When the problem of liquid effluent disposal has been overcome, and if reagent chemicals continue to be available at reasonable prices, the Stretford process will be a good choice for coke oven gas desulphurization. 8 figures.

Plenderleith, J.

1981-01-01T23:59:59.000Z

59

Innovative coke oven gas cleaning system for retrofit applications  

Science Conference Proceedings (OSTI)

Bethlehem Steel Corporation (BSC), in conjunction with the Department of Energy (DOE) is conducting a Clean Coal Technology (CCT) project at its Sparrows Point, Maryland Coke Oven Plant. This project combines several existing technologies into an integrated system for removing impurities from Coke Oven Gas (COG) to make it an acceptable fuel. DOE is providing cost-sharing under a Cooperative Agreement with BSC. This Cooperative Agreement requires BSC to develop and conduct an Environmental Monitoring Plan (EMP) for the Clean Coal Technology project and to report the status of the EMP on a quarterly basis. This report is the third quarterly status report of the EMP. It covers the Environmental Monitoring Plan activities for the full year of 1991 from January 1, 1991 through December 31, 1991, including the forth quarter. See Sections 2, 3 and 4 for status reports of the Project Installation and Commissioning, the Environmental Monitoring activities and the Compliance Monitoring results for the period. Section 5 contains a list of Compliance Reports submitted to regulatory agencies during the period. The EMP describes in detail the environmental monitoring activities to be performed during the project execution. The purpose of the EMP is to: (1) document the extent of compliance of monitoring activities, i.e. those monitoring required to meet permit requirements, (2) confirm the specific impacts predicted in the National Environmental Policy Act documentation, and (3) establish an information base for the assessment of the environmental performance of the technology demonstrated by the project.

Not Available

1992-10-16T23:59:59.000Z

60

Model reference adaptive temperature control of the electromagnetic oven process in manufacturing process  

Science Conference Proceedings (OSTI)

Nowadays, the electromagnetic ovens are used for heating the component assembly of electronic manufacturing. The control systems of the electromagnetic ovens are feedback control system and PID controller are used to control their temperature. This process ... Keywords: control theory, response optimization and model reference adaptive system

Jiraphon Srisertpol; Supot Phungphimai

2010-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Organic Sulphur Transfers in Coke Oven Gas via Noncatalytic Partial Oxidation  

Science Conference Proceedings (OSTI)

The organic sulfur transformation was studied during coke oven gas to produce syngas via noncatalytic partial oxidation. The concentration of CS2 and thiophene was examined in syngas by sulfide detector. For comparison, the sulfur transfer was also studied ... Keywords: Organic sulfur transfer, Coke oven gas, CS2, thiophene

Guojie Zhang; Yongfa Zhang; Xianglan Li; Hongcheng Cao

2009-10-01T23:59:59.000Z

62

Coke oven gas desulphurization by the Carl Still process  

SciTech Connect

The Steubenville East Coke Plant need a desulfurization process that would desulfurize an eventual 95 million standard cubic feet per day of coke oven gas from an inlet of 450 gr/DSCF to an outlet of 45 gr/DSCF of hydrogen sulfide. The Dravo/Still plant process was selected, due to the use of ammonia which was available in the gas, as the absorbing agent. It was also a proven process. Dravo/Still also was capable of building a sulfuric acid plant. The desulfurization efficiency of the plant has consistently provided an average final gas sulfur loading below the guaranteed 45 gr/DSCF. This removal efficiency has enabled production of an average of 4615 tons per day of 66/sup 0/Be acid. Also SO/sub 2/ to SO/sub 3/ conversion has averaged 98%. 3 figures. (DP)

Knight, R.E.

1981-01-01T23:59:59.000Z

63

Method for removing hydrogen sulfide from coke oven gas  

Science Conference Proceedings (OSTI)

An improved sulfur-ammonia process is disclosed for removing hydrogen sulfide from coke oven gases. In the improved process, a concentrator formerly used for standby operation is used at all normal times as an ammonia scrubber to improve the efficiency of gas separation during normal operation and is used as a concentrator for its intended standby functions during the alternative operations. In its normal function, the concentrator/scrubber functions as a scrubber to strip ammonia gas from recirculating liquid streams and to permit introduction of an ammonia-rich gas into a hydrogen sulfide scrubber to increase the separation efficiency of that unit. In the standby operation, the same concentrator/scrubber serves as a concentrator to concentrate hydrogen sulfide in a ''strong liquor'' stream for separate recovery as a strong liquor.

Ritter, H.

1982-08-03T23:59:59.000Z

64

A compact and efficient strontium oven for laser-cooling experiments  

E-Print Network (OSTI)

Here we describe a compact and efficient strontium oven well suited for laser-cooling experiments. Novel design solutions allowed us to produce a collimated strontium atomic beam with a flux of 1.0\\times10^13 s^-1 cm^-2 at the oven temperature of 450 {\\deg}C, reached with an electrical power consumption of 36 W. The oven is based on a stainless-steel reservoir, filled with 6 g of metallic strontium, electrically heated in a vacuum environment by a tantalum wire threaded through an alumina multi-bore tube. The oven can be hosted in a standard DN40CF cube and has an estimated continuous operation lifetime of 10 years. This oven can be used for other alkali and alkaline earth metals with essentially no modifications.

Marco Schioppo; Nicola Poli; Marco Prevedelli; Stephan Falke; Christian Lisdat; Uwe Sterr; Guglielmo Maria Tino

2012-09-25T23:59:59.000Z

65

A compact and efficient strontium oven for laser-cooling experiments  

E-Print Network (OSTI)

Here we describe a compact and efficient strontium oven well suited for laser-cooling experiments. Novel design solutions allowed us to produce a collimated strontium atomic beam with a flux of 1.0\\times10^13 s^-1 cm^-2 at the oven temperature of 450 {\\deg}C, reached with an electrical power consumption of 36 W. The oven is based on a stainless-steel reservoir, filled with 6 g of metallic strontium, electrically heated in a vacuum environment by a tantalum wire threaded through an alumina multi-bore tube. The oven can be hosted in a standard DN40CF cube and has an estimated continuous operation lifetime of 10 years. This oven can be used for other alkali and alkaline earth metals with essentially no modifications.

Schioppo, Marco; Prevedelli, Marco; Falke, Stephan; Lisdat, Christian; Sterr, Uwe; Tino, Guglielmo Maria

2012-01-01T23:59:59.000Z

66

Developing indicators for the assessment and proper management of the different levels of exposure to polycyclic aromatic hydrocarbons (PAH)s generally associated with coke-oven workers.  

E-Print Network (OSTI)

??Coke ovens may occur in the aluminium, steel, graphite, electrical, and construction industries. In the work area coke-oven workers may be exposed to various chemical… (more)

Wang, Tianyuan

2011-01-01T23:59:59.000Z

67

Coke oven gas desulfurization: at Republic Steel's New Coking Facility, Warren, OH  

SciTech Connect

Our performance test indicates that the Sulfiban process is an effective method for removing H/sub 2/S from coke-oven gas. The process is able to handle variations in coke-oven gas flow and composition. Continuing efforts are underway to maintain optimum desulfurization conditions while trying to reduce waste production and MEA consumption. The problems which have prevented us from operating continuously have given us a better understanding of the process. This has contributed to better plant operations and greater equipment reliability for us to obtain continuous coke-oven gas desulfurization. 2 figures, 1 table.

Boak, S.C.; Prucha, D.G.; Turic, H.L.

1981-01-01T23:59:59.000Z

68

Testing of the Sunstove Organization's Sunstove Solar Oven  

E-Print Network (OSTI)

A Sunstove Organization's Sunstove was tested at Sandia's Solar Thermal Test Facility. It was instrumented with five type K thermocouples to determine warm-up rates when empty and when a pot containing two liters of water was placed inside. It reached inside air temperatures above 115 o C (240 o F). It heated two liters of water from room temperature to 80 o C (175 o F) in about two hours. Observations were made on the cooling and reheating rates during a cloud passage. The adverse effects of wind on the operation of the solar oven were also noted. ii 1 The Solar Thermal Design Assistance Center (STDAC) at Sandia National Laboratories evaluated a Sunstove from the Sunstove Organization, at Sandia's Solar Thermal Test Facility in Albuquerque NM. It was designed for single family household cooking. It is targeting developing countries' alternative energy markets where conventional fuels are not available and wood is the primary fuel used for cooking. Because of the wide vari...

Moss Solar Thermal; T. A. Moss

1997-01-01T23:59:59.000Z

69

A modular phase change heat exchanger for a solar oven  

Science Conference Proceedings (OSTI)

A modular energy storing heat exchanger designed to use pentaerythritol for thermal storage (solid-solid phase change at 182 C) is tested in an oven by circulating heat transfer oil which is electrically heated in a manner to simulate a concentrating solar collector. Three efficiencies for heating the system under controlled and measured power input are determined - the heat exchanger efficiency, the efficiency of the heater with distribution lines, and the total system efficiency. Thermal energy retention times and cooking extraction times are determined, and along with the efficiencies, are compared with the results previously reported for a nonmodular heat exchanger. The modular configuration provides a highly improved extraction rate for cooking due to its wrap-around character and its increased surface-to-volume ratio. A full scale glass model of the copper tubing of the system is described and flow observations reported demonstrating how uniformly the parallel pumping branches perform and how trapped air pockets affect pumping power. A technique for measuring pumping power is described and its application to the system is quantified to show that less than 1 watt is required to circulate the heat transfer oil even when the system includes the solar collector and its longer connecting tubes.

Bushnell, D.L.; Sohi, M. (Northern Illinois Univ., DeKalb (United States))

1992-10-01T23:59:59.000Z

70

New Energy Efficiency Standards for Microwave Ovens to Save Consumers on  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Energy Efficiency Standards for Microwave Ovens to Save Energy Efficiency Standards for Microwave Ovens to Save Consumers on Energy Bills New Energy Efficiency Standards for Microwave Ovens to Save Consumers on Energy Bills May 31, 2013 - 3:26pm Addthis NEWS MEDIA CONTACT (202) 586-4940 WASHINGTON - U.S. Energy Secretary Ernest Moniz announced today that the Energy Department has finalized new energy efficiency standards for microwave ovens that will save consumers nearly $3 billion on their energy bills through 2030. Over the next 30 years, it will dramatically reduce harmful carbon pollution, equivalent to taking over 12 million new cars off the road for one year. "Appliance efficiency standards represent a huge opportunity to help families save money by saving energy, while still delivering high quality

71

Bethlehem Steel announces plans to control coke oven air and water pollution  

Science Conference Proceedings (OSTI)

Bethlehem Steel Corporation and the Maryland Department of the Environment have announced an agreement under which Bethlehem will spend an estimated $92-million at its Sparrows Points, Md., plant for technologically-advanced controls to further reduce air and water pollution, mainly from the plant's coke ovens. The two major systems include one to treat by-product coke oven gas and chemicals, and another to upgrade existing pushing emission controls on two older coke oven batteries. One of the new systems will replace most of the existing equipment that cleans gas and treats chemicals created by the coking process at the plant's three coke oven batteries. Because this system has the potential to greatly reduce sulfur dioxide and other pollutants, the United States Department of Energy (DOE) in September announced that its installation qualified for funding as part of the nationwide Innovative Clean Coal Technology Program.

Not Available

1989-08-01T23:59:59.000Z

72

Electromagnetic and Heat Transfer Modeling of Microwave Heating in Domestic Ovens.  

E-Print Network (OSTI)

??Microwave (MW) ovens are used extensively for heating a variety of not-ready-to-eat food products. It is vital to achieve target temperature uniformly throughout the food… (more)

Pitchai, Krishnamoorthy

2011-01-01T23:59:59.000Z

73

Modeling Infrared and Combination Infrared-Microwave Heating of Foods in an Oven .  

E-Print Network (OSTI)

??A quantitative, model-based understanding of heat exchange in infrared and combined infrared-microwave heating of food inside an oven is developed. The research is divided into… (more)

Frangipani Almeida, Marialuci

2004-01-01T23:59:59.000Z

74

Additional Steam Traps Increase Production of a Drum Oven at a Petroleum Jelly Plant  

Science Conference Proceedings (OSTI)

Additional steam traps were installed on the drum oven at a petroleum jelly production facility at an ExxonMobil plant in Nigeria. The installation improved heat transfer and saved energy.

Not Available

2002-03-01T23:59:59.000Z

75

Created March 2009 Microwave ovens are located throughout Swinburne University campuses in both staff & students  

E-Print Network (OSTI)

as when sealed containers are heated they may explode and damage the oven rendering it unsafe. · Use glass containers designed for microwaves to cook high-fat foods, as additives from plastic are more likely

Liley, David

76

Acoustic emission feedback control for control of boiling in a microwave oven  

DOE Patents (OSTI)

An acoustic emission based feedback system for controlling the boiling level of a liquid medium in a microwave oven is provided. The acoustic emissions from the medium correlated with surface boiling is used to generate a feedback control signal proportional to the level of boiling of the medium. This signal is applied to a power controller to automatically and continuously vary the power applied to the oven to control the boiling at a selected level. 2 figs.

White, T.L.

1990-05-02T23:59:59.000Z

77

Acoustic emission feedback control for control of boiling in a microwave oven  

DOE Patents (OSTI)

An acoustic emission based feedback system for controlling the boiling level of a liquid medium in a microwave oven is provided. The acoustic emissions from the medium correlated with surface boiling is used to generate a feedback control signal proportional to the level of boiling of the medium. This signal is applied to a power controller to automatically and continuoulsly vary the power applied to the oven to control the boiling at a selected level.

White, Terry L. (Oak Ridge, TN)

1991-01-01T23:59:59.000Z

78

A new technology for producing hydrogen and adjustable ratio syngas from coke oven gas  

Science Conference Proceedings (OSTI)

About 15 billion Nm{sup 3} coke oven gas (COG) is emitted into the air in Shanxi Province in China as air pollutants. It is also a waste of precious chemical resources. In this study, COG was purified respectively by four methods including refrigeration, fiberglass, silica gel, and molecular sieve. Purified COG was separated by a prism membrane into two gas products. One consists mainly of H{sub 2} ({gt}90 vol %) and the other is rich in CH{sub 4} ({gt}60 vol %) with their exact compositions to vary with the membrane separation pressure and outlet gas flow ratio. The gas rich in CH{sub 4} was partially oxidized with oxygen in a high-temperature fixed-bed quartz reactor charged with coke particles of 10 mm size. At 1200-1300{sup o}C, a CH{sub 4} conversion of {gt}99% could be obtained. The H{sub 2}/CO ratio in the synthesis product gas can be adjusted in the range 0.3-1.4, very favorable for further C1 synthesis. 10 refs., 17 figs., 1t ab.

Jun Shen; Zhi-zhong Wang; Huai-wang Yang; Run-sheng Yao [Taiyuan University of Technology, Taiyuan (China). Department of Chemical Engineering

2007-12-15T23:59:59.000Z

79

Hydrogen production from simulated hot coke oven gas by using oxygen-permeable ceramics  

SciTech Connect

Hydrogen production from simulated hot coke oven gas (HCOG) was investigated in a BaCo{sub 0.7}Fe{sub 0.2}Nb{sub 0.1}O{sub 3-{delta}} (BCFNO) membrane reactor combined with a Ni/Mg(Al)O catalyst by the partial oxidation with toluene as a model tar compound under atmospheric pressure. The reaction results indicated that toluene was completely converted to H{sub 2} and CO in the catalytic reforming of the simulated HCOG in the temperature range from 825 to 875{sup o}C. Both thermodynamically predicated values and experimental data showed that the selective oxidation of toluene took precedence over that of CH{sub 4} in the reforming reaction. At optimized reaction conditions, the dense oxygen-permeable membrane has an oxygen permeation flux around 12.3 mL cm{sup -2} min{sup -1}, and a CH{sub 4} conversion of 86%, a CO{sub 2} conversion of 99%, a H{sub 2} yield of 88%, and a CO yield of 87% have been achieved. When the toluene and methane were reformed, the amount of H{sub 2} in the reaction effluent gas was about 2 times more than that of original H{sub 2} in simulated HCOG. The results reveal that it is feasible for hydrogen production from HCOG by reforming hydrocarbon compounds in a ceramic oxygen-permeable membrane reactor. 27 refs., 10 figs., 3 abs.

Hongwei Cheng; Yuwen Zhang; Xionggang Lu; Weizhong Ding; Qian Li [Shanghai University, Shanghai (China). Shanghai Key Laboratory of Modern Metallurgy and Materials Processing

2009-01-15T23:59:59.000Z

80

Restratification after Deep Convection  

Science Conference Proceedings (OSTI)

An important, yet poorly understood, aspect of the water mass transformation process in the ocean is the manner in which the convected fluid, once formed, is accommodated and drawn into the general circulation. Following “violent mixing” in the ...

Helen Jones; John Marshall

1997-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Impact of Stochastic Physics in a Convection-Permitting Ensemble  

Science Conference Proceedings (OSTI)

A stochastic physics scheme is tested in the Application of Research to Operations at Mesoscale (AROME) short-range convection-permitting ensemble prediction system. It is an adaptation of ECMWF’s stochastic perturbation of physics tendencies (...

François Bouttier; Benoît Vié; Olivier Nuissier; Laure Raynaud

2012-11-01T23:59:59.000Z

82

Airborne Doppler Lidar Observations of Convective Phenomena in Oklahoma  

Science Conference Proceedings (OSTI)

On 30 June 1981, the wind fields around a variety of convective clouds, ranging from large thunderstorm complexes to isolated cumulus congestus, were observed in Oklahoma using an airborne Doppler lidar operated by the National Aeronautics and ...

Eugene W. McCaul Jr.; Howard B. Bluestein; Richard J. Doviak

1987-09-01T23:59:59.000Z

83

Deep Convective Rotational Solitary Waves and Mesoscale Convective Complexes  

Science Conference Proceedings (OSTI)

As an extension of CCI (conditional convective instability) theory, three-dimensional, deep and steady convective waves in a barotropic basic flow with an embedded moist zone were studied via perturbation methods. The basic state is assumed to be ...

Qin Xu

1987-06-01T23:59:59.000Z

84

Convection Patterns in a Pond  

Science Conference Proceedings (OSTI)

Unusual convection patterns were observed in snow-slush an a pond in Seattle, Wash., during January 1980 and again during February 1981. The patterns are reminiscent of spoke-type convection discovered experimentally by Busse and Whitehead (1974)...

Kristina B. Katsaros

1981-10-01T23:59:59.000Z

85

NATURAL CONVECTION IN ROOM GEOMETRIES  

E-Print Network (OSTI)

that convective heat transfer processes are These computer~vective .part of the heat transfer process ? elng studled*of convect i ve heat transfer processes, the behavior of a

Gadgil, A.

2008-01-01T23:59:59.000Z

86

The Convective Storm Initiation Project  

Science Conference Proceedings (OSTI)

The Convective Storm Initiation Project (CSIP) is an international project to understand precisely where, when, and how convective clouds form and develop into showers in the mainly maritime environment of southern England. A major aim of CSIP is ...

Keith A. Browning; Cyril J. Morcrette; John Nicol; Alan M. Blyth; Lindsay J. Bennett; Barbara J. Brooks; John Marsham; Stephan D. Mobbs; Douglas J. Parker; Felicity Perry; Peter A. Clark; Sue P. Ballard; Mark A. Dixon; Richard M. Forbes; Humphrey W. Lean; Zhihong Li; Nigel M. Roberts; Ulrich Corsmeier; Christian Barthlott; Bernhard Deny; Norbert Kalthoff; Samiro Khodayar; Martin Kohler; Christoph Kottmeier; Stephan Kraut; Michael Kunz; Jürgen Lenfant; Andreas Wieser; Judith L. Agnew; Dave Bamber; James McGregor; Karl M. Beswick; Malcolm D. Gray; Emily Norton; Hugo M. A. Ricketts; Andrew Russell; Geraint Vaughan; Ann R. Webb; Mark Bitter; Thomas Feuerle; Rolf Hankers; Helmut Schulz; Karen E. Bozier; Chris G. Collier; Fay Davies; Catherine Gaffard; Tim J. Hewison; Darcy N. Ladd; Elizabeth C. Slack; Joe Waight; Markus Ramatschi; David P. Wareing; Robert J. Watson

2007-12-01T23:59:59.000Z

87

The use of ethylenediamine to remove hydrogen sulfide from coke oven gas  

Science Conference Proceedings (OSTI)

The investigations of the equilibrium absorption of H/sub 2/S by an EDA solution showed the solubility of hydrogen sulfide in ethylenediamine solutions is almost twice that in monoethanolamine solutions. Ethylenediamine may be used as an absorber for thorough removal of H/sub 2/S from coke oven gas in the presence of CO/sub 2/ and HCN. The hydrogen cyanide of coke oven gas, having practically no effect on the equilibrium absorption of H/sub 2/S and CO/sub 2/, may in this case be used in the form of ethylenethiourea - a marketable byproduct.

Marakhovskii, L.F.; Rezunenko, Y.I.; Popov, A.A.

1983-01-01T23:59:59.000Z

88

Use of ethylenediamine to remove hydrogen sulfide from coke oven gas  

SciTech Connect

The investigations of the equilibrium absorption of H/sub 2/S by an EDA solution which show that the solubility of hydrogen sulfide in ethylenediamine solutions is almost twice that in monoethanolamine solutions. Ethylenediamine may be used as an absorber for thorough removal of H/sub 2/S from coke oven gas in the presence of CO/sub 2/ and HCN. The hydrogen cyanide of coke oven gas, having practically no effect on the equilibrium absorption of H/sub 2/S and CO/sub 2/, may in this case be recovered in the form of ethylenethiourea - a marketable byproduct.

Marakhovskii, L.F.; Popov, A.A.; Rezunenko, Yu.I.

1983-01-01T23:59:59.000Z

89

5, 1102911054, 2005 Convective gravity  

E-Print Network (OSTI)

ACPD 5, 11029­11054, 2005 Convective gravity waves at mid-latitudes Y. G. Choi et al. Title Page Discussions Wind-profiler observations of gravity waves produced by convection at mid-latitudes Y. G. Choi1­11054, 2005 Convective gravity waves at mid-latitudes Y. G. Choi et al. Title Page Abstract Introduction

Paris-Sud XI, Université de

90

Innovative coke oven gas cleaning system for retrofit applications. Volume 1, Public design report  

SciTech Connect

This Public Design Report provides, in a single document, available nonproprietary design -information for the ``Innovative Coke Oven Gas Cleaning System for Retrofit Applications`` Demonstration Project at Bethlehem Steel Corporation`s Sparrows Point, Maryland coke oven by-product facilities. This project demonstrates, for the first time in the United States, the feasibility of integrating four commercially available technologies (processes) for cleaning coke oven gas. The four technologies are: Secondary Gas Cooling, Hydrogen Sulfide and Ammonia Removal, Hydrogen Sulfide and Ammonia Recovery, and Ammonia Destruction and Sulfur Recovery. In addition to the design aspects, the history of the project and the role of the US Department of,Energy are briefly discussed. Actual plant capital and projected operating costs are also presented. An overview of the integration (retrofit) of the processes into the existing plant is presented and is followed by detailed non-proprietary descriptions of the four technologies and their overall effect on reducing the emissions of ammonia, sulfur, and other pollutants from coke oven gas. Narrative process descriptions, simplified process flow diagrams, input/output stream data, operating conditions, catalyst and chemical requirements, and utility requirements are given for each unit. Plant startup provisions, environmental considerations and control monitoring, and safety considerations are also addressed for each process.

Not Available

1994-05-24T23:59:59.000Z

91

Modeling of Microwave Ovens with Perforated Metal Walls Erin M. Kiley and Vadim V. Yakovlev  

E-Print Network (OSTI)

engineers developing new microwaveable products. This can be explained by the particularly complex nature, modeling. I. INTRODUCTION While historically, technological progress in microwave power engineering has microwave ovens - the most widespread microwave heating devices - have not yet been notably adopted by food

Yakovlev, Vadim

92

Commercial Kitchen Ventilation Performance Report: Electric Combination Oven Under Wall-Mounted Canopy Hood  

Science Conference Proceedings (OSTI)

This report documents testing of ventilation requirements for an electric combination oven under an exhaust-only canopy hood. This appliance and hood combination is one of a series undertaken to provide electric utilities and the foodservice industry with data to optimize the design of commercial kitchen ventilation systems and integrate exhaust requirements with space conditioning design.

1997-11-14T23:59:59.000Z

93

Commercial Kitchen Ventilation Performance Report: Gas Combination Oven Under Wall-Mounted Canopy Hood  

Science Conference Proceedings (OSTI)

This report documents testing of ventilation requirements for a gas combination oven under an exhaust-only canopy hood. This appliance and hood combination is one of a series undertaken to provide electric utilities and the foodservice industry with data to optimize the design of commercial kitchen ventilation systems and integrate exhaust requirements with space conditioning design.

1997-11-14T23:59:59.000Z

94

WELL BEING WEDNESDAY Oven Baked Chicken Tandoori with Side Salad, Fresh Lime &  

E-Print Network (OSTI)

WELL BEING WEDNESDAY Low Fat Oven Baked Chicken Tandoori with Side Salad, Fresh Lime & Homemade with a reduced Fat Tomato Sauce HM V £3.80 Jacket Potato Fillings Low Fat Cottage Cheese Deli Style Coleslaw with Low Fat Mayonnaise Lean Mince Chilli Con Carne Grated Welsh Cheddar Tuna Mayonnaise ­ (responsibly

Davies, Christopher

95

NATURAL CONVECTION IN PASSIVE SOLAR BUILDINGS: EXPERIMENTS, ANALYSIS AND RESULTS  

E-Print Network (OSTI)

convection process and calculate convective heat transferthat convective heat transfer processes are highly dependentheat transfer process being studied* and

Gadgil, Ashok; Bauman, Fred; Kammerud, Ronald

2008-01-01T23:59:59.000Z

96

Innovative coke oven gas cleaning system for retrofit applications: Environmental Monitoring Program. Volume 3, Appendix sections 8--14: Baseline Sampling Program report  

Science Conference Proceedings (OSTI)

This report contains no text. It consists entirely of numerical data: Coke oven wastewater treatment performance; Ammonia still effluents to equalization tank; Stack gas analysis of coke oven batteries; CoaL consumption; Coke production; Supplemental OSHA employee exposure monitoring(hydrocarbons,ammonia, hydrogen sulfide); operating data; chemical products and coke oven gas production.

Stuart, L.M.

1994-05-27T23:59:59.000Z

97

Build an oven, cook a meal: How solar energy empowered women in Costa Rica  

Science Conference Proceedings (OSTI)

A pilot solar cooking project in the hot, northern province of Guanacaste promises to serve as a model for community groups wanting to build their own solar ovens. An $8,000 (US) grant has been awarded by the Canadian Embassy in Costa Rica to take the Guanacaste project into a second stage in 1990-91. Two construction workshops, with twelve participants in each, are planned in communities near Oriente. Three women from the Oriente group will have paid jobs as organizational facilitators and workshop supervisors. In popular education this is called the multiplier effect - the users of solar cookers construct the ovens themselves, and then instruct others to do the same. 3 refs.

Blankenship, J. (Canadian Univ. Service Organization, San Jose (Costa Rica))

1990-12-01T23:59:59.000Z

98

Air pollution from a large steel factory: polycyclic aromatic hydrocarbon emissions from coke-oven batteries  

SciTech Connect

A systematic investigation of solid and gaseous atmospheric emissions from some coke-oven batteries of one of Europe's largest integrated steel factory (Taranto, Italy) has been carried out. These emissions, predominantly diffuse, originate from oven leakages, as well as from cyclic operations of coal loading and coke unloading. In air monitoring samples, polycyclic aromatic hydrocarbons (PAHs) were consistently detected at concentrations largely exceeding threshold limit values. By means of PAHs speciation profile and benzo-(a)pyrene (BaP) equivalent dispersion modeling from diffuse sources, the study indicated that serious health risks exist not only in working areas, but also in a densely populated residential district near the factory. 30 refs., 5 figs., 3 tabs.

Lorenzo Liberti; Michele Notarnicola; Roberto Primerano; Paolo Zannetti [Technical University of Bari, Bari (Italy). Department of Environmental Engineering and Sustainable Development

2006-03-15T23:59:59.000Z

99

Choosing a coke-oven gas desulfurization system: a review of current technology  

SciTech Connect

Installation of coke-oven gas desulphurizing systems is primarily the result of air pollution control regulations. Although not currently profitable, operating costs can be minimized by choosing the technology most suited to the particular application. The Stretford Holmes, Takahax/Hirohax, Koppers Vacuum Carbonate, Sulfiban and Dravo/Still processes are discussed, together with criteria for economic analysis based on technical and by-product market evaluations.

Lynch, P.A.

1982-12-01T23:59:59.000Z

100

Method of washing hydrogen sulfide from coke oven gas by the ammonium sulfide method  

Science Conference Proceedings (OSTI)

An improved coke oven gas washing process for removing hydrogen sulfide is proposed wherein the coke oven gas is treated in a hydrogen sulfide scrubber by counterflow with an aqueous ammonia wash water. A stream of aqueous weak ammonia liquor is cooled and sprayed through nozzles in the mid-region of the hydrogen sulfide scrubber. A quantity of aqueous ammonia liquor, corresponding to the quantity which is sprayed through the said nozzles, is withdrawn from the hydrogen sulfide scrubber at a level below the nozzles and is introduced into the top of the said hydrogen sulfide scrubber. Ammonia vapor released at the nozzles has a higher partial pressure than the ammonia partial pressure of the coke oven gas in the region of the nozzle. The aqueous ammonia liquor from the deacidifier is the source of the cooled aqueous ammonia liquor which is introduced through the nozzles. A portion of the aqueous ammonia liquor from the deacidifier is introduced directly into the top of the hydrogen sulfide scrubber as a portion of the required aqueous ammonia wash water.

Ritter, H.

1985-05-21T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Utilizing secondary heat to heat wash oil in the coke-oven gas desulfurization division  

SciTech Connect

Removal of hydrogen sulfide from the coke-oven gas by the vacuum-carbonate method involves significant energy costs, comprising about 47% of the total costs of the process. This is explained by the significant demand of steam for regeneration of the wash oil, the cost of which exceeds 30% of the total operating costs. The boiling point of the saturated wash oil under vacuum does not exceed 70/sup 0/C, thus the wash oil entering the regenerator can be heated either by the direct coke-oven gas or by the tar supernatant from the gas collection cycle. Utilizing the secondary heat of the direct coke-oven gas and the tar supernatant liquor (the thermal effect is approximately the same) to heat the wash oil from the gas desulfurization shops significantly improves the industrial economic indices. Heating the wash oil from gas desulfurization shops using the vacuum-carbonate method by the heat of the tar supernatant liquor may be adopted at a number of coking plants which have a scarcity of thermal resources and which have primary coolers with vertical tubes.

Volkov, E.L.

1981-01-01T23:59:59.000Z

102

Design and operation of the coke-oven gas sulfur removal facility at Geneva Steel  

Science Conference Proceedings (OSTI)

The coke-oven gas sulfur removal facility at Geneva Steel utilizes a combination of two technologies which had never been used together. These two technologies had proven effective separately and now in combination. However, it brought unique operational considerations which has never been considered previously. The front end of the facility is a Sulfiban process. This monoethanolamine (MEA) process effectively absorbs hydrogen sulfide and other acid gases from coke-oven gas. The final step in sulfur removal uses a Lo-Cat II. The Lo-Cat process absorbs and subsequently oxidizes H{sub 2}S to elemental sulfur. These two processes have been effective in reducing sulfur dioxide emissions from coke-oven gas by 95%. Since the end of the start-up and optimization phase, emission rate has stayed below the 104.5 lb/hr limit of equivalent SO{sub 2} (based on a 24-hr average). In Jan. 1995, the emission rate from the sulfur removal facility averaged 86.7 lb/hr with less than 20 lb/hr from the Econobator exhaust. The challenges yet to be met are decreasing the operating expenses of the sulfur removal facility, notably chemical costs, and minimizing the impact of the heating system on unit reliability.

Havili, M.U.; Fraser-Smyth, L.L.; Wood, B.W. [Geneva Steel, Provo, UT (United States)

1996-02-01T23:59:59.000Z

103

Convective Modifications of a Geostrophic Eddy Field  

Science Conference Proceedings (OSTI)

Ocean convection often occurs in regions of mesoscale eddy activity, where convective mixing and geostrophic eddy dynamics interact. The authors examine the interactions between a group of geostrophic eddies and convective mixing induced by ...

Sonya Legg; James C. McWilliams

2001-04-01T23:59:59.000Z

104

Tropical Convective Variability as 1/f Noise  

Science Conference Proceedings (OSTI)

Evidence is presented that the tropical convective variability behaves as 1/f noise for a 1–30-day period. This behavior is shown by analyzing the time series of convective available potential energy, which measures the degree of convective ...

Jun-Ichi Yano; Klaus Fraedrich; Richard Blender

2001-09-01T23:59:59.000Z

105

VARIATION OF STELLAR ENVELOPE CONVECTION AND OVERSHOOT WITH METALLICITY  

SciTech Connect

We examine how metallicity affects convection and overshoot in the superadiabatic layer of main sequence stars. We present results from a grid of three-dimensional radiation hydrodynamic simulations with four metallicities (Z = 0.040, 0.020, 0.010, 0.001), and spanning a range in effective temperature (4950 < T{sub eff} < 6230). We show that changing the metallicity alters properties of the convective gas dynamics, and the structure of the superadiabatic layer and atmosphere. Our grid of simulations shows that the amount of superadiabaticity, which tracks the transition from efficient to inefficient convection, is sensitive to changes in metallicity. We find that increasing the metallicity forces the location of the transition region to lower densities and pressures, and results in larger mean and turbulent velocities throughout the superadiabatic region. We also quantify the degree of convective overshoot in the atmosphere, and show that it increases with metallicity as well.

Tanner, Joel D.; Basu, Sarbani; Demarque, Pierre [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)] [Department of Astronomy, Yale University, P.O. Box 208101, New Haven, CT 06520-8101 (United States)

2013-04-10T23:59:59.000Z

106

Improving Convective Parameterization Using ARM Data  

NLE Websites -- All DOE Office Websites (Extended Search)

Convective Parameterization Using ARM Data G. J. Zhang Center for Atmospheric Sciences Scripps Institution of Oceanography La Jolla, California Introduction Convective...

107

Final environmental information volume for the coke oven gas cleaning project at the Bethlehem Steel Corporation Sparrows Point Plant  

Science Conference Proceedings (OSTI)

Bethelehem Steel Corporation (BSC) is planning to conduct a demonstration project involving an integrated system that can be retrofitted into coke oven gas handling systems to address a variety of environmental and operational factors in a more cost-effective manner. Successful application of this technology to existing US coke plants could: (1) reduce emissions of sulfur dioxide, cyanide, and volatile organic compounds (including benzene) (2) reduce the cost and handling of processing feed chemicals, (3) disposal costs of nuisance by-products and (4) increase reliability and reduce operation/maintenance requirements for coke oven gas desulfurization systems. The proposed system will remove sulfur from the coke oven gas in the form of hydrogen sulfide using the ammonia indigenous to the gas as the primary reactive chemical. Ammonia and hydrogen cyanide are also removed in this process. The hydrogen sulfide removed from the coke oven gas in routed to a modified Claus plant for conversion to a saleable sulfur by-product. Ammonia and hydrogen cyanide will be catalytically converted to hydrogen, nitrogen, carbon dioxide, and carbon monoxide. The tail gas from the sulfur recovery unit is recycled to the coke oven gas stream, upstream of the new gas cleaning system. The proposed demonstration project will be installed at the existing coke oven facilities at BSC's Sparrows Point Plant. This volume describes the proposed actions and the resulting environmental impacts. 21 refs., 19 figs., 9 tabs.

Not Available

1990-04-24T23:59:59.000Z

108

Liquid convective diodes  

DOE Green Energy (OSTI)

Liquid convective diodes are analyzed by experiments and theory. The experiments include flow visualization and temperature measurements. The dynamic behavior of a diode is analyzed and explained. Performance of three diodes of different designs that were installed in a test cell this past winter showed an average 50% thermal efficiency over a three-month period. If only the performance of the most efficient diode among the three is considered, it is expected that this figure may be increased to 60% or possibly 65% with some design improvements. A simple analytical model, which was developed earlier, is discussed. A comparison of reservoir temperatures from one of the test cell diodes with predicted temperatures from the model showed excellent agreement. The good agreement indicates that the model contains the elements that are necessary to accurately predict site-specific diode performance.

Jones, G.F.

1984-01-01T23:59:59.000Z

109

A Numerical Simulation of Convectively Induced Turbulence above Deep Convection  

Science Conference Proceedings (OSTI)

At 1034 UTC 2 September 2007, a commercial aircraft flying from Jeju, South Korea, to Osaka, Japan, at an altitude of approximately 11.2 km encountered severe turbulence above deep convection. To investigate the characteristics and generation ...

Jung-Hoon Kim; Hye-Yeong Chun

2012-06-01T23:59:59.000Z

110

Convection in pulsating stars. II. RR Lyrae convection and stability  

Science Conference Proceedings (OSTI)

Convective model envelopes of two RR Lyrae stars are constructed, one centrally located in the instability strip, and one just beyond the red edge of the stip. Steady state solutions and small amplitude oscillations are studied using a nonlinear pulsation code. We find that convection has only a small effect on the stability of the hotter model, primarily due to turbulent pressure work (net driving) in the hydrogen ionization zone. The cooler model, however, shows strong reduction in both hydrogen and helium ionization driving, which quenches the pulsation. This effect is not directly attributable to convective PdV work, but probably reflects changes in structure and phase relations in the envelope due to convection.

Stellingwerf, R.F.

1982-11-01T23:59:59.000Z

111

Idealized Mesoscale Convective System Structure and Propagation Using Convective Parameterization  

Science Conference Proceedings (OSTI)

The development and propagation of mesoscale convective systems (MCSs) was examined within the Weather Research and Forecasting (WRF) model using the Kain–Fritsch (KF) cumulus parameterization scheme and a modified version of this scheme. ...

James Correia Jr.; Raymond W. Arritt; Christopher J. Anderson

2008-07-01T23:59:59.000Z

112

Heat distribution by natural convection  

DOE Green Energy (OSTI)

Natural convection between spaces in a building can play a major role in energy transfer. Two situations are investigated: convection through a single doorway into a remote room, and a convective loop in a two-story house with a south sunspace where a north stairway serves as the return path. A doorway-sizing equation is given for the single-door case. Detailed data are given from the monitoring of airflow in one two-story house and summary data are given for five others. Observations on the nature of the airflow and design guidelines are presented.

Balcomb, J.D.; Yamaguchi, K.

1983-01-01T23:59:59.000Z

113

Theories of convection and the spectrum of turbulence in the solar photosphere  

E-Print Network (OSTI)

Classical theories of turbulence do not describe accurately inertial range scaling laws in turbulent convection and notably fail to model the shape of the turbulent spectrum of solar photospheric convection. To understand these discrepancies, a detailed study of scale-by-scale budgets in turbulent Rayleigh-B\\'enard convection is presented, with particular emphasis placed on anisotropy and inhomogeneity. A generalized Kolmogorov equation applying to convection is derived and its various terms are computed using numerical simulations of turbulent Boussinesq convection. The analysis of the isotropic part of the equation shows that the third-order velocity structure function is significantly affected by buoyancy forcing and large-scale inhomogeneities. Anisotropic contributions to this equation are also shown to be comparable to their isotropic counterpart at moderate to large scales. Implications of these results for convection in the solar photosphere, mesogranulation and supergranulation are discussed.

F. Rincon

2006-11-28T23:59:59.000Z

114

Review: Convective heat and mass exchange predictions at leaf surfaces: Applications, methods and perspectives  

Science Conference Proceedings (OSTI)

Convective heat and mass exchange of leaves with the environment is relevant for a better understanding of plant physiological processes in response to environmental factors for a wide range of applications. Methods for quantifying these exchanges have ... Keywords: Artificial leaf, Convective transfer coefficient, Plant, Review, Stomata, Transpiration

Thijs Defraeye, Pieter Verboven, Quang Tri Ho, Bart Nicolai

2013-08-01T23:59:59.000Z

115

A dual mass flux framework for boundary layer convection  

NLE Websites -- All DOE Office Websites (Extended Search)

A dual mass flux framework for boundary layer convection A dual mass flux framework for boundary layer convection Neggers, Roel European Centre for Medium-range Weather Forecasts (ECMWF) Category: Modeling A new convective boundary layer scheme is presented that is currently being developed for the Integrated Forecasting System (IFS) of the European Centre for Medium-range Weather Forecasts (ECMWF). Part of the total turbulent flux is modeled through advective mass flux by multiple updrafts, initialized at the surface. Two groups of updrafts are explicitly represented; i) updrafts that never reach their lifting condensation level, and ii) updrafts that condensate and become cloudy. Key new ingredient is the flexibility of the associated updraft area fractions, as a function of model state. As a result, an extra degree of freedom is introduced in the

116

Reduction of NO[sub x] emissions coke oven gas combustion process  

SciTech Connect

The paper describes by-product processing at Clairton Works which uses a unique cryogenic technology. Modifications to the desulfurization facility, nitrogen oxide formation in combustion processes (both thermal and fuel NO[sub x]), and the boilers plants are described. Boilers were used to study the contribution of fuel NO[sub x] formation during the combustion of coke oven gas. Results are summarized. The modifications made to the desulfurization facility resulted in the overall H[sub 2]S emission being reduced by 2-4 grains/100scf and the NO[sub x] emission being reduced by 21-42% in the boiler stacks.

Terza, R.R. (USS Clairton Works, PA (United States)); Sardesai, U.V. (Westfield Engineering and Services, Inc., Houston, TX (United States))

1993-01-01T23:59:59.000Z

117

Mesoscale Convective Complexes in Africa  

Science Conference Proceedings (OSTI)

Digitized full-disk infrared satellite imagery from the European geostationary satellite (Meteosat) for 1986 and 1987 was used to construct a climatology of mesoscale convective complexes (MCCs) in Africa One hundred ninety-five systems formed ...

Arlene G. Laing; J. Michael Fritsch

1993-08-01T23:59:59.000Z

118

Isentropic Analysis of Convective Motions  

Science Conference Proceedings (OSTI)

This paper analyzes the convective mass transport by sorting air parcels in terms of their equivalent potential temperature to determine an isentropic streamfunction. By averaging the vertical mass flux at a constant value of the equivalent ...

Olivier M. Pauluis; Agnieszka A. Mrowiec

2013-11-01T23:59:59.000Z

119

The Transition to Strong Convection  

Science Conference Proceedings (OSTI)

Recent work has shown that observations of tropical precipitation conform to properties associated with critical phenomena in other systems. Here some of these universal properties are used to probe the physics of tropical convection empirically, ...

J. David Neelin; Ole Peters; Katrina Hales

2009-08-01T23:59:59.000Z

120

Integral Effects of Deep Convection  

Science Conference Proceedings (OSTI)

The large-scale, integral effect of convective elements (plumes) constituting an open-ocean chimney is investigated both theoretically and with a plume-resolving numerical model. The authors consider an initially homogeneous “patch” of ocean of ...

Uwe Send; John Marshall

1995-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

The Decay of Convective Turbulence  

Science Conference Proceedings (OSTI)

Using simulations with a large-eddy model we have studied the decay of convective turbulence in the atmospheric boundary layer when the upward surface sensible heat flux is suddenly stopped. The decay of turbulent kinetic energy and temperature ...

F. T. M. Nieuwstadt; R. A. Brost

1986-03-01T23:59:59.000Z

122

Convective heat flow probe  

DOE Patents (OSTI)

A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

Dunn, J.C.; Hardee, H.C.; Striker, R.P.

1984-01-09T23:59:59.000Z

123

The Impacts of Convective Parameterization and Moisture Triggering on AGCM-Simulated Convectively Coupled Equatorial Waves  

Science Conference Proceedings (OSTI)

This study examines the impacts of convective parameterization and moisture convective trigger on convectively coupled equatorial waves simulated by the Seoul National University (SNU) atmospheric general circulation model (AGCM). Three different ...

Jia-Lin Lin; Myong-In Lee; Daehyun Kim; In-Sik Kang; Dargan M. W. Frierson

2008-03-01T23:59:59.000Z

124

A Probabilistic Bulk Model of Coupled Mixed Layer and Convection. Part II: Shallow Convection Case  

Science Conference Proceedings (OSTI)

The probabilistic bulk convection model (PBCM) developed in a companion paper is here extended to shallow nonprecipitating convection. The PBCM unifies the clear-sky and shallow convection boundary layer regimes by obtaining mixed-layer growth, ...

Pierre Gentine; Alan K. Betts; Benjamin R. Lintner; Kirsten L. Findell; Chiel C. van Heerwaarden; Fabio D’Andrea

2013-06-01T23:59:59.000Z

125

Mountain-Induced Convection under Fair Weather Conditions  

Science Conference Proceedings (OSTI)

Measurements of the structure of dry convection over an isolated mountain range heated by the sun are presented. Filter techniques are used to deduce those scales of motion of significance to the circulation. A two-scale process is observed in ...

David Raymond; Marvin Wilkening

1980-12-01T23:59:59.000Z

126

Extended-Range Atmospheric Prediction and the Lorenz Model  

Science Conference Proceedings (OSTI)

The physical basis for extended-range prediction is explored using the famous three-component Lorenz convection model, taken as a conceptual representation of the chaotic extratropical circulation, and extended by coupling to a linear oscillator ...

T. N. Palmer

1993-01-01T23:59:59.000Z

127

Problem of sludge formation in benzol division solar oil and ''carbonization'' in coke oven gas compressor systems  

Science Conference Proceedings (OSTI)

A discussion is presented on the problem and possible causes of sludge formation in the return solar oil in benzene recovery units and on the problem of deposits in the pipe systems after coke oven gas compressors. The possible entrainment of fine particles of coal charge in the solar oil was also discussed. Sedimentation of the sludge was recommended with daily removal of the settled sludge. A chemical analysis of the deposits in the piping system of the coke oven gas and the coal charge revealed that the deposits were not caused by entrained coal particles. (JMT)

Rezunenko, Y.I.

1982-01-01T23:59:59.000Z

128

Horizontal Structure and Seasonality of Large-Scale Circulations Associated with Submonthly Tropical Convection  

Science Conference Proceedings (OSTI)

The relationship between deep tropical convection and large-scale atmospheric circulation in the 6–30-day period range is examined. Regression relationships between filtered outgoing longwave radiation at various locations in the Tropics and 200- ...

George N. Kiladis; Klaus M. Weickmann

1997-09-01T23:59:59.000Z

129

Role of Narrow Mountains in Large-Scale Organization of Asian Monsoon Convection  

Science Conference Proceedings (OSTI)

The Asian summer monsoon is organized into distinct convection centers, but the mechanism for this organization is not well understood. Analysis of new satellite observations reveals that narrow mountain ranges are an important organizing agent ...

Shang-Ping Xie; Haiming Xu; N. H. Saji; Yuqing Wang; W. Timothy Liu

2006-07-01T23:59:59.000Z

130

Objective Identification of Nonlinear Convectively Coupled Phases of Monsoon Intraseasonal Oscillation: Implications for Prediction  

Science Conference Proceedings (OSTI)

The nonlinear convectively coupled character of the summer monsoon intraseasonal oscillation (ISO) that manifests in its event-to-event variations is a major hurdle for skillful extended-range prediction of the active/break episodes. The ...

R. Chattopadhyay; A. K. Sahai; B. N. Goswami

2008-05-01T23:59:59.000Z

131

Convection-Allowing and Convection-Parameterizing Ensemble Forecasts of a Mesoscale Convective Vortex and Associated Severe Weather Environment  

Science Conference Proceedings (OSTI)

An analysis of a regional severe weather outbreak that was related to a mesoscale convective vortex (MCV) is performed. The MCV-spawning mesoscale convection system (MCS) formed in northwest Kansas along the southern periphery of a large cutoff ...

Adam J. Clark; William A. Gallus Jr.; Ming Xue; Fanyou Kong

2010-08-01T23:59:59.000Z

132

ARM - Midlatitude Continental Convective Clouds  

Science Conference Proceedings (OSTI)

Convective processes play a critical role in the Earth's energy balance through the redistribution of heat and moisture in the atmosphere and their link to the hydrological cycle. Accurate representation of convective processes in numerical models is vital towards improving current and future simulations of Earths climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales important to convective processes and therefore must turn to parameterization schemes to represent these processes. In turn, parameterization schemes in cloud-resolving models need to be evaluated for their generality and application to a variety of atmospheric conditions. Data from field campaigns with appropriate forcing descriptors have been traditionally used by modelers for evaluating and improving parameterization schemes.

Mike Jensen; Mary Jane Bartholomew; Anthony Del Genio; Scott Giangrande; Pavlos Kollias

2012-01-19T23:59:59.000Z

133

ARM - Midlatitude Continental Convective Clouds  

DOE Data Explorer (OSTI)

Convective processes play a critical role in the Earth's energy balance through the redistribution of heat and moisture in the atmosphere and their link to the hydrological cycle. Accurate representation of convective processes in numerical models is vital towards improving current and future simulations of Earths climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales important to convective processes and therefore must turn to parameterization schemes to represent these processes. In turn, parameterization schemes in cloud-resolving models need to be evaluated for their generality and application to a variety of atmospheric conditions. Data from field campaigns with appropriate forcing descriptors have been traditionally used by modelers for evaluating and improving parameterization schemes.

Mike Jensen; Mary Jane Bartholomew; Anthony Del Genio; Scott Giangrande; Pavlos Kollias

134

Method of recovering sulfur from the hydrogen sulfide contained in coke oven gases  

SciTech Connect

Ammonia and hydrogen sulfide are washed out of the coke oven gas and stripped from the wash liquor in the form of gases and fumes or vapors. The ammonia is decomposed in a nickel catalyzer and a small part of the decomposition gases is supplied directly to a combustion furnace, while the larger part of the combustion gases is first cooled and freed from condensate, and only then supplied to the combustion furnace. In the combustion furnace, the proportion of H/sub 2/S/SO/sub 2/ needed for the Claus process is adjusted by a partial combustion of the decomposition gases. The gases from the combustion furnace are then processed in the Claus plant to sulfur.

Laufhutte, D.

1985-04-30T23:59:59.000Z

135

Summing up of discussion on improvement trends in coke-oven gas purification flowsheets  

SciTech Connect

Reference is made to a previously published article that included flowsheets for purification of coke-oven gas. It is concluded that the flowsheets for a process using arsenic-soda and vacuum-carbonate methods of sulfur removal in which the gas is cooled to 303-308/sup 0/K are seriously in error. Schemes involving minor refrigeration, sulfur removal by the circulating ammonia method and ammonia recovery as ammonia liquor are seen as promising but in need of further improvement. One scheme discussed (the VUKhIN scheme) involves ammonia recovery by the circulating phosphate method and sulfur removal by the circulating ammonia method is seen as a replacement for the minor refrigeration method. Since liquid ammonia consumption in agriculture is continually increasing, schemes that result in production of liquid ammonia rather than ammonia liquor should be seriously considered.

Zemblevskii, K.K.

1983-01-01T23:59:59.000Z

136

Convectively Coupled Waves in a Sheared Environment  

Science Conference Proceedings (OSTI)

A linear stability analysis, about a radiative–convective equilibrium in a sheared environment, on an equatorial beta plane, for a simple multicloud model for organized tropical convection is presented here. Both vertical/baroclinic and ...

Ying Han; Boualem Khouider

2010-09-01T23:59:59.000Z

137

Helicity and Thermal Convection with Shear  

Science Conference Proceedings (OSTI)

The relations between nonlinear energy transport and helicity of the flow are studied through simulations of thermal convection with mean shear. Parallel-plate convection with a rotating mean shear, a linear undirectional shear, a parabolic ...

Wan-Shu Wu; Douglas K. Lilly; Robert M. Kerr

1992-10-01T23:59:59.000Z

138

Predicting the Movement of Mesoscale Convective Complexes  

Science Conference Proceedings (OSTI)

A procedure for operationally predicting the movement of the mesobeta-scale convective elements responsible for the heavy rain in mesocale convective complexes is presented. The procedure is based on the well-known concepts that the motion of ...

S. F. Corfidi; J. H. Meritt; J. M. Fritsch

1996-03-01T23:59:59.000Z

139

Organizational Modes of Midlatitude Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

This paper discusses common modes of mesoscale convective organization. Using 2-km national composite reflectivity data, the authors investigated linear mesoscale convective systems (MCSs) that occurred in the central United States during May ...

Matthew D. Parker; Richard H. Johnson

2000-10-01T23:59:59.000Z

140

Preconditioning Deep Convection with Cumulus Congestus  

Science Conference Proceedings (OSTI)

Recent studies have pushed forward the idea that congestus clouds, through their moistening of the atmosphere, could promote deep convection. On the other hand, older studies have tended to relate convective initiation to the large-scale forcing. ...

Cathy Hohenegger; Bjorn Stevens

2013-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

A Transilient Matrix for Moist Convection  

Science Conference Proceedings (OSTI)

A method is introduced for diagnosing a transilient matrix for moist convection. This transilient matrix quantifies the nonlocal transport of air by convective eddies: for every height z, it gives the distribution of starting heights z? for the ...

David M. Romps; Zhiming Kuang

2011-09-01T23:59:59.000Z

142

Abstract--The paper reviews solutions being explored to face the supply problems faced in the Chilean electricity market oven  

E-Print Network (OSTI)

gas demand in Chile and Argentina, determining the expected behavior of natural gas producers in the Chilean electricity market oven recent years, given unexpected restrictions in natural gas transfers from Argentina. Investment in generation came to a stall, given uncertainties in natural gas supply and the risk

Catholic University of Chile (Universidad Católica de Chile)

143

A MOLTEN SALT NATURAL CONVECTION REACTOR SYSTEM  

SciTech Connect

Fuel-salt volumes external to the core of a molten-salt reactor are calculated for a system in which the fuel salt circulates through the core and primary exchanger by free convection. In the calculation of these volumes, the exchanger heights above the core top range from 5 to 20 ft. Coolants considered for the primary exchanger are a second molten salt and helium. External fuel holdup is found to be the same with either coolant. Two sets of terminal temperatures are selected for the helium. The first combination permits steam generation at 850 psia, 900 deg F. The second set is selected for a closed gas turbine cycle with an 1100 deg F turbine inlet temperature. Specific power (thermal kw/kg 235) is found to be about 900 Mv/kg, based on initial, clean conditions and a 60 Mw (thermal) output. A specific power of 1275 kw/kg is estimated for a forced convection system of the same rating. (auth)

Romie, F.E.; Kinyon, B.W.

1958-02-01T23:59:59.000Z

144

Rayleigh-Benard convection with phase changes in a Galerkin model  

E-Print Network (OSTI)

The transition to turbulence in Rayleigh-Benard convection with phase changes and the resulting convective patterns are studied in a three-dimensional Galerkin model. Our study is focused to the conditionally unstable regime of moist convection in which the stratification is stable for unsaturated air parcels and unstable for saturated parcels. We perform a comprehensive statistical analysis of the transition to convection that samples the dependence of attractors (or fixed points) in the phase space of the model on the dimensionless parameters. Conditionally unstable convection can be initiated either from a fully unsaturated linearly stable equilibrium or a fully saturated linearly unstable equilibrium. Highly localized moist convection can be found in steady state, in oscillating recharge-discharge regime or turbulent in dependence on the aspect ratio and the degree of stable stratification of the unsaturated air. Our phase space analysis predicts parameter ranges for which self-sustained convective regimes in the case of subcritical conditional instability can be observed. The observed regime transitions for moist convection bear some similarities to transitions to turbulence in simple shear flows.

Thomas Weidauer; Olivier Pauluis; Joerg Schumacher

2011-08-29T23:59:59.000Z

145

A transilient matrix for moist convection  

SciTech Connect

A method is introduced for diagnosing a transilient matrix for moist convection. This transilient matrix quantifies the nonlocal transport of air by convective eddies: for every height z, it gives the distribution of starting heights z{prime} for the eddies that arrive at z. In a cloud-resolving simulation of deep convection, the transilient matrix shows that two-thirds of the subcloud air convecting into the free troposphere originates from within 100 m of the surface. This finding clarifies which initial height to use when calculating convective available potential energy from soundings of the tropical troposphere.

Romps, D.; Kuang, Z.

2011-08-15T23:59:59.000Z

146

SOLOX coke-oven gas desulfurization ppm levels -- No toxic waste  

SciTech Connect

For sulfur removal from coke-oven gas, the reduction/oxidation processes such as Stretford are the most effective, capable of removing the H[sub 2]S down to ppm levels. However, these processes have, in the past, suffered from ecological problems with secondary pollutant formation resulting from side reactions with HCN and O[sub 2]. The SOLOX gas desulfurization system is a development of the Stretford process in which the toxic effluent problems are eliminated by installing a salt decomposition process operating according to the liquid-phase hydrolysis principle. In this process, the gaseous hydrolysis products H[sub 2]S, NH[sub 3] and CO[sub 2] are returned to the untreated gas, and the regenerated solution is recycled to the absorption process. The blowdown from the absorption circuit is fed into a tube reactor where the hydrolysis process takes place. The toxic salts react with water, producing as reaction products the gases H[sub 2]S, NH[sub 3] and CO[sub 2], and the nontoxic salt Na[sub 2]SO[sub 4]. From the hydrolysis reactor the liquid stream flows into a fractionating crystallization plant. This plant produces a recycle stream of regenerated absorption solution and a second stream containing most of the Na[sub 2]SO[sub 4]. This second stream comprises the net plant waste and can be disposed of with the excess ammonia liquor or sprayed onto the coal.

Platts, M. (Thyssen Still Otto Technical Services, Pittsburgh, PA (United States)); Tippmer, K. (Thyssen Still Otto Anlagentechnik GmbH, Bochum (Germany))

1994-09-01T23:59:59.000Z

147

ARM - Evaluation Product - Convective Vertical Velocity  

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsConvective Vertical Velocity ProductsConvective Vertical Velocity Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Convective Vertical Velocity 2011.04.25 - 2011.05.23 Site(s) SGP General Description Convective processes play an important role in Earth's energy balance by distributing heat and moisture throughout the atmosphere. In particular, vertical air motions associated with these processes are inherently linked to the life cycle of these convective systems and are therefore directly tied to their energy budget. However, direct measurements of vertical air motions (e.g., in situ aircraft observations) are sparse, making it difficult to compare them with numerical model output, which relies on convective parameterization schemes that have yet to be extensively

148

Innovative coke oven gas cleaning system for retrofit applications. Environmental Monitoring program. Volume 1 - sampling progrom report. Baseline Sampling Program report  

Science Conference Proceedings (OSTI)

Bethlehem Steel Corporation (BSC), in conjunction with the Department of Energy (DOE) is conducting a Clean Coal Technology (CCT) project at its Sparrows Point, Maryland Coke Oven Plant. This innovative coke oven gas cleaning system combines several existing technologies into an integrated system for removing impurities from Coke Oven Gas (COG) to make it an acceptable fuel. DOE provided cost-sharing under a Cooperative Agreement with BSC. This Cooperative Agreement requires BSC to develop and conduct and Environmental Monitoring Plan for the Clean Coal Technology project and to report the status of the EMP on a quarterly basis. It also requires the preparation of a final report on the results of the Baseline Compliance and Supplemental Sampling Programs that are part of the EMP and which were conducted prior to the startup of the innovative coke oven gas cleaning system. This report is the Baseline Sampling Program report.

Stuart, L.M.

1994-05-27T23:59:59.000Z

149

Sensitivity of Convective Cloud Growth to Mesoscale Lifting: A Numerical Analysis of Mesoscale Convective Triggering  

Science Conference Proceedings (OSTI)

Numerical model simulation of mesoscale lifting of the convective environment indicates that the ability of the environment to develop deep moist convection increases as mesoscale lifting increases. Mesoscale lifting produces increases in modeled ...

David A. Matthews; Bernard A. Silverman

1980-07-01T23:59:59.000Z

150

Convective Inhibition as a Predictor of Convection during AVE-SESAME II  

Science Conference Proceedings (OSTI)

The AVE-SESAME 11 data set of 19 April 1979 is examined to determine the thermodynamic conditions prior to the onset of deep convection in western Kansas. The observations indicate that the convective region was characterized locally by ...

Frank P. Colby Jr.

1984-11-01T23:59:59.000Z

151

Convective Evolution and Merger in the FACE Experimental Area: Mesoscale Convection and Boundary Layer Interactions  

Science Conference Proceedings (OSTI)

This paper investigates the interactions between the various scales of motion and, specifically, the inter-actions between convection and the surface boundary layer in the development of a mesoscale convective system within the Florida Area ...

John B. Cunning; Ronald L. Holle; Patrick T. Gannon; Andrew I. Watson

1982-07-01T23:59:59.000Z

152

A Parameter Study of Interactions Between Convective Clouds, the Convective Boundary Layer, and a Forested Surface  

Science Conference Proceedings (OSTI)

A numerical model was developed which included cloud parameterizations, a convective boundary layer, solar and longwave radiation, a soil layer and a parameterized forest layer. The model simulated the growth of the convective boundary layer and ...

Alfred J. Garrett

1982-08-01T23:59:59.000Z

153

Mesoscale Convective Vortices Observed during BAMEX. Part II: Influences on Secondary Deep Convection  

Science Conference Proceedings (OSTI)

Observations from the Bow Echo and Mesoscale Convective Vortex (MCV) Experiment are used to examine the role of the five mesoscale convective vortices described in Part I on heavy precipitation during the daytime heating cycle. Persistent ...

Stanley B. Trier; Christopher A. Davis

2007-06-01T23:59:59.000Z

154

Sensitivity of Forecast Rainfall in a Texas Convective System to Soil Moisture and Convective Parameterization  

Science Conference Proceedings (OSTI)

The impact of soil moisture on the forecast of a small-scale convective system, and sensitivity of results to the convective parameterization used, are investigated through Eta Model simulations (run in an operational-like setting) of a ...

William A. Gallus Jr.; Moti Segal

2000-10-01T23:59:59.000Z

155

Multiscale Convective Overturning in Mesoscale Convective Systems: Reconciling Observations, Simulations, and Theory  

Science Conference Proceedings (OSTI)

An analysis of how parameterized convection interacts with hydrostatic, explicitly resolved precipitation processes to represent multiscale convective overturning in a mesoscale-resolution numerical simulation is presented. Critically important ...

John S. Kain; J. Michael Fritsch

1998-08-01T23:59:59.000Z

156

Interactions between Shallow and Deep Convection under a Finite Departure from Convective Quasi Equilibrium  

Science Conference Proceedings (OSTI)

The present paper presents a simple theory for the transformation of nonprecipitating, shallow convection into precipitating, deep convective clouds. To make the pertinent point a much idealized system is considered, consisting only of shallow and ...

Jun-Ichi Yano; Robert Plant

2012-12-01T23:59:59.000Z

157

Thermodynamic Variability within the Convective Boundary Layer Due to Horizontal Convective Rolls  

Science Conference Proceedings (OSTI)

Data from the Convection and Precipitation/Electrification (CaPE) Experiment conducted during the summer of 1991 are used to examine and quantify the horizontal variability of temperature and moisture within the convective boundary layer (CBL). ...

Tammy M. Weckwerth; James W. Wilson; Roger M. Wakimoto

1996-05-01T23:59:59.000Z

158

Inside the Supernova: A Powerful Convective Engine  

E-Print Network (OSTI)

Condensed Abstract: We present an extensive study of the inception of supernova explosions by following the evolution of the cores of two massive stars (15 Msun and 25 Msun) in two dimensions. Our calculations begin at the onset of core collapse and stop several 100 ms after the bounce, at which time successful explosions of the appropriate magnitude have been obtained. (...) Guided by our numerical results, we have developed a paradigm for the supernova explosion mechanism. We view a supernova as an open cycle thermodynamic engine in which a reservoir of low-entropy matter (the envelope) is thermally coupled and physically connected to a hot bath (the protoneutron star) by a neutrino flux, and by hydrodynamic instabilities. (...) In essence, a Carnot cycle is established in which convection allows out-of-equilibrium heat transfer mediated by neutrinos to drive low entropy matter to higher entropy and therefore extracts mechanical energy from the heat generated by gravitational collapse. We argue that supernova explosions are nearly guaranteed and self-regulated by the high efficiency of the thermodynamic engine. (...) Convection continues to accumulate energy exterior to the neutron star until a successful explosion has occurred. At this time, the envelope is expelled and therefore uncoupled from the heat source (the neutron star) and the energy input ceases. This paradigm does not invoke new or modified physics over previous treatments, but relies on compellingly straightforward thermodynamic arguments. It provides a robust and self-regulated explosion mechanism to power supernovae which is effective under a wide range of physical parameters.

Marc Herant; Willy Benz; W. Raphael Hix; Chris F. Fryer; Stirling Colgate

1994-04-12T23:59:59.000Z

159

Geothermal: Sponsored by OSTI -- Improving Convection Parameterization...  

Office of Scientific and Technical Information (OSTI)

Improving Convection Parameterization Using ARM Observations and NCAR Community Atmosphere Model Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us | Admin...

160

Tropical Pacific impacts of convective momentum ... - Springer  

Science Conference Proceedings (OSTI)

MJO and monsoons, either directly by changing the atmospheric response to convection, or indirectly by altering the background climatology and ENSO. In fact

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Technical Sessions Parameterization of Convective Clouds, Mesoscale...  

NLE Websites -- All DOE Office Websites (Extended Search)

and Convective-Generated Clouds W. R. Cotton Department of Atmospheric Science Colorado State University Fort Collins, CO 80523 This presentation is a summary of research...

162

Soil Water Retention and Relative Permeability for Conditions from Oven-Dry to Full Saturation  

SciTech Connect

Common conceptual models for unsaturated flow often rely on the oversimplified representation of medium pores as a bundle of cylindrical capillaries and assume that the matric potential is attributed to the capillary force only. The adsorptive surface forces are ignored. It is often assumed that aqueous flow is negligible when a soil is near or at the residual water content. These models are successful at high and medium water contents but often give poor results at low water contents. These models do not apply to conditions at which the water content is less than the residual water content. We extend the lower bound of existing water-retention functions and conductivity models from residual water content to the oven-dry condition (i.e., zero water content) by defining a state-dependent, residual-water content for a soil drier than a critical value. Furthermore, a hydraulic conductivity model for smooth uniform spheres was modified by introducing a correction factor to describe the film flow-induced hydraulic conductivity for natural porous media. The total unsaturated hydraulic conductivity is the sum of those due to capillary and film flow. The extended retention and conductivity models were verified measurements. Results show that, when the soil is at high and intermediate water content, there is no difference between the un-extended and the extended models; when the soil is at low water content, the un-extended models overestimate the water content but underestimate the conductivity. The extended models match the retention and conductivity measurements well.

Zhang, Z. F.

2011-11-04T23:59:59.000Z

163

Measurement of Water Vapor Flux Profiles in the Convective Boundary Layer with Lidar and Radar-RASS  

Science Conference Proceedings (OSTI)

A remote-sensing method to retrieve vertical profiles of water vapor flux in the convective boundary layer by using a differential absorption lidar and a radar-radio acoustic sounding system is described. The system's height range presently ...

Christoph Senff; Jens Bösenberg; Gerhard Peters

1994-02-01T23:59:59.000Z

164

The sensitivity of tropical convective precipitation to the direct radiative forcings of black carbon aerosols emitted from major regions  

E-Print Network (OSTI)

Previous works have suggested that the direct radiative forcing (DRF) of black carbon (BC) aerosols are able to force a significant change in tropical convective precipitation ranging from the Pacific and Indian Ocean to ...

Wang, Chien

165

Parameterization of Convective Momentum Transport in Highly Baroclinic Conditions  

Science Conference Proceedings (OSTI)

The organization of convection by vertical shear strongly affects the transport of horizontal momentum, yet the concept of organization has received little attention in convective parameterization. Here the focus is on open-cellular convection in ...

Vanda Grubiši?; Mitchell W. Moncrieff

2000-09-01T23:59:59.000Z

166

Structure of the Atmosphere in Radiative–Convective Equilibrium  

Science Conference Proceedings (OSTI)

To investigate water vapor transport in an atmosphere in radiative–convective equilibrium, a simplified dynamical convection model (DCM) was constructed that explicitly models moist convection and longwave radiation in a gray atmosphere. In the ...

Yoshiharu Iwasa; Yutaka Abe; Hiroshi Tanaka

2002-07-01T23:59:59.000Z

167

Elevated Convection and Castellanus: Ambiguities, Significance, and Questions  

Science Conference Proceedings (OSTI)

The term elevated convection is used to describe convection where the constituent air parcels originate from a layer above the planetary boundary layer. Because elevated convection can produce severe hail, damaging surface wind, and excessive ...

Stephen F. Corfidi; Sarah J. Corfidi; David M. Schultz

2008-12-01T23:59:59.000Z

168

Deep Convection and “First Echoes” within Anvil Precipitation  

Science Conference Proceedings (OSTI)

The development of convective cells within anvil precipitation, in a region of moderate convective activity that might be called a small mesoscale convective system, is described and discussed. The presence of precipitation-sized hydrometeors in ...

Charles A. Knight; L. Jay Miller; William D. Hall

2004-07-01T23:59:59.000Z

169

Convection Initiation and Downburst Experiment (CINDE)  

Science Conference Proceedings (OSTI)

The Convection Initiation and Downburst Experiment (CINDE) was conducted in the Denver, Colorado area from 22 June to 7 August 1987 to study processes leading to the formation of deep convection and the physics of downbursts. A total of 6 Doppler ...

James W. Wilson; James A. Moore; G. Brant Foote; Brooks Martner; Taneil Uttal; James M. Wilczak; Alfred R. Rodi

1988-11-01T23:59:59.000Z

170

Nature versus Nurture in Shallow Convection  

Science Conference Proceedings (OSTI)

Tracers are used in a large-eddy simulation of shallow convection to show that stochastic entrainment (and not cloud-base properties) determines the fate of convecting parcels. The tracers are used to diagnose the correlations between a parcel’s ...

David M. Romps; Zhiming Kuang

2010-05-01T23:59:59.000Z

171

Trials and Tribulations of Ancient Starch Research: An Investigation of Contamination and Earth Ovens at Fort Hood, Texas  

E-Print Network (OSTI)

Historically, earth ovens have been used to provide direct evidence of ancient plant use through the recovery of charred macrobotanical remains and indirectly by means of experimental archaeology and the ethnographic record. Experiments suggest that direct evidence of ancient starch-rich plant use can be obtained through the recovery of starch granules deposited on fire-cracked-rock (FCR) during cooking episodes even in regions where macrobotanical remains are scarcely preserved. Starch contamination, however, can enter into the archaeological record providing “background noise.” Therefore, this study analyzes the results of the Paluxy Sand Geophyte Project to determine if archaeological starch (starch that is both cultural and ancient in origin) can be differentiated from contamination using FCR recovered from heating elements in well-preserved earth ovens at Fort Hood, Texas. FCR, non-cultural rock control samples (RCS), and air control samples (ACS) were processed and analyzed from 27 earth ovens at 6 sites. Contamination control measures were used, including the use of a clean bench, powder-free latex gloves, washing samples prior to processing, spot sampling, and comparisons between starch granule assemblages recovered from FCR and control samples. Laboratory and field equipment were processed and analyzed for contamination. Only one feature (Feature 4 from 41CV984) yielded starch granules that are unambiguously archaeological in origin, rather than the result of contamination, whereas starch assemblages from the other sites could be archaeological or contamination in origin. Small sample sizes, differential preservation, and/or the cooking of non-starch-rich plants could account for the lack of differences between FCR and RCS samples. Finally, maize (Zea mays) starch granules were recovered from all sample types suggesting that maize starch, most likely from “powder-free” gloves and air-fall is a significant source of starch contamination.

Laurence, Andrew

2013-05-01T23:59:59.000Z

172

Innovative coke oven gas cleaning system for retrofit applications. Quarterly environmental monitoring report No. 1, January 1, 1991--June 30, 1991  

DOE Green Energy (OSTI)

The coke plant at the Sparrows Point Plant consist of three coke oven batteries and two coal chemical plants. The by-product coke oven gas (COG) consists primarily of hydrogen, methane, carbon monoxide, nitrogen and contaminants consisting of tars, light oils (benzene, toluene, and xylene) hydrogen sulfide, ammonia, water vapor and other hydrocarbons. This raw coke oven gas needs to be cleaned of most of its contaminants before it can be used as a fuel at other operations at the Sparrows Point Plant. In response to environmental concerns, BSC decided to replace much of the existing coke oven gas treatment facilities in the two coal chemical Plants (A and B) with a group of technologies consisting of: Secondary Cooling of the Coke oven Gas; Hydrogen Sulfide Removal; Ammonia Removal; Deacification of Acid Gases Removed; Ammonia Distillation and Destruction; and, Sulfur Recovery. This combination of technologies will replace the existing ammonia removal system, the final coolers, hydrogen sulfide removal system and the sulfur recovery system. The existing wastewater treatment, tar recovery and one of the three light oil recovery systems will continue to be used to support the new innovative combination of COG treatment technologies.

Not Available

1992-08-24T23:59:59.000Z

173

Convective heat transfer inside passive solar buildings  

DOE Green Energy (OSTI)

Natural convection between spaces in a building can play a major role in energy transfer. Two situations are investigated: convection through a single doorway into a remote room, and a convective loop in a two-story house with a south sunspace where a north stairway serves as the return path. A doorway-sizing equation is given for the single-door case. Detailed data are given from the monitoring of airflow in one two-story house and summary data are given for five others. Observations on the nature of the airflow and design guidelines are presented.

Jones, R.W.; Balcomb, J.D.; Yamaguchi, K.

1983-01-01T23:59:59.000Z

174

Prandtl Number Dependent Natural Convection with Internal Heat Sources  

SciTech Connect

Natural convection plays an important role in determining the thermal load from debris accumulated in the reactor vessel lower head during a severe accident. Recently, attention is being paid to the feasibility of external vessel flooding as a severe accident management strategy and to the phenomena affecting the success path for retaining the molten core material inside the vessel. The heat transfer inside the molten core material can be characterized by the strong buoyancy-induced flows resulting from internal heating due to decay of fission products. The thermo-fluid dynamic characteristics of such flow depend strongly on the thermal boundary conditions. The spatial and temporal variation of heat flux on the pool wall boundaries and the pool superheat are mainly characterized by the natural convection flow inside the molten pool. In general, the natural convection heat transfer phenomena involving the internal heat generation are represented by the modified Rayleigh number (Ra’), which quantifies the internal heat source and hence the strength of the buoyancy force. In this study, tests were conducted in a rectangular section 250 mm high, 500 mm long and 160 mm wide. Twenty-four T-type thermocouples were installed in the test section to measure temperatures. Four T-type thermocouples were used to measure the boundary temperatures. The thermocouples were placed in designated locations after calibration. A direct heating method was adopted in this test to simulate the uniform heat generation. The experiments covered a range of Ra' between 1.5x106 and 7.42x1015 and the Prandtl number (Pr) between 0.7 and 6.5. Tests were conducted with water and air as simulant. The upper and lower boundary conditions were maintained uniform. The results demonstrated feasibility of the direct heating method to simulate uniform volumetric heat generation. Particular attentions were paid to the effect of Pr on natural convection heat transfer within the rectangular pool.

Kang Hee Lee; Seung Dong Lee; Kune Y. Suh; Joy L. Rempe; Fan-Bill Cheung; Sang B. Kim

2004-06-01T23:59:59.000Z

175

A General Framework for Convective Trigger Functions  

Science Conference Proceedings (OSTI)

A general framework for the trigger function used in convective parameterization routines in mesoscale models is proposed. The framework is based on the diagnosis of the accessibility of potential buoyant energy. Specifically, the trigger ...

Robert F. Rogers; J. M. Fritsch

1996-11-01T23:59:59.000Z

176

Climatic Regimes of Tropical Convection and Rainfall  

Science Conference Proceedings (OSTI)

Annual distribution and phase propagation of tropical convection are delineated using harmonic and amplitude-phase characteristics analysis of climatological pentad mean outgoing longwave radiation and monthly frequencies of highly reflective ...

Bin Wang

1994-07-01T23:59:59.000Z

177

Doppler Radar Sampling Limitations in Convective Storms  

Science Conference Proceedings (OSTI)

Vertical air motion data from a T-28 aircraft were filtered and sampled to simulate Doppler radar measurements. The results suggest that multiple Doppler radar analyses are subject to potentially large spatial aliasing errors in deep convection ...

R. E. Carbone; M. J. Carpenter; C. D. Burghart

1985-09-01T23:59:59.000Z

178

Tracer dispersion in the turbulent convective layer  

Science Conference Proceedings (OSTI)

Experimental results for passive tracer dispersion in the turbulent surface layer under convective conditions are presented. In this case, the dispersion of tracer particles is determined by the interplay of two mechanisms: buoyancy and advection. ...

Alex Skvortsov; Milan Jamriska; Timothy C. DuBois

179

Convective Squalls over the Eastern Equatorial Atlantic  

Science Conference Proceedings (OSTI)

The Congo Basin and the adjacent equatorial eastern Atlantic are among the most active regions of the world in terms of intense deep moist convection, leading to frequent lightning and severe squalls. Studying the dynamics and climatology of this ...

Florian Berkes; Peter Knippertz; Douglas J. Parker; Gus Jeans; Valérie Quiniou-Ramus

2012-06-01T23:59:59.000Z

180

A Composite Model of Mesoscale Convective Complexes  

Science Conference Proceedings (OSTI)

A composite analysis technique is used to investigate the evolution of mesoscale features of mesoscale convective complexes (MCCs). The early stage of the MCC lifecycle is characterized by convergence, vertical motion and heating being centered ...

William R. Cotton; Ming-Sen Lin; Ray L. McAnelly; Craig J. Tremback

1989-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Estimation of Convective Rainfall from Lightning Observations  

Science Conference Proceedings (OSTI)

The objective of this study is to develop a technique to use lightning observations for estimating convective rainfall. A framework for rainfall estimation is developed in which key elements are 1) the rainfall–lightning ratio, that is, the ...

Alberto Tapia; James A. Smith; Michael Dixon

1998-11-01T23:59:59.000Z

182

Convective Systems of the North Australian Monsoon  

Science Conference Proceedings (OSTI)

The climatology of convection over northern Australia and the surrounding oceans, based on six wet seasons (September–April), is derived from the Japanese Meteorological Agency Geostationary Meteorological Satellite-5 (GMS-5) IR1 channel for the ...

Mick Pope; Christian Jakob; Michael J. Reeder

2008-10-01T23:59:59.000Z

183

Mesoscale Convective Complexes over Southern Africa  

Science Conference Proceedings (OSTI)

The maximum spatial correlation technique (MASCOTTE) is an objective and automated method developed to simultaneously determine both the structural properties and evolution (tracking) of cloud shields of convective systems. Originally designed to ...

R. C. Blamey; C. J. C. Reason

2012-01-01T23:59:59.000Z

184

Soil Moisture Impacts on Convective Margins  

Science Conference Proceedings (OSTI)

An idealized prototype for the location of the margins of tropical land region convection zones is extended to incorporate the effects of soil moisture and associated evaporation. The effect of evaporation, integrated over the inflow trajectory ...

Benjamin R. Lintner; J. David Neelin

2009-08-01T23:59:59.000Z

185

Radiation Impacts on Conditionally Unstable Moist Convection  

Science Conference Proceedings (OSTI)

The present work analyzes the impacts of radiative cooling in three-dimensional high-resolution direct numerical simulations of moist Rayleigh–Bénard convection. An atmospheric slab is destabilized by imposing a warm, moist lower boundary and a ...

Olivier Pauluis; Jörg Schumacher

2013-04-01T23:59:59.000Z

186

Moist Convection at a Surface Cold Front  

Science Conference Proceedings (OSTI)

The motion of a surface cold front in an environment that is unstable to moist convection is studied with the aid ofboth hydrostatic and nonhydrostatic two-dimensional models. Simulations with the hydrostatic model essentially extend the work ...

N. Andrew Crook

1987-12-01T23:59:59.000Z

187

Rotating Convection Driven by Differential Bottom Heating  

Science Conference Proceedings (OSTI)

Convection experiments were carried out in a rectangular tank as a model of oceanic meridional overturning circulation. The objective was finding a relation between the meridional heat flux and thermal forcing. To make the meridional heat flux ...

Young-Gyu Park; J. A. Whitehead

1999-06-01T23:59:59.000Z

188

Urban Aerosol Impacts on Downwind Convective Storms  

Science Conference Proceedings (OSTI)

The impacts of urban-enhanced aerosol concentrations on convective storm development and precipitation over and downwind of St. Louis, Missouri, are investigated. This is achieved through the use of a cloud-resolving mesoscale model, in which ...

Susan C. van den Heever; William R. Cotton

2007-06-01T23:59:59.000Z

189

Measurement of Convective Entrainment Using Lagrangian Particles  

Science Conference Proceedings (OSTI)

Lagrangian particle tracking is used in a large-eddy simulation to study an individual cumulus congestus. This allows for the direct measurement of the convective entrainment rate and of the residence times of entrained parcels within the cloud. ...

Kyongmin Yeo; David M. Romps

2013-01-01T23:59:59.000Z

190

Resolving Convection in a Global Hypohydrostatic Model  

Science Conference Proceedings (OSTI)

Convection cannot be explicitly resolved in general circulation models given their typical grid size of 50 km or larger. However, by multiplying the vertical acceleration in the equation of motion by a constant larger than unity, the horizontal ...

S. T. Garner; D. M. W. Frierson; I. M. Held; O. Pauluis; G. K. Vallis

2007-06-01T23:59:59.000Z

191

Convective Control of ENSO Simulated in MIROC  

Science Conference Proceedings (OSTI)

The high sensitivity of the El Niño–Southern Oscillation (ENSO) to cumulus convection is examined by means of a series of climate simulations using an updated version of the Model for Interdisciplinary Research on Climate (MIROC), called MIROC5. ...

Masahiro Watanabe; Minoru Chikira; Yukiko Imada; Masahide Kimoto

2011-01-01T23:59:59.000Z

192

Nested-Model Simulation of Moist Convection: The Impact of Coarse-Grid Parameterized Convection on Fine-Grid Resolved Convection  

Science Conference Proceedings (OSTI)

Future-generation, operational, weather prediction systems will likely include storm-scale, limited-area models that will explicitly resolve convective precipitation. However, the high-resolution convection-resolving grids will need to be ...

Thomas T. Warner; Hsiao-Ming Hsu

2000-07-01T23:59:59.000Z

193

Buoyancy of Convective Vertical Motions in the Inner Core of Intense Hurricanes. Part I: General Statistics  

Science Conference Proceedings (OSTI)

The buoyancy of hurricane convective vertical motions is studied using aircraft data from 175 radial legs collected in 14 intense hurricanes at four altitudes ranging from 1.5 to 5.5 km. The data of each leg are initially filtered to separate ...

Matthew D. Eastin; William M. Gray; Peter G. Black

2005-01-01T23:59:59.000Z

194

Influence of technological factors on statics of hydrogen sulfide absorption from coke-oven gas by the ammonia process  

SciTech Connect

The basic technological factors that determine the effectiveness of hydrogen sulfide absorption from coke-oven gas by the cyclic ammonia process are the initial H/sub 2/S content of the gas, the degree of purification, the absorption temperature and the NH/sub 3/ and CO/sub 2/ contents of the absorbent solution. The effects of these factors on the statics of hydrogen sulfide absorption are studied. The investigation is based on the phase-equilibrium distributions of components in the absorption-desorption gas-cleaning cycle. The mathematical model is presented which includes the solution of a system of chemical equilibrium equations for reactions in the solution, material balances, and electrical neutrality. 4 references, 5 figures, 1 table.

Nazarov, V.G.; Kamennykh, B.M.; Rus'yanov, N.D.

1983-01-01T23:59:59.000Z

195

Modeling Study of a Tropical Squall-Type Convective Line  

Science Conference Proceedings (OSTI)

A multidimensional and time-dependent cloud scale model is used to investigate the dynamic and micro-physical processes associated with convective and stratiform regions within a tropical squall-type convective line. The evolution of the total ...

Wei-Kuo Tao; Joanne Simpson

1989-01-01T23:59:59.000Z

196

Synoptic Environments Associated with the Training of Convective Cells  

Science Conference Proceedings (OSTI)

Many studies have been done on synoptically forced systems and heavy rainfall, but little research has gone into the forecasting of training convective storms specifically in a synoptically forced environment. Training convective storms are ...

Ryan P. Aylward; Jamie L. Dyer

2010-04-01T23:59:59.000Z

197

Physics of Greenhouse Effect and Convection in Warm Oceans  

Science Conference Proceedings (OSTI)

Sea surface temperature (SST) in roughly 50% of the tropical Pacific Ocean is warm enough (SST > 300 K) to permit deep convection. This paper examines the effects of deep convection on the climatological mean vertical distributions of water vapor ...

A. K. Inamdar; V. Ramanathan

1994-05-01T23:59:59.000Z

198

Resonant Response of Deep Convection to Surface Hot Spots  

Science Conference Proceedings (OSTI)

Observations show substantial variations of the intensity of tropical and/or summertime deep convection on land that are not explained by standard measures of convective instability. One feature that distinguishes land surfaces is their ...

F. J. Robinson; S. C. Sherwood; Y. Li

2008-01-01T23:59:59.000Z

199

Behavior of Turbulence Statistics in the Convective Boundary Layer  

Science Conference Proceedings (OSTI)

Velocity variances in the convective boundary layer are examined using data derived in PBL experiments over land (Minnesota) and ocean (the Coral Sea) supported by data from the Kansas study of the surface boundary layer. In the freely convective ...

B. B. Hicks

1985-06-01T23:59:59.000Z

200

Scalable adaptive mantle convection simulation on petascale supercomputers  

Science Conference Proceedings (OSTI)

Mantle convection is the principal control on the thermal and geological evolution of the Earth. Mantle convection modeling involves solution of the mass, momentum, and energy equations for a viscous, creeping, incompressible non-Newtonian fluid at high ...

Carsten Burstedde; Omar Ghattas; Michael Gurnis; Georg Stadler; Eh Tan; Tiankai Tu; Lucas C. Wilcox; Shijie Zhong

2008-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

A Theory for Long-Lived Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

It is proposed that certain long-lived mesoscale convective systems maintain themselves through an interaction between quasi-balanced vertical motions and the diabatic effects of moist convection. Latent heat release, evaporation and melting of ...

D. J. Raymond; H. Jiang

1990-12-01T23:59:59.000Z

202

Linear Stratospheric Gravity Waves above Convective Thermal Forcing  

Science Conference Proceedings (OSTI)

The spectra of linear gravity waves generated by a time-varying tropospheric thermal forcing representing organized convection are compared to the spectra of stratospheric gravity waves generated by organized convection in a fully nonlinear two-...

Rajul E. Pandya; M. Joan Alexander

1999-07-01T23:59:59.000Z

203

Thermodynamic and Circulation Characteristics, of Winter Monsoon Tropical Mesoscale Convection  

Science Conference Proceedings (OSTI)

During the December 1978 field phase of the International Winter Monsoon Experiment (Winter MONEX), a regular diurnal cycle of deep convective activity occurred over the South China Sea immediately to the north of Borneo. The convection was ...

Richad H. Johnson; Donald C. Kriete

1982-12-01T23:59:59.000Z

204

Mesoscale Convective Complexes over the United States during 1983  

Science Conference Proceedings (OSTI)

Enhanced infrared satellite imagery is used to document the occurrence of mesoscale convective complexes over the United States during 1983. Thirty large convective systems are identified that display satellite-observable characteristics which ...

D. M. Rodgers; M. J. Magnano; J. H. Arns

1985-05-01T23:59:59.000Z

205

Propagating and Standing Components of the Intraseasonal Oscillationin Tropical Convection  

Science Conference Proceedings (OSTI)

Two questions related to the intraseasonal variability of tropical convection and circulation remain controversial. 1) To what degree is the convective component of the Madden–Julian oscillation (MJO) a standing oscillation? 2) Is the eastward ...

Chidong Zhang; Harry H. Hendon

1997-03-01T23:59:59.000Z

206

Multiscale Convective Organization and the YOTC Virtual Global Field Campaign  

Science Conference Proceedings (OSTI)

The Year of Tropical Convection (YOTC) project recognizes that major improvements are needed in how the tropics are represented in climate models. Tropical convection is organized into multiscale precipitation systems with an underlying chaotic order. ...

Mitchell W. Moncrieff; Duane E. Waliser; Martin J. Miller; Melvyn A. Shapiro; Ghassem R. Asrar; James Caughey

2012-08-01T23:59:59.000Z

207

Convection in TOGA COARE: Horizontal Scale, Morphology, and Rainfall Production  

Science Conference Proceedings (OSTI)

The occurrence frequency and rainfall production of mesoscale convective systems (MCSs) relative to smaller groups of convective clouds over the tropical oceans is not well known. Eighty days of shipboard radar data collected during the recent ...

Thomas M. Rickenbach; Steven A. Rutledge

1998-09-01T23:59:59.000Z

208

Effects of Convection Cell Geometry on Simulated Tornadoes  

Science Conference Proceedings (OSTI)

Experimental data and theory suggest that certain convection cell scale factors must be specified for correct interpretation of tornado simulations. The most important nondimensional number appears to be the ratio of convection cell depth (...

Eugene M. Wilkins; Chris J. Diamond

1987-01-01T23:59:59.000Z

209

Structures and Dynamics of Quasi-2D Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

Recently, three distinct archetypes for midlatitude linear mesoscale convective systems (MCSs) have been identified. This article focuses on the fundamentals of two of these archetypes: convective lines with trailing stratiform (TS) precipitation ...

Matthew D. Parker; Richard H. Johnson

2004-03-01T23:59:59.000Z

210

Baroclinic Transition of a Long-Lived Mesoscale Convective Vortex  

Science Conference Proceedings (OSTI)

The period 5–15 June 2003, during the field phase of the Bow Echo and Mesoscale Convective Vortex (MCV) Experiment (BAMEX), was noteworthy for the wide variety of mesoscale convective systems (MCSs) that occurred. Of particular interest was a ...

Thomas J. Galarneau Jr.; Lance F. Bosart; Christopher A. Davis; Ron McTaggart-Cowan

2009-02-01T23:59:59.000Z

211

Parameterized Updraft Mass Flux as a Predictor of Convective Intensity  

Science Conference Proceedings (OSTI)

Parameterized updraft mass flux, available as a unique predictive field from the Kain–Fritsch (KF) convective parameterization, is presented as a potentially valuable predictor of convective intensity. The KF scheme is described in some detail, ...

John S. Kain; Michael E. Baldwin; Steven J. Weiss

2003-02-01T23:59:59.000Z

212

Thermodynamic Properties of Mesoscale Convective Systems Observed during BAMEX  

Science Conference Proceedings (OSTI)

Dropsonde observations from the Bow Echo and Mesoscale Convective Vortex Experiment (BAMEX) are used to document the spatiotemporal variability of temperature, moisture, and wind within mesoscale convective systems (MCSs). Onion-type sounding ...

James Correia Jr.; Raymond W. Arritt

2008-11-01T23:59:59.000Z

213

Convectively Driven Turbulent Mixing in the Upper Ocean  

Science Conference Proceedings (OSTI)

Two experiments were performed to study the characteristics of turbulence in convective mixed layers in the upper Ocean. In the first, a diurnal convective mixed layer developed in the Bahamas under the influence of the cycle of daytime solar ...

T. J. Shay; M. C. Gregg

1986-11-01T23:59:59.000Z

214

Mesoscale Convective Complexes over the United States during 1982  

Science Conference Proceedings (OSTI)

An important class of convective weather system, the mesoscale convective complex (MCC), presents many challenges and problems to both the research and operational communities. In addition, thew very large and long-lived thunderstorm systems have ...

D. M. Rodgers; K. W. Howard; E. C. Johnston

1983-12-01T23:59:59.000Z

215

Simulation of Tropical Convective Systems. Part I: A Cumulus Parameterization  

Science Conference Proceedings (OSTI)

A new cumulus parametefization is developed for ffse in mesoscale model simulations of precipitating convective systems. It is designed to estimate convective properties using a cloud model that interacts with the mesoscale model in a physically ...

William M. Frank; Charles Cohen

1987-12-01T23:59:59.000Z

216

Assessing the Vertical Distribution of Convective Available Potential Energy  

Science Conference Proceedings (OSTI)

Comparisons of convective available potential energy (CAPE) with standard instability indices for evaluating the convective potential of the atmosphere such as the lifted index (LI) reveal only moderate correlations. This is because the LI is a ...

David O. Blanchard

1998-09-01T23:59:59.000Z

217

Hydrography of the Labrador Sea during Active Convection  

Science Conference Proceedings (OSTI)

The hydrographic structure of the Labrador Sea during wintertime convection is described. The cruise, part of the Deep Convection Experiment, took place in February–March 1997 amidst an extended period of strong forcing in an otherwise moderate ...

Robert S. Pickart; Daniel J. Torres; R. Allyn Clarke

2002-02-01T23:59:59.000Z

218

Convective Momentum Transport over the Tropical Pacific: Budget Estimates  

Science Conference Proceedings (OSTI)

ECMWF and NCEP–NCAR reanalyses are used to calculate convective momentum transport (CMT) as a momentum budget residual over several tropical oceanic convective regions, including the TOGA COARE Intensive Flux Array (IFA). Sources of uncertainty ...

Matthew T. Carr; Christopher S. Bretherton

2001-07-01T23:59:59.000Z

219

Cycles and Propagation of Deep Convection over Equatorial Africa  

Science Conference Proceedings (OSTI)

Long-term statistics of organized convection are vital to improved understanding of the hydrologic cycle at various scales. Satellite observations are used to understand the timing, duration, and frequency of deep convection in equatorial Africa, ...

Arlene G. Laing; Richard E. Carbone; Vincenzo Levizzani

2011-09-01T23:59:59.000Z

220

Sensitivity of Monthly Convective Precipitation to Environmental Conditions  

Science Conference Proceedings (OSTI)

Identifying dynamical and physical mechanisms controlling variability of convective precipitation is critical for predicting intraseasonal and longer-term changes in warm-season precipitation and convectively driven large-scale circulations. On a ...

Boksoon Myoung; John W. Nielsen-Gammon

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Implicit Versus Explicit Convective Heating in Numerical Weather Prediction Models  

Science Conference Proceedings (OSTI)

The ability of several explicit formulations of convective heating to predict the precipitation associated with a mesoscale convective complex was compared to that of a cumulus parameterization on a ½ deg latitude-longitude mesh. In the explicit ...

John Molinari; Michael Dudek

1986-10-01T23:59:59.000Z

222

A Model to Determine Open or Closed Cellular Convection  

Science Conference Proceedings (OSTI)

A simple mechanism is proposed to help explain the observed presence in the atmosphere of open or closed cellular convection. If convection is produced by cooling concentrated near the top of the cloud layer, as in radiative cooling of stratus ...

H. Mark Helfand; Eugenia Kalnay

1983-03-01T23:59:59.000Z

223

Cloud-to-Ground Lightning Activity in Mesoscale Convective Complexes  

Science Conference Proceedings (OSTI)

A study of cloud-to-ground lightning activity attending an important subclass of mesoscale convective weather systems called the mesoscale convective complex shows that groun discharge flash rates in excess of 1000 h?1 can be sustained on average ...

S. J. Goodman; D. R. MacGorman

1986-12-01T23:59:59.000Z

224

Aircraft Investigation of Mesoscale Cellular Convection During AMTEX 75  

Science Conference Proceedings (OSTI)

The 1 s data set collected by the NCAR Electra research aircraft in the presence of closed mesoscale cellular convection (MCC) has been examined for the purpose of determining the convective wind field and horizontal profiles of temperature and ...

Jeffry Rothermel; Ernest M. Agee

1980-05-01T23:59:59.000Z

225

Factors Governing the Total Rainfall Yield from Continental Convective Clouds  

Science Conference Proceedings (OSTI)

Several important factors that govern the total rainfall from continental convective clouds were investigated by tracking thousands of convective cells in Israel and South Africa. The rainfall volume yield (Rvol) of the individual cells that ...

Daniel Rosenfeld; Abraham Gagin

1989-10-01T23:59:59.000Z

226

Nonlinear Effects on Convectively Forced Two-Dimensional Mesoscale Flows  

Science Conference Proceedings (OSTI)

One of the important problems in mesoscale atmospheric dynamics is how the atmosphere responds to convective heating or cooling. Here, the authors examine nonlinear effects on convectively forced mesoscale flows in the context of the nonlinear ...

Ji-Young Han; Jong-Jin Baik

2012-11-01T23:59:59.000Z

227

Convective Contribution to the Genesis of Hurricane Ophelia (2005)  

Science Conference Proceedings (OSTI)

The convection occurring in the tropical depression that became Hurricane Ophelia (2005) was investigated just prior to tropical storm formation. Doppler radar showed a deep, wide, intense convective cell of a type that has been previously ...

Robert A. Houze Jr.; Wen-Chau Lee; Michael M. Bell

2009-09-01T23:59:59.000Z

228

Balanced Dynamics of Mesoscale Vortices Produced in Simulated Convective Systems  

Science Conference Proceedings (OSTI)

Long-lived, mesoscale convective systems are known to occasionally produce mesoscale convective vortices (MCVs) in the lower to middle troposphere with horizontal scales averaging 100–200 km. The formation of MCVs is investigated using fully ...

Christopher A. Davis; Morris L. Weisman

1994-07-01T23:59:59.000Z

229

Regulation of Moist Convection over the West Pacific Warm Pool  

Science Conference Proceedings (OSTI)

The mechanisms that regulate moist convection over the warm tropical oceans are not well understood. One school of thought holds that convection is caused by the convergence of moisture, which in turn is produced by an independent dynamical ...

David J. Raymond

1995-11-01T23:59:59.000Z

230

A Convective Line with Leading Stratiform Precipitation from BAMEX  

Science Conference Proceedings (OSTI)

On 31 May 2003, a front-fed convective line with leading stratiform precipitation (FFLS) was observed during the Bow Echo and Mesoscale Convective Vortex Experiment (BAMEX). The high-resolution BAMEX measurements provided one of the first ...

Brandon A. Storm; Matthew D. Parker; David P. Jorgensen

2007-05-01T23:59:59.000Z

231

Simulations of stellar convection with CO5BOLD  

Science Conference Proceedings (OSTI)

High-resolution images of the solar surface show a granulation pattern of hot rising and cooler downward-sinking material - the top of the deep-reaching solar convection zone. Convection plays a role for the thermal structure of the solar interior and ... Keywords: Numerical simulations, Radiation (magneto)hydrodynamics, Stellar surface convection

B. Freytag; M. Steffen; H. -G. Ludwig; S. Wedemeyer-Böhm; W. Schaffenberger; O. Steiner

2012-02-01T23:59:59.000Z

232

Heat Flux Partitioning in Open-Ocean Convection  

Science Conference Proceedings (OSTI)

Cold air blowing out over a warm ocean leads to convection over an isolated region of the ocean basin. This phenomenon, known as open-ocean convection, is often simulated by convective forcing from a circular disk much smaller than the dimension ...

David Brickman

1995-11-01T23:59:59.000Z

233

Comparison between Low-Flash and Non-Lightning-Producing Convective Areas within a Mature Mesoscale Convective System  

Science Conference Proceedings (OSTI)

Two small multicellular convective areas within a larger mesoscale convective system that occurred on 20 June 2004 were examined to assess vertical motion, radar reflectivity, and dual-polarimetric signatures between flash and non-flash-producing ...

Jennifer L. Palucki; Michael I. Biggerstaff; Donald R. MacGorman; Terry Schuur

2011-08-01T23:59:59.000Z

234

The Convective Instability Pathway to Warm Season Drought in Texas. Part II: Free-Tropospheric Modulation of Convective Inhibition  

Science Conference Proceedings (OSTI)

This study is concerned with the modulation by convective instability of summertime precipitation in Texas as a mechanism for maintaining or enhancing drought. The important role of convective inhibition (CIN), its dependence on the temperature ...

Boksoon Myoung; John W. Nielsen-Gammon

2010-09-01T23:59:59.000Z

235

Numerical Prediction of Convectively Driven Mesoscale Pressure Systems. Part I: Convective Parameterization  

Science Conference Proceedings (OSTI)

A parameterization formulation for incorporating the effects of midlatitude deep convection into mesoscale-numerical models is presented. The formulation is based on the hypothesis that the buoyant energy available to a parcel, in combination ...

J. M. Fritsch; C. F. Chappell

1980-08-01T23:59:59.000Z

236

Precipitation and Kinematic Structure of an Oceanic Mesoscale Convective System. Part I: Convective Line Structure  

Science Conference Proceedings (OSTI)

The precipitation, thermodynamic, and kinematic structure of an oceanic mesoscale convective system is studied using airborne Doppler and in situ (flight-level) data collected by the NOAA P-3 aircraft. The system, a well-organized, stationary, ...

David P. Jorgensen; Margaret A. LeMone; Ben Jong-Dao Jou

1991-11-01T23:59:59.000Z

237

Aerosol Indirect Effects on Tropical Convection Characteristics under Conditions of Radiative–Convective Equilibrium  

Science Conference Proceedings (OSTI)

The impacts of enhanced aerosol concentrations such as those associated with dust intrusions on the trimodal distribution of tropical convection have been investigated through the use of large-domain (10 000 grid points), fine-resolution (1 km), ...

Susan C. van den Heever; Graeme L. Stephens; Norman B. Wood

2011-04-01T23:59:59.000Z

238

Coupling of Convective Momentum Transport with Convective Heating in Global Climate Simulations  

Science Conference Proceedings (OSTI)

The effects of convective momentum transport (CMT) on global climate simulations are examined in this study. Comparison between two sets of 20-yr (1979–98) integration using the NCAR Community Climate Model version 3 (CCM3) illustrates that the ...

Xiaoqing Wu; Liping Deng; Xiaoliang Song; Guang Jun Zhang

2007-04-01T23:59:59.000Z

239

Response of Tropical Deep Convection to Localized Heating Perturbations: Implications for Aerosol-Induced Convective Invigoration  

Science Conference Proceedings (OSTI)

A cloud-system-resolving model is used to investigate the effects of localized heating/cooling perturbations on tropical deep convection, in the context of the aerosol “invigoration effect.” This effect supposes that a reduction of droplet ...

Hugh Morrison; Wojciech W. Grabowski

2013-11-01T23:59:59.000Z

240

Unsteady, Turbulent Convection into a Rotating, Linearly Stratified Fluid: Modeling Deep Ocean Convection  

Science Conference Proceedings (OSTI)

A laboratory experiment has been constructed to Model the deep convective processes in a stratified ocean driven by the energetic cooling at the ocean surface. For convenience in the laboratory the authors have examined the analogous but inverted ...

M. J. Coates; G. N. Ivey; J. R. Taylor

1995-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

A Convective Cell in a Hurricane Rainband  

Science Conference Proceedings (OSTI)

On 10 October 1983 the two NOAA WP-3D aircraft completed a mission designed to provide airborne Doppler radar data for a convective cell embedded in a weak rainband on the trailing side of Hurricane Raymond. Comparisons of the wind field produced ...

G. M. Barnes; J. F. Gamache; M. A. LeMone; G. J. Stossmeister

1991-03-01T23:59:59.000Z

242

A Convective Transport Theory for Surface Fluxes  

Science Conference Proceedings (OSTI)

For a boundary layer in free convection where turbulent thermal structures communicate information between the surface and the interior of the mixed layer, it is hypothesized that the surface momentum flux can be parameterized by u*2 = bDwBMML, ...

Roland B. Stull

1994-01-01T23:59:59.000Z

243

Convective Building of a Pycnocline: Laboratory Experiments  

Science Conference Proceedings (OSTI)

The convective building of a pycnocline is examined using a laboratory model forced by surface fluxes of saline water at one end and fresh water at the other. A deep recirculation evolves in the tank, which homogenizes the interior fluid by ...

David W. Pierce; Peter B. Rhines

1996-02-01T23:59:59.000Z

244

Transport Asymmetry in Skewed Convective Circulations  

Science Conference Proceedings (OSTI)

Two simple kinematical models are used to describe the asymmetry in bottom-up and top-down diffusion in the convective boundary layer. Both models resolve the mean circulation with narrow updrafts and wider downdrafts but differ in the treatment ...

Ulrich Schumann

1993-01-01T23:59:59.000Z

245

`Convective` flat plate collectors and their applications  

SciTech Connect

The `convective` flat plate collector is a particular two-way collector system with air in gravity flow as primary working fluid. Its thermal characteristics are described. Results of outdoor tests and thermal simulations are shown. Different applications of the system are presented: water heating, steam generation for medical sterilization, solar cooking and space heating. 10 refs., 16 figs., 6 tabs.

Grupp, M.; Bergler, H.; Bertrand, J.P. [Synopsis, Lodeve (France); Kromer, B. [Institut fuer Umweltphysik der Universtaet, Heidelberg (Germany); Cieslok, J. [INCO, Aachen (Germany)

1995-12-31T23:59:59.000Z

246

A Simple Method for Measuring Deep Convection  

Science Conference Proceedings (OSTI)

The glass-pipe technology used for RAFOS floats is applied to the monitoring of convection in deep mixed layers. The velocity of a vertical current is estimated from the relationship between the drag force exerted on a float by the vertical ...

Edward J. Kearns; H. Thomas Rossby

1993-08-01T23:59:59.000Z

247

Urinary 1-hydroxypyrene concentrations in Chinese coke oven workers relative to job category, respirator usage, and cigarette smoking  

SciTech Connect

1-Hydroxypyrene (1-OHP) is a biomarker of recent exposure to polycyclic aromatic hydrocarbons (PAHs). We investigated whether urinary 1-OHP concentrations in Chinese coke oven workers (COWs) are modulated by job category, respirator usage, and cigarette smoking. The present cross-sectional study measured urinary 1-OHP concentrations in 197 COWs from Coking plant I and 250 COWs from Coking plant II, as well as 220 unexposed referents from Control plant I and 56 referents from Control plant II. Urinary 1-OHP concentrations (geometric mean, {mu}mol/mol creatinine) were 5.18 and 4.21 in workers from Coking plants I and II, respectively. The highest 1-OHP levels in urine were found among topside workers including lidmen, tar chasers, and whistlers. Benchmen had higher 1-OHP levels than other workers at the sideoven. Above 75% of the COWs exceeded the recommended occupational exposure limit of 2.3 {mu}mol/mol creatinine. Respirator usage and increased body mass index (BMI) slightly reduced 1-OHP levels in COWs. Cigarette smoking significantly increased urinary 1-OHP levels in unexposed referents but had no effect in COWs. Chinese COWs, especially topside workers and benchmen, are exposed to high levels of PAHs. Urinary 1-OHP concentrations appear to be modulated by respirator usage and BMI in COWs, as well as by smoking in unexposed referents.

Bo Chen; Yunping Hu; Lixing Zheng; Qiangyi Wang; Yuanfen Zhou; Taiyi Jin [Fudan University, Shanghai (China). School of Public Health

2007-09-15T23:59:59.000Z

248

Technical support document: Energy efficiency standards for consumer products: Room air conditioners, water heaters, direct heating equipment, mobile home furnaces, kitchen ranges and ovens, pool heaters, fluorescent lamp ballasts and television sets. Volume 2, Fluorescent lamp ballasts, television sets, room air conditioners, and kitchen ranges and ovens  

SciTech Connect

This document is divided into ``volumes`` B through E, dealing with individual classes of consumer products. Chapters in each present engineering analysis, base case forecasts, projected national impacts of standards, life-cycle costs and payback periods, impacts on manufacturers, impacts of standards on electric utilities, and environmental effects. Supporting appendices are included.

Not Available

1993-11-01T23:59:59.000Z

249

Wind reversals in turbulent Rayleigh-Benard convection  

E-Print Network (OSTI)

The phenomenon of irregular cessation and subsequent reversal of the large-scale circulation in turbulent Rayleigh-B\\'enard convection is theoretically analysed. The force and thermal balance on a single plume detached from the thermal boundary layer yields a set of coupled nonlinear equations, whose dynamics is related to the Lorenz equations. For Prandtl and Rayleigh numbers in the range $10^{-2} \\leq \\Pr \\leq 10^{3}$ and $10^{7} \\leq \\Ra \\leq 10^{12}$, the model has the following features: (i) chaotic reversals may be exhibited at Ra $\\geq 10^{7}$; (ii) the Reynolds number based on the root mean square velocity scales as $\\Re_{rms} \\sim \\Ra^{[0.41 ... 0.47]}$ (depending on Pr), and as $\\Re_{rms} \\sim \\Pr^{-[0.66 ... 0.76]}$ (depending on Ra); and (iii) the mean reversal frequency follows an effective scaling law $\\omega / (\

Francisco Fontenele Araujo; S. Grossmann; D. Lohse

2004-07-13T23:59:59.000Z

250

Building and Fire Publications  

Science Conference Proceedings (OSTI)

... kitchens; cooking appliances; cooking tops; energy consumption; energy efficiency; kitchen appliances; microwave ovens; ovens; ranges; test ...

251

Convective transport in laser target plasmas  

SciTech Connect

The role of guiding-center corrections in convective transport of electron energy is examined with a simple numerical model. At 10/sup 16/W cm/sup -2/ with a 60-..mu..m spot and a 10.6-..mu..m wavelength laser, the Righi-Leduc term is observed to have little effect on transport in a calculation with the thermal flux limited to the free-streaming value.

Brackbill, J.U.; Colombant, D.; Grandjouan, N.

1982-01-01T23:59:59.000Z

252

HIGH-RESOLUTION SIMULATIONS OF CONVECTION PRECEDING IGNITION IN TYPE Ia SUPERNOVAE USING ADAPTIVE MESH REFINEMENT  

E-Print Network (OSTI)

We extend our previous three-dimensional, full-star simulations of the final hours of convection preceding ignition in Type Ia supernovae to higher resolution using the adaptive mesh refinement capability of our low Mach number code, MAESTRO. We report the statistics of the ignition of the first flame at an effective 4.34 km resolution and general flow field properties at an effective 2.17 km resolution. We find that off-center ignition is likely, with radius of 50 km most favored and a likely range of 40–75 km. This is consistent with our previous coarser (8.68 km resolution) simulations, implying that we have achieved sufficient resolution in our determination of likely ignition radii. The dynamics of the last few hot spots preceding ignition suggest that a multiple ignition scenario is not likely. With improved resolution, we can more clearly see the general flow pattern in the convective region, characterized by a strong outward plume with a lower speed recirculation. We show that the convective core is turbulent with a Kolmogorov spectrum and has a lower turbulent intensity and larger integral length scale than previously thought (on the order of 16 km s?1 and 200 km, respectively), and we discuss the potential consequences for the first flames. Key words: convection – hydrodynamics – methods: numerical – nuclear reactions, nucleosynthesis, abundances – supernovae: general – white dwarfs Online-only material: color figures 1.

A. Nonaka; A. J. Aspden; M. Zingale; A. S. Almgren; J. B. Bell; S. E. Woosley

2012-01-01T23:59:59.000Z

253

Convective heat transport in geothermal systems  

DOE Green Energy (OSTI)

Most geothermal systems under exploitation for direct use or electrical power production are of the hydrothermal type, where heat is transferred essentially by convection in the reservoir, conduction being secondary. In geothermal systems, buoyancy effects are generally important, but often the fluid and heat flow patterns are largely controlled by geologic features (e.g., faults, fractures, continuity of layers) and location of recharge and discharge zones. During exploitation, these flow patterns can drastically change in response to pressure and temperature declines, and changes in recharge/discharge patterns. Convective circulation models of several geothermal systems, before and after start of fluid production, are described, with emphasis on different characteristics of the systems and the effects of exploitation on their evolution. Convective heat transport in geothermal fields is discussed, taking into consideration (1) major geologic features; (2) temperature-dependent rock and fluid properties; (3) fracture- versus porous-medium characteristics; (4) single- versus two-phase reservoir systems; and (5) the presence of noncondensible gases.

Lippmann, M.J.; Bodvarsson, G.S.

1986-08-01T23:59:59.000Z

254

RADIO RANGING DEVICE  

DOE Patents (OSTI)

A radio ranging device is described. It utilizes a super regenerative detector-oscillator in which echoes of transmitted pulses are received in proper phase to reduce noise energy at a selected range and also at multiples of the selected range.

Nieset, R.T.

1961-05-16T23:59:59.000Z

255

Impacts of Initial Estimate and Observation Availability on Convective-Scale Data Assimilation with an Ensemble Kalman Filter  

Science Conference Proceedings (OSTI)

The ensemble Kalman filter (EnKF) uses an ensemble of short-range forecasts to estimate the flow-dependent background error covariances required in data assimilation. The feasibility of the EnKF for convective-scale data assimilation has been ...

F. Zhang; Chris Snyder; Juanzhen Sun

2004-05-01T23:59:59.000Z

256

The convective structures associated with cloud-to-ground lightning in TOGA COARE Mesoscale Convective Systems  

E-Print Network (OSTI)

The TOGA COARE experiment was carried out in the western Pacific warm pool region from November 1992 through February 1993. Data from TOGA COARE provide the opportunity for comprehensive studies of tropical oceanic convection. This study seeks to understand more about the structures of tropical mesoscale convective systems in relation to their lightning activity and cold cloud area. The properties of convective cores within the MCSs, as well as their infrared (IR) cloud top temperatures are related to cloud-to-ground lightning. IR and lightning time histories for each case are compared, and the cases ranked by mean flashes per 10000 km2. For selected cases, radar/lightning overlays and vertical profiles of maximum radar reflectivities (VPRRs) are shown in order to describe the convective structures of cells that produced lightning, and also cells that did not produce lightning. IR cloud-top temperature and lightning histories indicate the highly variable nature of the TOGA COARE MCSs. Some MCSs which have very cold cloud-top temperatures have little or no lightning. When a system did produce lightning, more flashes generally occurred during its growth phase. Overall, IR measurements seem to be a poor indicator of lightning due to the lack of a clear relationship between the size of cold cloud-top area and cloud-to-ground flashes. The overall flash rates of the TOGA COARE MCSs support previous work which showed that tropical oceanic convection has an order of magnitude less cloud-to-ground lightning than continental convection. In fact, the highest flash rate for the 13 cases was less than the weakest continental case in a Texas MCS study (Toracinta et al. 1995). Examination of individual VPRR and of all convective VPRR from the 13 cases indicate a pronounced difference between lightning producing and non-lightning producing cells. Lightning producing convective cells have higher radar reflectivity in the 5.0- 8.0 km layer, and a slower decrease with height, both observations indicating larger ice particles in the mixed phase region between 00 C and-200 C.

Restivo, Michael Edward

1995-01-01T23:59:59.000Z

257

ARM - Field Campaign - Midlatitude Continental Convective Clouds Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

Experiment (MC3E) Experiment (MC3E) Campaign Links Science Plan MC3E Website Related Campaigns Midlatitude Continental Convective Clouds Experiment: 2DVD Support 2011.04.22, Schwaller, SGP Midlatitude Continental Convective Clouds Experiment (MC3E): Airborne Instruments 2011.04.22, Poellot, AAF Midlatitude Continental Convective Clouds Experiment (MC3E): Multi-Frequency Profilers 2011.04.22, Williams, SGP Midlatitude Continental Convective Clouds Experiment: Parsivel Disdrometer Support 2011.04.22, Schwaller, SGP Midlatitude Continental Convective Clouds Experiment (MC3E): Inner Domain Thermodynamic Profiling during MC3E 2011.04.22, Turner, SGP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Midlatitude Continental Convective Clouds Experiment (MC3E)

258

PROPAGATION OF GRAVITY WAVES IN A CONVECTIVE LAYER  

SciTech Connect

We perform numerical simulations of gravity mode propagation in a convective layer to investigate the observed association between small spatial scales and low frequencies in the photospheric velocity fields. According to the linear theory, when the fluid layer is convectively unstable, gravity modes are evanescent waves. However, in simple two-dimensional numerical settings, we find that when the equilibrium structure is modified by coherent large-scale convective motions, the waves injected at the bottom of the layer are no longer evanescent. In this situation, gravity waves can be detected at the surface of the layer. In our simplified model the injected wave's frequency remains unchanged, but its amplitude has a spatial modulation determined by the convective structure. This result may explain some analyses done with the proper orthogonal decomposition method of the solar surface velocity field even though solar convection is far more complex than the convection model considered here.

Onofri, M.; Vecchio, A.; Veltri, P. [Dipartimento di Fisica, Universita della Calabria, via P. Bucci, 87036 Rende (Italy); De Masi, G., E-mail: onofri@fis.unical.it [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, 35127 Padova (Italy)

2012-02-10T23:59:59.000Z

259

Tracer Gas Transport under Mixed Convection Conditions in an Experimental  

NLE Websites -- All DOE Office Websites (Extended Search)

Tracer Gas Transport under Mixed Convection Conditions in an Experimental Tracer Gas Transport under Mixed Convection Conditions in an Experimental Atrium: Comparison Between Experiments and CFD Predictions Title Tracer Gas Transport under Mixed Convection Conditions in an Experimental Atrium: Comparison Between Experiments and CFD Predictions Publication Type Journal Article Year of Publication 2006 Authors Jayaraman, Buvaneswari, Elizabeth U. Finlayson, Michael D. Sohn, Tracy L. Thatcher, Phillip N. Price, Emily E. Wood, Richard G. Sextro, and Ashok J. Gadgil Journal Atmospheric Environment Volume 40 Start Page Chapter Pagination 5236-5250 Keywords airflow and pollutant transport group, atria, indoor airflow and pollutant transport, indoor environment department, indoor pollutant dispersion, mixed convection, turbulence model

260

Thermal Convection: Patterns, Evolution and Stability by M. Lappa  

E-Print Network (OSTI)

Review of the book "Thermal Convection: Patterns, Evolution and Stability" by M. Lappa. Invited by the journal Geophysical and Astrophysical Fluid Dynamics.

Simitev, R D

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

New Insights Into Deep Convective Core Vertical Velocities Using...  

NLE Websites -- All DOE Office Websites (Extended Search)

Insights Into Deep Convective Core Vertical Velocities Using ARM UHF Wind Profilers For original submission and image(s), see ARM Research Highlights http:www.arm.govscience...

262

Comparison between experiments and CFD predictions of mixed convection...  

NLE Websites -- All DOE Office Websites (Extended Search)

results from a computational fluid dynamics (CFD) simulation of airflow and pollutant dispersion under mixed-convection conditions with experimental data obtained in our 7m x...

263

Drift Natural Convection and Seepage at the Yucca Mountain Repository  

E-Print Network (OSTI)

multiphase mass and heat transfer processes[26, 33], in bothdrift environment heat transfer processes are a multifacetedof convective heat transfer processes, but how is it that we

Halecky, Nicholaus Eugene

2010-01-01T23:59:59.000Z

264

A Review of Convection Initiation and Motivation for IHOP_2002  

Science Conference Proceedings (OSTI)

The International H2O Project (IHOP_2002) included four complementary research components: quantitative precipitation forecasting, convection initiation, atmospheric boundary layer processes, and instrumentation. This special issue introductory ...

Tammy M. Weckwerth; David B. Parsons

2006-01-01T23:59:59.000Z

265

Diurnal Cycle of Convection at the ARM SGP Site: Role of Large-Scale Forcing, Surface Fluxes, and Convective Inhibition  

NLE Websites -- All DOE Office Websites (Extended Search)

Diurnal Cycle of Convection at the ARM SGP Site: Diurnal Cycle of Convection at the ARM SGP Site: Role of Large-Scale Forcing, Surface Fluxes, and Convective Inhibition G. J. Zhang Center for Atmospheric Sciences Scripps Institution of Oceanography La Jolla, California Introduction Atmospheric convection undergoes strong diurnal variation over both land and oceans (Gray and Jacobson 1977; Dai 2001; Nesbitt and Zipser 2003). Because of the nature of the diurnal variation of solar radiation, the phasing of convection with solar radiation has a significant impact on the atmospheric radiation budget and cloud radiative forcing. A number of studies have investigated the possible mechanisms of the diurnal variation of convection (Gray and Jacobson 1977; Randall et al. 1991; Dai et al. 1999; Dai 2001). Yet, in regional and global climate models, the diurnal variation of

266

Oven | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Energy 101: Solar PV Sec. Chu Online Town Hall Energy 101: Cool Roofs Energy 101: Geothermal Heat Pumps Why Cool Roofs? Chu at COP-16: Building a Sustainable Energy Future...

267

Oven | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Kill-a-Watt Competition at University of Central Florida Faces of the Recovery Act: Sun Catalytix Investing in Clean, Safe Nuclear Energy Secretary Chu Speaks at the 2010...

268

Oven | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Recovery Act Transforming the American Economy Through Innovation Linac Coherent Light Source Overview Matt Rogers on AES Energy Storage Energy 101: Concentrating Solar Power...

269

Oven | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Pledge? Conversation on the Future of the Wind Industry Science Lecture: Talking the Higgs Boson with Dr. Joseph Incandela Bill Gates and Deputy Secretary Poneman Discuss the...

270

Oven | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

The Future of Biofuels The Climate Challenge... and What's at Stake Sec. Chu Announces the First Auto Loans for Advanced Technologies...

271

Oven | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Security & Safety -Emergency Response & Procedures or Search Energy.gov Search Clear Filters All Videos ARPA-E 2011 Keynote: Ray Mabus, Secretary of the Navy Electrofuels:...

272

Long range dependence  

Science Conference Proceedings (OSTI)

The notion of long range dependence is discussed from a variety of points of view, and a new approach is suggested. A number of related topics is also discussed, including connections with non-stationary processes, with ergodic theory, self-similar processes ... Keywords: large deviations, long range dependence, rare events

Gennady Samorodnitsky

2007-01-01T23:59:59.000Z

273

Convection with Rotation in a Neutral Ocean: A Study of Open-Ocean Deep Convection  

Science Conference Proceedings (OSTI)

The intensity and scale of the geostrophically adjusted end state of the convective overturning of a homogeneous rotating ocean of depth H at a latitude where the Coriolis parameter is f, induced by surface buoyancy loss of magnitude B0, are ...

Helen Jones; John Marshall

1993-06-01T23:59:59.000Z

274

The Wake Uw in a Midlatitude Mesoseale Convective System Having Complex Convective Organintion  

Science Conference Proceedings (OSTI)

An analysis has been carried out of the surface pressure field in a highly complex mesoscale convective system that occurred on 3-4 June 1985 during the Oklahoma-Kansas Preliminary Regional Expeximent for STORM-Central (OK PRE-STORM). During its ...

Gregory J. Stumpf; Richard H. Johnson; Bradley F. Smull

1991-01-01T23:59:59.000Z

275

Tropical Wave Instabilities: Convective Interaction with Dynamics Using the Emanuel Convective Parameterization  

Science Conference Proceedings (OSTI)

Wave-CISK and evaporation-wind feedback modes, also known as WISHE (wind-induced surface heat exchange) modes, are investigated using a two-dimensional (x?p), hydrostatic, nonrotational model linearized about a basic state in radiative-convective ...

Randy G. Brown; Christopher S. Bretherton

1995-01-01T23:59:59.000Z

276

Radiative-Convective Equilibrium with Explicit Two-Dimensional Moist Convection  

Science Conference Proceedings (OSTI)

Radiative-convective statistical equilibria are obtained using a two-dimensional model in which radiative transfer is interactive with the predicted moisture and cloud fields. The domain is periodic in x, with a width of 640 km, and extends from ...

Isaac M. Held; Richard S. Hemler; V. Ramaswamy

1993-12-01T23:59:59.000Z

277

Natural convection airflow measurement and theory  

DOE Green Energy (OSTI)

Natural convection is a major mechanism for heat distribution in many passive solar buildings, especially those with sunspaces. To better understand this mechanism, observations of air velocities and temperatures have been made in 13 different houses that encompass a wide variety of one- and two-story geometries. This paper extends previous reports. Results from one house are described in detail, and some generalizations are drawn from the large additional mass of data taken. A simple mathematical model is presented that describes the general nature of airflow and energy flow through an aperture.

Balcomb, J.D.; Jones, G.F.; Yamaguchi, Kenjiro

1984-01-01T23:59:59.000Z

278

The Relation between Moist Convective Adjustment Schemes and the Mass-Flux Concept for Cumulus Parameterization  

Science Conference Proceedings (OSTI)

The problem of finding convective mass fluxes and convective condensation rates in moist convective adjustment schemes for cumulus parameterization in numerical weather prediction is addressed. Formal considerations reveal that, in general, it is ...

Peter Binder

1993-12-01T23:59:59.000Z

279

The Kinematics of a Midlatitude, Continental Mesoscale Convective System and Its Mesoscale Vortex  

Science Conference Proceedings (OSTI)

The authors present a unique, scale-discriminating study of the environment-relative circulations within a mesoscale convective system (MCS) and mesoscale convective vortex (MCV). The MCS, a leading convective line and trailing stratiform region ...

Jason C. Knievel; Richard H. Johnson

2002-07-01T23:59:59.000Z

280

Structure of a Midtropospheric Vortex Induced by a Mesoscale Convective System  

Science Conference Proceedings (OSTI)

On 9 June 1988 a mesoscale (200-km diameter) convectively generated vortex (MCV) passed through the Colorado wind-profiling network. The generating convective system, which was too small to meet Maddox’s mesoscale convective complex criteria, ...

Diana L. Bartels; John M. Brown; Edward I. Tollerud

1997-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Analysis of Convectively Coupled Kelvin Waves in the Indian Ocean MJO  

Science Conference Proceedings (OSTI)

The active convective phase of the Madden–Julian oscillation (hereafter active MJO) comprises enhanced moist deep convection on its own temporal and spatial scales as well as increased variance in convection associated with higher-frequency ...

Paul E. Roundy

2008-04-01T23:59:59.000Z

282

Prediction of convective morphology in near-cloud permitting WRF model simulations  

Science Conference Proceedings (OSTI)

The Weather Research and Forecasting (WRF) model’s ability to forecast convective morphological evolution is examined for 37 convective systems. The simulations used Thompson microphysics with 3-km horizontal grid spacing. Ten convective mode ...

Darren V. Snively; William A. Gallus; Jr.

283

The Initiation and Evolution of Multiple Modes of Convection within a Meso-Alpha-Scale Region  

Science Conference Proceedings (OSTI)

On 30 March 2006, a convective episode occurred featuring isolated supercells, a mesoscale convective system (MCS) with parallel stratiform (PS) precipitation, and an MCS with leading stratiform (LS) precipitation. These three distinct convective ...

Adam J. French; Matthew D. Parker

2008-12-01T23:59:59.000Z

284

Sensitivities of a Squall Line over Central Europe in a Convective-Scale Ensemble  

Science Conference Proceedings (OSTI)

Convective-scale ensemble simulations with perturbed initial and lateral boundary conditions are performed to investigate the mechanisms and sensitivities of a central European convection event from the Convective and Orographically Induced ...

K. E. Hanley; D. J. Kirshbaum; N. M. Roberts; G. Leoncini

2013-01-01T23:59:59.000Z

285

Practical and Intrinsic Predictability of Severe and Convective Weather at the Mesoscales  

Science Conference Proceedings (OSTI)

This study explores both the practical and intrinsic predictability of severe convective weather at the mesoscales using convection-permitting ensemble simulations of a squall line and bow echo event during the Bow Echo and Mesoscale Convective ...

Christopher Melhauser; Fuqing Zhang

2012-11-01T23:59:59.000Z

286

Dynamics of Orographically Triggered Banded Convection in Sheared Moist Orographic Flows  

Science Conference Proceedings (OSTI)

Shallow orographic convection embedded in an unstable cap cloud can organize into convective bands. Previous research has highlighted the important role of small-amplitude topographic variations in triggering and organizing banded convection. ...

Oliver Fuhrer; Christoph Schär

2007-10-01T23:59:59.000Z

287

Orogenic Convection in Subtropical South America as Seen by the TRMM Satellite  

Science Conference Proceedings (OSTI)

Extreme orogenic convective storms in southeastern South America are divided into three categories: storms with deep convective cores, storms with wide convective cores, and storms containing broad stratiform regions. Data from the Tropical ...

Kristen L. Rasmussen; Robert A. Houze Jr.

2011-08-01T23:59:59.000Z

288

Convection in a porous medium and mimetic scheme in polar coordinates  

Science Conference Proceedings (OSTI)

Analytical investigation of natural convection of the incompressible fluid in the porous media based on the Darcy hypothesis (Lapwood convection) gives intriguing branching off of one-parameter family of convective patterns. This scenario may be suppressed ...

Bülent Karasözen; Anastasia Trofimova; Vyacheslav Tsybulin

2011-09-01T23:59:59.000Z

289

Climatic regimes of tropical convection and rainfall  

SciTech Connect

Annual distribution and phase propagation of tropical convection are delineated using harmonic and amplitude-phase characteristics analysis of climatological pentad mean outgoing longwave radiation and monthly frequencies of highly reflective cloud. An annual eastward propagation of peak rainy season along the equator from the central Indian Ocean (60[degrees]E) to Arafura Sea (130[degrees]E) is revealed. This indicates a transition from the withdrawal of the Indian summer monsoon to the onset of the Australian summer monsoon. Significant bimodal variations are found around major summer monsoon regions. These variations originate from the interference of two adjacent regimes. The convergence zones over the eastern North Pacific, the South Pacific, and the southwest Indian Ocean are identified as a marine monsoon regime that is characterized by a unimodal variation with a concentrated summer rainfall associated with the development of surface westerlies equatorward of a monsoon trough. Conversely, the central North Pacific and North Atlantic convergence zones between persistent northeast and southeast trades are classified as trade-wind convergence zones; which differ from the marine monsoon regime by their persistent rainy season and characteristic bimodal variation with peak rainy seasons occurring in late spring and fall. The roles of the annual march of sea surface temperature in the phase propagation and formation of various climatic regimes of tropical convection are also discussed. 34 refs., 8 figs., 1 tab.

Wang, Bin (Univ. of Hawaii, Honolulu, HI (United States))

1994-07-01T23:59:59.000Z

290

Cloud-Resolving Simulations of Mesoscale Vortex Intensification and Its Effect on a Serial Mesoscale Convective System  

Science Conference Proceedings (OSTI)

The authors performed numerical simulations of the 27–28 May 1998 mesoscale convective vortex (MCV) and mesoscale convective system (MCS) to understand how the MCV modulated the convection, and how the convection intensified the vortex. The fifth-...

Christopher A. Davis; Stanley B. Trier

2002-12-01T23:59:59.000Z

291

Realized and projected impacts of U.S. federal efficiency standards for residential appliances  

E-Print Network (OSTI)

kitchen ranges and ovens, direct heating equipment (wall,Ranges and Ovens Pool Heaters Direct Heating Equipment X =Heating Equipment, Mobile Home Furnaces, Kitchen Ranges and Ovens,

Meyers, Stephen; McMahon, James; McNeil, Michael; Liu, Xiaomin

2002-01-01T23:59:59.000Z

292

Realized and prospective impacts of U.S. energy efficiency standards for residential appliances: 2004 update  

E-Print Network (OSTI)

kitchen ranges and ovens, direct heating equipment (wall,Ranges and Ovens Pool Heaters Direct Heating Equipment X =Heating Equipment, Mobile Home Furnaces, Kitchen Ranges and Ovens,

Meyers, Stephen; McMahon, James; McNeil, Michael

2005-01-01T23:59:59.000Z

293

Structure and evolution of a convective band MCS  

E-Print Network (OSTI)

The structure and evolution of the synoptic, mesoscale, and lightning characteristics of the 5 May 1993 non-squall line Mesoscale Convective System has been described. This storm was a long-lived Mesoscale Convective Complex. Its formation was influenced by strong low-level warm advection, weak vorticity advection, and weak vertical. wind shear. Its dissipation occurred as the storm encountered a more stable air mass which may have been influenced by storm induced subsidence. The cyclonic mesoscale circulation of the Mesoscale Convective Complex apparently aided in the formation of new lines of convection behind the primary convective line of the system. This process was repeated twice in the storm life cycle and led to multiple bands of convection. Indeed, this storm had three main lines: the leading line, the trailing one, and the small line near the center of the vortex. As the new lines formed, the vertical transport of momentum disrupted the symmetry of the mesovortex. However, as the line propagated eastward away from the vortex, the symmetric cyclonic circulation re-established itself. This Mesoscale Convective Complex produced flash rates in excess of 1000 h-I for twenty-four consecutive hours. The percentage of positive polarity flashes was higher during the formative and dissipating stages of the storm system. Positive flashes were also enhanced during mergers between convective bands. The flash locations during the mature stage of this storm suggest a bipolar pattern.

Valdes-Manzanilla, Arturo

1995-01-01T23:59:59.000Z

294

Gravity Waves in Shear and Implications for Organized Convection  

Science Conference Proceedings (OSTI)

It is known that gravity waves in the troposphere, which are often excited by preexisting convection, can favor or suppress the formation of new convection. Here it is shown that in the presence of wind shear or barotropic wind, the gravity waves ...

Samuel N. Stechmann; Andrew J. Majda

2009-09-01T23:59:59.000Z

295

Gravity Waves in Shear and Implications for Organized Convection  

E-Print Network (OSTI)

Gravity Waves in Shear and Implications for Organized Convection Samuel N. Stechmann Department, Los Angeles, CA 90095­1555. E-mail: stechmann@math.ucla.edu #12;ABSTRACT It is known that gravity, the gravity waves can create a more favorable environment on one side of preexisting convection than the other

Stechmann, Samuel N.

296

Rapidly Rotating Suns and Active Nests of Convection  

E-Print Network (OSTI)

In the solar convection zone, rotation couples with intensely turbulent convection to drive a strong differential rotation and achieve complex magnetic dynamo action. Our sun must have rotated more rapidly in its past, as is suggested by observations of many rapidly rotating young solar-type stars. Here we explore the effects of more rapid rotation on the global-scale patterns of convection in such stars and the flows of differential rotation and meridional circulation which are self-consistently established. The convection in these systems is richly time dependent and in our most rapidly rotating suns a striking pattern of localized convection emerges. Convection near the equator in these systems is dominated by one or two nests in longitude of locally enhanced convection, with quiescent streaming flow in between at the highest rotation rates. These active nests of convection maintain a strong differential rotation despite their small size. The structure of differential rotation is similar in all of our more rapidly rotating suns, with fast equators and slower poles. We find that the total shear in differential rotation Delta Omega grows with more rapid rotation while the relative shear Delta Omega/Omega_0 decreases. In contrast, at more rapid rotation the meridional circulations decrease in energy and peak velocities and break into multiple cells of circulation in both radius and latitude.

Benjamin P. Brown; Matthew K. Browning; Allan Sacha Brun; Mark S. Miesch; Juri Toomre

2008-08-12T23:59:59.000Z

297

Solar Convection Simulations using a B-spline method  

E-Print Network (OSTI)

This report outlines the development of a B-spline--spectral numerical code for the simulation of convection flows. It allows changing the spatial resolution in all three coordinates as a function of depth, which is especially advantageous for simulations of solar convection.

Hartlep, Thomas

2008-01-01T23:59:59.000Z

298

Solar Convection Simulations using a B-spline method  

E-Print Network (OSTI)

This report outlines the development of a B-spline--spectral numerical code for the simulation of convection flows. It allows changing the spatial resolution in all three coordinates as a function of depth, which is especially advantageous for simulations of solar convection.

Thomas Hartlep; Nagi N. Mansour

2008-05-05T23:59:59.000Z

299

Sensitivity of Tropical Convection to Land Surface Processes  

Science Conference Proceedings (OSTI)

This paper studies the sensitivity of large-scale tropical convection to land surface changes in the general circulation model of the LMD. Ale method of analysis is based on a conceptual model of the energetics of convection applied every day of ...

J. Polcher

1995-09-01T23:59:59.000Z

300

Environmental Distinctions between Cellular and Slabular Convective Lines  

Science Conference Proceedings (OSTI)

The organizational mode of quasi-linear convective systems often falls within a spectrum of modes described by a line of discrete cells on one end (“cellular”) and an unbroken two-dimensional swath of ascent on the other (“slabular”). Convective ...

Richard P. James; J. Michael Fritsch; Paul M. Markowski

2005-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Measurement of Simulated Convective Temperature Distribution Near Ancient Wall Paintings  

Science Conference Proceedings (OSTI)

This study presents a method for measuring the temperature distribution in a confined volume of water used to simulate heat convection in the air. The water was seeded with thermo sensitive crystals as an indicator for the temperature. A 1:10 scale model ... Keywords: air modeling in water, natural convection, thermo-sensitive liquid crystals

V. S. Fonov; C. F. Joeckel; I. Grant

2001-04-01T23:59:59.000Z

302

Boundary layer solutions for natural convection in porous media  

DOE Green Energy (OSTI)

An approximate solution is developed for natural convection in porous media resulting from localized heat sources. The method is applicable for moderate levels of convection. Results of the method compare well with those of other calculational methods and with experimental data. The solution for a spherical source can be used as an indirect method for the determination of permeability in some cases.

Hardee, H.C.

1976-05-01T23:59:59.000Z

303

East Asian Summer monsoon precipitation systems: rainfall characteristics, storm morphologies and convective properties.  

E-Print Network (OSTI)

??This study attempts to characterize the particular convection type, namely storm morphologies, convective properties, and microphysics, of different weather regimes within the East Asian Summer… (more)

Xu, Weixin

2011-01-01T23:59:59.000Z

304

Parameterization of Convective Precipitation in Mesoscale Numerical Models: A Critical Review  

Science Conference Proceedings (OSTI)

Current approaches for incorporating cumulus convection into mesoscale numerical models are divided into three groups. The traditional approach utilizes cumulus parameterization at convectively unstable points and explicit (nonparameterized) ...

John Molinari; Michael Dudek

1992-02-01T23:59:59.000Z

305

Patterns of Convection in the Tropical Western Pacific  

NLE Websites -- All DOE Office Websites (Extended Search)

Patterns of Convection in the Tropical Western Pacific Patterns of Convection in the Tropical Western Pacific J. H. Mather Pacific Northwest National Laboratory Richland, Washington Introduction Convection is ubiquitous throughout the maritime continent region. However, the frequency of convec- tion is not uniform. While much of this region does not experience seasons to the same degree as one finds in mid-latitudes, the annual cycle of the sun's passage does have a large impact on convection throughout the maritime continent and the tropical western Pacific. The distribution of islands also affects convection in a variety of ways. Atmospheric Radiation Measurement (ARM) Program has three sites in the Tropical Western Pacific (TWP) region, illustrated in Figure 1. The sites are located on Manus, Nauru, and at Darwin, Australia.

306

ARM - Field Campaign - Year of Tropical Convection (YOTC)  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsYear of Tropical Convection (YOTC) govCampaignsYear of Tropical Convection (YOTC) Campaign Links Year of Tropical Convection Website Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Year of Tropical Convection (YOTC) 2008.05.01 - 2010.04.30 Lead Scientist : Sally McFarlane Description Example of a sonde profile available from the ARM Archive The realistic representation of tropical convection in global atmospheric models is a long-standing challenge for weather and global climate models. The lack of fundamental knowledge in this area causes difficulties in modeling and predicting prominent phenomena of the tropical atmosphere such as the inter-tropical convergence zone (ITCZ), El-Nino/Southern Oscillation (ENSO), monsoons, the Madden-Julian Oscillation (MJO), tropical cyclones,

307

BNL | Midlatitude Continental Convective Clouds Experiment (MC3E)  

NLE Websites -- All DOE Office Websites (Extended Search)

Midlatitude Continental Convective Clouds Experiment Midlatitude Continental Convective Clouds Experiment Convective processes play a critical role in the Earth's energy balance through the redistribution of heat and moisture in the atmosphere and their link to the hydrological cycle. Accurate representation of convective processes in numerical models is vital towards improving current and future simulations of Earths climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales important to convective processes and therefore must turn to parameterization schemes to represent these processes. In turn, parameterization schemes in cloud-resolving models need to be evaluated for their generality and application to a

308

Limiting Factors for Convective Cloud Top Height in the Tropics  

NLE Websites -- All DOE Office Websites (Extended Search)

Limiting Factors for Convective Cloud Top Limiting Factors for Convective Cloud Top Height in the Tropics M. P. Jensen and A. D. Del Genio National Aeronautics and Space Administration Goddard Institute for Space Studies Columbia University New York, New York Introduction Populations of tropical convective clouds are mainly comprised of three types: shallow trade cumulus, mid-level cumulus congestus and deep convective clouds (Johnson et al. 1999). Each of these cloud types has different impacts on the local radiation and water budgets. For climate model applications it is therefore important to understand the factors which determine the type of convective cloud that will occur. In this study, we concentrate on describing the factors that limit the cloud-top heights of mid-

309

Effects of Varying the Shape of the Convective Heating Profile on Convectively Coupled Gravity Waves and Moisture Modes  

Science Conference Proceedings (OSTI)

The analytical model of convectively coupled gravity waves and moisture modes of Raymond and Fuchs is extended to the case of top-heavy and bottom-heavy convective heating profiles. Top-heavy heating profiles favor gravity waves, while bottom-...

Željka Fuchs; Saska Gjorgjievska; David J. Raymond

2012-08-01T23:59:59.000Z

310

Comparison of the Diurnal Precipitation Cycle in Convection-Resolving and Non-Convection-Resolving Mesoscale Models  

Science Conference Proceedings (OSTI)

The diurnal cycles of rainfall in 5-km grid-spacing convection-resolving and 22-km grid-spacing non-convection-resolving configurations of the Weather Research and Forecasting (WRF) model are compared to see if significant improvements can be ...

Adam J. Clark; William A. Gallus Jr.; Tsing-Chang Chen

2007-10-01T23:59:59.000Z

311

Long-Term Simulations of Thermally Driven Flows and Orographic Convection at Convection-Parameterizing and Cloud-Resolving Resolutions  

Science Conference Proceedings (OSTI)

The purpose of this paper is to validate the representation of topographic flows and moist convection over the European Alps in a convection-parameterizing simulation (CPM; ?x = 6.6 km) and two cloud-resolving simulations (CRM; ?x = 1.1 and 2.2 km)...

Wolfgang Langhans; Juerg Schmidli; Oliver Fuhrer; Susanne Bieri; Christoph Schär

2013-06-01T23:59:59.000Z

312

FLUX EMERGENCE IN A MAGNETIZED CONVECTION ZONE  

Science Conference Proceedings (OSTI)

We study the influence of a dynamo magnetic field on the buoyant rise and emergence of twisted magnetic flux ropes and their influence on the global external magnetic field. We ran three-dimensional MHD numerical simulations using the ASH code (anelastic spherical harmonics) and analyzed the dynamical evolution of such buoyant flux ropes from the bottom of the convection zone until the post-emergence phases. The global nature of this model can only very crudely and inaccurately represent the local dynamics of the buoyant rise of the implanted magnetic structure, but nonetheless allows us to study the influence of global effects, such as self-consistently generated differential rotation and meridional circulation, and of Coriolis forces. Although motivated by the solar context, this model cannot be thought of as a realistic model of the rise of magnetic structures and their emergence in the Sun, where the local dynamics are completely different. The properties of initial phases of the buoyant rise are determined essentially by the flux-rope's properties and the convective flows and consequently are in good agreement with previous studies. However, the effects of the interaction of the background dynamo field become increasingly strong as the flux ropes evolve. During the buoyant rise across the convection zone, the flux-rope's magnetic field strength scales as B{proportional_to}{rho}{sup {alpha}}, with {alpha} {approx}current density is observed to precede flux emergence at all longitudes. The geometry, latitude, and relative orientation of the flux ropes with respect to the background magnetic field influences the resulting rise speeds, zonal flow amplitudes (which develop within the flux ropes), and the corresponding surface signatures. This influences the morphology, duration and amplitude of the surface shearing, and the Poynting flux associated with magnetic flux-rope emergence. The emerged magnetic flux influences the system's global polarity, leading in some cases to a polarity reversal while inhibiting the background dynamo from doing so in others. The emerged magnetic flux is slowly advected poleward while being diffused and assimilated by the background dynamo field.

Pinto, R. F.; Brun, A. S., E-mail: rui.pinto@cea.fr [Laboratoire AIM Paris-Saclay, CEA/Irfu Universite Paris-Diderot CNRS/INSU, F-91191 Gif-sur-Yvette (France)

2013-07-20T23:59:59.000Z

313

Innovative coke oven gas cleaning system for retrofit applications. Quarterly environmental monitoring report No. 3, January 1, 1991--December 31, 1991  

Science Conference Proceedings (OSTI)

Bethlehem Steel Corporation (BSC), in conjunction with the Department of Energy (DOE) is conducting a Clean Coal Technology (CCT) project at its Sparrows Point, Maryland Coke Oven Plant. This project combines several existing technologies into an integrated system for removing impurities from Coke Oven Gas (COG) to make it an acceptable fuel. DOE is providing cost-sharing under a Cooperative Agreement with BSC. This Cooperative Agreement requires BSC to develop and conduct an Environmental Monitoring Plan (EMP) for the Clean Coal Technology project and to report the status of the EMP on a quarterly basis. This report is the third quarterly status report of the EMP. It covers the Environmental Monitoring Plan activities for the full year of 1991 from January 1, 1991 through December 31, 1991, including the forth quarter. See Sections 2, 3 and 4 for status reports of the Project Installation and Commissioning, the Environmental Monitoring activities and the Compliance Monitoring results for the period. Section 5 contains a list of Compliance Reports submitted to regulatory agencies during the period. The EMP describes in detail the environmental monitoring activities to be performed during the project execution. The purpose of the EMP is to: (1) document the extent of compliance of monitoring activities, i.e. those monitoring required to meet permit requirements, (2) confirm the specific impacts predicted in the National Environmental Policy Act documentation, and (3) establish an information base for the assessment of the environmental performance of the technology demonstrated by the project.

Not Available

1992-10-16T23:59:59.000Z

314

RADIO RANGING DEVICE  

DOE Patents (OSTI)

A description is given of a super-regenerative oscillator ranging device provided with radiating and receiving means and being capable of indicating the occurrence of that distance between itself and a reflecting object which so phases the received echo of energy of a preceding emitted oscillation that the intervals between oscillations become uniform.

Bogle, R.W.

1960-11-22T23:59:59.000Z

315

High dynamic range imaging  

Science Conference Proceedings (OSTI)

Current display devices can display only a limited range of contrast and colors, which is one of the main reasons that most image acquisition, processing, and display techniques use no more than eight bits per color channel. This course outlines recent ...

Paul Debevec; Erik Reinhard; Greg Ward; Sumanta Pattanaik

2004-08-01T23:59:59.000Z

316

Field data collection of miscellaneous electrical loads in Northern California: Initial results  

E-Print Network (OSTI)

and a convection oven that allows pre-heating like a typicalToaster ovens have fast warm-up infrared heating elements at

Greenblatt, Jeffery B.

2013-01-01T23:59:59.000Z

317

Reflections on dissipation associated with thermal convection  

E-Print Network (OSTI)

Buoyancy-driven convection is modelled using the Navier-Stokes and entropy equations. It is first shown that the coefficient of heat capacity at constant pressure, c_p, must in general depend explicitly on pressure (i.e. is not a function of temperature alone) in order to resolve a dissipation inconsistency. It is shown that energy dissipation in a statistically steady state is the time-averaged volume integral of - (D P)/(D t) and not that of - alpha T (D P)/(D t). Secondly, in the framework of the anelastic equations derived with respect to the adiabatic reference state, we obtain a condition when the anelastic liquid approximation can be made, gamma -1 << 1, independent of the dissipation number.

Thierry Alboussiere; Yanick Ricard

2012-10-19T23:59:59.000Z

318

Inside the supernova a powerful convective engine  

E-Print Network (OSTI)

We present an extensive study of the inception of supernova explosions by following the evolution of the cores of two massive stars (15 Msun and 25 Msun) in two dimensions. Our calculations begin at the onset of core collapse and stop several 100 ms after the bounce, at which time successful explosions of the appropriate magnitude have been obtained. (...) Guided by our numerical results, we have developed a paradigm for the supernova explosion mechanism. We view a supernova as an open cycle thermodynamic engine in which a reservoir of low-entropy matter (the envelope) is thermally coupled and physically connected to a hot bath (the protoneutron star) by a neutrino flux, and by hydrodynamic instabilities. (...) In essence, a Carnot cycle is established in which convection allows out-of-equilibrium heat transfer mediated by neutrinos to drive low entropy matter to higher entropy and therefore extracts mechanical energy from the heat generated by gravitational collapse. We argue that supernova explosions are ne...

Herant, M; Hix, W R; Fryer, C F; Colgate, S A; Marc Herant; Willy Benz; Chris F Fryer; Stirling Colgate

1994-01-01T23:59:59.000Z

319

MESA MODELS OF CLASSICAL NOVA OUTBURSTS: THE MULTICYCLE EVOLUTION AND EFFECTS OF CONVECTIVE BOUNDARY MIXING  

SciTech Connect

Novae are cataclysmic variables driven by accretion of H-rich material onto a white dwarf (WD) star from its low-mass main-sequence binary companion. New time-domain observational capabilities, such as the Palomar Transient Factory and Pan-STARRS, have revealed a diversity of their behavior that should be theoretically addressed. Nova outbursts depend sensitively on nuclear physics data, and more readily available nova simulations are needed in order to effectively prioritize experimental effort in nuclear astrophysics. In this paper, we use the MESA stellar evolution code to construct multicycle nova evolution sequences with CO WD cores. We explore a range of WD masses and accretion rates as well as the effect of different cooling times before the onset of accretion. In addition, we study the dependence on the elemental abundance distribution of accreted material and convective boundary mixing at the core-envelope interface. Models with such convective boundary mixing display an enrichment of the accreted envelope with C and O from the underlying WD that is commensurate with observations. We compare our results with the previous work and investigate a new scenario for novae with the {sup 3}He-triggered convection.

Denissenkov, Pavel A.; Herwig, Falk [Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Victoria, BC V8W 3P6 (Canada)] [Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Victoria, BC V8W 3P6 (Canada); Bildsten, Lars; Paxton, Bill, E-mail: pavelden@uvic.ca, E-mail: fherwig@uvic.ca, E-mail: bildsten@kitp.ucsb.edu, E-mail: paxton@kitp.ucsb.edu [Kavli Institute for Theoretical Physics and Department of Physics, Kohn Hall, University of California, Santa Barbara, CA 93106 (United States)] [Kavli Institute for Theoretical Physics and Department of Physics, Kohn Hall, University of California, Santa Barbara, CA 93106 (United States)

2013-01-01T23:59:59.000Z

320

RANGE DESIGN CRITERIA  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

RANGE DESIGN CRITERIA RANGE DESIGN CRITERIA U.S. DEPARTMENT OF ENERGY Office of Health, Safety and Security AVAILABLE ONLINE AT: INITIATED BY: http://www.hss.energy.gov Office of Health, Safety and Security Notices This document is intended for the exclusive use of elements of the Department of Energy (DOE), to include the National Nuclear Security Administration, their contractors, and other government agencies/individuals authorized to use DOE facilities. DOE disclaims any and all liability for personal injury or property damage due to use of this document in any context by any organization, group, or individual, other than during official government activities. Local DOE management is responsible for the proper execution of firearms-related programs for

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Evaporation of Picolitre Droplets on Surfaces with a Range of Wettabilities and Thermal Conductivities  

E-Print Network (OSTI)

of inkjet droplets ranges between 10 µm and 100 µm. Evaporation should still be limited by dif- fusion at this scale. Convection occurs in evaporating sessile droplets [12] where, in order to conserve mass, evaporating liquid is replenished by a convective... at 10 W for 5 minutes at different lo- cations in the reactor, resulting in different roughnesses. S1 showed a root mean squared (rms) roughness of ?130 nm by AFM (Digital Instruments Nanoscope III scanning probe microscope), whereas S2 had an RMS...

Talbot, E.L.; Berson, A.; Brown, P.S.; Bain, C.D.

2012-01-01T23:59:59.000Z

322

Double Diffusive Natural Convection in a Nuclear Waste Repository  

Science Conference Proceedings (OSTI)

In this study, we conduct a two-dimensional numerical analysis of double diffusive natural convection in an emplacement drift for a nuclear waste repository. In-drift heat and moisture transport is driven by combined thermal- and compositional-induced buoyancy forces. Numerical results demonstrate buoyancy-driven convective flow patterns and configurations during both repository heat-up and cool-down phases. It is also shown that boundary conditions, particularly on the drip-shield surface, have strong impacts on the in-drift convective flow and transport.

Y. Hao; J. Nitao; T.A. Buscheck; Y. Sun

2006-03-28T23:59:59.000Z

323

Mixed Convection in the VHTR in the Event of a LOFA  

Science Conference Proceedings (OSTI)

The US Department of Energy, Office of Nuclear Energy (DOE-NE) is supporting the development of a very high temperature reactor (VHTR) concept as the primary focus of it next generation nuclear power plant (NGNP) program. The VHTR is cooled by forcing helium downwards through the core into the lower plenum and out the hot duct. In the event that the coolant circulators are lost, the driving pressure drop across the core will reduce to zero and there will be the opportunity for natural circulation to occur. During the time that the circulators are powering down, the heat transfer in the core from the graphite blocks to the helium coolant will transform from turbulent forced convection to mixed convection, where buoyancy effects become important, to free or natural convection, where buoyancy is dominant. Analysis of the nature of the forced, mixed and free convection is best done using computational fluid dynamic (CFD) software that can provide fine details of the flow and heat transfer. However, CFD analysis involves approximations in the results because of the finite nature of the spatial and temporal discretizations required, the inexact nature of the turbulence models that are used and the finite precision of the computers employed. Therefore, it is necessary to validate the CFD computations. Validation is accomplished by comparing results from specific CFD computations to experimental data that have been taken specifically for the purpose of validation and that are related to the physical phenomena in question. The present report examines the flow and heat transfer parameters (dimensionless numbers) that characterize the flow and reports ranges for their values based on specific CFD studies performed for the VHTR.

Richard W. Johnson

2012-05-01T23:59:59.000Z

324

Total lightning observations of severe convection over North Texas  

E-Print Network (OSTI)

Five severe convective cells over North Texas from three separate dates were examined to determine what three dimensional, or “total” lightning data can add to the understanding of a convective cell’s intensity, propagation, and severe weather potential. Total lightning data were obtained from Vaisala Inc.’s Dallas/Fort Worth (D/FW) Lightning Detection and Ranging (LDAR) network. Radar data from two Weather Surveillance Radar – 1988 Doppler (WSR-88D) sites were used for position data and information regarding the intensity and kinematic properties of each cell. Total lightning products used by the National Weather Service Forecast Office in Fort Worth, Texas were compared to total lightning flash rate; a quantity that has been shown to be correlated to changes in cell intensity inferred from other sources, such as radar and satellite data. These products, specifically flash extent density (FED) were also compared to CG flash rate and radar derived measures from the WSR-88D sites. The results of this work show that FED and total flash rate are well correlated, with an average Pearson correlation value of 0.73, indicating that previous total flash rate results may also apply to FED. Lightning hooks, holes, and notches in FED displays indicated likely updraft regions, while appendages were observed to develop prior to deviant motion with two supercells. These results, combined with a greater update frequency provided a useful complement to radar data in the warning decision process. FED jumps were observed prior to several severe weather reports, indicating that total lightning activity may be related to updraft strength as found in past studies. However, FED jumps were sometimes observed without any associated severe event. More work is clearly needed to define what FED changes are of most importance in the short-term prediction of storm severity. The usefulness of the total lightning data on these dates was dependant upon LDAR network status and distance of the cell from the network center. The results of this study suggest that combining total flash rate trends with visual displays of FED provides the greatest added benefit to forecasters in maintaining situational awareness during warning operations.

McKinney, Christopher Michael

2008-08-01T23:59:59.000Z

325

Neutron range spectrometer  

DOE Patents (OSTI)

A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are colliminated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. 1 fig.

Manglos, S.H.

1988-03-10T23:59:59.000Z

326

The Onset of Convection in the Madden–Julian Oscillation  

Science Conference Proceedings (OSTI)

An observational study of the onset of convection in the Madden–Julian oscillation (MJO) was performed. Composites of radiosonde data from the Comprehensive Aerological Reference Data Set were constructed for an ensemble of tropical stations ...

Susan R. Kemball-Cook; Bryan C. Weare

2001-03-01T23:59:59.000Z

327

Convective Boundary Layers Driven by Nonstationary Surface Heat Fluxes  

Science Conference Proceedings (OSTI)

In this study the response of dry convective boundary layers to nonstationary surface heat fluxes is systematically investigated. This is relevant not only during sunset and sunrise but also, for example, when clouds modulate incoming solar ...

Robert van Driel; Harm J. J. Jonker

2011-04-01T23:59:59.000Z

328

On the Generation of Convectively Driven Mesohighs Aloft  

Science Conference Proceedings (OSTI)

In an attempt to determine the relative contribution of the direct incorporation of cold air (detrainment from overshooting convective cloud tops) to the production of mesohighs in the vicinity of the tropopause, two numerical simulations were ...

J. M. Fritsch; J. M. Brown

1982-11-01T23:59:59.000Z

329

Mesoscale Convective Complexes in the Western Pacific Region  

Science Conference Proceedings (OSTI)

A climatological study of mesoscale convective complexes (MCCs) during 1983–1985 over the western Pacific region (WPR), using full-disc, enhanced infrared satellite imagery from the Japanese Geostationary Meteorological Satellite is presented.

David Miller; J. M. Fritsch

1991-12-01T23:59:59.000Z

330

Mesoscale Convective Complexes over the Indian Monsoon Region  

Science Conference Proceedings (OSTI)

Full disk infrared satellite imagery from the Indian National Satellite System (INSAT) geostationary meteorological satellite was examined to determine if mesoscale convective complexes (MCCs) frequent the Indian subcontinent (ISC) region. Using ...

Arlenf G. Laing; J. Michael Fritsch

1993-05-01T23:59:59.000Z

331

Resolution Requirements for the Simulation of Deep Moist Convection  

Science Conference Proceedings (OSTI)

The spatial resolution appropriate for the simulation of deep moist convection is addressed from a turbulence perspective. To provide a clear theoretical framework for the problem, techniques for simulating turbulent flows are reviewed, and the ...

George H. Bryan; John C. Wyngaard; J. Michael Fritsch

2003-10-01T23:59:59.000Z

332

Impact of Stochastic Convection on the Ensemble Transform  

Science Conference Proceedings (OSTI)

The impact of stochastic convection on ensembles produced using the ensemble transform (ET) initial perturbation scheme is examined. This note compares the behavior of ensemble forecasts based only on initial ET perturbations with the behavior of ...

Carolyn A. Reynolds; Joao Teixeira; Justin G. McLay

2008-11-01T23:59:59.000Z

333

Tropical Convection and Precipitation Regimes in the Western United States  

Science Conference Proceedings (OSTI)

The authors have documented the relationship between tropical convection and precipitation regimes in the western United States. Circulation patterns associated with precipitation regimes are described and physical mechanisms are proposed. ...

Kingtse C. Mo; R. W. Higgins

1998-09-01T23:59:59.000Z

334

On the Relationship between Tropical Convection and Sea Surface Temperature  

Science Conference Proceedings (OSTI)

Tropical observations show convective activity increasing sharply above sea surface temperatures (SSTs) of around 26°C and then decreasing as the SST exceeds 30°C, with maximum observed SSTs of around 32°C.Although some aspects of this ...

Adrian M. Tompkins

2001-03-01T23:59:59.000Z

335

Precipitation Efficiency of Warm-Season Midwestern Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

The precipitation efficiencies for mesoscale convective systems (MCS) over the central United States are calculated. During July–September 2000 and June–September 2001, 24 MCS for which sufficient data were available occurred over or near ...

Patrick Market; Stacy Allen; Roderick Scofield; Robert Kuligowski; Arnold Gruber

2003-12-01T23:59:59.000Z

336

Convective Storm Initiation in a Moist Tropical Environment  

Science Conference Proceedings (OSTI)

Radar and satellite data from the Tropical Rainfall Measuring Mission–Large-Scale Biosphere–Atmosphere (TRMM–LBA) project have been examined to determine causes for convective storm initiation in the southwest Amazon region. The locations and ...

Maria Andrea Lima; James W. Wilson

2008-06-01T23:59:59.000Z

337

The Environments of Significant Convective Events in the Western Mediterranean  

Science Conference Proceedings (OSTI)

The environmental characteristics associated with 313 significant convective events in the western Mediterranean are investigated using radiosonde ascents made in Mallorca (Spain). The events are separated into five groups, based on the observed ...

Elisa Tudurí; Clemente Ramis

1997-06-01T23:59:59.000Z

338

Climatology of Tropical Intraseasonal Convective Anomalies: 1979–2002  

Science Conference Proceedings (OSTI)

Tropical intraseasonal convective anomalies (TICA) have a central role in subseasonal changes in the coupled ocean–atmosphere system, but the climatology of TICA events has not been properly documented. This study exploits 24 years of outgoing ...

Charles Jones; Leila M. V. Carvalho; R. Wayne Higgins; Duane E. Waliser; J-K. E. Schemm

2004-02-01T23:59:59.000Z

339

Circulation Anomalies Associated with Tropical Convection during Northern Winter  

Science Conference Proceedings (OSTI)

Lagged cross correlations between outgoing longwave radiation (OLR) and National Meteorological Center global analyses are utilized to isolate the preferred upper-level and surface circulation anomalies associated with tropical convection during ...

George N. Kiladis; Klaus M. Weickmann

1992-09-01T23:59:59.000Z

340

The Influence of Helicity on Numerically Simulated Convective Storms  

Science Conference Proceedings (OSTI)

A three-dimensional numerical cloud model is used to investigate the influence of storm-relative environmental helicity (SREH) on convective storm structure and evolution, with a particular emphasis on the identification of ambient shear profiles ...

Kelvin K. Droegemeier; Steven M. Lazarus; Robert Davies-Jones

1993-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Further Aspects of Transitions in Two-Dimensional Thermal Convection  

Science Conference Proceedings (OSTI)

In this paper we present the results of numerical investigation of a two-dimensional nonlinear set of Boussinesq equations governing Bénard–Rayleigh convection using spectral representation in the horizontal direction and finite-difference ...

Marina Zivkovi?; Ernest M. Agee

1988-12-01T23:59:59.000Z

342

Observations from Space and Thermal Convection: A Historical Perspective  

Science Conference Proceedings (OSTI)

An abbreviated historical account of the evolution of the satellite meteorology program is presented. Emphasis is placed on the importance of the satellite and its space platform for observing and studying atmospheric convection. Particular ...

Ernest M. Agee

1984-09-01T23:59:59.000Z

343

Sampling Characteristics from Isobaric Floats in a Convective Eddy Field  

Science Conference Proceedings (OSTI)

During the recent Labrador Sea Deep Convection Experiment, numerous isobaric floats were deployed. Interpretation of the quasi-Lagrangian measurements from these floats requires an understanding of any biases that may be introduced by the ...

Sonya Legg; James C. McWilliams

2002-02-01T23:59:59.000Z

344

Temperature and Salinity Variability in Heterogeneous Oceanic Convection  

Science Conference Proceedings (OSTI)

In regions of active oceanic convection, such as the Labrador Sea, small- and mesoscale spatial variability is observed in the temperature and salinity fields (T and S). Often T and S structures are “density-compensated,” with the density ...

Sonya Legg; James C. McWilliams

2000-06-01T23:59:59.000Z

345

Wavelet-Compressed Representation of Deep Moist Convection  

Science Conference Proceedings (OSTI)

The capacity of wavelets to effectively represent atmospheric processes under compression is tested by a dataset generated by a cloud-resolving model simulation of deep convective events observed during the Tropical Ocean Global Atmosphere ...

Jun-Ichi Yano; Peter Bechtold; Jean-Luc Redelsperger; Francoise Guichard

2004-06-01T23:59:59.000Z

346

Effects of Rotation on Convective Plumes from Line Segment Sources  

Science Conference Proceedings (OSTI)

Effects of rotation on finite-length line plumes are studied with a three-dimensional nonhydrostatic numerical model. Geophysical convection with this source geometry occurs, for example, as the result of fissure releases of hot hydrothermal ...

J. W. Lavelle; D. C. Smith IV

1996-06-01T23:59:59.000Z

347

Stratospheric Gravity Waves Generated by Multiscale Tropical Convection  

Science Conference Proceedings (OSTI)

The generation of gravity waves by multiscale cloud systems evolving in an initially motionless and thermodynamically uniform environment is explored using a two-dimensional cloud-system-resolving model. The simulated convection has similar depth ...

Todd P. Lane; Mitchell W. Moncrieff

2008-08-01T23:59:59.000Z

348

Organizational Modes of Mesoscale Convective Systems over Central East China  

Science Conference Proceedings (OSTI)

Composite reflectivity Doppler radar data from June to September of 2007--2010 were used to classify mesoscale convective systems (MCSs) over Central East China into seven morphologies. The morphologies included one nonlinear mode (NL) and six ...

Linlin Zheng; Jianhua Sun; Xiaoling Zhang; Changhai Liu

349

A Climatology of Fatal Convective Wind Events by Storm Type  

Science Conference Proceedings (OSTI)

There are still hundreds of casualties produced by thunderstorm hazards each year in the United States despite the many recent advances in prediction and mitigation of the effects of convective storms. Of the four most common thunderstorm hazards ...

Joseph M. Schoen; Walker S. Ashley

2011-02-01T23:59:59.000Z

350

A Linearized Convective Overturning Model for Prediction of Thunderstorm Movement  

Science Conference Proceedings (OSTI)

A linearized model of convective overturning in shear for prediction of storm propagation is presented. Good correspondence between the model and observation is found for a number of case studies of real storms. Supercell storms, however, are an ...

Adrian Marroquin; David J. Raymond

1982-01-01T23:59:59.000Z

351

Observational Analysis of the Predictability of Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

Mesoscale convective systems (MCSs) have a large influence on the weather over the central United States during the warm season by generating essential rainfall and severe weather. To gain insight into the predictability of these systems, the ...

Israel L. Jirak; William R. Cotton

2007-08-01T23:59:59.000Z

352

Equatorial Atmospheric Waves and Their Association to Convection  

Science Conference Proceedings (OSTI)

Equatorial wave systems and their relationships with convective activity are analyzed in the western and central Pacific regions during the Coupled Ocean–Atmosphere Response Experiment (COARE) intensive observation periods. The study uses ...

P. Pires; J-L. Redelsperger; J-P. Lafore

1997-06-01T23:59:59.000Z

353

A Stereo Photogrammetric Technique Applied to Orographic Convection  

Science Conference Proceedings (OSTI)

This paper describes a technique for photogrammetric analysis of stereo pairs of images that is applied to the study of orographic convection. The technique is designed for use with digital images and assumes detailed knowledge of the camera ...

Joseph A. Zehnder; Jiuxiang Hu; Anshuman Razdan

2007-06-01T23:59:59.000Z

354

Toward Convective Boundary Layer Parameterization: A Scalar Transport Module  

Science Conference Proceedings (OSTI)

Recent results from large-eddy simulations indicate that the eddy diffusivity for scalar diffusion through the top of a convective boundary layer is different from that for diffusion through the bottom. From this, one can show that the eddy ...

John C. Wyngaard

1984-06-01T23:59:59.000Z

355

An Observational Analysis of a Developing Mesoscale Convective Complex  

Science Conference Proceedings (OSTI)

Dual-Doppler radar, surface mesonet, satellite, and upper-air sounding data from the 1985 Preliminary Regional Experiment for STORM-Central field experiment are used to analyze the early growth stages of a mesoscale convective complex (MCC) that ...

Jason E. Nachamkin; Ray L. McAnelly; William R. Cotton

1994-06-01T23:59:59.000Z

356

Transitions in Shallow Convection: An Explanation for Lateral Cell Expansion  

Science Conference Proceedings (OSTI)

A generalized seven-coefficient model of two-dimensional Rayleigh-Bénard convection is presented. The model simulates successfully one means by which lateral cell expansion can occur as the value of the imposed vertical temperature difference is ...

Hai-Ru Chang; Hampton N. Shirer

1984-08-01T23:59:59.000Z

357

Positive Cloud-to-Ground Lightning in Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

We have examined the characteristics of positive cloud-to-ground lightning flashes in Mesoscale Convective Systems observed during the Oklahoma-Kansas PRE-STORM project in 1985. Lightning frequencies and patterns of ground strike locations are ...

Steven A. Rutledge; Chungu Lu; Donald R. MacGorman

1990-09-01T23:59:59.000Z

358

Physical Characterization of Tropical Oceanic Convection Observed in KWAJEX  

Science Conference Proceedings (OSTI)

The Tropical Rainfall Measuring Mission (TRMM) Kwajalein Experiment (KWAJEX) was designed to obtain an empirical physical characterization of precipitating convective clouds over the tropical ocean. Coordinated datasets were collected by three ...

Sandra E. Yuter; Robert A. Houze Jr.; Eric A. Smith; Thomas T. Wilheit; Edward Zipser

2005-04-01T23:59:59.000Z

359

Equatorial Wave Activity Derived from Fluctuations in Observed Convection  

Science Conference Proceedings (OSTI)

The spectrum of equatorial wave activity propagating vertically into the stratosphere is calculated from high-resolution imagery of the global convective pattern. Synoptic Global Cloud Imagery (GCI), constructed from six satellites simultaneously ...

John W. Bergman; Murry L. Salby

1994-12-01T23:59:59.000Z

360

Observed Evolution of Tropical Deep Convective Events and Their Environment  

Science Conference Proceedings (OSTI)

Using a compositing technique, the temporal progression of tropical convective systems and the mean atmospheric state in their vicinity is constructed from a time series of geostationary satellite and operational rawinsonde data. The technique ...

Steven C. Sherwood; Ralph Wahrlich

1999-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Analytical Parameterizations of Diffusion: The Convective Boundary Layer  

Science Conference Proceedings (OSTI)

A brief review is made of data bases which have been used for developing diffusion parameterizations for the convective boundary layer (CBL). A variety of parameterizations for lateral and vertical dispersion, ?y and ?z, are surveyed; some of ...

Gary A. Briggs

1985-11-01T23:59:59.000Z

362

The “Footprint” under a Decaying Tropical Mesoscale Convective System  

Science Conference Proceedings (OSTI)

On 10 February 1993, during the Tropical Ocean Global Atmosphere Coupled Ocean–Atmosphere Response Experiment, the two NOAA WP-3Ds and the NCAR Electra flew under the anvil region of a decaying mesoscale convective system (MCS). Satellite and ...

Mark F. Geldmeier; Gary M. Barnes

1997-11-01T23:59:59.000Z

363

Diabatic Divergence Profiles in Western Pacific Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

Heating in the atmosphere can be expressed as diabatic divergence ?d, which is nearly equal to the actual horizontal divergence ? in tropical convection. High-quality ? profile measurements from airborne Doppler radar “purls” in ten mesoscale ...

Brian E. Mapes; Robert A. Houze Jr.

1995-05-01T23:59:59.000Z

364

Satellite and Radar Survey of Mesoscale Convective System Development  

Science Conference Proceedings (OSTI)

An investigation of several hundred mesoscale convective systems (MCSs) during the warm seasons (April–August) of 1996–98 is presented. Circular and elongated MCSs on both the large and small scales were classified and analyzed in this study ...

Israel L. Jirak; William R. Cotton; Ray L. McAnelly

2003-10-01T23:59:59.000Z

365

Wintertime Convection in a Gulf stream Warm Core Ring  

Science Conference Proceedings (OSTI)

Wintertime convection creates deep mixed layers which determine the water mass characteristics and potential vorticity for waters in the main pycnocline of the world ocean. Diabatic cooling is most intense in the Northern Hemisphere near the ...

Terrence M. Joyce; Marvel C. Stalcup

1985-08-01T23:59:59.000Z

366

Observations of Vertical Wind Shear Heterogeneity in Convective Boundary Layers  

Science Conference Proceedings (OSTI)

Dual-Doppler wind syntheses from mobile radar observations obtained during the International H2O Project document some of the spatial variability of vertical wind profiles in convective boundary layers. Much of the variability of popular ...

Paul Markowski; Yvette Richardson

2007-03-01T23:59:59.000Z

367

Frontogenesis in the Presence of Small Stability to Slantwise Convection  

Science Conference Proceedings (OSTI)

It is often observed that, despite the existence of near neutrality to slantwise convection, rainbands and snowbands can persist for long periods with narrow intense updrafts producing large quantities of precipitation in many cases. This is ...

A. J. Thorpe; K. A. Emanuel

1985-09-01T23:59:59.000Z

368

Survey and evaluation of techniques to augment convective heat transfer  

E-Print Network (OSTI)

This report presents a survey and evaluation of the numerous techniques which have been shown to augment convective heat transfer. These techniques are: surface promoters, including roughness and treatment; displaced ...

Bergles A. E.

1965-01-01T23:59:59.000Z

369

Multiple Convection Patterns and Thermohaline Flow in an Idealized OGCM  

Science Conference Proceedings (OSTI)

This paper investigates how multiple steady states arise in an ocean general circulation model, caused by the fact that many different convection patterns can be stable under the same surface boundary conditions. Two alternative boundary ...

Stefan Rahmstorf

1995-12-01T23:59:59.000Z

370

Factors for the Simulation of Convectively Coupled Kelvin Waves  

Science Conference Proceedings (OSTI)

This study investigates the major factors for the realistic simulation of convectively coupled Kelvin waves (CCKWs) using the National Centers for Environmental Prediction (NCEP) Climate Forecast System (CFS) models. CFS simulations employing ...

Kyong-Hwan Seo; Jin-Ho Choi; Sang-Dae Han

2012-05-01T23:59:59.000Z

371

The Tropical Convective Spectrum. Part I: Archetypal Vertical Structures  

Science Conference Proceedings (OSTI)

A taxonomy of tropical convective and stratiform vertical structures is constructed through cluster analysis of 3 yr of Tropical Rainfall Measuring Mission (TRMM) “warm-season” (surface temperature greater than 10°C) precipitation radar (PR) ...

Dennis J. Boccippio; Walter A. Petersen; Daniel J. Cecil

2005-07-01T23:59:59.000Z

372

Convective Precursors and Predictability in the Tropical Western Pacific  

Science Conference Proceedings (OSTI)

Conditions leading to convective outbreak in the Tropics are investigated by multivariate analysis of sounding and satellite data from the tropical western Pacific area. Circumstances that make the prediction problem difficult are discussed and ...

Steven C. Sherwood

1999-12-01T23:59:59.000Z

373

An Observational Study of Derecho-Producing Convective Systems  

Science Conference Proceedings (OSTI)

This study identifies the common large-scale environments associated with the development of derecho- producing convective systems (DCSs) from a large number of events. Patterns are identified using statistical clustering of the 500-mb ...

Michael C. Coniglio; David J. Stensrud; Michael B. Richman

2004-04-01T23:59:59.000Z

374

A Large Eddy Simulation Intercomparison Study of Shallow Cumulus Convection  

Science Conference Proceedings (OSTI)

This paper reports an intercomparison study on undisturbed trade wind cumulus convection under steady-state conditions as observed during the Barbados Oceanographic and Meteorological Experiment (BOMEX) with 10 large eddy simulation (LES) models. ...

A. Pier Siebesma; Christopher S. Bretherton; Andrew Brown; Andreas Chlond; Joan Cuxart; Peter G. Duynkerke; Hongli Jiang; Marat Khairoutdinov; David Lewellen; Chin-Hoh Moeng; Enrique Sanchez; Bjorn Stevens; David E. Stevens

2003-05-01T23:59:59.000Z

375

Analysis of Convection and Its Association with African Easterly Waves  

Science Conference Proceedings (OSTI)

The association between convection and African easterly wave (AEW) activity over tropical Africa and the tropical Atlantic during the boreal summer is examined using satellite brightness temperature (TB) and ECMWF reanalysis datasets. Spectral ...

Ademe Mekonnen; Chris D. Thorncroft; Anantha R. Aiyyer

2006-10-01T23:59:59.000Z

376

Convection-Evaporation Feedback in the Equatorial pacific  

Science Conference Proceedings (OSTI)

The coupling between convection and surface evaporation is investigated to assess the importance of evaporative cooling in regulating the tropical sea surface temperature. It is found that such a coupling is scale dependent. On timescales of ...

Guang Jun Zhang; V. Ramanathan; Michael J. McPhaden

1995-12-01T23:59:59.000Z

377

Eddy Modulation of Air–Sea Interaction and Convection  

Science Conference Proceedings (OSTI)

Eddy modulation of the air–sea interaction and convection that occurs in the process of mode water formation is analyzed in simulations of a baroclinically unstable wind- and buoyancy-driven jet. The watermass transformation analysis of Walin is ...

Ivana Cerove?ki; John Marshall

2008-01-01T23:59:59.000Z

378

Convective Episodes in the East-Central United States  

Science Conference Proceedings (OSTI)

Nine years of composited radar data are investigated to assess the presence of organized convective episodes in the east-central United States. In the eastern United States, the afternoon maximum in thunderstorms is ubiquitous over land. However, ...

Matthew D. Parker; David A. Ahijevych

2007-11-01T23:59:59.000Z

379

Meso- and Submesoscale Structure of a Convecting Field  

Science Conference Proceedings (OSTI)

Intensive data collection in the region of the Labrador Sea northwest of former Ocean Weather Station Bravo during the winter of 1998 allowed examination of the meso- and submesoscale structure during active convection. Data used include ...

Elizabeth L. Steffen; Eric A. D'Asaro

2004-01-01T23:59:59.000Z

380

Circulations between Mesoscale Convective Systems along a Cold Front  

Science Conference Proceedings (OSTI)

A frontal squall line that passed over the central United States on 14–15 June 1985 consisted of several primary mesoscale convective systems (MCSs) with a prominent gap (several hundred kilometers wide) between two of them over central Kansas ...

Richard H. Johnson; Barbara D. Miner; Paul E. Ciesielski

1995-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Deep Convective System Evolution over Africa and the Tropical Atlantic  

Science Conference Proceedings (OSTI)

In the tropical African and neighboring Atlantic region there is a strong contrast in the properties of deep convection between land and ocean. Here, satellite radar observations are used to produce a composite picture of the life cycle of ...

Joanna M. Futyan; Anthony D. Del Genio

2007-10-01T23:59:59.000Z

382

Synoptic Wave Perturbations and Convective Systems over Equatorial Africa  

Science Conference Proceedings (OSTI)

Spectral analysis of the outgoing longwave radiation (OLR) time series over equatorial Africa reveals large oscillations of the convection with periods of between 3 and 6 days. In March and April, when the intertropical convergence zone (ITCZ) ...

Hanh Nguyen; Jean-Philippe Duvel

2008-12-01T23:59:59.000Z

383

Synoptic Mapping of Convective Structure from Undersampled Satellite Observations  

Science Conference Proceedings (OSTI)

Climate properties regulated by convection, such as water vapor, cloud cover, and related distributions, are undersampled in asynoptic data from an individual orbiting platform, which must therefore be restricted to time-mean distributions. A ...

Murry Salby; Fabrizio Sassi

2001-05-01T23:59:59.000Z

384

Sensitivity of Boundary-layer and Deep Convective Cloud Simulations...  

NLE Websites -- All DOE Office Websites (Extended Search)

convective clouds using a cloud resolving model (CRM). A CRM usually uses a vertical grid spacing less than 100 m to simulate boundary layer clouds such as shallow cumuli and...

385

Transient Environmental Sensitivities of Explicitly Simulated Tropical Convection  

Science Conference Proceedings (OSTI)

A three-dimensional cloud-resolving model, maintained in a statistically steady convecting state by tropics-like forcing, is subjected to sudden (10 min) stimuli consisting of horizontally homogeneous temperature and/or moisture sources with ...

Stefan N. Tulich; Brian E. Mapes

2010-04-01T23:59:59.000Z

386

Two-Zone Convective Scaling of Diffusion in Complex Terrain  

Science Conference Proceedings (OSTI)

A “two-zone” convective scaling equation is developed that allows for a step change in scaling parameters. The results of the Lompoc Valley Diffusion Experiment, conducted at coastal site in California under variable cloud cover, are compared to ...

C. E. Skupniewicz

1994-05-01T23:59:59.000Z

387

A Stochastic Model for the Transition to Strong Convection  

Science Conference Proceedings (OSTI)

A simple stochastic model is designed and analyzed in order to further understand the transition to strong convection. The transition has been characterized recently in observational data by an array of statistical measures, including (i) a sharp ...

Samuel N. Stechmann; J. David Neelin

2011-12-01T23:59:59.000Z

388

Gravity Waves and Convection in Colorado during July 1983  

Science Conference Proceedings (OSTI)

In order to gain insight into the complex dynamics of a convective system interacting with a gravity wave train, we have carried out an experiment in northeast Colorado during July and August, 1983, utilizing data from several program areas in ...

F. Einaudi; W. L. Clark; J. L. Green; T. E. VanZandt; D. Fua

1987-06-01T23:59:59.000Z

389

An Investigation of Turbulence Generation Mechanisms above Deep Convection  

Science Conference Proceedings (OSTI)

An investigation of the generation of turbulence above deep convection is presented. This investigation is motivated by an encounter between a commercial passenger aircraft and severe turbulence above a developing thunderstorm near Dickinson, ...

Todd P. Lane; Robert D. Sharman; Terry L. Clark; Hsiao-Ming Hsu

2003-05-01T23:59:59.000Z

390

Dynamic Radiative–Convective Equilibria Using GCM Column Physics  

Science Conference Proceedings (OSTI)

The behavior of a GCM column physics package in a nonrotating, doubly periodic, homogeneous setting with prescribed SSTs is examined. This radiative–convective framework is proposed as a useful tool for studying some of the interactions between ...

Isaac M. Held; Ming Zhao; Bruce Wyman

2007-01-01T23:59:59.000Z

391

Numerical Modeling of Gravity Wave Generation by Deep Tropical Convection  

Science Conference Proceedings (OSTI)

Although convective clouds are known to generate internal gravity waves, the mechanisms responsible are not well understood. The present study seeks to clarify the dynamics of wave generation using a high-resolution numerical model of deep ...

Todd P. Lane; Michael J. Reeder; Terry L. Clark

2001-05-01T23:59:59.000Z

392

RESEARCH CAMPAIGN: The Convective and Orographically Induced Precipitation Study  

Science Conference Proceedings (OSTI)

The international field campaign called the Convective and Orographically-induced Precipitation Study (COPS) took place from June to August 2007 in southwestern Germany/eastern France. The overarching goal of COPS is to advance the quality of ...

Volker Wulfmeyer; Andreas Behrendt; Hans-Stefan Bauer; Christoph Kottmeier; Ulrich Corsmeier; Alan Blyth; George Craig; Ulrich Schumann; Martin Hagen; Susanne Crewell; Paolo Di Girolamo; Cyrille Flamant; Mark Miller; Andrea Montani; Stephen Mobbs; Evelyne Richard; Mathias W. Rotach; Marco Arpagaus; Herman Russchenberg; Peter Schlüssel; Marianne König; Volker Gärtner; Reinhold Steinacker; Manfred Dorninger; David D. Turner; Tammy Weckwerth; Andreas Hense; Clemens Simmer

2008-10-01T23:59:59.000Z

393

Evaluation of Parametric Assumptions for Shallow Cumulus Convection  

Science Conference Proceedings (OSTI)

A large-eddy simulation (LES) model has been utilized to study nonprecipitating Shallow Convective clouds such as observed during the undisturbed BOMEX period in the trade wind areas. By choosing a realistic large-scale forcing the authors have ...

A. P. Siebesma; J. W. M. Cuijpers

1995-03-01T23:59:59.000Z

394

Fluctuations in an Equilibrium Convective Ensemble. Part I: Theoretical Formulation  

Science Conference Proceedings (OSTI)

To provide a theoretical basis for stochastic parameterization of cumulus convection, the equilibrium fluctuations of a field of cumulus clouds under homogeneous large-scale forcing are derived statistically, using the Gibbs canonical ensemble ...

George C. Craig; Brenda G. Cohen

2006-08-01T23:59:59.000Z

395

Equatorial Convectively Coupled Waves in a Simple Multicloud Model  

Science Conference Proceedings (OSTI)

Linear stability results for the multicloud model recently developed by the authors on an equatorial beta plane are presented here. The linearized equations, about a realistic radiative–convective equilibrium (RCE) are projected in the meridional ...

Boualem Khouider; Andrew J. Majda

2008-11-01T23:59:59.000Z

396

Lidar Observations of Banded Convection during BLX83  

Science Conference Proceedings (OSTI)

Lidar observations of clear-air convection during the 1983 Boundary Layer Experiment (BLX83) reveal the presence of elongated, parallel regions of updrafts marked by enhanced aerosol backscattering. These linear (banded) aerosol structures were ...

R. A. Ferrare; J. L. Schols; E. W. Eloranta; R. Coulter

1991-03-01T23:59:59.000Z

397

Forecasting the Maintenance of Quasi-Linear Mesoscale Convective Systems  

Science Conference Proceedings (OSTI)

The problem of forecasting the maintenance of mesoscale convective systems (MCSs) is investigated through an examination of observed proximity soundings. Furthermore, environmental variables that are statistically different between mature and ...

Michael C. Coniglio; Harold E. Brooks; Steven J. Weiss; Stephen F. Corfidi

2007-06-01T23:59:59.000Z

398

Spectral Characteristics of the Convective Boundary Layer Over Uneven Terrain  

Science Conference Proceedings (OSTI)

The paper describes a convective boundary layer experiment conducted in April 1978 at the Boulder Atmospheric Observatory, and examines the spectral behavior of wind velocity and temperature from the Observatory's 300 m tower, from aircraft ...

J. C. Kaimal; R. A. Eversole; D. H. Lenschow; B. B. Stankov; P. H. Kahn; J. A. Businger

1982-05-01T23:59:59.000Z

399

The AROME-France Convective-Scale Operational Model  

Science Conference Proceedings (OSTI)

After six years of scientific, technical developments and meteorological validation, the Application of Research to Operations at Mesoscale (AROME-France) convective-scale model became operational at Météo-France at the end of 2008. This paper ...

Y. Seity; P. Brousseau; S. Malardel; G. Hello; P. Bénard; F. Bouttier; C. Lac; V. Masson

2011-03-01T23:59:59.000Z

400

Structure of Large-Scale Convective Anomalies over Tropical Oceans  

Science Conference Proceedings (OSTI)

Geographical variations in the variance and cross-correlation of monthly mean sea surface temperature (SST), outgoing longwave radiation (OLR, a proxy for deep convection and vertical motion), and convergence of winds at the surface and at 850 mb ...

David S. Gutzler; Tamara M. Wood

1990-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Overview of the Convection and Moisture Experiment (CAMEX)  

Science Conference Proceedings (OSTI)

This paper presents an overview of the Convection and Moisture Experiment (CAMEX), including the field operations, aircraft platforms and missions, instrumentation, and data acquired during 1998 and 2001 field campaigns. A total of eight tropical ...

Ramesh Kakar; Michael Goodman; Robbie Hood; Anthony Guillory

2006-01-01T23:59:59.000Z

402

Organizational Modes of Mesoscale Convective Systems over Central East China  

Science Conference Proceedings (OSTI)

Composite reflectivity Doppler radar data from June to September of 2007–2010 were used to classify mesoscale convective systems (MCSs) over central east China into seven morphologies. The morphologies included one nonlinear mode (NL) and six ...

Linlin Zheng; Jianhua Sun; Xiaoling Zhang; Changhai Liu

2013-10-01T23:59:59.000Z

403

Large-Eddy Simulation of the Convective Atmospheric Boundary Layer  

Science Conference Proceedings (OSTI)

Large-eddy simulations of a free convective atmospheric boundary layer with an overlying capping inversion are considered. Attention is given to the dependence of the results upon the various factors influencing the simulation: the subgrid model, ...

P. J. Mason

1989-06-01T23:59:59.000Z

404

Simulated Convective Lines with Leading Precipitation. Part I: Governing Dynamics  

Science Conference Proceedings (OSTI)

This article, the first of two describing a study in which the authors used idealized numerical simulations to investigate convective lines with leading precipitation, addresses the dynamics governing the systems' structures and individual air ...

Matthew D. Parker; Richard H. Johnson

2004-07-01T23:59:59.000Z

405

Extreme Helicity and Intense Convective Towers in Hurricane Bonnie  

Science Conference Proceedings (OSTI)

Helicity was calculated in Hurricane Bonnie (1998) using tropospheric-deep dropsonde soundings from the NASA Convection and Moisture Experiment. Large helicity existed downshear of the storm center with respect to the ambient vertical wind shear. ...

John Molinari; David Vollaro

2008-11-01T23:59:59.000Z

406

Influence of Bulk Convection on Freckle Formation in Castings  

Science Conference Proceedings (OSTI)

compartments, a hot zone and a cold zone as shown in Figure l(a) below. A baffle is used to .... that the bulk convection cell will not distort the flow at the inlet.

407

Representing Convective Organization in Prediction Models by a Hybrid Strategy  

Science Conference Proceedings (OSTI)

The mesoscale organization of precipitating convection is highly relevant to next-generation global numerical weather prediction models, which will have an intermediate horizontal resolution (grid spacing about 10 km). A primary issue is how to ...

Mitchell W. Moncrieff; Changhai Liu

2006-12-01T23:59:59.000Z

408

A Stochastic Parameterization for Deep Convection Based on Equilibrium Statistics  

Science Conference Proceedings (OSTI)

A stochastic parameterization scheme for deep convection is described, suitable for use in both climate and NWP models. Theoretical arguments and the results of cloud-resolving models are discussed in order to motivate the form of the scheme. In ...

R. S. Plant; G. C. Craig

2008-01-01T23:59:59.000Z

409

The Kain–Fritsch Convective Parameterization: An Update  

Science Conference Proceedings (OSTI)

Numerous modifications to the Kain–Fritsch convective parameterization have been implemented over the last decade. These modifications are described, and the motivating factors for the changes are discussed. Most changes were inspired by feedback ...

John S. Kain

2004-01-01T23:59:59.000Z

410

Another Look at the Thermodynamic Equation For Deep Convection  

Science Conference Proceedings (OSTI)

The study considers deep moist convection involving only a liquid-vapor phase change. An alternative form of the classical thermodynamic equation for reversible saturated flow is derived. Four approximate forms of this equation are obtained and ...

Frank B. Lipps; Richard S. Hemler

1980-01-01T23:59:59.000Z

411

Reply to “Comments on ‘Preconditioning Deep Convection with Cumulus Congestus’”  

Science Conference Proceedings (OSTI)

In his comment, D. M. Schultz asked for clarification concerning (i) the validity of the results of C. Hohenegger and B. Stevens for the development of convection over the midlatitudes and (ii) the exact meaning and computation of the term “...

Cathy Hohenegger; Bjorn Stevens

2013-12-01T23:59:59.000Z

412

A Forced Gravity Wave Model of Serf-Organizing Convection  

Science Conference Proceedings (OSTI)

A two-dimensional, hydrostatic, nonrotating numerical model with a cumulus paramelerizafion is developed to study the early stages of mesozcale convective systems. Amplifying, forced gravity waves occur when peneirative downdrafts are present. ...

David J. Raymond

1987-12-01T23:59:59.000Z

413

Upscale Effects of Deep Convection during the North American Monsoon  

Science Conference Proceedings (OSTI)

The ability of deep monsoon convection to influence the larger-scale circulation over North America is investigated for a 6-day long case study during the 2006 North American monsoon season. Results from Rossby wave ray tracing and numerical ...

David J. Stensrud

414

Processes of Hydrometeor Development in Oklahoma Convective Clouds  

Science Conference Proceedings (OSTI)

This study employs in situ measurements to examine cloud conditions in which hydrometeors develop in mature Oklahoma convective clouds and to develop hypotheses as to how they formed. The measurements were made from penetrations on six days using ...

Andrew J. Heymsfield; Mark R. Hjelmfelt

1984-10-01T23:59:59.000Z

415

The Role of Convective Instability in an Oklahoma Squall Line  

Science Conference Proceedings (OSTI)

Previous investigations of the 8 June 1966 National Severe Storms Laboratory case show that mesoscale lift from an “inland sea breeze” due to a newly formed temperature gradient preceded convection. Using additional surface data, this case was ...

Frank P. Colby Jr.

1980-09-01T23:59:59.000Z

416

Comparing Model-produced Convective Cloudiness with Observations  

Science Conference Proceedings (OSTI)

Convective cloudiness generated by a cumulus parameterization scheme of a large-scale numerical weather prediction model was compared with analyses of clouds observed by geosynchronous satellites. The comparisons were performed over an equatorial ...

D. C. Norquist; C. Yang

1992-05-01T23:59:59.000Z

417

Midlevel Cyclonic Vortices Generated by Mesoseale Convective Systems  

Science Conference Proceedings (OSTI)

Despite the large number of convective systems that occur over the central United States every year, there are typically only a few well-defined, midlevel vortices apparent in satellite imagery after the overlying anvil debris from some ...

Diana L. Bartels; Robert A. Maddox

1991-01-01T23:59:59.000Z

418

Convectively Driven Mixing in the Bottom Boundary Layer  

Science Conference Proceedings (OSTI)

Closely spaced vertical profiles through the bottom boundary layer over a sloping continental shelf during relaxation from coastal upwelling reveal structure that is consistent with convectively driven mixing. Parcels of fluid were observed ...

J. N. Moum; A. Perlin; J. M. Klymak; M. D. Levine; T. Boyd; P. M. Kosro

2004-10-01T23:59:59.000Z

419

High Rayleigh number turbulent convection in a gas near the gas-liquid critical point  

E-Print Network (OSTI)

$SF_6$ in the vicinity of its critical point was used to study turbulent convection up to exceptionally high Rayleigh numbers, $Ra$, (up to $5\\cdot 10^{14}$) and to verify for the first time the generalized scaling laws for the heat transport and the large scale circulation velocity as a function of $Ra$ and the Prandtl number, $Pr$, in very wide range of these parameters. The both scaling laws obtained are consistent with theoretical predictions by B.Shraiman and E.Siggia, Phys. Rev. {\\bf A 42}, 3650 (1990).

Sh. Ashkenazi; V. Steinberg

1999-03-16T23:59:59.000Z

420

An experimental study of free convection in compound parabolic concentrator (CPC) cavities  

SciTech Connect

An experimental study of the free convection heat transfer between the cylindrical absorber and the flat top of a compound parabolic concentrator (CPC) is described. Results are obtained for a range of absorber temperatures and four CPC cavity heights. For similar conditions of operating temperature, the heat transfer from a cylinder in free air is about 30 to 50 percent higher than in a CPC cavity. Two correlations for Nusselt and Grashof numbers have been obtained using the equivalent length and the cavity height as the characteristic length of the system.

Chew, T.C.; Wijeysundera, N.E.; Tay, A.O.

1988-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Range imaging laser radar  

SciTech Connect

A laser source is operated continuously and modulated periodically (typicy sinusoidally). A receiver imposes another periodic modulation on the received optical signal, the modulated signal being detected by an array of detectors of the integrating type. Range to the target determined by measuring the phase shift of the intensity modulation on the received optical beam relative to a reference. The receiver comprises a photoemitter for converting the reflected, periodically modulated, return beam to an accordingly modulated electron stream. The electron stream is modulated by a local demodulation signal source and subsequently converted back to a photon stream by a detector. A charge coupled device (CCD) array then averages and samples the photon stream to provide an electrical signal in accordance with the photon stream.

Scott, Marion W. (Albuquerque, NM)

1990-01-01T23:59:59.000Z

422

Handbook of single-phase convective heat transfer  

Science Conference Proceedings (OSTI)

This book presents a comprehensive collection of convective heat transfer basics, methods of calculations, tables, charts and design parameters involving single-phase flows - the most commonly experienced mode in heat transfer problems. Topics covered include natural and forced convection under a wise variety of design conditions, such as ducts, crossflows, turbulent conditions, transitional states, curved and coiled ducts, over rods in metals and through bends, valves and fittings. The book provides sections on radiation interaction and fouling conditions.

Kakac, S.; Shah, R.K.; Aung, W.

1987-01-01T23:59:59.000Z

423

SCALE ANALYSIS OF CONVECTIVE MELTING WITH INTERNAL HEAT GENERATION  

SciTech Connect

Using a scale analysis approach, we model phase change (melting) for pure materials which generate internal heat for small Stefan numbers (approximately one). The analysis considers conduction in the solid phase and natural convection, driven by internal heat generation, in the liquid regime. The model is applied for a constant surface temperature boundary condition where the melting temperature is greater than the surface temperature in a cylindrical geometry. We show the time scales in which conduction and convection heat transfer dominate.

John Crepeau

2011-03-01T23:59:59.000Z

424

POSSIBLE SOLAR CYCLE VARIATIONS IN THE CONVECTION ZONE  

E-Print Network (OSTI)

Abstract. Using data from the Global Oscillations Network Group (GONG) that covers the period from 1995 to 1998 we study the change in frequencies of solar oscillations with solar activity. From these frequencies we attempt to determine any possible variation in solar structure with solar activity. We do not find any evidence of a change in the convection zone depth or extent of overshoot below the convection zone during the solar cycle.

Sarbani Basu; H. M. Antia

2008-01-01T23:59:59.000Z

425

Lunar Laser Ranging Science  

E-Print Network (OSTI)

Analysis of Lunar Laser Ranging (LLR) data provides science results: gravitational physics and ephemeris information from the orbit, lunar science from rotation and solid-body tides, and Earth science. Sensitive tests of gravitational physics include the Equivalence Principle, limits on the time variation of the gravitational constant G, and geodetic precession. The equivalence principle test is used for an accurate determination of the parametrized post-Newtonian (PPN) parameter \\beta. Lunar ephemerides are a product of the LLR analysis used by current and future spacecraft missions. The analysis is sensitive to astronomical parameters such as orbit, masses and obliquity. The dissipation-caused semimajor axis rate is 37.9 mm/yr and the associated acceleration in orbital longitude is -25.7 ''/cent^2, dominated by tides on Earth with a 1% lunar contribution. Lunar rotational variation has sensitivity to interior structure, physical properties, and energy dissipation. The second-degree lunar Love numbers are detected; k_2 has an accuracy of 11%. Lunar tidal dissipation is strong and its Q has a weak dependence on tidal frequency. A fluid core of about 20% the Moon's radius is indicated by the dissipation data. Evidence for the oblateness of the lunar fluid-core/solid-mantle boundary is getting stronger. This would be independent evidence for a fluid lunar core. Moon-centered coordinates of four retroreflectors are determined. Station positions and motion, Earth rotation variations, nutation, and precession are determined from analyses. Extending the data span and improving range accuracy will yield improved and new scientific results. Adding either new retroreflectors or precise active transponders on the Moon would improve the accuracy of the science results.

James G. Williams; Dale H. Boggs; Slava G. Turyshev; J. Todd Ratcliff

2004-11-18T23:59:59.000Z

426

COMPARISON OF CONVECTIVE OVERSHOOTING MODELS AND THEIR IMPACT ON ABUNDANCES FROM INTEGRATED LIGHT SPECTROSCOPY OF YOUNG (<3 Gyr) STAR CLUSTERS  

Science Conference Proceedings (OSTI)

As part of an ongoing program to measure detailed chemical abundances in nearby galaxies, we use a sample of young- to intermediate-age clusters in the Large Magellanic Cloud with ages of 10 Myr-2 Gyr to evaluate the effect of isochrone parameters, specifically core convective overshooting, on Fe abundance results from high-resolution, integrated light spectroscopy. In this work we also obtain fiducial Fe abundances from high-resolution spectroscopy of the cluster individual member stars. We compare the Fe abundance results for the individual stars to the results from isochrones and integrated light spectroscopy to determine whether isochrones with convective overshooting should be used in our integrated light analysis of young- to intermediate-age (10 Myr-3 Gyr) star clusters. We find that when using the isochrones from the Teramo group, we obtain more accurate results for young- and intermediate-age clusters over the entire age range when using isochrones without convective overshooting. While convective overshooting is not the only uncertain aspect of stellar evolution, it is one of the most readily parameterized ingredients in stellar evolution models, and thus important to evaluate for the specific models used in our integrated light analysis. This work demonstrates that our method for integrated light spectroscopy of star clusters can provide unique tests for future constraints on stellar evolution models of young- and intermediate-age clusters.

Colucci, Janet E.; Bernstein, Rebecca A., E-mail: jcolucci@ucolick.org, E-mail: rab@ucolick.org [Department of Astronomy and Astrophysics, 1156 High Street, UCO/Lick Observatory, University of California, Santa Cruz, CA 95064 (United States)

2012-04-20T23:59:59.000Z

427

TURBULENT CONVECTION MODEL IN THE OVERSHOOTING REGION. II. THEORETICAL ANALYSIS  

SciTech Connect

Turbulent convection models (TCMs) are thought to be good tools to deal with the convective overshooting in the stellar interior. However, they are too complex to be applied to calculations of stellar structure and evolution. In order to understand the physical processes of the convective overshooting and to simplify the application of TCMs, a semi-analytic solution is necessary. We obtain the approximate solution and asymptotic solution of the TCM in the overshooting region, and find some important properties of the convective overshooting. (1) The overshooting region can be partitioned into three parts: a thin region just outside the convective boundary with high efficiency of turbulent heat transfer, a power-law dissipation region of turbulent kinetic energy in the middle, and a thermal dissipation area with rapidly decreasing turbulent kinetic energy. The decaying indices of the turbulent correlations k, u{sub r}'T'-bar, and T'T'-bar are only determined by the parameters of the TCM, and there is an equilibrium value of the anisotropic degree {omega}. (2) The overshooting length of the turbulent heat flux u{sub r}'T'-bar is about 1H{sub k} (H{sub k} = |dr/dln k|). (3) The value of the turbulent kinetic energy at the convective boundary k{sub C} can be estimated by a method called the maximum of diffusion. Turbulent correlations in the overshooting region can be estimated by using k{sub C} and exponentially decreasing functions with the decaying indices.

Zhang, Q. S.; Li, Y., E-mail: zqs@ynao.ac.cn, E-mail: ly@ynao.ac.cn [National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, P.O. Box 110, Kunming 650011 (China)

2012-05-01T23:59:59.000Z

428

AN ANALYTIC RADIATIVE-CONVECTIVE MODEL FOR PLANETARY ATMOSPHERES  

Science Conference Proceedings (OSTI)

We present an analytic one-dimensional radiative-convective model of the thermal structure of planetary atmospheres. Our model assumes that thermal radiative transfer is gray and can be represented by the two-stream approximation. Model atmospheres are assumed to be in hydrostatic equilibrium, with a power-law scaling between the atmospheric pressure and the gray thermal optical depth. The convective portions of our models are taken to follow adiabats that account for condensation of volatiles through a scaling parameter to the dry adiabat. By combining these assumptions, we produce simple, analytic expressions that allow calculations of the atmospheric-pressure-temperature profile, as well as expressions for the profiles of thermal radiative flux and convective flux. We explore the general behaviors of our model. These investigations encompass (1) worlds where atmospheric attenuation of sunlight is weak, which we show tend to have relatively high radiative-convective boundaries; (2) worlds with some attenuation of sunlight throughout the atmosphere, which we show can produce either shallow or deep radiative-convective boundaries, depending on the strength of sunlight attenuation; and (3) strongly irradiated giant planets (including hot Jupiters), where we explore the conditions under which these worlds acquire detached convective regions in their mid-tropospheres. Finally, we validate our model and demonstrate its utility through comparisons to the average observed thermal structure of Venus, Jupiter, and Titan, and by comparing computed flux profiles to more complex models.

Robinson, Tyler D. [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195-1580 (United States); Catling, David C., E-mail: robinson@astro.washington.edu [Department of Earth and Space Sciences, University of Washington, Box 351310, Seattle, WA 98195-1310 (United States)

2012-09-20T23:59:59.000Z

429

Applicability of Large-Scale Convection and Condensation Parameterization to Meso-?-Scale HIRLAM: A Case Study of a Convective Event  

Science Conference Proceedings (OSTI)

This paper presents a case study of a single cold air outbreak event with widespread convective precipitation over southern Finland on 25 May 2001. The purpose of the study is to investigate the applicability of the convection and condensation ...

Sami Niemelä; Carl Fortelius

2005-08-01T23:59:59.000Z

430

The Impact of Large-Scale Forcing on Skill of Simulated Convective Initiation and Upscale Evolution with Convection-Allowing Grid Spacings in the WRF  

Science Conference Proceedings (OSTI)

A set of mesoscale convective systems (MCSs) was simulated using the Weather Research and Forecasting model with 3-km grid spacing to investigate the skill at predicting convective initiation and upscale evolution into an MCS. Precipitation was ...

Jeffrey D. Duda; William A. Gallus Jr.

2013-08-01T23:59:59.000Z

431

Atlantic Tropical Cyclogenesis: A Three-Way Interaction between an African Easterly Wave, Diurnally Varying Convection, and a Convectively Coupled Atmospheric Kelvin Wave  

Science Conference Proceedings (OSTI)

This paper explores a three-way interaction between an African easterly wave (AEW), the diurnal cycle of convection over the Guinea Highlands (GHs), and a convectively coupled atmospheric equatorial Kelvin wave (CCKW). These interactions resulted ...

Michael J. Ventrice; Christopher D. Thorncroft; Matthew A. Janiga

2012-04-01T23:59:59.000Z

432

A Numerical Sensitivity Study on the Impact of Soil Moisture on Convection-Related Parameters and Convective Precipitation over Complex Terrain  

Science Conference Proceedings (OSTI)

The impact of soil moisture on convection-related parameters and convective precipitation over complex terrain is studied by numerical experiments using the nonhydrostatic Consortium for Small-Scale Modeling (COSMO) model. For 1 day of the ...

Christian Barthlott; Norbert Kalthoff

2011-12-01T23:59:59.000Z

433

An Analytical Study of the Dependence of Orientation and Propagation of the Arabian Sea Convection Bands on Wind Shear, Static Stability, and Preexisting Convection  

Science Conference Proceedings (OSTI)

Organization of convection into bands over the Arabian Sea during a monsoon onset was studied analytically. Observed vertical profiles of temperature, moisture, and wind velocity were used as base states by a linear model of convection to deduce ...

John R. Roadcap; Gandikota V. Rao

1993-06-01T23:59:59.000Z

434

Interannual to Diurnal Variations in Tropical and Subtropical Deep Convective Clouds and Convective Overshooting from Seven Years of AMSU-B Measurements  

Science Conference Proceedings (OSTI)

This study surveys interannual to diurnal variations of tropical deep convective clouds and convective overshooting using the Advanced Microwave Sounding Unit B (AMSU-B) aboard the NOAA polar orbiting satellites from 1999 to 2005. The methodology ...

Gang Hong; Georg Heygster; Justus Notholt; Stefan A. Buehler

2008-09-01T23:59:59.000Z

435

The Convective Instability Pathway to Warm Season Drought in Texas. Part I: The Role of Convective Inhibition and Its Modulation by Soil Moisture  

Science Conference Proceedings (OSTI)

This research is designed to investigate how convective instability influences monthly mean precipitation in Texas in the summertime and to examine the modulation of convective instability and precipitation by local and regional forcings. Since ...

Boksoon Myoung; John W. Nielsen-Gammon

2010-09-01T23:59:59.000Z

436

Comparing the Convective Structure and Microphysics in Two Sahelian Mesoscale Convective Systems: Radar Observations and CRM Simulations  

Science Conference Proceedings (OSTI)

Two mesoscale convective systems (MCSs) observed during the African Monsoon Multidisciplinary Analyses (AMMA) experiment are simulated using the three-dimensional (3D) Goddard Cumulus Ensemble model. This study was undertaken to determine the ...

Nick Guy; Xiping Zeng; Steven A. Rutledge; Wei-Kuo Tao

2013-02-01T23:59:59.000Z

437

Tropical Island Convection in the Absence of Significant Topography. Part I: Life Cycle of Diurnally Forced Convection  

Science Conference Proceedings (OSTI)

Diurnally forced convection was observed over the Tiwi Islands, north of the Australian continent, as part of the Maritime Continent Thunderstorm Experiment. Immature peninsula-scale (5–15 km) sea breezes were observed to initiate moist ...

R. E. Carbone; J. W. Wilson; T. D. Keenan; J. M. Hacker

2000-10-01T23:59:59.000Z

438

A Satellite-Based Convective Cloud Object Tracking and Multipurpose Data Fusion Tool with Application to Developing Convection  

Science Conference Proceedings (OSTI)

Studying deep convective clouds requires the use of available observation platforms with high temporal and spatial resolution, as well as other non–remote sensing meteorological data (i.e., numerical weather prediction model output, conventional ...

Justin M. Sieglaff; Daniel C. Hartung; Wayne F. Feltz; Lee M. Cronce; Valliappa Lakshmanan

2013-03-01T23:59:59.000Z

439

Simulated Convective Lines with Parallel Stratiform Precipitation. Part I: An Archetype for Convection in Along-Line Shear  

Science Conference Proceedings (OSTI)

This article, the first of two describing convective lines with parallel stratiform (PS) precipitation, addresses the basic kinematic and precipitation features of these systems. The PS mode appears to be the preferred organizational structure in ...

Matthew D. Parker

2007-02-01T23:59:59.000Z

440

Process for separating, especially in multiple stages, acid components such as CO/sub 2/, HCN and specifically H/sub 2/S, from gases, especially from coke oven gases, by means of ammonia recirculation scrubbing  

SciTech Connect

A process of separating in multiple stages acid components in coke oven gas such as CO/sub 2/, HCN and particularly H/sub 2/S by ammonia scrubbing wherein the ammonia used in scrubbing is deacidified to remove the acid components and is recirculated to the scrubbing process at least in part as substantially pure liquid ammonia.

Bauer, H.K.; Otte, E.A.W.

1984-10-16T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Realized and Projected Impacts of U.S. Energy Efficiency Standards for Residential and Commercial Appliances  

E-Print Network (OSTI)

kitchen ranges and ovens, direct heating equipment (wall,Heating Equipment, Mobile Home Furnaces, Kitchen Ranges and Ovens,

Meyers, Stephen P.

2008-01-01T23:59:59.000Z

442

Impacts of Imported Liquefied Natural Gas on Residential Appliance Components: Literature Review  

E-Print Network (OSTI)

Heating Equipment, Mobile Home Furnaces, Kitchen Ranges and Ovens,Heating Equipment, Mobile Home Furnaces, Kitchen Ranges and Ovens,

Lekov, Alex

2010-01-01T23:59:59.000Z

443

Projected Regional Impacts of Appliance Efficiency Standards for the U.S. Residential Sector  

E-Print Network (OSTI)

Heating Equipment, Mobile Home Furnaces, Kitchen Ranges and Ovens,heating, dishwasher motor, domes dryer, gas range and gas oven

Koomey, J.G.

2010-01-01T23:59:59.000Z

444

The Intensification of the Low-Level Jet during the Development of Mesoscale Convective Systems on a Mei-Yu Front  

Science Conference Proceedings (OSTI)

During the period of 21–25 June 1991, a mei-yu front, observed by the post–Taiwan Area Mesoscale Experiment, produced heavy precipitation along the western side of the Central Mountain Range of Taiwan. Several oceanic mesoscale convective systems ...

Chaing Chen; Wei-Kuo Tao; Pay-Liam Lin; George S. Lai; S-F. Tseng; Tai-Chi Chen Wang

1998-02-01T23:59:59.000Z

445

Physics of greenhouse effect and convection in warm Oceans  

SciTech Connect

Sea surface temperatures (SST) in roughly 50% of the tropical Pacific Ocean is warm enough (SST > 300 K) to permit deep convection. This paper examines the effects of deep convection on the climatological mean vertical distributions of water vapor and its greenhouse effect over such warm oceans. The study also examines the link between SST, vertical distribution of water vapor, and its greenhouse effect in the tropical oceans. The radiation model calculations do not include the effects of clouds. The data are grouped into nonconvective and convective categories using SST as an index for convective activity. On average, convective regions are more humid, trap significantly more longwave radiation, and emit more radiation to the sea surface. The greenhouse effect in regions of convection operates as per classical ideas, that is, as the SST increases, the atmosphere traps the excess longwave energy emitted by the surface and reradiates it locally back to the ocean surface. The important departure from the classical picture is that the net (up minus down) fluxes at the surface and at the top-of-the atmosphere decrease with an increase in SST; that is, the surface and the surface-troposphere column lose the ability to radiate the excess energy to space. The cause of this upper greenhouse effect at the surface is the rapid increase in the lower-troposphere humidity with SST; that of the column is due to a combination of increase in humidity in the entire column and increase in the lapse rate within the lower troposphere. The increase in the vertical distribution of humidity far exceeds that which can be attributed to the temperature dependence of saturation vapor pressure; that is, the tropospheric relative humidity is larger in convective regions. The positive coupling between SST and the radiative warming of the surface by the water vapor greenhouse effect is also shown to exist on interannual time scales. 35 refs., 17 figs. 4 tabs.

Inamdar, A.K.; Ramanathan, V. (Univ. of California, San Diego, La Jolla, CA (United States))

1994-05-01T23:59:59.000Z

446

Transient natural convection in heated inclined tubes  

SciTech Connect

To simulate natural convection flow patterns in directionally drilled wellbores, experiments and analyses were conducted for a circular tube with length-to-diameter (L/D) ratio of 36 at angles of 0{degree}, 20{degree}, and 35{degree} from the vertical. The tube was heated at the bottom and cooled at the top, and the insulation was adjusted so that approximately one- to two-thirds of the power dissipated was transferred through the tube wall to the surroundings. An aqueous solution of polyvinyl alcohol was employed as the working fluid in order to obtain low Rayleigh numbers corresponding to conditions in geothermal wellbores. Results were primarily qualitative but were useful in providing insight into the phenomena occurring. Steady-state temperature distributions were measured for the three orientations and for several heating rates to demonstrate the effects of tube angle and Rayleigh number. transient measurements of the temperature distribution were obtained during cooling from a higher temperature without a heat source to calibrate the heat losses. With the electrical heat source, temporal data were taken during heating to examine the approach to steady state. Quasi-steady flow conditions were approached rapidly, but the overall time constant of the apparatus was of the order of one-third of a day. Predictions with the three-dimensional TEMPEST code were first tested by comparison with simple conduction analyses. Comparison with actual data showed good agreement of the predicted temperature levels for the maximum inclination, 35{degree}, and slightly poorer agreement for the other limit, a vertical tube. Trends of temperature level and Nusselt number with heating rate or Rayleigh number were reasonable, but the predicted variation of the end Nusselt number versus inclination was in the opposite direction from the experiment. 75 refs., 20 figs., 8 tabs.

McEligot, D.M. (Westinghouse Electric Corp., Middletown, RI (USA). Oceanic Div.); Denbow, D.A. (Software AG of North America, Inc., Lakewood, CO (USA)); Murphy, H.D. (Los Alamos National Lab., NM (USA))

1990-05-01T23:59:59.000Z

447

Effects of cumulus convection on the simulated monsoon circulation in a general circulation model  

SciTech Connect

The effect of cumulus convection on the Asian summer monsoon circulation is investigated, using a general circulation model. Two simulations for the summer months (June, July, and August) are performed, one parameterizing convection using a mass flux scheme and the other without convective parameterization. The results show that convection has significant effects on the monsoon circulation and its associated precipitation. In the simulation with the mass flux convective parameterization, precipitation in the western Pacific is decreased, together with a decrease in surface evaporation and wind speed. In the indian monsoon region it is almost the opposite. Comparison with a simulation using moist convective adjustment to parameterize convection shows that the monsoon circulation and precipitation distribution in the no-convection simulation are very similar to those in the simulation with moist convective adjustment. The difference in the large-scale circulation with and without convective parameterization is interpreted in terms of convective stabilization of the atmosphere by convection, using dry and moist static energy budgets. It is shown that weakening of the low-level convergence in the western Pacific in the simulation with convection is closely associated with the stabilization of the atmosphere by convection, mostly through drying of the lower troposphere; changes in low-level convergence lead to changes in precipitation. The precipitation increase in the Indian monsoon can be explained similarly. 29 refs., 12 figs.

Zhang, Guang Jun (Univ. of California, San Diego, La Jolla, CA (United States))

1994-09-01T23:59:59.000Z

448

The Dependence of Storm Longevity on the Pattern of Deep Convection Initiation in a Low-Shear Environment  

Science Conference Proceedings (OSTI)

The sensitivity of storm longevity to the pattern of deep convection initiation (e.g., multiple, quasi-linearly arranged initial deep convective cells versus an isolated deep convective cell) is examined using idealized cloud-resolving simulations ...

Adam L. Houston; Robert B. Wilhelmson

2011-10-01T23:59:59.000Z

449

Momentum Flux Spectrum of Convective Gravity Waves. Part I: An Update of a Parameterization Using Mesoscale Simulations  

Science Conference Proceedings (OSTI)

The convective source and momentum flux spectra of a parameterization of convective gravity wave drag (GWDC) are validated in a three-dimensional spectral space using mesoscale numerical simulations for various ideal and real convective storms. ...

Hyun-Joo Choi; Hye-Yeong Chun

2011-04-01T23:59:59.000Z

450

Title: Radar-observed convective characteristics during TWP-ICE  

NLE Websites -- All DOE Office Websites (Extended Search)

Title: Radar-observed convective characteristics during TWP-ICE Title: Radar-observed convective characteristics during TWP-ICE Schumacher, Courtney Texas A&M University Houze, Robert University of Washington May, Peter Bureau or Meteorology Research Centre Frederick, Kaycee Cetrone, Jasmine Vallgren, Andreas Category: Field Campaigns This poster will describe the radar dataset obtained in the Tropical Warm Pool International Cloud Experiment (TWP-ICE), which is to take place 20 January - 14 February 2006 in the vicinity of Darwin, Australia. We will describe the convective systems observed during the project by two scanning C-band Doppler radars, one of which will provide dual-polarization measurements, and ARM's vertically pointing cloud radar and lidar installations. In addition, we will discuss the potential for combining

451

Natural Convection Shutdown Heat Removal Test Facility (NSTF)  

NLE Websites -- All DOE Office Websites (Extended Search)

Natural Convection Natural Convection Shutdown Heat Removal Test Facility Scaling Basis Full Scale Half Scale NSTF Argonne National Laboratory's Natural Convection Shutdown Heat Removal Test Facility (NSTF) - one of the world's largest facilities for ex-vessel passive decay heat removal testing-confirms the performance of reactor cavity cooling systems (RCCS) and similar passive confinement or containment decay heat removal systems in modern Small Modular Reactors. Originally built to aid in the development of General Electric's Power Reactor Innovative Small Module (PRISM) Reactor Vessel Auxiliary Cooling System (RVACS), the NSTF has a long history of providing confirmatory data for the airside of the RVACS. Argonne National Laboratory's NSTF is a state-of-the-art, large-scale facility for evaluating performance

452

ARM - Midlatitude Continental Convective Clouds (comstock-hvps)  

DOE Data Explorer (OSTI)

Convective processes play a critical role in the Earth's energy balance through the redistribution of heat and moisture in the atmosphere and their link to the hydrological cycle. Accurate representation of convective processes in numerical models is vital towards improving current and future simulations of Earths climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales important to convective processes and therefore must turn to parameterization schemes to represent these processes. In turn, parameterization schemes in cloud-resolving models need to be evaluated for their generality and application to a variety of atmospheric conditions. Data from field campaigns with appropriate forcing descriptors have been traditionally used by modelers for evaluating and improving parameterization schemes.

Mike Jensen; Jennifer Comstock; Anthony Del Genio; Scott Giangrande; Pavlos Kollias

453

ARM - Midlatitude Continental Convective Clouds (comstock-hvps)  

Science Conference Proceedings (OSTI)

Convective processes play a critical role in the Earth's energy balance through the redistribution of heat and moisture in the atmosphere and their link to the hydrological cycle. Accurate representation of convective processes in numerical models is vital towards improving current and future simulations of Earths climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales important to convective processes and therefore must turn to parameterization schemes to represent these processes. In turn, parameterization schemes in cloud-resolving models need to be evaluated for their generality and application to a variety of atmospheric conditions. Data from field campaigns with appropriate forcing descriptors have been traditionally used by modelers for evaluating and improving parameterization schemes.

Mike Jensen; Jennifer Comstock; Anthony Del Genio; Scott Giangrande; Pavlos Kollias

2012-01-06T23:59:59.000Z

454

Aspects of forced convective heat transfer in geothermal systems  

DOE Green Energy (OSTI)

A knowledge of convective heat transfer is essential to understanding geothermal systems and other systems of moving groundwater. A simple, kinematic approach toward convective heat transfer is taken here. Concern is not with the cause of the groundwater motion but only with the fact that the water is moving and transferring heat. The mathematical basis of convective heat transfer is the energy equation which is a statement of the first law of thermodynamics. The general solution of this equation for a specific model of groundwater flow has to be done numerically. The numerical algorithm used here employs a finite difference approximation to the energy equation that uses central differences for the heat conduction terms and one-sided differences for the heat convection terms. Gauss--Seidel iteration is then used to solve the finite difference equation at each node of a non-uniform mesh. The Monroe and Red Hill hot springs, a small hydrothermal system in central Utah, provide an example to illustrate the application of convective heat transfer theory to a geophysical problem. Two important conclusions regarding small geothermal systems follow immediately from the results of this application. First, the most rapid temperature rise in the convecting part of a geothermal system is near the surface. Below this initially rapid temperature increase the temperature increases very slowly, and thus temperatures extrapolated from shallow boreholes can be seriously in error. Second, the temperatures and heat flows observed at Monroe and Red Hill, and probably at many other small geothermal areas, can easily result from moderate vertical groundwater velocities in faults and fracture zones in an area of normal heat flow.

Kilty, K.; Chapman, D.S.; Mase, C.

1978-07-01T23:59:59.000Z

455

High order ZIP' differencing of convective terms. Memorandum report  

Science Conference Proceedings (OSTI)

The ZIP flux form for differencing the term (wv) sub x, where w is a convected quantity and v is a convective velocity, is observed to be equivalent to differencing the alternative expression wv sub x + w sub x v using centered second order finite differences. Based on this observation, the extension of the ZIP flux concept to arbitrarily high order accuracy is given. Computational examples show the advantage both of the ZIP flux concept itself and of its higher order forms within the context of flux-corrected transport (FCT) algorithms.

Zalesak, S.T.

1980-05-08T23:59:59.000Z

456

Midlatitude Continental Convective Clouds Experiment (MC3E)  

SciTech Connect

Convective processes play a critical role in the Earth’s energy balance through the redistribution of heat and moisture in the atmosphere and subsequent impacts on the hydrologic cycle. Global observation and accurate representation of these processes in numerical models is vital to improving our current understanding and future simulations of Earth’s climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales that are associated with convective and stratiform precipitation processes; therefore, they must turn to parameterization schemes to represent these processes. In turn, the physical basis for these parameterization schemes needs to be evaluated for general application under a variety of atmospheric conditions. Analogously, space-based remote sensing algorithms designed to retrieve related cloud and precipitation information for use in hydrological, climate, and numerical weather prediction applications often rely on physical “parameterizations” that reliably translate indirectly related instrument measurements to the physical quantity of interest (e.g., precipitation rate). Importantly, both spaceborne retrieval algorithms and model convective parameterization schemes traditionally rely on field campaign data sets as a basis for evaluating and improving the physics of their respective approaches. The Midlatitude Continental Convective Clouds Experiment (MC3E) will take place in central Oklahoma during the April–May 2011 period. The experiment is a collaborative effort between the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility and the National Aeronautics and Space Administration’s (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The field campaign leverages the unprecedented observing infrastructure currently available in the central United States, combined with an extensive sounding array, remote sensing and in situ aircraft observations, NASA GPM ground validation remote sensors, and new ARM instrumentation purchased with American Recovery and Reinvestment Act funding. The overarching goal is to provide the most complete characterization of convective cloud systems, precipitation, and the environment that has ever been obtained, providing constraints for model cumulus parameterizations and space-based rainfall retrieval algorithms over land that have never before been available. Several different components of convective cloud and precipitation processes tangible to both the convective parameterization and precipitation retrieval algorithm problem are targeted, such as preconvective environment and convective initiation, updraft/downdraft dynamics, condensate transport and detrainment, precipitation and cloud microphysics, spatial and temporal variability of precipitation, influence on the environment and radiation, and a detailed description of the large-scale forcing.

Jensen, MP; Petersen, WA; Del Genio, AD; Giangrande, SE; Heymsfield, A; Heymsfield, G; Hou, AY; Kollias, P; Orr, B; Rutledge, SA; Schwaller, MR; Zipser, E

2010-04-01T23:59:59.000Z

457

Predictions of convective losses from a solar cavity receiver  

SciTech Connect

Convective losses arising from buoyancy driven flow were calculated for a two-dimensional model simulating a solar cavity receiver. The TEMPEST code, capable of fully three-dimensional coupled thermal-hydraulic transient calculations, was used for the simulation. Predicted velocity and temperature results for a 2.59 m deep by 2.88 m high rectangular cavity with an aperture opening of 1.72 m were used to determine convective losses for prescribed interior wall temperatures and cavity orientation. Velocity vector and temperature isotherm plots were used to analyze flow characteristics.

Eyler, L.L.

1979-12-01T23:59:59.000Z

458

An Idealized Cloud-Resolving Framework for the Study of Midlatitude Diurnal Convection over Land  

Science Conference Proceedings (OSTI)

This paper introduces an idealized cloud-resolving modeling (CRM) framework for the study of midlatitude diurnal convection over land. The framework is used to study the feedbacks among soil, boundary layer, and diurnal convection. It includes a ...

Linda Schlemmer; Cathy Hohenegger; Jürg Schmidli; Christopher S. Bretherton; Christoph Schär

2011-05-01T23:59:59.000Z

459

A Systemic Analysis of Multiscale Deep Convective Variability over the Tropical Pacific  

Science Conference Proceedings (OSTI)

The multiscale tropical deep convective variability over the Pacific Ocean is examined with the 4-month high-resolution deep convection index (ITBB) derived from satellite imagery. With a systemic view, the complex phenomenon is described with ...

Wen-wen Tung; Mitchell W. Moncrieff; Jian-Bo Gao

2004-07-01T23:59:59.000Z

460

Radar Analysis of a Tropical Convective Boundary Layer with Shallow Cumulus Clouds  

Science Conference Proceedings (OSTI)

A situation of fair weather cloudy convection is examined using a dual Doppler radar, environmental measurements and cloud photogrammetry. The convective layer is characterized by the interaction between the northward monsoon wind at low levels ...

Laurence Eymard

1984-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Convectively Generated Gravity Waves and Their Effect on the Cloud Environment  

Science Conference Proceedings (OSTI)

This study uses a two-dimensional cloud-resolving model to examine how convectively generated gravity waves modify the environment of an isolated convective cloud. The model is initialized with an idealized sounding, and the cloud is initiated by ...

Todd P. Lane; Michael J. Reeder

2001-08-01T23:59:59.000Z

462

A Satellite Infrared Technique to Estimate Tropical Convective and Stratiform Rainfall  

Science Conference Proceedings (OSTI)

This paper describes a new method of estimating both tropical convective precipitation and stratiform precipitation (produced under the anvils of mature and decaying convective systems) from satellite infrared data. The method, denoted CST (...

Robert F. Adler; Andrew J. Negri

1988-01-01T23:59:59.000Z

463

A Mass Flux Convection Scheme with Representation of Cloud Ensemble Characteristics and Stability-Dependent Closure  

Science Conference Proceedings (OSTI)

The convection scheme used at the UK Meteorological Office in large-scale numerical models is described. The scheme uses a “bulk” cloud model to represent an ensemble of convective clouds and aims to represent shallow, deep and midlevel ...

D. Gregory; P. R. Rowntree

1990-07-01T23:59:59.000Z

464

Numerical Simulation of Transitions in Boundary Layer Convective Structures in a Lake-Effect Snow Event  

Science Conference Proceedings (OSTI)

Numerical simulations are used to study transitions between boundary layer rolls and more cellular convective structures observed during a lake-effect snow event over Lake Michigan on 17 December 1983. Weak lake-effect nonroll convection was ...

Kevin A. Cooper; Mark R. Hjelmfelt; Russell G. Derickson; David A. R. Kristovich; Neil F. Laird

2000-09-01T23:59:59.000Z

465

Atmospheric Circulation Anomalies during Episodes of Enhanced and Reduced Convective Cloudiness over Uruguay  

Science Conference Proceedings (OSTI)

Regional and large-scale circulation anomalies associated with periods of enhanced and reduced convective cloudiness over Uruguay are studied for austral spring and summer, when rainfall associated with deep convection is more frequent in this ...

Alvaro DÍaz; Patricio Aceituno

2003-10-01T23:59:59.000Z

466

Deep convection triggering by boundary layer thermals. Part 1: LES analysis and stochastic triggering formulation  

Science Conference Proceedings (OSTI)

This paper proposes a new formulation of the deep convection triggering for GCM (General Circulation Model) convective parameterizations. This triggering is driven by evolving properties of the strongest boundary-layer thermals. To investigate ...

Nicolas Rochetin; Fleur Couvreux; Jean-Yves Grandpeix; Catherine Rio

467

Mesoscale Impacts of Explicit Numerical Diffusion in a Convection-Permitting Model  

Science Conference Proceedings (OSTI)

In convection-permitting simulations, the spectrum of resolved motions is truncated near scales where convection is active. An “energy gap” between resolved and unresolved motions does not exist, such that the upscale and downscale fluxes of ...

Wolfgang Langhans; Juerg Schmidli; Christoph Schär

2012-01-01T23:59:59.000Z

468

Surface-Flux Regulation of the Coupling between Cumulus Convection and Baroclinic Waves  

Science Conference Proceedings (OSTI)

The authors examine the role of convection in the dynamics of eddy life cycles through numerical experiments using initial states that are baroclinically and conditionally unstable in midlatitudes. The location of wave-induced convection and its ...

William J. Gutowski Jr.; Weidong Jiang

1998-03-01T23:59:59.000Z

469

Generation and Trapping of Gravity Waves from Convection with Comparison to Parameterization  

Science Conference Proceedings (OSTI)

Some parameterizations of gravity wave mean flow forcing in global circulation models (GCMs) add realism by describing wave generation by tropospheric convection. Because the convection in GCMs is itself a parameterized process, these ...

M. Joan Alexander; Jadwiga H(Beres) Richter; Bruce R. Sutherland

2006-11-01T23:59:59.000Z

470

Stochastic behavior of tropical convection in observations and a multicloud model  

Science Conference Proceedings (OSTI)

The aim for a more accurate representation of tropical convection in global circulation models is a long-standing issue. Here, the relationships between large- and convective scales in observations and a Stochastic Multicloud Model (SMCM) to ...

Karsten Peters; Christian Jakob; Laura Davies; Boualem Khouider; Andrew J. Majda

471

Walker-Type Mean Circulations and Convectively Coupled Tropical Waves as an Interacting System  

Science Conference Proceedings (OSTI)

Interactions between convectively coupled tropical waves and Walker-type mean circulations are examined using a two-dimensional analytic model wherein drying and cooling of the boundary layer by convective and mesoscale downdrafts are in ...

Jun-Ichi Yano; Mitchell W. Moncrieff; Wojciech W. Grabowski

2002-05-01T23:59:59.000Z

472

Airflow and Precipitation Structure of Two Leading Stratiform Mesoscale Convective Systems Determined from Operational Datasets  

Science Conference Proceedings (OSTI)

An analysis of the airflow and precipitation structure of two leading stratiform (LS) mesoscale convective systems (MCSs) is presented. Leading stratiform systems are defined as linear MCSs that consist of a convective line with leading ...

Crystalyne R. Pettet; Richard H. Johnson

2003-10-01T23:59:59.000Z

473

The 30–60-Day Convection Seesaw between the Tropical Indian and Western Pacific Oceans  

Science Conference Proceedings (OSTI)

The tropical Indian and western Pacific oceans are two prominent action centers for tropical 30–60-day convective variability. When convection is enhanced over the equatorial Indian Ocean, the tropical western Pacific often experiences an ...

Baozhen Zhu; Bin Wang

1993-01-01T23:59:59.000Z

474

Environment and the Lifetime of Tropical Deep Convection in a Cloud-Permitting Regional Model Simulation  

Science Conference Proceedings (OSTI)

By applying a cloud tracking algorithm to tropical convective systems in a simulated a regional high resolution model simulation, this study documents the environmental conditions before and after convective systems are initiated over ocean and ...

Samson Hagos; Zhe Feng; Sally McFarlane; L. Ruby Leung

475

Convective Structures in a Cold Air Outbreak over Lake Michigan during Lake-ICE  

Science Conference Proceedings (OSTI)

The Lake-Induced Convection Experiment provided special field data during a westerly flow cold air outbreak (CAO) on 13 January 1998, which has afforded the opportunity to examine in detail an evolving convective boundary layer. Vertical cross ...

Suzanne M. Zurn-Birkhimer; Ernest M. Agee; Zbigniew Sorbjan

2005-07-01T23:59:59.000Z

476

The Vertical Structure of TOGA COARE Convection. Part II: Modulating Influences and Implications for Diabatic Heating  

Science Conference Proceedings (OSTI)

The temporal variability of western Pacific warm pool convection, especially its vertical structure, is examined in this study. Distributions of convective echo top heights and 30-dBZ contour heights have been produced from shipboard radar data ...

Charlotte A. DeMott; Steven A. Rutledge

1998-09-01T23:59:59.000Z

477

From Hot Towers to TRMM: Joanne Simpson and Advances in Tropical Convection Research  

Science Conference Proceedings (OSTI)

Joanne Simpson began contributing to advances in tropical convection about half a century ago. The hot tower hypothesis jointly put forth by Joanne Simpson and Herbert Riehl postulated that deep convective clouds populating the “equatorial trough ...

Robert A. Houze Jr.

2003-01-01T23:59:59.000Z

478

Updraft and Downdraft Statistics of Simulated Tropical and Midlatitude Cumulus Convection  

Science Conference Proceedings (OSTI)

This paper presents a detailed analysis of updraft and downdraft statistics of simulated tropical oceanic and midlatitude continental cumulus convection, with an emphasis on the individual terms in the vertical momentum budget. Strong convective ...

Kuan-Man Xu; David A. Randall

2001-07-01T23:59:59.000Z

479

An Intraseasonal Oscillation Composite Life Cycle in the NCAR CCM3.6 with Modified Convection  

Science Conference Proceedings (OSTI)

The NCAR CCM3.6 with microphysics of clouds with relaxed Arakawa–Schubert convection produces an intraseasonal oscillation that is highly dependent on lower-tropospheric moistening by surface convergence. Model intraseasonal convection is most ...

Eric D. Maloney

2002-05-01T23:59:59.000Z

480

A Model of Rossby Waves Linked to Submonthly Convection over the Eastern Tropical Pacific  

Science Conference Proceedings (OSTI)

Equatorward-propagating wave trains in the upper troposphere are observed to be associated with deep convection over the eastern tropical Pacific on the submonthly timescale during northern winter. The convection occurs in the regions of ascent ...

Adrian J. Matthews; George N. Kiladis

2000-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "range convection oven" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Observations of Convection Initiation “Failure” from the 12 June 2002 IHOP Deployment  

Science Conference Proceedings (OSTI)

Observations of the development of cumulus convection, which reached depths of several kilometers but failed to develop into sustained, precipitating, cumulonimbus clouds—an event the authors term “convection initiation failure”—are presented ...

Paul Markowski; Christina Hannon; Erik Rasmussen

2006-01-01T23:59:59.000Z

482

Horizontal Convective Rolls: Determining the Environmental Conditions Supporting their Existence and Characteristics  

Science Conference Proceedings (OSTI)

Data from the Convection and Precipitation/Electrification (CaPE) project, as well as results from numerical simulations, are used to study horizontal convective rolls. The environmental conditions necessary for sustaining rolls and for ...

Tammy M. Weckwerth; James W. Wilson; Roger M. Wakimoto; N. Andrew Crook

1997-04-01T23:59:59.000Z

483

A Cumulus Parameterization Based on the Generalized Convective Available Potential Energy  

Science Conference Proceedings (OSTI)

This paper reports tests of a cumulus parameterization in which the reference state associated with the generalized convective available potential energy (GCAPE) is chosen as the end-state of the convective adjustment. The GCAPE is defined as the ...

Junyi Wang; David A. Randall

1996-03-01T23:59:59.000Z

484

Exploring the Land–Ocean Contrast in Convective Vigor Using Islands  

Science Conference Proceedings (OSTI)

Moist convection is well known to be generally more intense over continental than maritime regions, with larger updraft velocities, graupel, and lightning production. This study explores the transition from maritime to continental convection by ...

F. J. Robinson; S. C. Sherwood; D. Gerstle; C. Liu; D. J. Kirshbaum

2011-03-01T23:59:59.000Z

485

The Cooperative Convective Precipitation Experiment (CCOPE), 18 May-7 August 1981  

Science Conference Proceedings (OSTI)

The Cooperative Convective Precipitation Experiment, CCOPE, was an outgrowth of the perceived need for more comprehensive data sets on convective clouds. It was planned and executed by a large group of participants, with the leadership of the ...

Charles A. Knight

1982-04-01T23:59:59.000Z

486

The Relationship between Tropical Cyclone Intensity Change and the Strength of Inner-Core Convection  

Science Conference Proceedings (OSTI)

Convective intensity proxies measured by the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), Precipitation Radar (PR), and Visible and Infrared Scanner (VIRS) are used to assess the relationship between intense convection in the ...

Haiyan Jiang

2012-04-01T23:59:59.000Z

487

Observational Evaluation of a Convective Quasi-Equilibrium View of Monsoons  

Science Conference Proceedings (OSTI)

Idealized dynamical theories that employ a convective quasi-equilibrium (QE) treatment for the diabatic effects of moist convection have been used to explain the location, intensity, and intraseasonal evolution of monsoons. This paper examines ...

Ji Nie; William R. Boos; Zhiming Kuang

2010-08-01T23:59:59.000Z

488

Representing equilibrium and non-equilibrium convection in large-scale models  

Science Conference Proceedings (OSTI)

A new diagnostic convective closure, which is dependent on the convective available potential energy (CAPE), is derived under the quasi-equilibrium assumption for the free troposphere subject to boundary-layer forcing. The closure involves a ...

Peter Bechtold; Noureddine Semane; Philippe Lopez; Jean-Pierre Chaboureau; Anton Beljaars; Niels Bormann

489

A Fractal Interfacial Entrainment Model for Dry Convective Boundary Layers. Part I: Model Description  

Science Conference Proceedings (OSTI)

An entrainment model for the convective planetary boundary layer is presented. It is based upon an ensemble-averaged view of the local entrainment interface that caps the convective mixed layer. Fractal and variational methods are used to ...

Ray F. Kamada

1988-09-01T23:59:59.000Z

490

Development of a Probabilistic Convective Weather Forecast Threshold Parameter for Flight-Routing Decisions  

Science Conference Proceedings (OSTI)

This paper presents a method for determining a threshold value of probabilistic convective weather forecast data. By synchronizing air traffic data and an experimental probabilistic convective weather forecast product, it was observed that ...

Kapil Sheth; Thomas Amis; Sebastian Gutierrez-Nolasco; Banavar Sridhar; Daniel Mulfinger

2013-10-01T23:59:59.000Z

491

Convective Forcing Fluctuations in a Cloud-Resolving Model: Relevance to the Stochastic Parameterization Problem  

Science Conference Proceedings (OSTI)

Idealized cloud-resolving model (CRM) simulations spanning a large part of the tropical atmosphere are used to evaluate the extent to which deterministic convective parameterizations fail to capture the statistical fluctuations in deep-convective ...

G. J. Shutts; T. N. Palmer

2007-01-01T23:59:59.000Z

492

Numerical Study of Penetrative and “Solid Lid” Nonpenetrative Convective Boundary Layers  

Science Conference Proceedings (OSTI)

A large eddy simulation model was used to generate and compare statistics of turbulence during nonpenetrative and penetrative dry convection. In penetrative convection dimensionless vertical velocities in updrafts were found to have almost the ...

Zbigniew Sorbjan

1996-01-01T23:59:59.000Z

493

An Analysis of the Environments of Intense Convective Systems in West Africa in 2003  

Science Conference Proceedings (OSTI)

The local- and regional-scale environments associated with intense convective systems in West Africa during 2003 were diagnosed from soundings, operational analysis, and space-based datasets. Convective system cases were identified from the ...

Stephen D. Nicholls; Karen I. Mohr

2010-10-01T23:59:59.000Z

494

Kinematic Vertical Motion and Relative Vorticity Profiles in a Long-Lived Midlatitude Convective System  

Science Conference Proceedings (OSTI)

Average kinematic vertical motion and relative vorticity profiles are presented for a long-lived midlatitude convective complex. A breakdown into active convective and stratiform precipitation regions shows very good agreement in the vertical ...

Lance F. Bosart

1986-06-01T23:59:59.000Z

495

Influence of Balanced Motions on Heavy Precipitation within a Long-Lived Convectively Generated Vortex  

Science Conference Proceedings (OSTI)

The forcing of heavy precipitation within a long-lived convectively generated mesoscale vortex (MCV) is investigated with the aid of diagnoses from Rapid Update Cycle gridded analyses. Organized convection within the MCV followed a distinct ...

Stanley B. Trier; Christopher A. Davis

2002-04-01T23:59:59.000Z

496

Model Study of Waves Generated by Convection with Direct Validation via Satellite  

Science Conference Proceedings (OSTI)

Atmospheric gravity waves have a major effect on atmospheric circulation, structure, and stability on a global scale. Gravity waves can be generated by convection, but in many cases it is difficult to link convection directly to a specific wave ...

Alison W. Grimsdell; M. Joan Alexander; Peter T. May; Lars Hoffmann

2010-05-01T23:59:59.000Z

497

Improved Madden–Julian Oscillations with Improved Physics: The Impact of Modified Convection Parameterizations  

Science Conference Proceedings (OSTI)

Two modifications are made to the deep convection parameterization in the NCAR Community Climate System Model, version 3 (CCSM3): a dilute plume approximation and an implementation of the convective momentum transport (CMT). These changes lead to ...

Lei Zhou; Richard B. Neale; Markus Jochum; Raghu Murtugudde

2012-02-01T23:59:59.000Z

498

Forecasting Convective Initiation by Monitoring the Evolution of Moving Cumulus in Daytime GOES Imagery  

Science Conference Proceedings (OSTI)

This study identifies the precursor signals of convective initiation within sequences of 1-km-resolution visible (VIS) and 4–8-km infrared (IR) imagery from the Geostationary Operational Environmental Satellite (GOES) instrument. Convective ...

John R. Mecikalski; Kristopher M. Bedka

2006-01-01T23:59:59.000Z

499

Development and Evaluation of a Convection Scheme for Use in Climate Models  

Science Conference Proceedings (OSTI)

Cumulus convection is a key process in controlling the water vapor content of the atmosphere, which is in turn the largest feedback mechanism for climate change in global climate models. Yet scant attention has been paid to designing convective ...

Kerry A. Emanuel; Marina Živkovi?-Rothman

1999-06-01T23:59:59.000Z

500

Intense Convection Observed by NASA ER-2 in Hurricane Emily (2005)  

Science Conference Proceedings (OSTI)

On 17 July, intense convection in the eyewall of Hurricane Emily (2005) was observed by the high-altitude (20 km) NASA ER-2 aircraft. Analysis of this convection is undertaken using downward-looking radar, passive microwave radiometer, electric ...

Daniel J. Cecil; Kevin R. Quinlan; Douglas M. Mach

2010-03-01T23:59:59.000Z