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1

Modeling-Computer Simulations (Walker, Et Al., 2005) | Open Energy...  

Open Energy Info (EERE)

Modeling-Computer Simulations (Walker, Et Al., 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations (Walker, Et...

2

Modeling-Computer Simulations | Open Energy Information  

Open Energy Info (EERE)

Modeling-Computer Simulations Modeling-Computer Simulations Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Modeling-Computer Simulations Details Activities (78) Areas (31) Regions (5) NEPA(0) Exploration Technique Information Exploration Group: Data and Modeling Techniques Exploration Sub Group: Modeling Techniques Parent Exploration Technique: Modeling Techniques Information Provided by Technique Lithology: Stratigraphic/Structural: Stress fields and magnitudes Hydrological: Visualization and prediction of the flow patterns and characteristics of geothermal fluids Thermal: Thermal conduction and convection patterns in the subsurface Cost Information Low-End Estimate (USD): 85.008,500 centUSD 0.085 kUSD 8.5e-5 MUSD 8.5e-8 TUSD / hour Median Estimate (USD): 195.0019,500 centUSD

3

Modeling-Computer Simulations (Lewicki & Oldenburg, 2004) | Open Energy  

Open Energy Info (EERE)

Modeling-Computer Simulations (Lewicki & Oldenburg, Modeling-Computer Simulations (Lewicki & Oldenburg, 2004) Exploration Activity Details Location Unspecified Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes In this section we present numerical simulations of CO2 migration, seepage, and atmospheric dispersion. The purpose of these simulations is to evaluate the magnitudes and form of anomalous CO2 concentrations and fluxes that might be expected to emanate from a given model hidden geothermal system. From this information, we can design and evaluate potential monitoring and detection methods. References Jennifer L. Lewicki, Curtis M. Oldenburg (2004) Strategies For Detecting Hidden Geothermal Systems By Near-Surface Gas Monitoring Retrieved from

4

Modeling-Computer Simulations At White Mountains Area (Goff ...  

Open Energy Info (EERE)

Modeling-Computer Simulations At White Mountains Area (Goff & Decker, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer...

5

Modeling-Computer Simulations At Nw Basin & Range Region (Biasi...  

Open Energy Info (EERE)

Modeling-Computer Simulations At Nw Basin & Range Region (Biasi, Et Al., 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer...

6

Modeling-Computer Simulations At Central Nevada Seismic Zone...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Central Nevada Seismic Zone Region (Pritchett, 2004) Exploration...

7

Modeling-Computer Simulations At Dixie Valley Geothermal Field...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Dixie Valley Geothermal Field Area (Wisian & Blackwell, 2004)...

8

Modeling-Computer Simulations At Desert Peak Area (Wisian & Blackwell...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Desert Peak Area (Wisian & Blackwell, 2004) Exploration Activity...

9

Modeling-Computer Simulations At Nevada Test And Training Range...  

Open Energy Info (EERE)

Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At Nevada Test And Training Range Area (Sabin, Et Al., 2004) Jump to: navigation, search GEOTHERMAL...

10

Modeling-Computer Simulations At Central Nevada Seismic Zone...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Central Nevada Seismic Zone Region (Biasi, Et Al., 2009) Exploration...

11

Modeling-Computer Simulations At Walker-Lane Transitional Zone...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Walker-Lane Transitional Zone Region (Biasi, Et Al., 2009) Exploration...

12

Modeling-Computer Simulations At Northern Basin & Range Region...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Northern Basin & Range Region (Blackwell, Et Al., 2003) Exploration...

13

Modeling-Computer Simulations At Nw Basin & Range Region (Pritchett...  

Open Energy Info (EERE)

Login | Sign Up Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At Nw Basin & Range Region (Pritchett, 2004) Jump to: navigation, search...

14

Modeling-Computer Simulations At Walker-Lane Transitional Zone...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Walker-Lane Transitional Zone Region (Pritchett, 2004) Exploration...

15

Modeling-Computer Simulations At Valles Caldera - Sulphur Springs...  

Open Energy Info (EERE)

Modeling-Computer Simulations At Valles Caldera - Sulphur Springs Area (Wilt & Haar, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

16

Modeling-Computer Simulations At Long Valley Caldera Area (Farrar...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Long Valley Caldera Area (Farrar, Et Al., 2003) Exploration Activity...

17

Modeling-Computer Simulations At San Juan Volcanic Field Area...  

Open Energy Info (EERE)

Login | Sign Up Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At San Juan Volcanic Field Area (Clarkson & Reiter, 1987) Jump to:...

18

Modeling-Computer Simulations At Fish Lake Valley Area (Deymonaz...  

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Login | Sign Up Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At Fish Lake Valley Area (Deymonaz, Et Al., 2008) Jump to: navigation,...

19

Modeling-Computer Simulations At Long Valley Caldera Area (Pribnow...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Long Valley Caldera Area (Pribnow, Et Al., 2003) Exploration Activity...

20

Modeling-Computer Simulations At Fenton Hill Hdr Geothermal Area...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Fenton Hill Hdr Geothermal Area (Goff & Decker, 1983) Exploration...

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Modeling-Computer Simulations At Valles Caldera - Redondo Area...  

Open Energy Info (EERE)

Login | Sign Up Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At Valles Caldera - Redondo Area (Roberts, Et Al., 1995) Jump to:...

22

Modeling-Computer Simulations At Valles Caldera - Sulphur Springs...  

Open Energy Info (EERE)

Modeling-Computer Simulations At Valles Caldera - Sulphur Springs Area (Roberts, Et Al., 1995) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

23

Modeling-Computer Simulations At Chocolate Mountains Area (Alm...  

Open Energy Info (EERE)

Login | Sign Up Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At Chocolate Mountains Area (Alm, Et Al., 2010) Jump to: navigation,...

24

Modeling-Computer Simulations At Long Valley Caldera Area (Newman...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Long Valley Caldera Area (Newman, Et Al., 2006) Exploration Activity...

25

Modeling-Computer Simulations At Fenton Hill Hdr Geothermal Area...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Fenton Hill Hdr Geothermal Area (Heiken & Goff, 1983) Exploration...

26

Modeling-Computer Simulations At Central Nevada Seismic Zone...  

Open Energy Info (EERE)

Modeling-Computer Simulations At Central Nevada Seismic Zone Region (Blackwell, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

27

Modeling-Computer Simulations At Dixie Valley Geothermal Field...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Dixie Valley Geothermal Field Area (Blackwell, Et Al., 2009)...

28

Modeling-Computer Simulations At Stillwater Area (Wisian & Blackwell...  

Open Energy Info (EERE)

Login | Sign Up Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At Stillwater Area (Wisian & Blackwell, 2004) Jump to: navigation, search...

29

Modeling-Computer Simulations At Valles Caldera - Redondo Area...  

Open Energy Info (EERE)

Modeling-Computer Simulations At Valles Caldera - Redondo Area (Wilt & Haar, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

30

Modeling-Computer Simulations At The Needles Area (Bell & Ramelli...  

Open Energy Info (EERE)

Login | Sign Up Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At The Needles Area (Bell & Ramelli, 2009) Jump to: navigation, search...

31

Modeling-Computer Simulations At Dixie Valley Geothermal Field...  

Open Energy Info (EERE)

Modeling-Computer Simulations At Dixie Valley Geothermal Field Area (Kennedy & Van Soest, 2006) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity:...

32

Modeling-Computer Simulations At Kilauea East Rift Area (Rudman...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Kilauea East Rift Area (Rudman & Epp, 1983) Exploration Activity...

33

Modeling-Computer Simulations At Stillwater Area (Wisian & Blackwell, 2004)  

Open Energy Info (EERE)

Stillwater Area (Wisian & Blackwell, 2004) Stillwater Area (Wisian & Blackwell, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Stillwater Area (Wisian & Blackwell, 2004) Exploration Activity Details Location Stillwater Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown References Kenneth W. Wisian, David D. Blackwell (2004) Numerical Modeling Of Basin And Range Geothermal Systems Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Stillwater_Area_(Wisian_%26_Blackwell,_2004)&oldid=387304" Categories: Exploration Activities DOE Funded Activities What links here Related changes Special pages Printable version

34

Modeling-Computer Simulations (Combs, Et Al., 1999) | Open Energy  

Open Energy Info (EERE)

Modeling-Computer Simulations (Combs, Et Al., 1999) Modeling-Computer Simulations (Combs, Et Al., 1999) Exploration Activity Details Location Unspecified Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Various models/simulations used to analyze data obtained from slimhole drilling. References Jim Combs, John T. Finger, Colin Goranson, Charles E. Hockox Jr., Ronald D. Jacobsen, Gene Polik (1999) Slimhole Handbook- Procedures And Recommendations For Slimhole Drilling And Testing In Geothermal Exploration Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_(Combs,_Et_Al.,_1999)&oldid=387232" Category: Exploration Activities What links here Related changes Special pages Printable version Permanent link Browse properties

35

Modeling-Computer Simulations At Raft River Geothermal Area (1983) | Open  

Open Energy Info (EERE)

Modeling-Computer Simulations At Raft River Geothermal Area (1983) Modeling-Computer Simulations At Raft River Geothermal Area (1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Raft River Geothermal Area (1983) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date 1983 Usefulness useful DOE-funding Unknown Exploration Basis Predict flow rate and porosity Notes The objectives of the physical modeling effort are to: (1) evaluate injection-backflow testing for fractured reservoirs under conditions of known reservoir parameters (porosity, fracture width, etc.); (2) study the mechanisms controlling solute transport in fracture systems; and (3) provide data for validation of numerical models that explicitly simulate

36

Modeling-Computer Simulations (Laney, 2005) | Open Energy Information  

Open Energy Info (EERE)

Modeling-Computer Simulations (Laney, 2005) Modeling-Computer Simulations (Laney, 2005) Exploration Activity Details Location Unspecified Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes Design of Sampling Strategies to Detect CO2 Emissions From Hidden Geothermal Systems, Lewicki, Oldenburg and Kennedy. The objective of this project is to investigate geothermal CO2 monitoring in the near surface as a tool to discover hidden geothermal reservoirs. A primary goal of this project is to develop an approach that places emphasis on cost and time-efficient near-surface exploration methods and yields results to guide and focus more cost-intensive geophysical measurements, installation of deep wells, and geochemical analyses of deep fluids. To this end, we

37

Modeling-Computer Simulations (Ozkocak, 1985) | Open Energy Information  

Open Energy Info (EERE)

Ozkocak, 1985) Ozkocak, 1985) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations (Ozkocak, 1985) Exploration Activity Details Location Unspecified Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes CONTRIBUTION OF THE LATEST ADVANCES IN GEOLOGY, GEOCHEMISTRY AND GEOPHYSICS TO GEOTHERMAL PROSPECTING. Twenty-five papers were received on this topic, 14 of them concerning geology, four geochemistry and seven geophysics. The papers dealing with geology describe attempts to build models of underground geothermal activity and study the factors that control the formation of reservoir and cap rocks (regional plate tectonics, local tectonics, stratigraphy, geochemistry and volcanism) and the relations

38

Modeling-Computer Simulations At U.S. West Region (Laney, 2005) | Open  

Open Energy Info (EERE)

Modeling-Computer Simulations At U.S. West Region Modeling-Computer Simulations At U.S. West Region (Laney, 2005) Exploration Activity Details Location U.S. West Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful regional reconnaissance DOE-funding Unknown Notes Characterization and Conceptual Modeling of Magmatically-Heated and Deep-Circulation, High-Temperature Hydrothermal Systems in the Basin and Range and Cordilleran United States, Moore, Nash, Nemcok, Lutz, Norton, Kaspereit, Berard, van de Putte, Johnson and Deymonaz. Utilizing a wealth of formerly proprietary subsurface samples and datasets for exemplary high-temperature western U.S. geothermal systems, develop and publish detailed and refined new conceptual and numerical hydrothermal-history models of fundamental scientific import but, more importantly, of use to

39

Modeling-Computer Simulations At Valles Caldera - Sulphur Springs Area  

Open Energy Info (EERE)

Wilt & Haar, 1986) Wilt & Haar, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Valles Caldera - Sulphur Springs Area (Wilt & Haar, 1986) Exploration Activity Details Location Valles Caldera - Sulphur Springs Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes A computer program capable of two-dimensional modeling of gravity data was used in interpreting gravity observations along profiles A--A' and B--B' (Talwani et al., 1959). Densities of 2.12, 2.40, and 2.65 g/cm a were used for modeling the near-surface caldera fill, the underlying volcanics, and the basement sections, respectively (Fig. 8). Although correlation with well data was done whenever possible, there is some uncertainty to the

40

Modeling-Computer Simulations At Yellowstone Region (Laney, 2005) | Open  

Open Energy Info (EERE)

Laney, 2005) Laney, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Yellowstone Region (Laney, 2005) Exploration Activity Details Location Yellowstone Caldera Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful regional reconnaissance DOE-funding Unknown Notes Localized Strain as a Discriminator of Hidden Geothermal Systems, Vasco and Foxall, 2005. Recent work has focused on (1) collaborating with Alessandro Ferretti to use Permanent Scatterer (PS) InSAR data to infer strain at depth, (2) working with Lane Johnson to develop a dynamic faulting model, and (3) acquiring InSAR data for the region surrounding the Dixie Valley fault zone in collaboration with Dr. William Foxall of LLNL. The InSAR data

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Modeling-Computer Simulations At Valles Caldera - Sulphur Springs Area  

Open Energy Info (EERE)

Roberts, Et Al., 1995) Roberts, Et Al., 1995) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Valles Caldera - Sulphur Springs Area (Roberts, Et Al., 1995) Exploration Activity Details Location Valles Caldera - Sulphur Springs Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Modeling of the amplitude data, using the Aki-Lamer method, confirmed that this anomaly exists and we estimated quantitative parameters defining it. All model parameters were physically meaningful except for one. The value for Q inside the anomaly, required to explain the data, was unrealistically low. This was probably due to the inability to include additional structural complexity within the low-Q zone that would account for a

42

Modeling-Computer Simulations At Dixie Valley Geothermal Field Area  

Open Energy Info (EERE)

Dixie Valley Geothermal Field Area Dixie Valley Geothermal Field Area (Kennedy & Van Soest, 2006) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Dixie Valley Geothermal Field Area (Kennedy & Van Soest, 2006) Exploration Activity Details Location Dixie Valley Geothermal Field Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness could be useful with more improvements DOE-funding Unknown Notes Using a simple one-dimensional steady-state fluid flow model, the helium content and isotopic composition imply vertical fluid flow rates from the mantle of _7 mm/yr. This is a strict lower limit to the fluid flow rate: the one-dimensional model does not consider diffusive re-distribution of helium or mixing with water containing only a crustal helium component and

43

Modeling-Computer Simulations At Central Nevada Seismic Zone Region  

Open Energy Info (EERE)

Central Nevada Seismic Zone Region Central Nevada Seismic Zone Region (Blackwell, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Central Nevada Seismic Zone Region (Blackwell, Et Al., 2003) Exploration Activity Details Location Central Nevada Seismic Zone Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Developed natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dixie Valley data that help to understand the nature of large scale constraints on the location and characteristics of the geothermal systems References D. D. Blackwell, K. W. Wisian, M. C. Richards, Mark Leidig, Richard Smith, Jason McKenna (2003) Geothermal Resource Analysis And Structure Of

44

Modeling-Computer Simulations At Raft River Geothermal Area (1979) | Open  

Open Energy Info (EERE)

Jump to: navigation, search Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Raft River Geothermal Area (1979) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date 1979 Usefulness useful DOE-funding Unknown Exploration Basis To evaluate the hydrodynamics of the unconfined aquifer. Notes This study covers about 1000 mi2 (2600 km2) of the southern Raft River drainage basin in south-central Idaho and northwest Utah. The main area of interest, approximately 200 mi2 (520 km2) of semiarid agricultural and rangeland in the southern Raft River Valley that includes the known Geothermal Resource Area near Bridge, Idaho, was modelled numerically. Computed and estimated transmissivity values range from 1200 ft2 per day

45

Modeling-Computer Simulations At U.S. West Region (Williams ...  

Open Energy Info (EERE)

Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At U.S. West Region (Williams & Deangelo, 2008) Jump to: navigation, search GEOTHERMAL...

46

Modeling-Computer Simulations At U.S. West Region (Sabin, Et...  

Open Energy Info (EERE)

Search Page Edit History Facebook icon Twitter icon Modeling-Computer Simulations At U.S. West Region (Sabin, Et Al., 2004) Jump to: navigation, search GEOTHERMAL...

47

Modeling-Computer Simulations At Northern Basin & Range Region (Pritchett,  

Open Energy Info (EERE)

Modeling-Computer Simulations At Northern Basin & Range Region (Pritchett, Modeling-Computer Simulations At Northern Basin & Range Region (Pritchett, 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Northern Basin & Range Region (Pritchett, 2004) Exploration Activity Details Location Northern Basin and Range Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown References J. W. Pritchett (2004) Finding Hidden Geothermal Resources In The Basin And Range Using Electrical Survey Techniques- A Computational Feasibility Study Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Northern_Basin_%26_Range_Region_(Pritchett,_2004)&oldid=401423"

48

Modeling-Computer Simulations At Northern Basin & Range Region (Biasi, Et  

Open Energy Info (EERE)

Modeling-Computer Simulations At Northern Basin & Range Region (Biasi, Et Modeling-Computer Simulations At Northern Basin & Range Region (Biasi, Et Al., 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Northern Basin & Range Region (Biasi, Et Al., 2009) Exploration Activity Details Location Northern Basin and Range Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful regional reconnaissance DOE-funding Unknown References Glenn Biasi, Leiph Preston, Ileana Tibuleac (2009) Body Wave Tomography For Regional Scale Assessment Of Geothermal Indicators In The Western Great Basin Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Northern_Basin_%26_Range_Region_(Biasi,_Et_Al.,_2009)&oldid=40142

49

Modeling-Computer Simulations At Nw Basin & Range Region (Biasi, Et Al.,  

Open Energy Info (EERE)

Biasi, Et Al., Biasi, Et Al., 2009) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Nw Basin & Range Region (Biasi, Et Al., 2009) Exploration Activity Details Location Northwest Basin and Range Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful regional reconnaissance DOE-funding Unknown References Glenn Biasi, Leiph Preston, Ileana Tibuleac (2009) Body Wave Tomography For Regional Scale Assessment Of Geothermal Indicators In The Western Great Basin Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Nw_Basin_%26_Range_Region_(Biasi,_Et_Al.,_2009)&oldid=401461" Categories: Exploration Activities DOE Funded

50

Modeling-Computer Simulations At Fish Lake Valley Area (Deymonaz, Et Al.,  

Open Energy Info (EERE)

Modeling-Computer Simulations At Fish Lake Valley Area (Deymonaz, Et Al., Modeling-Computer Simulations At Fish Lake Valley Area (Deymonaz, Et Al., 2008) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Fish Lake Valley Area (Deymonaz, Et Al., 2008) Exploration Activity Details Location Fish Lake Valley Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes (4) synthesis of geologic mapping results and lithologic logs for 3_D geologic characterization of the prospect area; (5) compilation of relevant data from the foregoing sub_activities into a Geographic Information Systems (GIS) database for visualization and mapping, and to facilitate the development of an exploration model; and (6) development of a refined

51

Modeling-Computer Simulations At Akutan Fumaroles Area (Kolker, Et Al.,  

Open Energy Info (EERE)

Modeling-Computer Simulations At Akutan Fumaroles Area (Kolker, Et Al., Modeling-Computer Simulations At Akutan Fumaroles Area (Kolker, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Akutan Fumaroles Area (Kolker, Et Al., 2010) Exploration Activity Details Location Akutan Fumaroles Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes "Conceptual Model: Based on conceptual models built primarily from MT and geochemical datasets, it appears that development of the Akutan geothermal resource for power and/or direct use may be feasible. These datasets point to a shallow, tabular aquifer(s) of 155-180degrees C (i.e., "outflow zone") and a deeper, hotter resource of >220degrees C (i.e., "upflow zone") that

52

Modeling-Computer Simulations At Valles Caldera - Redondo Area (Roberts, Et  

Open Energy Info (EERE)

Modeling-Computer Simulations At Valles Caldera - Redondo Area (Roberts, Et Modeling-Computer Simulations At Valles Caldera - Redondo Area (Roberts, Et Al., 1995) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Valles Caldera - Redondo Area (Roberts, Et Al., 1995) Exploration Activity Details Location Valles Caldera - Redondo Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Modeling of the amplitude data, using the Aki-Lamer method, confirmed that this anomaly exists and we estimated quantitative parameters defining it. All model parameters were physically meaningful except for one. The value for Q inside the anomaly, required to explain the data, was unrealistically low. This was probably due to the inability to include additional

53

Modeling-Computer Simulations At San Juan Volcanic Field Area (Clarkson &  

Open Energy Info (EERE)

Modeling-Computer Simulations At San Juan Volcanic Field Area (Clarkson & Modeling-Computer Simulations At San Juan Volcanic Field Area (Clarkson & Reiter, 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At San Juan Volcanic Field Area (Clarkson & Reiter, 1987) Exploration Activity Details Location San Juan Volcanic Field Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes In this study we combine thermal maturation models, based on the level of maturation of the Fruitland Formation coals, and time-dependet temperature models, based on heat-flow data in the San Juan region, to further investigate both the thermal history of the region and the nature of the influence of the San Juan volcanic field thermal source on the thermal

54

Modeling-Computer Simulations At Chocolate Mountains Area (Alm, Et Al.,  

Open Energy Info (EERE)

Modeling-Computer Simulations At Chocolate Mountains Area (Alm, Et Al., Modeling-Computer Simulations At Chocolate Mountains Area (Alm, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Chocolate Mountains Area (Alm, Et Al., 2010) Exploration Activity Details Location Chocolate Mountains Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes "Shallow temperature gradient drilling began at the CMAGR in January of 2010. 13 temperature gradient holes were completed to a depth of 500' below ground surface. Sites were selected based on the compilation of previous exploration and resulting data is being integrated into the most recent geologic model. This model will form the basis for the selection of a

55

Modeling-Computer Simulations At Cove Fort Area (Toksoz, Et Al, 2010) |  

Open Energy Info (EERE)

Modeling-Computer Simulations At Cove Fort Area (Toksoz, Et Al, 2010) Modeling-Computer Simulations At Cove Fort Area (Toksoz, Et Al, 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Cove Fort Area (Toksoz, Et Al, 2010) Exploration Activity Details Location Cove Fort Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes We have collected various geophysical data around the geothermal field, including heat flow, gravity, MT, seismic surface wave phase and group velocity maps, seismic body wave travel time data and full seismic waveforms. All of these geophysical data sets have different strengths on characterizing subsurface structures and properties. Combining these data through a coordinated analysis and, when possible, by joint inversion

56

Modeling-Computer Simulations At Coso Geothermal Area (1980) | Open Energy  

Open Energy Info (EERE)

Modeling-Computer Simulations At Coso Geothermal Area (1980) Modeling-Computer Simulations At Coso Geothermal Area (1980) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Coso Geothermal Area (1980) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date 1980 Usefulness useful DOE-funding Unknown Exploration Basis Estimate thermal regime and potential of the system Notes A three-dimensional generalized linear inversion of the delta t* observations was performed using a three-layer model. A shallow zone of high attenuation exists within the upper 5 km in a region bounded by Coso Hot Springs, Devils Kitchen, and Sugarloaf Mountain probably corresponding to a shallow vapor liquid mixture or "lossy" near surface lithology.

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Modeling-Computer Simulations At Coso Geothermal Area (1999) | Open Energy  

Open Energy Info (EERE)

Modeling-Computer Simulations At Coso Geothermal Area (1999) Modeling-Computer Simulations At Coso Geothermal Area (1999) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Coso Geothermal Area (1999) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date 1999 Usefulness not indicated DOE-funding Unknown Exploration Basis To analyze attenuation and source properties Notes A multiple-empirical Green's function method was used to determine source properties of small (M -0.4 to 1.3) earthquakes and P-wave and S-wave attenuation at the Coso Geothermal Field. Source properties of a previously identified set of clustered events from the Coso geothermal region are first analyzed using an empirical Green's function (EGF) method.

58

Modeling-Computer Simulations At Nw Basin & Range Region (Laney, 2005) |  

Open Energy Info (EERE)

Modeling-Computer Simulations At Nw Basin & Range Region (Laney, 2005) Modeling-Computer Simulations At Nw Basin & Range Region (Laney, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Nw Basin & Range Region (Laney, 2005) Exploration Activity Details Location Northwest Basin and Range Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes Assembling Crustal Geophysical Data for Geothermal Exploration in the Great Basin, Louie and Coolbaugh. We have compiled velocity information from sources in the literature, results of previous seismic experiments and earthquake-monitoring projects, and data donated from mining, geothermal, and petroleum companies. We also collected (May 2002 and August 2004) two

59

Modeling-Computer Simulations At Coso Geothermal Area (2000) | Open Energy  

Open Energy Info (EERE)

Modeling-Computer Simulations At Coso Geothermal Area (2000) Modeling-Computer Simulations At Coso Geothermal Area (2000) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Coso Geothermal Area (2000) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date 2000 Usefulness not indicated DOE-funding Unknown Exploration Basis Model ground subsidence using observations of satellite radar interferometry Notes The InSAR displacement data was inverted for the positions, geometry, and relative strengths of the deformation sources at depth using a nonlinear least squares minimization algorithm. Elastic solutions were used for a prolate uniformly pressurized spheroidal cavity in a semi-infinite body as

60

Modeling-Computer Simulations At Hawthorne Area (Lazaro, Et Al., 2010) |  

Open Energy Info (EERE)

Modeling-Computer Simulations At Hawthorne Area (Lazaro, Et Al., 2010) Modeling-Computer Simulations At Hawthorne Area (Lazaro, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Hawthorne Area (Lazaro, Et Al., 2010) Exploration Activity Details Location Hawthorne Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes The Navy GPO has contracted the University of Nevada Reno Great Basin for Center for Geothermal Research to conduct additional field exploration at HAD. The tasks required by the Navy range from field mapping and water sampling; detailed mapping, to low angle sun photo interpretations, trenching, to 3-D seismic interpretations and modeling. References Michael Lazaro, Chris Page, Andy Tiedeman, Andrew Sabin, Steve

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Modeling-Computer Simulations At Raft River Geothermal Area (1977) | Open  

Open Energy Info (EERE)

Raft River Geothermal Area (1977) Raft River Geothermal Area (1977) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Raft River Geothermal Area (1977) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date 1977 Usefulness not indicated DOE-funding Unknown Exploration Basis Simulate reservoir performance Notes Computer models describing both the transient reservoir pressure behavior and the time dependent temperature response of the wells were developed. A horizontal, two-dimensional, finite-difference model for calculating pressure effects was constructed to simulate reservoir performance. Vertical, two-dimensional, finite-difference, axisymmetric models for each

62

Modeling-Computer Simulations At Nevada Test And Training Range Area  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Modeling-Computer Simulations At Nevada Test And Training Range Area (Sabin, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Nevada Test And Training Range Area (Sabin, Et Al., 2004) Exploration Activity Details Location Nevada Test And Training Range Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes Nellis Air Force Range (NAFR) occupies over 3 million acres in southern Nevada (Figure 1). We recently assessed potential utility-grade geothermal

63

Modeling-Computer Simulations At Nw Basin & Range Region (Blackwell, Et  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Modeling-Computer Simulations At Nw Basin & Range Region (Blackwell, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Nw Basin & Range Region (Blackwell, Et Al., 2003) Exploration Activity Details Location Northwest Basin and Range Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Developed natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dixie Valley data that help to

64

Modeling-Computer Simulations At Obsidian Cliff Area (Hulen, Et Al., 2003)  

Open Energy Info (EERE)

Obsidian Cliff Area (Hulen, Et Al., 2003) Obsidian Cliff Area (Hulen, Et Al., 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Obsidian Cliff Area (Hulen, Et Al., 2003) Exploration Activity Details Location Obsidian Cliff Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown References Jeff Hulen, Denis Norton, Dennis Kaspereit, Larry Murray, Todd van de Putte, Melinda Wright (2003) Geology And A Working Conceptual Model Of The Obsidian Butte (Unit 6) Sector Of The Salton Sea Geothermal Field, California Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Obsidian_Cliff_Area_(Hulen,_Et_Al.,_2003)&oldid=388945" Category: Exploration

65

Modeling-Computer Simulations At Long Valley Caldera Area (Pribnow, Et Al.,  

Open Energy Info (EERE)

2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Long Valley Caldera Area (Pribnow, Et Al., 2003) Exploration Activity Details Location Long Valley Caldera Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes Several fluid-flow models presented regarding the Long Valley Caldera. At shallow depths in the caldera References Daniel F. C. Pribnow, Claudia Schutze, Suzanne J. Hurter, Christina Flechsig, John H. Sass (2003) Fluid Flow In The Resurgent Dome Of Long Valley Caldera- Implications From Thermal Data And Deep Electrical Sounding Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Long_Valley_Caldera_Area_(Pribnow,_Et_Al.,_2003)&oldid=389388

66

Modeling-Computer Simulations At Fenton Hill Hdr Geothermal Area (Heiken &  

Open Energy Info (EERE)

Heiken & Heiken & Goff, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Fenton Hill Hdr Geothermal Area (Heiken & Goff, 1983) Exploration Activity Details Location Fenton Hill Hdr Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes Development of a geologically-based model of the thermal and hydrothermal potential of the Fenton Hill HDR area. References Grant Heiken, Fraser Goff (1983) Hot Dry Rock Geothermal Energy In The Jemez Volcanic Field, New Mexico Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Fenton_Hill_Hdr_Geothermal_Area_(Heiken_%26_Goff,_1983)&oldid=511328

67

Modeling-Computer Simulations At General Us Region (Goff & Decker, 1983) |  

Open Energy Info (EERE)

Us Region (Goff & Decker, 1983) Us Region (Goff & Decker, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At General Us Region (Goff & Decker, 1983) Exploration Activity Details Location General Us Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Review and identification of 24 potential sites for EGS development across the U.S., as well as modeling of the representative geologic systems in which promising EGS sites occur. References Fraser Goff, Edward R. Decker (1983) Candidate Sites For Future Hot Dry Rock Development In The United States Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_General_Us_Region_(Goff_%26_Decker,_1983)&oldid=38761

68

Modeling-Computer Simulations At Geysers Area (Goff & Decker, 1983) | Open  

Open Energy Info (EERE)

Decker, 1983) Decker, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Geysers Area (Goff & Decker, 1983) Exploration Activity Details Location Geysers Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Review and identification of 24 potential sites for EGS development across the U.S., as well as modeling of the representative geologic systems in which promising EGS sites occur. References Fraser Goff, Edward R. Decker (1983) Candidate Sites For Future Hot Dry Rock Development In The United States Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Geysers_Area_(Goff_%26_Decker,_1983)&oldid=38676

69

Modeling-Computer Simulations At White Mountains Area (Goff & Decker, 1983)  

Open Energy Info (EERE)

White Mountains Area (Goff & Decker, 1983) White Mountains Area (Goff & Decker, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At White Mountains Area (Goff & Decker, 1983) Exploration Activity Details Location White Mountains Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Review and identification of 24 potential sites for EGS development across the U.S., as well as modeling of the representative geologic systems in which promising EGS sites occur. References Fraser Goff, Edward R. Decker (1983) Candidate Sites For Future Hot Dry Rock Development In The United States Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_White_Mountains_Area_(Goff_%26_Decker,_1983)&oldid=387355"

70

Modeling-Computer Simulations At Fenton Hill Hdr Geothermal Area (Goff &  

Open Energy Info (EERE)

Decker, 1983) Decker, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Fenton Hill Hdr Geothermal Area (Goff & Decker, 1983) Exploration Activity Details Location Fenton Hill Hdr Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Review and identification of 24 potential sites for EGS development across the U.S., as well as modeling of the representative geologic systems in which promising EGS sites occur. References Fraser Goff, Edward R. Decker (1983) Candidate Sites For Future Hot Dry Rock Development In The United States Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Fenton_Hill_Hdr_Geothermal_Area_(Goff_%26_Decker,_1983)&oldid=511326"

71

Modeling-Computer Simulations At Walker-Lane Transitional Zone Region  

Open Energy Info (EERE)

Modeling-Computer Simulations At Walker-Lane Modeling-Computer Simulations At Walker-Lane Transitional Zone Region (Laney, 2005) Exploration Activity Details Location Walker-Lane Transition Zone Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness not indicated DOE-funding Unknown Notes Assembling Crustal Geophysical Data for Geothermal Exploration in the Great Basin, Louie and Coolbaugh. We have compiled velocity information from sources in the literature, results of previous seismic experiments and earthquake-monitoring projects, and data donated from mining, geothermal, and petroleum companies. We also collected (May 2002 and August 2004) two new crustal refraction profiles across western Nevada and the northern and central Sierra. These sections had not been well characterized previously.

72

Modeling-Computer Simulations At Raft River Geothermal Area (1980) | Open  

Open Energy Info (EERE)

80) 80) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Raft River Geothermal Area (1980) Exploration Activity Details Location Raft River Geothermal Area Exploration Technique Modeling-Computer Simulations Activity Date 1980 Usefulness not indicated DOE-funding Unknown Exploration Basis From refined estimates of reservoir coefficients better predictions of interference effects and long-term drawdown in the wells can be made. Notes Analytic methods have been used during reservoir testing to calculate reservoir coefficients. However, anisotropy of the reservoir due to fractures has not been taken into account in these calculations and estimates of these coefficients need to be refined. In conjunction with the

73

Residual Stresses and Numerical Simulation  

Science Conference Proceedings (OSTI)

Oct 28, 2013 ... Advances in Hydroelectric Turbine Manufacturing and Repair: Residual Stresses and Numerical Simulation Sponsored by: Metallurgical...

74

Modeling-Computer Simulations At Northern Basin & Range Region (Blackwell,  

Open Energy Info (EERE)

Northern Basin & Northern Basin & Range Region (Blackwell, Et Al., 2003) Exploration Activity Details Location Northern Basin and Range Geothermal Region Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Developed natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dixie Valley data that help to understand the nature of large scale constraints on the location and characteristics of the geothermal systems References D. D. Blackwell, K. W. Wisian, M. C. Richards, Mark Leidig, Richard Smith, Jason McKenna (2003) Geothermal Resource Analysis And Structure Of Basin And Range Systems, Especially Dixie Valley Geothermal Field, Nevada Retrieved from "http://en.openei.org/w/index.php?title=Modeling-Computer_Simulations_At_Northern_Basin_%26_Range_Region_(Blackwell,_Et_Al.,_2003)&oldid=401422

75

Modeling-Computer Simulations At Kilauea East Rift Area (Rudman & Epp,  

Open Energy Info (EERE)

Rudman & Epp, Rudman & Epp, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Kilauea East Rift Area (Rudman & Epp, 1983) Exploration Activity Details Location Kilauea East Rift Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Three models were generated: a constant temperature source from a vertical dike; a constant heat-generating magma chamber; and a transient heat source from a tapered vertical dike. Fair correlation is obtained between the HGP-A well temperature and the tapered dike 125 years after it is injected with an initial (transient) 1200degrees C temperature. Results provide background information from which to evaluate the importance of water

76

Modeling-Computer Simulations At Long Valley Caldera Area (Farrar, Et Al.,  

Open Energy Info (EERE)

3) 3) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Long Valley Caldera Area (Farrar, Et Al., 2003) Exploration Activity Details Location Long Valley Caldera Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness useful DOE-funding Unknown Notes Modeling of both deformation and microgravity data now suggests that (1) there are two inflation sources beneath the caldera, a shallower source 7^10 km beneath the resurgent dome and a deeper source V15 km beneath the caldera's south moat and (2) the shallower source may contain components of magmatic brine and gas. At shallow depths in the caldera References Christopher D. Farrar, Michael L. Sorey, Evelyn Roeloffs, Devin L.

77

Modeling-Computer Simulations At Valles Caldera - Redondo Area (Wilt &  

Open Energy Info (EERE)

Redondo Area (Wilt & Redondo Area (Wilt & Haar, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Modeling-Computer Simulations At Valles Caldera - Redondo Area (Wilt & Haar, 1986) Exploration Activity Details Location Valles Caldera - Redondo Area Exploration Technique Modeling-Computer Simulations Activity Date Usefulness could be useful with more improvements DOE-funding Unknown Notes A computer program capable of two-dimensional modeling of gravity data was used in interpreting gravity observations along profiles A--A' and B--B' (Talwani et al., 1959). Densities of 2.12, 2.40, and 2.65 g/cm a were used for modeling the near-surface caldera fill, the underlying volcanics, and the basement sections, respectively (Fig. 8). Although correlation with

78

Factor Separation in Numerical Simulations  

Science Conference Proceedings (OSTI)

A simple method is developed for computing the interactions among various factors influencing the atmospheric circulations. It is shown how numerical simulations can be utilized to obtain the pure contribution of any factor to any predicted field,...

U. Stein; P. Alpert

1993-07-01T23:59:59.000Z

79

INTERNATIONAL JOURNAL OF c 2004 Institute for Scientific NUMERICAL ANALYSIS AND MODELING Computing and Information  

E-Print Network (OSTI)

., Petroelum Reservoir Simulation, Applied Science Publisher Ltd, 1979. [4] Baker A.A., Gelhar L.W., Gutjahr A

Ewing, Richard E.

80

Numerical Simulations of Black Holes  

E-Print Network (OSTI)

Numerical Simulations of Black Holes 26 Aug 2009 Frank Herrmann (fherrman@umd.edu) Department · merger of compact objects Much more than just black hole evolutions · Formulations · Hyperboloidal)/2.0; . . . high arithmetic intensity Operator Number of times used 12,961 + 5,398 - 3,438 / 69 14 #12;Black Hole

Maryland at College Park, University of

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Numerical simulation of reservoir compaction in liquid dominated geothermal systems  

DOE Green Energy (OSTI)

A numerical model is introduced which simulates the effects of fluid production as well as reinjection on the vertical deformation of water dominated geothermal reservoirs. This program, based on an Integrated Finite Difference technique and Terzaghi's one-dimensional consolidation model, computes the transport of heat and water through porous media, and resulting pore volume changes. Examples are presented to show the effects of reservoir heterogeneities on the compaction of these hot water systems, as well as the effects of different production-injection schemes. The use of isothermal models to simulate the deformation of non-isothermal systems was also investigated.

Lippmann, M.J.; Narasimhan, T.N.; Witherspoon, P.A.

1976-12-01T23:59:59.000Z

82

Numerical Simulation of Macrosegregation Formation during ...  

Science Conference Proceedings (OSTI)

Direct Numerical Simulation of Inclusion Turbulent Deposition at Liquid ... Flow and Shrinkage Pipe Formation on Macrosegregation of Investment Cast -TiAl Alloys ... Numerical Modeling of the Interaction between a Foreign Particle an...

83

Numerical simulations of strong gravitational fields  

Science Conference Proceedings (OSTI)

Solutions to the Einstein equations of general relativity are constructed using numerical methods on high performance computing platforms. This article reviews the methods used to obtain numerical solutions to the Einstein equations and discusses some results from recent numerical simulations of highly nonlinear cosmological spacetimes as well as for time dependent black holes that emit gravitational waves.

David W. Hobill

1995-01-01T23:59:59.000Z

84

Numeric simulation of faults in electrical networks  

Science Conference Proceedings (OSTI)

In the paper is presented a virtual simulator for three-phased medium voltage electric circuits. The simulator allows analyzing transient regimes caused by the faults produced in electric distribution networks (simple grounding, double grounding, broken ... Keywords: faults in electric network, numerical simulation, three phased circuits, transient regimes

Toader Dumitru; Haragus Stefan; Blaj Constantin

2009-03-01T23:59:59.000Z

85

Numerical wind speed simulation model  

DOE Green Energy (OSTI)

A relatively simple stochastic model for simulating wind speed time series that can be used as an alternative to time series from representative locations is described in this report. The model incorporates systematic seasonal variation of the mean wind, its standard deviation, and the correlation speeds. It also incorporates systematic diurnal variation of the mean speed and standard deviation. To demonstrate the model capabilities, simulations were made using model parameters derived from data collected at the Hanford Meteorology Station, and results of analysis of simulated and actual data were compared.

Ramsdell, J.V.; Athey, G.F.; Ballinger, M.Y.

1981-09-01T23:59:59.000Z

86

Numerical Simulations of Maritime Frontogenesis  

Science Conference Proceedings (OSTI)

A hydrostatic primitive equation model initialized in a highly baroclinically unstable state was used to simulate maritime cyclogenesis and frontogenesis. In order to identify boundary layer physical processes important in maritime frontogenesis, ...

William T. Thompson; R. T. Williams

1997-01-01T23:59:59.000Z

87

Numerical Simulation of Sudden Stratospheric Warmings  

Science Conference Proceedings (OSTI)

A mechanistic, quasi-geostrophic, semi-spectral model with a self-consistent calculation of the mean zonal flow fields is used to numerically simulate sudden stratospheric warmings generated by a single zonal harmonic (m) planetary wave. The ...

Mark R. Schoeberl; Darrell F. Strobel

1980-01-01T23:59:59.000Z

88

Numerical simulation of the active magnetic regenerator  

Science Conference Proceedings (OSTI)

A time-dependent one-dimensional model of the active magnetic regenerator (AMR) that takes into account most of the physical and practical design problems for the AMR is developed as a highly nonlinear system of partial differential equations. The adequateness ... Keywords: Active magnetic regenerator, Magnetic refrigerator, Modeling and numerical scheme, Numerical simulation, Passive regenerator

B. M. Siddikov; B. A. Wade; D. H. Schultz

2005-05-01T23:59:59.000Z

89

A numerical sensitivity analysis of streamline simulation  

E-Print Network (OSTI)

Nowadays, field development strategy has become increasingly dependent on the results of reservoir simulation models. Reservoir studies demand fast and efficient results to make investment decisions that require a reasonable trade off between accuracy and simulation time. One of the suitable options to fulfill this requirement is streamline reservoir simulation technology, which has become very popular in the last few years. Streamline (SL) simulation provides an attractive alternative to conventional reservoir simulation because SL offers high computational efficiency and minimizes numerical diffusion and grid orientation effects. However, streamline methods have weaknesses incorporating complex physical processes and can also suffer numerical accuracy problems. The main objective of this research is to evaluate the numerical accuracy of the latest SL technology, and examine the influence of different factors that may impact the solution of SL simulation models. An extensive number of numerical experiments based on sensitivity analysis were performed to determine the effects of various influential elements on the stability and results of the solution. Those experiments were applied to various models to identify the impact of factors such as mobility ratios, mapping of saturation methods, number of streamlines, time step sizes, and gravity effects. This study provides a detailed investigation of some fundamental issues that are currently unresolved in streamline simulation.

Chaban Habib, Fady Ruben

2004-12-01T23:59:59.000Z

90

Numerical Simulations of the Wake of Kauai  

Science Conference Proceedings (OSTI)

This study uses a series of numerical simulations to examine the structure of the wake of the Hawaiian island of Kauai. The primary focus is on the conditions on 26 June 2003, which was the day of the demise of the Helios aircraft within Kauais ...

Todd P. Lane; Robert D. Sharman; Rod G. Frehlich; John M. Brown

2006-09-01T23:59:59.000Z

91

Direct numerical simulation of evaporating droplets  

Science Conference Proceedings (OSTI)

A model for the three-dimensional direct numerical simulation of evaporating, deforming droplets in incompressible flow is presented. It is based on the volume-of-fluid method and is therefore capable of capturing very strong deformations. The evaporation ... Keywords: DNS, Deformed droplets, Evaporation, Multiphase flow, Stefan flow, VOF

Jan Schlottke; Bernhard Weigand

2008-05-01T23:59:59.000Z

92

Numerical simulation of an electroweak oscillon  

Science Conference Proceedings (OSTI)

Numerical simulations of the bosonic sector of the SU(2)xU(1) electroweak standard model in 3+1 dimensions have demonstrated the existence of an oscillon--an extremely long-lived, localized, oscillatory solution to the equations of motion--when the Higgs mass is equal to twice the W{sup {+-}} boson mass. It contains total energy roughly 30 TeV localized in a region of radius 0.05 fm. A detailed description of these numerical results is presented.

Graham, N. [Department of Physics, Middlebury College, Middlebury, Vermont 05753 (United States)

2007-10-15T23:59:59.000Z

93

Numerical techniques of rigid body simulation  

E-Print Network (OSTI)

In recent years, the modeling of physical phenomena has become an integral part of computer applications in diverse areas from engineering to entertainment. This thesis focuses on a particular aspect of this modeling, the simulation of rigid bodies. Complicated simulations require the development of sophisticated collision detection systems and numerical techniques. Previous work in the field has almost exclusively been restricted to geometries that are convex or a union of convex pieces. One of the goals of this thesis is overcoming this restriction. Collision detection is only one of the many hurdles which arise in simulating collisions between rigid bodies. To calculate the appropriate response of colliding bodies, the point of contact between the bodies must be determined. Methods of contact point determination will also be discussed. This thesis also explores the issues of resolving simultaneous collisions and resting contact via the formulation of a linear complementarity problem (LCP). This method maintains the physical validity of the simulator, unlike penalty methods which are often used. Impulse based methods for resting contacts have been proposed and implemented by others, but cannot simulate simple structures, such as a stack of blocks. The LCP formulation allows these types of configurations, which are successfully simulated in this thesis. The culmination of this thesis is the development of a rigid body simulator. The numerical methods and algorithms employed are discussed and are compared to alternative techniques. The intention is that the reader use this thesis and its references to ease the process of writing a new simulator and gain insight into the methods used.

Eberle, David Michael

2001-01-01T23:59:59.000Z

94

Numerical simulation of the solar granulation  

Science Conference Proceedings (OSTI)

The solar granulation has been simulated by numerical solution of the multidimensional, time-dependent, nonlinear Navier-Stokes equations applied to the solar atmosphere. Granules may be explained as buoyantly rising bubbles created at the level where T = 8000 K, and which have collapsed into vortex rings. The calculation is in quantitative agreement with observations and has a number of implications for solar physics and convection theory.

Cloutman, L.D.

1980-08-01T23:59:59.000Z

95

Numerical simulation of magma energy extraction  

DOE Green Energy (OSTI)

The Magma Energy Program is a speculative endeavor regarding practical utility of electrical power production from the thermal energy which reside in magma. The systematic investigation has identified an number of research areas which have application to the utilization of magma energy and to the field of geothermal energy. Eight topics were identified which involve thermal processes and which are areas for the application of the techniques of numerical simulation. These areas are: (1) two-phase flow of the working fluid in the wellbore, (2) thermodynamic cycles for the production of electrical power, (3) optimization of the entire system, (4) solidification and fracturing of the magma caused by the energy extraction process, (5) heat transfer and fluid flow within an open, direct-contact, heat-exchanger, (6) thermal convection in the overlying geothermal region, (7) thermal convection within the magma body, and (8) induced natural convection near the thermal energy extraction device. Modeling issues have been identified which will require systematic investigation in order to develop the most appropriate strategies for numerical simulation. It appears that numerical simulations will be of ever increasing importance to the study of geothermal processes as the size and complexity of the systems of interest increase. It is anticipated that, in the future, greater emphasis will be placed on the numerical simulation of large-scale, three-dimensional, transient, mixed convection in viscous flows and porous media. Increased computational capabilities, e.g.; massively parallel computers, will allow for the detailed study of specific processes in fractured media, non-Darcy effects in porous media, and non-Newtonian effects. 23 refs., 13 figs., 1 tab.

Hickox, C.E.

1991-01-01T23:59:59.000Z

96

Numerical Simulation of Electro-magnetic Turbulent Inhibitor ...  

Science Conference Proceedings (OSTI)

Numerical Modeling of Centrifugally Cast HSS Rolls Numerical Simulation of Electro-magnetic Turbulent Inhibitor Technology in a Tundish Optimizing the...

97

Numerical simulations to study solar wind turbulence  

Science Conference Proceedings (OSTI)

Numerical simulation of coupled equations of kinetic Alfven wave (KAW) and ion acoustic wave is presented in the solar wind. The nonlinear dynamical equations satisfy the modified Zakharov system of equations by taking the nonadiabatic response of the background density. The ponderomotive nonlinearity is incorporated in the wave dynamics. The effect of Landau damping of KAW is taken into account. Localization of magnetic field intensity and the wavenumber spectra (perpendicular and parallel) of magnetic fluctuations are studied in solar plasmas around 1 a.u. Our results reveal the formation of damped localized structures and the steeper spectra that are in good agreement with the observations. These damped structures and steeper turbulent spectra can be responsible for plasma heating and particle acceleration in solar wind.

Sharma, R. P.; Sharma, Nidhi; Kumar, Sanjay [Centre for Energy Studies, Indian Institute of Technology Delhi, Delhi 110016 (India); Kumar, Sachin [Department of Applied Sciences and Humanities, Ajay Kumar Garg Engineering College, Ghaziabad 201009 (India); Singh, H. D. [Department of Physical Sciences, School of Physical and Chemical Sciences, Sikkim University, Sikkim 737102 (India)

2011-02-15T23:59:59.000Z

98

Numerical simulation of fueling in tokamaks  

DOE Green Energy (OSTI)

We describe the numerical simulation of fueling and particle transport in both present and future tokamak plasmas. Models for pellet ablation and plasma density behavior after pellet injection are compared with experimental results in ISX and PDX plasmas and then extended to fusion reactor conditions. The role of fast ion ablation due to intense neutral beam injection and fusion alphas is examined along with pellet size and velocity considerations. In plasmas with high pumping efficiency (which may be obtained with divertor operation), pellet injection can significantly reduce fueling rates while maintaining more flexibility in control of the density profile than afforded by gas puffing. When fueling is dominated by gas puffing or high recycle from the walls or limiter, control of the fueling and density profiles is reduced and particle fluxes to the wall increase.

Attenberger, S.E.; Houlberg, W.A.; Milora, S.L.

1982-04-01T23:59:59.000Z

99

Numerical Simulation Methods Used at VNIIEF for Numerical Simulation Methods Used at VNIIEF for  

National Nuclear Security Administration (NNSA)

61 61 Numerical Simulation Methods Used at VNIIEF for Numerical Simulation Methods Used at VNIIEF for Multidimensional Radiation and Particle Transport Problems Multidimensional Radiation and Particle Transport Problems R.M. R.M. Shagaliev Shagaliev RFNC-VNIIEF, 607190, RFNC-VNIIEF, 607190, Sarov Sarov, , Nizhni Nizhni Novgorod region Novgorod region Joint Russian-American Five-Laboratory Conference on Computation Joint Russian-American Five-Laboratory Conference on Computation Mathematics|Physics Mathematics|Physics 19-23 June 2005, 19-23 June 2005, Crowne Crowne Plaza, Vienna, Austria Plaza, Vienna, Austria Russian Federal Nuclear Center - VNIIEF Institute of Theoretical Institute of Theoretical and Mathematical and Mathematical Physics Physics 2 of 61 Abstract

100

Numerical Simulation of Inertia Welding of Inconel 718 (Abstract)  

Science Conference Proceedings (OSTI)

Edison Joining Technology Centre, 1250 Arthur E. Adams Drive,. Columbus, OH 43221. Abstract. This paper presents the results of numerical simulations and...

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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
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101

Numerical Simulation of the Irish Wind Climate and Comparison...  

Open Energy Info (EERE)

Numerical Simulation of the Irish Wind Climate and Comparison with Wind Atlas Data

(Abstract):The wind climate of Ireland has been calculated using the...

102

Numerical Simulations of Wire and Foil Behaviors under Megaampere...  

National Nuclear Security Administration (NNSA)

2: High Energy Density, Plasmas, Magnetic Fields Numerical Simulations of Wire and Foil Electrical Explosion under Helical EMG Current Drive for Warm Dense Matter Generation S.F....

103

Numerical Simulation and Modelling of Electronic and Biochemical Systems  

Science Conference Proceedings (OSTI)

Numerical simulation and modelling are witnessing a resurgence. Designing systems with integrated wireless components, mixed-signal blocks and nanoscale, multi-GHz "digital" circuits is requiring extensive low-level modelling and simulation. Analysis ...

Jaijeet Roychowdhury

2009-02-01T23:59:59.000Z

104

Numerical Simulation and Optimal Control of Air Separation Plants  

E-Print Network (OSTI)

Numerical simulation has already become an indispensable tool in the chemical engineering industry. In this paper, the extension of an already existing simulation package to the efficient and reliable solution of optimal control problems for optimal plant operation is discussed.

Gabriele Engl; Andreas Krner; Thomas Kronseder; Oskar von Stryk

1999-01-01T23:59:59.000Z

105

Numerical Simulation of Thermomechanical Processes Coupled ...  

Science Conference Proceedings (OSTI)

Atomistic Simulation Studies of Materials Interfaces: Recent Insights and .... Thermochemical Models and Phase Equilibria of Urania Rare Earth Fluorite Phases.

106

Numerical simulations of oblique penetration into reinforced concrete targets  

Science Conference Proceedings (OSTI)

A dynamic constitutive model based on the tensile and the compressive damage models for concrete was developed and implemented into the three-dimensional finite element code, LS-DYNA. Numerical simulations of oblique penetration into reinforced concrete ... Keywords: Dynamic damage model, Numerical simulation, Oblique penetration, Reinforced concrete

Yan Liu; Fenglei Huang; Aie Ma

2011-04-01T23:59:59.000Z

107

Computational aspects in numerical simulation of skin tissues  

Science Conference Proceedings (OSTI)

The aim of this paper is to present some computational aspects in numerical simulation of the human skin tissue. A multi-layered model is considered for the skin tissue with emphasis on the mathematical modelling and numerical models in space 2D and ... Keywords: biothermomechanics, coupled problems, finite element method, numerical methods, skin tissue, thermal systems

Iulia Maria Crstea; Ion Crstea

2010-04-01T23:59:59.000Z

108

Numerical Simulations of Hurricane-Generated Currents  

Science Conference Proceedings (OSTI)

The work described here involves the application of a three-dimensional numerical circulation model to the hindcasting of currents generated during two stormsTropical Storm Delia and Hurricane Anita. Reasonably high-quality current and other ...

Cortis Cooper; Bryan Pearce

1982-10-01T23:59:59.000Z

109

Cloud Interactions and Merging: Numerical Simulations  

Science Conference Proceedings (OSTI)

A total of 48 numerical experiments have been performed to study cloud interactions and merging by means of a two-dimensional multi-cell model. Two soundings of deep convection during GATE and two different magnitudes of large-scale lifting.have ...

Wei-Kuo Tao; Joanne Simpson

1984-10-01T23:59:59.000Z

110

Polarization transmission at RHIC, numerical simulations  

SciTech Connect

Typical tracking simulations regarding the transmission of the polarization in the proton-proton collider RHIC are discussed. They participate in general studies aimed at understanding and improving polarization performances during polarized proton-proton runs.

Meot F.; Bai, M.; Liu, C.; Minty, M.; Ranjbar, V.

2012-05-20T23:59:59.000Z

111

Numerical simulations on electrostatic hydrogen cyclotron instabilities  

DOE Green Energy (OSTI)

Both one- and two-dimensional particle simulation models have been used to study the nonlinear behavior of the electrostatic hydrogen cyclotron instabilities driven by the electron current along magnetic field. It is found that the instability saturates as a result of electron velocity space diffusion along magnetic field. The cyclotron waves remain highly coherent in the nonlinear stage. When the electron drift speed is comparable to thermal speed, substantial ion heating as well as particle cross-field diffusion comparable to Bohm diffusion has been observed. Comparisons of the simulation results with the theoretical predictions and the observations in both laboratory and space plasmas are discussed.

Okuda, H.; Cheng, C.Z.; Lee, W.W.

1981-02-01T23:59:59.000Z

112

Numerical Simulation of Mesoscale Eddies over Melbourne  

Science Conference Proceedings (OSTI)

A mesoscale wind field model is used to simulate a cyclonic nocturnal eddy which may form over Melbourne under stable conditions with light synoptic winds. Two types of eddy (Mel-I and Mel-II) are identified, with separate formation mechanisms. ...

John L. McGregor; Fujio Kimura

1989-01-01T23:59:59.000Z

113

Wintertime Supercell Thunderstorms in a Subtropical Environment: Numerical Simulation  

Science Conference Proceedings (OSTI)

Following an earlier diagnostic study, the present paper performs numerical simulations of the rare wintertime supercell storms during 1920 December 2002 in a subtropical environment near Taiwan. Using Japan Meteorology Agency (JMA) 20-km ...

Chung-Chieh Wang; George Tai-Jen Chen; Shan-Chien Yang; Kazuhisa Tsuboki

2009-07-01T23:59:59.000Z

114

Numerical Simulation of a Midlatitude Squall Line in Two Dimensions  

Science Conference Proceedings (OSTI)

A two-dimensional, anelastic cloud model was used in attempts to numerically replicate the observed structure of a midlatitude squall line. Initial conditions were adapted from observations of the 22 May 1976 Oklahoma line. Model simulations were ...

Robert G. Fovell; Yoshi Ogura

1988-12-01T23:59:59.000Z

115

Numerical Simulation of AirSea Coupling during Coastal Upwelling  

Science Conference Proceedings (OSTI)

Airsea coupling during coastal upwelling was examined through idealized three-dimensional numerical simulations with a coupled atmosphereocean mesoscale model. Geometry, topography, and initial and boundary conditions were chosen to be ...

Natalie Perlin; Eric D. Skyllingstad; Roger M. Samelson; Philip L. Barbour

2007-08-01T23:59:59.000Z

116

Numerical simulation of tower rotor interaction for downwind wind turbine  

Science Conference Proceedings (OSTI)

Downwind wind turbines have lower upwind rotormisalignment, and thus lower turning moment and self-steered advantage over the upwind configuration. In this paper, numerical simulation to the downwind turbine is conducted to investigate the interaction ...

Isam Janajreh; Ilham Talab; Jill Macpherson

2010-01-01T23:59:59.000Z

117

Numerical Simulation of CloudClear Air Interfacial Mixing  

Science Conference Proceedings (OSTI)

This paper discusses results from a series of direct numerical simulations of the microscale cloudclear air mixing, set forth in the idealized scenario of decaying moist turbulence. In the moist case, kinetic energy of microscale motions comes ...

Miros?aw Andrejczuk; Wojciech W. Grabowski; Szymon P. Malinowski; Piotr K. Smolarkiewicz

2004-07-01T23:59:59.000Z

118

Incompressible and Anelastic Flow Simulations on Numerically Generated Grids  

Science Conference Proceedings (OSTI)

In the numerical simulation of incompressible and anelastic flows, it is necessary to solve an elliptic equation at each time step. When the boundaries of such flows are nonrectangular, it may be advantageous to solve the equations on a new, ...

R. D. Sharman; T. L. Keller; M. G. Wurtele

1988-05-01T23:59:59.000Z

119

Numerical simulation of thermal response of the skin tissues  

Science Conference Proceedings (OSTI)

The aim of this paper is to develop a numerical model for the simulation the heat transfer process and the heat-induced mechanical response of the skin tissues. We present some models using the finite element method in 2D space. A multilayer model is ... Keywords: biothermomechanics, coupled problems, finite element method, numerical methods, skin tissue, thermal systems

Iulia Maria Crstea; Ion Crstea

2009-12-01T23:59:59.000Z

120

The Numerical Simulation of Conventional Ground Coalbed Methane Development  

Science Conference Proceedings (OSTI)

The migration, accumulation, and production of coalbed methane (CBM) are absolutely different from the conventional natural gas. The mechanism of the migration and production of CBM are researched and the geological model of CBM reservoir simulation ... Keywords: coalbed methane, numerical simulation, desportion-diffusion, two phase flow, fully implicit finite difference

Lin Xiaoying; Liu Guowei; Su Xianbo

2009-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Numerical Simulation of Blasting Demolition of 16-Storied Structure  

Science Conference Proceedings (OSTI)

The separate element and common node model is setup to simulate reinforced concrete material at first, which could take fully account of the intensity difference of concrete and rebar. And then a 16-storied frame structure is build with this kind of ... Keywords: blasting demoLition, separate element, common node, unidirectional folding collapse, numerical simulation

Guo-liang Yang; Lin-lin Jiang; Chuan Huo

2011-08-01T23:59:59.000Z

122

Numerical Simulation of Multicomponent Ion Beam from Ion Sources  

E-Print Network (OSTI)

A program library for numerical simulation of a multicomponent charged particle beam from ion sources is presented. The library is aimed for simulation of high current, low energy multicomponent ion beam from ion source through beamline and realized under the Windows user interface for the IBM PC. It is used for simulation and optimization of beam dynamics and based on successive and consistent application of two methods: the momentum method of distribution function (RMS technique) and particle in cell method. The library has been used to simulate and optimize the transportation of tantalum ion beam from the laser ion source (CERN) and calcium ion beam from the ECR ion source (JINR, Dubna).

Alexandrov, V S; Kazarinov, Yu M; Shevtsov, V P; Shirkov, G D

1999-01-01T23:59:59.000Z

123

Numerical simulation of water flow around a rigid fishing net  

E-Print Network (OSTI)

This paper is devoted to the simulation of the flow around and inside a rigid axisymmetric net. We describe first how experimental data have been obtained. We show in detail the modelization. The model is based on a Reynolds Averaged Navier-Stokes turbulence model penalized by a term based on the Brinkman law. At the out-boundary of the computational box, we have used a "ghost" boundary condition. We show that the corresponding variational problem has a solution. Then the numerical scheme is given and the paper finishes with numerical simulations compared with the experimental data.

Roger Lewandowski; Graldine Pichot

2006-12-20T23:59:59.000Z

124

Numerical simulation of graphene in external magnetic field  

E-Print Network (OSTI)

In this paper the results of numerical simulation of monolayer graphene in external magnetic field are presented. The numerical simulation is performed in the effective lattice field theory with noncompact $3 + 1$-dimensional Abelian lattice gauge fields and $2 + 1$-dimensional staggered lattice fermions. The dependences of fermion condensate and graphene conductivity on the dielectric permittivity of substrate for different values of external magnetic field are calculated. It is found that magnetic field shifts insulator-semimetal phase transition to larger values of the dielectric permittivity of substrate. The phase diagram of graphene in external magnetic field is drawn.

D. L. Boyda; V. V. Braguta; S. N. Valgushev; M. I. Polikarpov; M. V. Ulybyshev

2013-08-13T23:59:59.000Z

125

Numerical simulation of cloud droplet formation in a tank  

Science Conference Proceedings (OSTI)

Using the computational fluid dynamics (CFD) code FLUENT 6 together with the fine particle model (FPM), numerical simulations of droplet dynamics in a 12.4m^3 cloud tank were conducted. The coupled fields of water vapor, temperature, flow velocity, particle ... Keywords: Cloud droplet formation, Particle-dynamics modeling, Stirred tank, Turbulence

Matthias Schtze; Frank Stratmann

2008-09-01T23:59:59.000Z

126

Numerical simulation of the electron beam welding process  

Science Conference Proceedings (OSTI)

Electron beam welding is a highly efficient and precise welding method that is being increasingly used in industrial manufacturing and is of growing importance in industry. Compared to other welding processes it offers the advantage of very low heat ... Keywords: 3D conical heat source, Electron beam welding (EBW), Heat-affected zone, Numerical simulation, Thermomechanical coupling analysis

Piotr Lacki; Konrad Adamus

2011-06-01T23:59:59.000Z

127

Numerical Simulations of an Observed Narrow Cold-Frontal Rainband  

Science Conference Proceedings (OSTI)

A cold-frontal rainband, which occurred during the afternoon of 28 December 1988, is numerically simulated using the Penn StateNCAR three-dimensional MM5 modeling system. This case is characterized by a line of severe convection that has a ...

Chaing Chen; Craig H. Bishop; George S. Lai; Wei-Kuo Tao

1997-06-01T23:59:59.000Z

128

Numerical Simulation of Airmass Transformation over the Gulf of Mexico  

Science Conference Proceedings (OSTI)

A mesoscale numerical simulation (35 km) of a return-flow event over the Gulf of Mexico that occurred during the Gulf of Mexico Experiment (GUFMEX) is presented in order to examine the structure and the transformation of the polar air mass and to ...

Jocelyn Mailhot

1992-08-01T23:59:59.000Z

129

Numerical Simulation Research on Proppant Transport in Hydraulic Fracture  

Science Conference Proceedings (OSTI)

Among the mathematical models of describing the prop pant settling or transport process, the particle settling velocity primarily takes the gravity, buoyancy and other conventional forces into consideration under the equilibrium condition of forces, ... Keywords: hydraulic fracturing, solid-liquid two phaes flow, proppant transport, numerical simulation, predictor-corrector method

Yongming Li; Song Wang; Jinzhou Zhao; Zhang Jiyao; Xiangzeng Wang; Ruimin Gao

2011-10-01T23:59:59.000Z

130

Scaling Theory and Numerical Simulations of Aerogel Sintering  

E-Print Network (OSTI)

A simple scaling theory for the sintering of fractal aerogels is presented. The densification at small scales is described by an increase of the lower cut-off length a accompanied by a decrease of the upper cut-off length ?, in order to conserve the total mass of the system. Scaling laws are derived which predict how a, ? and the specific pore surface area ? should depend on the density ?. Following the general ideas of the theory, numerical simulations of sintering are proposed starting from computer simulations of aerogel structure based on a diffusion-limited cluster-cluster aggregation gelling process. The numerical results for a, ? and ? as a function of ? are discussed according to the initial aerogel density. The scaling theory is only fully recovered in the limit of very low density where the original values of a and ? are well separated. These numerical results are compared with experiments on partially densified aerogels.

Rmi Jullien; Nathalie Olivi-tran; Anwar Hasmy; Thierry Woignier; Daniel Bourret; Robert Sempr

2008-01-01T23:59:59.000Z

131

Numerical and experimental investigations on vibration of simulated CANDU fuel bundles subjected to turbulent fluid flow.  

E-Print Network (OSTI)

??Vibration of simulated CANDU fuel bundles induced by coolant flow is investigated in this thesis through experiments and numerical simulations. Two simulated bundles and a (more)

Zhang, Xuan

2011-01-01T23:59:59.000Z

132

Numerical simulation of micro-fluidic passive and active mixers  

E-Print Network (OSTI)

Numerical simulations of mixing using passive and active techniques are performed. For passive mixing, numerical modeling of a micro-fluidic device, build by Holden and Cremer, was performed. The micro-fluidic device consists of a Y-junction that allows inflow of two different species of fluid into a main-channel. The main-channel eventually splits into eleven smaller output micro-channels. This device enables control of molecular diffusion from one fluid stream into the other by regulating the flow rate. Hence, output channels exhibit predetermined concentration values, which allow concentration dependent chemistry experiments in each output channel. Convective diffusive transport in this micro mixer is studied numerically and theoretically. Our model prediction are compared with the experimental data. Numerical simulations of a peristaltically driven micro mixer is studied as a function of the travelling wave amplitude and the Reynolds number. First the numerical scheme was verified for small deformation cases for moderate and large Reynolds numbers. Kinematics of large deformation conditions are studied for various Reynolds numbers.

Kumar, Saurabh

2002-01-01T23:59:59.000Z

133

Thermal numerical simulator for laboratory evaluation of steamflood oil recovery  

Science Conference Proceedings (OSTI)

A thermal numerical simulator running on an IBM AT compatible personal computer is described. The simulator was designed to assist laboratory design and evaluation of steamflood oil recovery. An overview of the historical evolution of numerical thermal simulation, NIPER's approach to solving these problems with a desk top computer, the derivation of equations and a description of approaches used to solve these equations, and verification of the simulator using published data sets and sensitivity analysis are presented. The developed model is a three-phase, two-dimensional multicomponent simulator capable of being run in one or two dimensions. Mass transfer among the phases and components is dictated by pressure- and temperature-dependent vapor-liquid equilibria. Gravity and capillary pressure phenomena were included. Energy is transferred by conduction, convection, vaporization and condensation. The model employs a block centered grid system with a five-point discretization scheme. Both areal and vertical cross-sectional simulations are possible. A sequential solution technique is employed to solve the finite difference equations. The study clearly indicated the importance of heat loss, injected steam quality, and injection rate to the process. Dependence of overall recovery on oil volatility and viscosity is emphasized. The process is very sensitive to relative permeability values. Time-step sensitivity runs indicted that the current version is time-step sensitive and exhibits conditional stability. 75 refs., 19 figs., 19 tabs.

Sarathi, P.

1991-04-01T23:59:59.000Z

134

22nd International Conference on Numerical Simulation of Plasmas (ICNSP) |  

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

September 7, 2011, 9:00am to September 11, 2011, 5:00pm September 7, 2011, 9:00am to September 11, 2011, 5:00pm Conference Long Branch, NJ 22nd International Conference on Numerical Simulation of Plasmas (ICNSP) The purpose of this conference series, which started at the College of William and Mary in 1967 "to disseminate progress in the state-of-the-art of plasma simulation and to report specific applications of computer experiments to various areas of plasma physics," remains unchanged. On the other hand, the topics of the Conference, which has been expanded over the years, now include: Topics: Magnetic & Inertial Fusion Plasmas Space & Astrophysical Plasmas High Intensity Beams & Laser Plasma Interactions Low-temperature Plasmas Numerical Methods & High Performance Computing Scientific Visualization

135

Petascale Direct Numerical Simulations of Turbulent Channel Flow  

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

Petascale Petascale Direct Numerical Simulations of Turbulent Channel Flow MyoungKyu Lee mk@ices.utexas.edu Department of Mechanical Engineering University of Texas at Austin ESP Meeting May, 2013 M.K. Lee (Univ of Texas, Austin) Petascale DNS of Turbulent Channel Flow ESP Meeting May, 2013 1 / 30 Contents Project Overview Performance Optimization Early Result Conclusion M.K. Lee (Univ of Texas, Austin) Petascale DNS of Turbulent Channel Flow ESP Meeting May, 2013 2 / 30 Project Overview Project Title ◮ Petascale Direct Numerical Simulations of Turbulent Channel Flow Goal ◮ Expanding our understand of wall-bounded turbulence Personnel ◮ P.I. : Robert Moser ◮ Primary Developer : M.K.Lee ◮ Software Engineering Support : Nicholas Malaya ◮ Catalyst : Ramesh Balakrishnan M.K. Lee (Univ of Texas, Austin) Petascale DNS of Turbulent Channel Flow ESP Meeting May, 2013 3 / 30 Turbulent

136

Numerical simulations of the decay of primordial magnetic turbulence  

SciTech Connect

We perform direct numerical simulations of forced and freely decaying 3D magnetohydrodynamic turbulence in order to model magnetic field evolution during cosmological phase transitions in the early Universe. Our approach assumes the existence of a magnetic field generated either by a process during inflation or shortly thereafter, or by bubble collisions during a phase transition. We show that the final configuration of the magnetic field depends on the initial conditions, while the velocity field is nearly independent of initial conditions.

Kahniashvili, Tina [McWilliams Center for Cosmology and Department of Physics, Carnegie Mellon University, 5000 Forbes Ave, Pittsburgh, Pennsylvania 15213 (United States); Department of Physics, Laurentian University, Ramsey Lake Road, Sudbury, ON P3E 2C (Canada); Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Brandenburg, Axel [Nordita, AlbaNova University Center, Roslagstullsbacken 23, 10691 Stockholm (Sweden); Department of Astronomy, Stockholm University, SE 10691 Stockholm (Sweden); Tevzadze, Alexander G. [Abastumani Astrophysical Observatory, Ilia State University, 2A Kazbegi Ave, Tbilisi, GE-0160 (Georgia); Faculty of Exact and Natural Sciences, Tbilisi State University, 1 Chavchavadze Avenue Tbilisi, GE-0128 (Georgia); Ratra, Bharat [Department of Physics, Kansas State University, 116 Cardwell Hall, Manhattan, Kansas 66506 (United States)

2010-06-15T23:59:59.000Z

137

Cloud Statistics in Numerical Simulations of the ISM  

E-Print Network (OSTI)

We present preliminary results on the energy budgets of clouds in two-dimensional numerical simulations of the interstellar medium. Using an automated cloud-identification algorithm, we calculate the gravitational, internal, kinetic and magnetic energies of the clouds. We find that, within a dispersion of roughly one order of magnitude, the gravitational energy in the clouds is balanced by the remaining energies. Furthermore, within the same dispersion, there appears to be equipartition between the kinetic and magnetic energies.

J. Ballesteros-Paredes; E. Vazquez-Semadeni

1996-02-01T23:59:59.000Z

138

Numerical Simulation Study on Transpired Solar Air Collector  

E-Print Network (OSTI)

The unglazed transpired solar air collector is now a well-recognized solar air heater for heating outside air directly. In this article, researchers introduced numerical simulation tools into the solar air collector research area, analyzed the performance characteristics of the unglazed transpired solar air collector and compared them with several kinds of traditional solar air collectors. The results showed that the unglazed transpired solar air collector has unparalleled advantages in the ventilation preheating area and also proves that CFD tools have their own advantages in the solar air collector research area.

Wang, C.; Guan, Z.; Zhao, X.; Wang, D.

2006-01-01T23:59:59.000Z

139

A numerical model simulation of longshore transport for Galveston Island  

E-Print Network (OSTI)

The shoreline changes, deposition patterns, and longshore transport rates were calculated for the coast of Galveston Island using a numerical model simulation. The model only simulated changes due to waves creating longshore currents. East Beach showed a net accretion pattern, with erosion confined to the eastern section of the area. Large accretion was found near the first groin indicating transport from east to west. The groin field fluctuated with erosion and accretion, with a net gain of shoreline. The unprotected beach in front of the seawall eroded almost completely away. West Beach had a net loss of shoreline overall. This was largely due to the shoreline erosion found at San Luis Pass. The majority of West Beach was frequently unstable, fluctuating between erosion and accretion.

Gilbreath, Stephen Alexander

1995-01-01T23:59:59.000Z

140

The Influence of Airborne Doppler Radar Data Quality on Numerical Simulations of a Tropical Cyclone  

Science Conference Proceedings (OSTI)

The impact of airborne Doppler radar data assimilation on improving numerical simulations of tropical cyclones (TCs) has been well recognized. However, the influence of radar data quality on the numerical simulation of tropical cyclones has not ...

Lei Zhang; Zhaoxia Pu; Wen-Chau Lee; Qingyun Zhao

2012-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

VNIIEF VNIIEF Methods of Numerical Simulation for Multi-  

National Nuclear Security Administration (NNSA)

32 32 VNIIEF VNIIEF Methods of Numerical Simulation for Multi- Methods of Numerical Simulation for Multi- Dimensional Gas Dynamic Flows Dimensional Gas Dynamic Flows Spir Spiri idonov donov V.F V.F., ., Bakhrakh Bakhrakh S.M., S.M., Velichko Velichko S.V., S.V., Delov Delov V.I., V.I., Yanilkin Yu.V Yanilkin Yu.V., ., Sokolov Sokolov S.S., S.S., Butnev Butnev O.I, O.I, Stenin Stenin A.M., A.M., Zmushko Zmushko V.V., V.V., Voronin Voronin B.L., B.L., Bykov Bykov A.N. A.N. RFCN-VNIIEF, 607190, RFCN-VNIIEF, 607190, Sarov Sarov, , Nizhni Nizhni Novgorod region Novgorod region Joint Russian-American Five-Laboratory Conference on Computation Joint Russian-American Five-Laboratory Conference on Computation Mathematics|Physics Mathematics|Physics 19-23 June 2005, 19-23 June 2005, Crowne

142

Accurate Numerical Simulations Of Chemical Phenomena Involved in Energy  

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

Visualization of the spin density from the excess electron cluster. Robert Visualization of the spin density from the excess electron cluster. Robert Harrison Accurate Numerical Simulations Of Chemical Phenomena Involved in Energy Production and Storage with MADNESS and MPQC PI Name: Robert Harrison PI Email: harrisonrj@ornl.gov Institution: ORNL Allocation Program: ESP Allocation Hours at ALCF: 150 Million Year: 2010 to 2013 Research Domain: Chemistry Researchers propose to focus on the problems of catalysis and heavy element chemistry for fuel reprocessing-both of which are of immediate interest to the Department of Energy (DOE), are representative of a very broad class of problems in chemistry, and demand the enormous computational resources anticipated from the next generation of leadership computing facilities. Also common to both is the need for accurate electronic structure

143

Numerical simulation and immersive visualization of hairpin vortices.  

SciTech Connect

To better understand the vortex dynamics of coherent structures in turbulent and transitional boundary layers, we consider direct numerical simulation of the interaction between a flat-plate-boundary-layer flow and an isolated hemispherical roughness element. Of principal interest is the evolution of hairpin vortices that form an interlacing pattern in the wake of the hemisphere, lift away from the wall, and are stretched by the shearing action of the boundary layer. Using animations of unsteady three-dimensional representations of this flow, produced by the vtk toolkit and enhanced to operate in a CAVE virtual environment, we identify and study several key features in the evolution of this complex vortex topology not previously observed in other visualization formats.

Tufo, H.M.; Fischer, P.F.; Papka, M.E.; Blom, K.

1999-08-28T23:59:59.000Z

144

Numerical simulation of linear fiction welding (LFW) processes  

Science Conference Proceedings (OSTI)

Solid state welding processes are becoming increasingly important due to a large number of advantages related to joining ''unweldable'' materials and in particular light weight alloys. Linear friction welding (LFW) has been used successfully to bond non-axisymmetric components of a range of materials including titanium alloys, steels, aluminum alloys, nickel, copper, and also dissimilar material combinations. The technique is useful in the research of quality of the joints and in reducing costs of components and parts of the aeronautic and automotive industries.LFW involves parts to be welded through the relative reciprocating motion of two components under an axial force. In such process the heat source is given by the frictional forces work decaying into heat determining a local softening of the material and proper bonding conditions due to both the temperature increase and the local pressure of the two edges to be welded. This paper is a comparative test between the numerical model in two dimensions, i.e. in plane strain conditions, and in three dimensions of a LFW process of AISI1045 steel specimens. It must be observed that the 3D model assures a faithful simulation of the actual threedimensional material flow, even if the two-dimensional simulation computational times are very short, a few hours instead of several ones as the 3D model. The obtained results were compared with experimental values found out in the scientific literature.

Fratini, L.; La Spisa, D. [University of Palermo-Dept. of Industrial engineering (Italy)

2011-05-04T23:59:59.000Z

145

A robust, colocated, implicit algorithm for direct numerical simulation of compressible, turbulent flows  

Science Conference Proceedings (OSTI)

A non-dissipative, robust, implicit algorithm is proposed for direct numerical and large-eddy simulation of compressible turbulent flows. The algorithm addresses the problems caused by low Mach numbers and under-resolved high Reynolds numbers. It colocates ... Keywords: All-Mach number, Compressible turbulence, Direct numerical simulation, Discrete energy conservation, Large-eddy simulation, Non-dissipative

Yucheng Hou; Krishnan Mahesh

2005-05-01T23:59:59.000Z

146

Numerical Simulation of the Interaction between the Dryline and Horizontal Convective Rolls  

Science Conference Proceedings (OSTI)

The results of high-resolution simulations of an idealized dryline environment are discussed. The use of a single high-resolution domain, combined with accurate advection numerics and minimized numerical filtering, allows the explicit resolution ...

Steven E. Peckham; Robert B. Wilhelmson; Louis J. Wicker; Conrad L. Ziegler

2004-07-01T23:59:59.000Z

147

Numerical study of error propagation in Monte Carlo depletion simulations  

Science Conference Proceedings (OSTI)

Improving computer technology and the desire to more accurately model the heterogeneity of the nuclear reactor environment have made the use of Monte Carlo depletion codes more attractive in recent years, and feasible (if not practical) even for 3-D depletion simulation. However, in this case statistical uncertainty is combined with error propagating through the calculation from previous steps. In an effort to understand this error propagation, a numerical study was undertaken to model and track individual fuel pins in four 17 x 17 PWR fuel assemblies. By changing the code's initial random number seed, the data produced by a series of 19 replica runs was used to investigate the true and apparent variance in k{sub eff}, pin powers, and number densities of several isotopes. While this study does not intend to develop a predictive model for error propagation, it is hoped that its results can help to identify some common regularities in the behavior of uncertainty in several key parameters. (authors)

Wyant, T.; Petrovic, B. [Nuclear and Radiological Engineering, Georgia Inst. of Technology, 770 State Street, Atlanta, GA 30332-0745 (United States)

2012-07-01T23:59:59.000Z

148

Idealized Numerical Simulations of the Interactions between Buoyant Plumes and Density Currents  

Science Conference Proceedings (OSTI)

Idealized numerical experiments using a large-eddy simulation (LES) model are performed to examine the fundamental dynamical processes associated with the interactions between buoyant plumes and density currents. The aim of these simulations is ...

Philip Cunningham

2007-06-01T23:59:59.000Z

149

Three-Dimensional Numerical Simulations of Strongly Stratified Flow past Conical Orography  

Science Conference Proceedings (OSTI)

Results from a series of numerical simulations of three-dimensional stably stratified flows past conical orography with unit slope are presented and are compared directly with laboratory results from a stratified towing tank. The simulations are ...

S. B. Vosper

2000-11-01T23:59:59.000Z

150

Comparison of Ice-Phase Microphysical Parameterization Schemes Using Numerical Simulations of Tropical Convection  

Science Conference Proceedings (OSTI)

A numerical cloud model is used to evaluate the performance of several ice parameterizations. Results from simulations using these schemes are contrasted with each other, with an ice-free control simulation, and with observations to determine to ...

Michale McCumber; Wei-Kuo Tao; Joanne Simpson; Richard Penc; Su-Tzai Soong

1991-07-01T23:59:59.000Z

151

Direct Numerical Simulation of Differential Scalar Diffusion in Three-Dimensional Stratified Turbulence  

Science Conference Proceedings (OSTI)

The potential for differential turbulent transport of oceanic temperature (T) and salinity () is explored using three-dimensional direct numerical simulations of decaying stratified turbulence. The simulations employ a realistic molecular ...

Ann E. Gargett; William J. Merryfield; Greg Holloway

2003-08-01T23:59:59.000Z

152

Direct Numerical Simulation of Differential Scalar Diffusion in Three-Dimensional Stratified Turbulence  

Science Conference Proceedings (OSTI)

The potential for differential turbulent transport of oceanic temperature (T) and salinity (S) is explored using three-dimensional direct numerical simulations of decaying stratified turbulence. The simulations employ a realistic molecular ...

Ann E. Gargett; William J. Merryfield; Greg Holloway

2003-08-01T23:59:59.000Z

153

Alpha migration through air filters: A numerical simulation  

Science Conference Proceedings (OSTI)

This theoretical study investigates the migration of alpha-emitting particles through high-efficiency particulate air (HEPA) filters. As part of the study, a review of previous research relating to the alpha-migration phenomena was conducted. As a result of the literature review, a numerical model was developed to simulate the migration of alpha-emitting radionuclide aerosols through HEPA filters. This model predicts the filter performance with regard to particle penetration. It can be used to better estimate the penetration of alpha radioactive species through filter systems for environmental concerns, to aid in the use of current filter systems, and to design new filter systems. It is obvious from the review of the literature that evidence exists of migration of alpha radionuclide species through high-efficiency filter media. The theories suggest that nanometer-size particles can eventually penetrate fibrous filters because of gradual movement through the filter matrix. It is conjectured that this movement may be induced by energies caused by the alpha recoil from the decay process by thermal energies. It is further hypothesized that such nanometer-size particles, containing radionuclide species can be formed from larger particles already captured within the filter. The penetration of such small particles through high-efficiency filter media is so low that experimental corroboration of these mechanisms by penetration measurements is difficult at best. A number of items were identified that affect the migration of alpha-emitting particles through a filter. These include the size distribution of aerosol particles entering the filter, the size distribution of fragment particles produced by alpha recoil, the penetration of the challenge aerosols and fragment particles, the velocity through the filter, the radionuclide specific activity, the alpha recoil energy, and the surface-binding energies between the particle and the filter matrix.

Biermann, A.H.; da Roza, R.A.; Chang, Yun.

1991-12-11T23:59:59.000Z

154

Numerical Simulation and Experimental Analysis of Notched Failure ...  

Science Conference Proceedings (OSTI)

Recent advances in numerical methods, such as extended and augmented finite element modelling (X-FEM and A-FEM respectively) provide significant...

155

On the Numerical Simulation of Waterflooding of Heterogeneous Petroleum Reservoirs  

E-Print Network (OSTI)

We present a new, naturally parallelizable, accurate numerical method for the solution of transport-dominated diffusion processes in heterogeneous porous media.

Jim Douglas, Jr.; Frederico Furtado; Felipe Pereira

1997-01-01T23:59:59.000Z

156

Development of a carburizing and quenching simulation tool: Numerical simulations of rings and gears  

DOE Green Energy (OSTI)

This paper describes a calculational procedure using the ABAQUS finite element code that simulates a carburizing and quench heat treat cycle for automotive gears. The procedure features a numerically efficient 2-phase constitutive model to represent transformational plasticity effects for the austenite/martensite transformation together with refined finite element meshes to capture the steep gradients in stress and composition near the gear surfaces. The procedure is illustrated on carburizing and quenching of a thick ring, and comparison of model predictions for distortion, phase distribution, and residual stress with experiment is discussed. Sensitivity of predictions to mesh refinement is studied.

Anderson, C.; Goldman, P.; Rangaswamy, P. [Los Alamos National Lab., NM (United States)] [and others

1996-06-24T23:59:59.000Z

157

Stochastic algorithms for the analysis of numerical flame simulations  

Science Conference Proceedings (OSTI)

Recent progress in simulation methodologies and high-performance parallel computers have made it is possible to perform detailed simulations of multidimensional reacting flow phenomena using comprehensive kinetics mechanisms. As simulations become larger ... Keywords: computational diagnostics, particle tracking, reacting flows, stochastic

J. B. Bell; M. S. Day; J. F. Grcar; M. J. Lijewski

2005-01-01T23:59:59.000Z

158

Adaptive higher order numerical simulation of heat and mass transfer in fluidized beds  

E-Print Network (OSTI)

Adaptive higher order numerical simulation of heat and mass transfer in fluidized beds Ch. Nagaiah1 adaptive numerical results of heat and mass transfer in fluidized beds using higher order time stepping injection. The numerical results are tested with different time stepping methods for different spatial grid

Magdeburg, Universität

159

Coupling geological and numerical models to simulate groundwater flow and contaminant transport in fractured media  

Science Conference Proceedings (OSTI)

A new modeling approach is presented to improve numerical simulations of groundwater flow and contaminant transport in fractured geological media. The approach couples geological and numerical models through an intermediate mesh generation phase. As ... Keywords: Fractures, Geomodel, Influence coefficient technique, Numerical modeling, Tetrahedra

Daniela Blessent; Ren Therrien; Kerry MacQuarrie

2009-09-01T23:59:59.000Z

160

A Benchmark Simulation for Moist Nonhydrostatic Numerical Models  

Science Conference Proceedings (OSTI)

A benchmark solution that facilitates testing the accuracy, efficiency, and efficacy of moist nonhydrostatic numerical model formulations and assumptions is presented. The solution is created from a special configuration of moist model processes ...

George H. Bryan; J. Michael Fritsch

2002-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Numerical Simulations of Shelterbelt Effects on Wind Direction  

Science Conference Proceedings (OSTI)

A neutral boundary layer nonhydrostatic numerical model is used to determine the characteristics of shelterbelt effects on mean wind direction and to study the processing causing wind rotation when air passes through a shelterbelt. The model uses ...

Hao Wang; Eugene S. Takle

1995-10-01T23:59:59.000Z

162

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

163

Numerical Simulations of the Formation of Hurricane Gabrielle (2001)  

Science Conference Proceedings (OSTI)

This study examines the formation of Hurricane Gabrielle (2001), focusing on whether an initial disturbance and vertical wind shear were favorable for development. This examination is performed by running numerical experiments using the fifth-...

K. D. Musgrave; C. A. Davis; M. T. Montgomery

2008-08-01T23:59:59.000Z

164

Numerical Simulation of Internal Kelvin Waves and Coastal Upwelling Fronts  

Science Conference Proceedings (OSTI)

Two three-dimensional primitive equation numerical ocean models are applied to the problem of internal Kelvin waves and coastal upwelling in the Great Lakes. One is the Princeton Ocean Model (POM) with a terrain-following (sigma) vertical ...

Dmitry Beletsky; William P. OConnor; David J. Schwab; David E. Dietrich

1997-07-01T23:59:59.000Z

165

Dynamical Subgrid-Scale Parameterizations from Direct Numerical Simulations  

Science Conference Proceedings (OSTI)

Dynamical subgrid-scale parameterizations of stochastic backscatter, eddy drain viscosity, and net eddy viscosity have been formulated and calculated for two-dimensional turbulent flows on the sphere based on the statistics of direct numerical ...

Jorgen S. Frederiksen; Steven M. Kepert

2006-11-01T23:59:59.000Z

166

The Interaction of Numerically Simulated Supercells Initiated along Lines  

Science Conference Proceedings (OSTI)

Supercells in the southern plains are often localized, forming as cells along a convective line, even though the environment may support supercell formation over a much broader, mesoscale region. A set of numerical experiments is devised in which ...

Howard B. Bluestein; Morris L. Weisman

2000-09-01T23:59:59.000Z

167

Birth of the Universe, Direct Numerical Simulations of Cosmological...  

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

Simulations of Cosmological Reionization November 30, 2011 Tweet EmailPrint In this video from SC11, Michael Norman (SDSC), Joseph Insley (MCS), and Rick Wagner (SDSC) describe...

168

Numerical Simulation of Liquid Metal Flows under the Influence of ...  

Science Conference Proceedings (OSTI)

A Coupled CFD-Thermodynamic-Kinetic Model to Simulate a Gas Stirred Ladle ... Exercise on Thermal and Thermosolutal Natural Convection in Liquid Alloys.

169

Elements of the Microphysical Structure of Numerically Simulated Nonprecipitating Stratocumulus  

Science Conference Proceedings (OSTI)

A set of 500 simulated trajectories and a simple parcel model are used to (i) evaluate the performance of a large eddy simulation model coupled to a detailed representation of the droplet spectrum (the LES-BM model) and (ii) gain insight into the ...

Bjorn Stevens; Graham Feingold; William R. Cotton; Robert L. Walko

1996-04-01T23:59:59.000Z

170

Numerical Simulation of Endoscopic Images in Photodynamic Diagnosis  

Science Conference Proceedings (OSTI)

This paper introduces a photon subsurface scattering method to simulate light transport in human colon tissue. First the theoretical model and parameters of human tissue including autofluorescence phenomenon was presented. Then it was described the Monte-Carlo ... Keywords: autofluorescence simulation, photodynamic diagnosis, photon mapping, subsurface scattering

Andrzej Zacher

2008-11-01T23:59:59.000Z

171

On the elimination of numerical Cerenkov radiation in PIC simulations  

Science Conference Proceedings (OSTI)

Particle-in-cell (PIC) simulations are a useful tool in modeling plasma in physical devices. The Yee finite difference time domain (FDTD) method is commonly used in PIC simulations to model the electromagnetic fields. However, in the Yee FDTD method, ...

Andrew D. Greenwood; Keith L. Cartwright; John W. Luginsland; Ernest A. Baca

2004-12-01T23:59:59.000Z

172

Structure and Evolution of Numerically Simulated Squall Lines  

Science Conference Proceedings (OSTI)

Using a three-dimensional numerical cloud model, we investigate the effects of vertical wind shear on squall-line structure and evolution over a wide range of shear magnitudes, depths, and orientations relative to the line. We find that the ...

Morris L. Weisman; Joseph B. Klemp; Richard Rotunno

1988-07-01T23:59:59.000Z

173

Numerical Simulation of Drainage Flow in Brush Creek, Colorado  

Science Conference Proceedings (OSTI)

One of the objectives of the Atmospheric Studies in Complex Terrain (ASCOT) program is to develop numerical models that can be used to aid in the understanding and prediction of flow patterns observed over complex terrain. As part of this program,...

John M. Leone Jr.; Robert L. Lee

1989-06-01T23:59:59.000Z

174

Sensitivity Studies on the Continentality of a Numerically Simulated Cumulonimbus  

Science Conference Proceedings (OSTI)

The cloud model of Tripoli and Cotton was used to simulate a cumulonimbus cloud observed during the Cooperative Convective Precipitation Experiment (CCOPE). We tested the sensitivity of the precipitation pathways in the model to the initial ...

R. Banta; K. R. Hanson

1987-02-01T23:59:59.000Z

175

Discrete Propagation in Numerically Simulated Nocturnal Squall Lines  

Science Conference Proceedings (OSTI)

Simulations of a typical midlatitude squall line were used to investigate a mechanism for discrete propagation, defined as convective initiation ahead of an existing squall line leading to a faster propagation speed for the storm complex. Radar ...

Robert G. Fovell; Gretchen L. Mullendore; Seung-Hee Kim

2006-12-01T23:59:59.000Z

176

NREL Developing Numerical Simulation Tool to Study Hydrokinetic...  

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

M.; Li, Y.; Moriarty, P. (2012). "A Large-Eddy Simulation Study of Wake Propagation and Power Production in an Array of Tidal-Current Turbines." Accepted by Proceedings of the...

177

Numerical Simulations of Sea-Breeze Circulations over Northwest Hawaii  

Science Conference Proceedings (OSTI)

Sea-breeze cases during 2328 June 1978 over northwest Hawaii are simulated using the National Centers for Environmental Prediction (NCEP) Mesoscale Spectral Model (MSM) coupled with an advanced Land Surface Model (LSM) with 3-km horizontal ...

Yongxin Zhang; Yi-Leng Chen; Thomas A. Schroeder; Kevin Kodama

2005-12-01T23:59:59.000Z

178

Numerical simulation of low Mach number reacting flows  

Science Conference Proceedings (OSTI)

Using examples from active research areas in combustion andastrophysics, we demonstrate a computationally efficient numericalapproach for simulating multiscale low Mach number reacting flows. Themethod enables simulations that incorporate an unprecedented range oftemporal and spatial scales, while at the same time, allows an extremelyhigh degree of reaction fidelity. Sample applications demonstrate theefficiency of the approach with respect to a traditional time-explicitintegration method, and the utility of the methodology for studying theinteraction of turbulence with terrestrial and astrophysical flamestructures.

Bell, John B.; Aspden, Andrew J.; Day, Marcus S.; Lijewski,Michael J.

2007-06-20T23:59:59.000Z

179

Detailed Numerical Simulation of the Graniteville Train Collision  

SciTech Connect

An unfortunate accident occurred in Graniteville, South Carolina on 6 January, 2005 when a train carrying a variety of hazardous chemicals collided with a stationary train parked on a siding rail (spur). The Savannah River National Laboratory (SRNL) runs prognostic atmospheric simulations of the Central Savannah River Area (CSRA) on an operational basis in the event of such airborne releases. Although forecast information was provided at 2-km horizontal grid spacing during the accident response, a higher-resolution simulation was later performed to examine influences of local topography on plume migration. The Regional Atmospheric Modeling System (RAMS, version 4.3.0) was used to simulate meteorology using multiple grids with an innermost grid spacing of 125 meters. This report discusses comparisons of simulated meteorology with local observations and applications using two separate transport models. Results from the simulations are shown to generally agree with meteorological observations at the time. Use of a dense gas model to simulate localized effects indicates agreement with fatalities in the immediate area and visible damage to vegetation.

Buckley, R. L.

2005-10-24T23:59:59.000Z

180

Numerical simulation of the hydrodynamical combustion to strange quark matter  

Science Conference Proceedings (OSTI)

We present results from a numerical solution to the burning of neutron matter inside a cold neutron star into stable u,d,s quark matter. Our method solves hydrodynamical flow equations in one dimension with neutrino emission from weak equilibrating reactions, and strange quark diffusion across the burning front. We also include entropy change from heat released in forming the stable quark phase. Our numerical results suggest burning front laminar speeds of 0.002-0.04 times the speed of light, much faster than previous estimates derived using only a reactive-diffusive description. Analytic solutions to hydrodynamical jump conditions with a temperature-dependent equation of state agree very well with our numerical findings for fluid velocities. The most important effect of neutrino cooling is that the conversion front stalls at lower density (below {approx_equal}2 times saturation density). In a two-dimensional setting, such rapid speeds and neutrino cooling may allow for a flame wrinkle instability to develop, possibly leading to detonation.

Niebergal, Brian; Ouyed, Rachid [Department of Physics and Astronomy, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4 (Canada); Jaikumar, Prashanth [Department of Physics and Astronomy, California State University Long Beach, 1250 Bellflower Blvd., Long Beach, California 90840 (United States); Institute of Mathematical Sciences, C.I.T. Campus, Chennai, TN 600113 (India)

2010-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Numerical simulation of copper ablation by ultrashort laser pulses  

E-Print Network (OSTI)

Using a modified self-consistent one-dimensional hydrodynamic lagrangian fluid code, laser ablation of solid copper by ultrashort laser pulses in vacuum was simulated to study fundamental mechanisms and to provide a guide for drilling periodic microholes or microgratings on the metal surface. The simulated laser ablation threshold is a approximate constancy in femtosecond regime and increases as the square root of pulse duration in picosecond regime. The ablation depth as a function of pulse duration shows four different regimes and a minimum for a pulse duration of ~ 12ps for various laser fluences. The influence of laser-induced plasma shielding on ablation depth is also studied.

Ding, PengJi; Li, YuHong

2011-01-01T23:59:59.000Z

182

Numerical Simulation on Forced Swirl Combustion Chamber in Diesel Engine  

Science Conference Proceedings (OSTI)

A concept of forced swirl combustion chamber in diesel engine is proposed in this paper. It can be used to enhance the intensity of swirl flow in the cylinder and accelerate the rate of air-fuel mixture process by designing the special structure in the ... Keywords: diesel engine, forced swirl, combustion chamber, simulation

Yong Shang; Fu-shui Liu; Xiang-rong Li

2010-12-01T23:59:59.000Z

183

Numerical Simulation on Forced Swirl Combustion Chamber in Diesel Engine  

Science Conference Proceedings (OSTI)

A concept of forced swirl combustion chamber in diesel engine is proposed in this paper. It can be used to enhance the intensity of swirl flow in the cylinder and accelerate the rate of air-fuel mixture process by designing the special structure in the ... Keywords: diesel engine, forced swirl, combustion chamber, simulation

Shang Yong; Liu Fu-shui; Li Xiang-rong

2011-02-01T23:59:59.000Z

184

Numerical Simulation of Katabatic Flow with Changing Slope Angle  

Science Conference Proceedings (OSTI)

A large eddy simulation (LES) model and the Advanced Regional Prediction System (ARPS) model, which does not resolve turbulent eddies, are used to study the effect of a slope angle decrease on the structure of katabatic slope flows. For a simple, ...

Craig M. Smith; Eric D. Skyllingstad

2005-11-01T23:59:59.000Z

185

Numerical Simulation of Boundary Layer Variables Using ??? Closure Scheme  

Science Conference Proceedings (OSTI)

In this study, a one-and-a-half-order ??? closure scheme is used to study the planetary boundary layer development over a full diurnal cycle using Wangara 33d-day observations as initial conditions. The simulated results are compared with a first-...

N. Ramanathan; K. Srinivasan; B. V. Seshasayee

1995-02-01T23:59:59.000Z

186

Numerical Simulation of Ice-Phase Convective Cloud Seeding  

Science Conference Proceedings (OSTI)

A two-dimensional time-dependent cloud model which covers a region 19.2 km 19.2 km in the x and z directions with 200 m grid intervals, has been used to simulate silver iodide (AgI) seeding effects on strong convective clouds. The model is a ...

Eirh-Yu Hsie; Richard D. Farley; Harold D. Orville

1980-08-01T23:59:59.000Z

187

Numerical Simulation of CloudClear Air Interfacial Mixing: Homogeneous versus Inhomogeneous Mixing  

Science Conference Proceedings (OSTI)

This note presents an analysis of several dozens of direct numerical simulations of the cloudclear air mixing in a setup of decaying moist turbulence with bin microphysics. The goal is to assess the instantaneous relationship between the ...

Miroslaw Andrejczuk; Wojciech W. Grabowski; Szymon P. Malinowski; Piotr K. Smolarkiewicz

2009-08-01T23:59:59.000Z

188

Numerical Simulations of Radiative Cooling beneath the Anvils of Supercell Thunderstorms  

Science Conference Proceedings (OSTI)

Numerical simulations of supercell thunderstorms that include parameterized radiative transfer and surface fluxes are performed using the Advanced Regional Prediction System (ARPS) to investigate the effects of anvil shadows on the near-storm ...

Jeffrey Frame; Paul Markowski

2010-08-01T23:59:59.000Z

189

A Numerical Simulation Study of the Effects of Anvil Shading on Quasi-Linear Convective Systems  

Science Conference Proceedings (OSTI)

Numerical simulations are used to investigate how the attenuation of solar radiation by the intervening cumulonimbus cloud, particularly its large anvil, affects the structure, intensity, and evolution of quasi-linear convective systems and the ...

Andrew J. Oberthaler; Paul M. Markowski

2013-03-01T23:59:59.000Z

190

Numerical Simulation of Topographically Forced Mesoscale Variability in a Well-Mixed Marine Layer  

Science Conference Proceedings (OSTI)

A simple nonlinear numerical model of a well-mixed marine layer is used to study topographically forced mesoscale variability off coastal California. The model is used to simulate a persistent wind maximum observed near Point Conception during ...

Lee W. Eddington; J. J. O'brien; D. W. Stuart

1992-12-01T23:59:59.000Z

191

A Transfer Function Analysis of Numerical Schemes Used to Simulate Geostrophic Adjustment  

Science Conference Proceedings (OSTI)

Traditional analysis of finite-difference and finite-element schemes used in numerical weather prediction has concentrated almost exclusively on an analysis of the accuracy with which the scheme simulates the phase speeds involved. In this paper ...

Arthur L. Schoenstadt

1980-08-01T23:59:59.000Z

192

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

193

Improving High-Resolution Numerical Weather Simulations by Assimilating Data from an Unmanned Aerial System  

Science Conference Proceedings (OSTI)

In this study, it is demonstrated how temperature, humidity, and wind profile data from the lower troposphere obtained with a lightweight unmanned aerial system (UAS) can be used to improve high-resolution numerical weather simulations by four-...

Marius O. Jonassen; Haraldur lafsson; Hlfdn gstsson; lafur Rgnvaldsson; Joachim Reuder

2012-11-01T23:59:59.000Z

194

Low-Resolution Numerical Simulation of Decaying Two-Dimensional Turbulence  

Science Conference Proceedings (OSTI)

Numerical simulations of two-dimensional turbulence show that O(??1) and O(??4) energy spectradescribed by Fox and Orszag (1973a) as enstrophy-equipartitioning and strongly dissipating turbulence, respectivelyoccur independently of the type of ...

Andrew F. Bennett; Dale B. Haidvogel

1983-03-01T23:59:59.000Z

195

Numerical Uncertainties in the Simulation of Reversible Isentropic Processes and Entropy Conservation  

Science Conference Proceedings (OSTI)

A challenge common to weather, climate, and seasonal numerical prediction is the need to simulate accurately reversible isentropic processes in combination with appropriate determination of sources/sinks of energy and entropy. Ultimately, this ...

Donald R. Johnson; Allen J. Lenzen; Tom H. Zapotocny; Todd K. Schaack

2000-11-01T23:59:59.000Z

196

Effects of Domain Size and Numerical Resolution on the Simulation of Shallow Cumulus Convection  

Science Conference Proceedings (OSTI)

The authors present three-dimensional numerical simulations of oceanic trade cumulus clouds underlying stratocumulus clouds. The case studied is a Global Energy and Water Experiment (GEWEX) Cloud System Study (GCSS) model intercomparison that is ...

David E. Stevens; Andrew S. Ackerman; Christopher S. Bretherton

2002-12-01T23:59:59.000Z

197

Numerical Simulation of Low-Frequency Current Fluctuations in Lake Michigan  

Science Conference Proceedings (OSTI)

Two simple numerical models have been used to study the low-frequency (Michigan in order to learn more about what really limits our ability to simulate currents in large lakes. Both are based on the ...

David J. Schwab

1983-12-01T23:59:59.000Z

198

Numerical simulation of the response of sandy soils treated with pre-fabricated vertical drains  

E-Print Network (OSTI)

This research is part of the ongoing effort of the Seismic Risk Mitigation for Port Systems Grand Challenge. It addresses the problem of numerically simulating the response of sandy soils treated with earthquake drains, ...

Vytiniotis, Antonios

2009-01-01T23:59:59.000Z

199

Numerical Simulation of Nocturnal Drainage Flows in Idealized ValleyTributary Systems  

Science Conference Proceedings (OSTI)

Numerical simulations of nocturnal drainage flow and transport in idealized valleytributary systems are compared with the Atmospheric Science in Complex Terrain (ASCOT) meteorological field data and tracer studies from the Brush Creek valley of ...

Lance B. OSteen

2000-11-01T23:59:59.000Z

200

The Rhine Outflow Plume Studied by the Analysis of Synthetic Aperture Radar Data and Numerical Simulations  

Science Conference Proceedings (OSTI)

The dynamics of the Rhine outflow plume in the proximity of the river mouth is investigated by using remote sensing data and numerical simulations. The remote sensing data consist of 41 synthetic aperture radar (SAR) images acquired by the First ...

Katrin Hessner; Angelo Rubino; Peter Brandt; Werner Alpers

2001-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Numerical simulation of ECRIPAC plasma behaviour with Vlasov equations including electron and ion collective effects  

E-Print Network (OSTI)

976 Numerical simulation of ECRIPAC plasma behaviour with Vlasov equations including electron of 4 MeV energy with very short pulses. (`ompared to ISlectron Ring Accelerators, ECRIPAC presents

Paris-Sud XI, Université de

202

Numerical Simulations of an Isolated Microburst. Part I: Dynamics and Structure  

Science Conference Proceedings (OSTI)

Isolated and stationary microbursts are simulated using a time-dependent, high-resolution, axisymmetric numerical model. A microburst downdraft is initiated by specifying a distribution of precipitation at the top boundary of the model and ...

Fred H. Proctor

1988-11-01T23:59:59.000Z

203

The Effects of Subgrid Model Mixing and Numerical Filtering in Simulations of Mesoscale Cloud Systems  

Science Conference Proceedings (OSTI)

Using the newly developed Weather Research and Forecasting (WRF) model, this study investigates the effects of subgrid mixing and numerical filtering in mesoscale cloud simulations by examining the sensitivities to the parameters in turbulence-...

Tetsuya Takemi; Richard Rotunno

2003-09-01T23:59:59.000Z

204

Improvements of an Ice-Phase Microphysics Parameterization for Use in Numerical Simulations of Tropical Convection  

Science Conference Proceedings (OSTI)

It is important to properly simulate the extent and ice water content of tropical anvil clouds in numerical models that explicitly include cloud formation because of the significant effects that these clouds have on the radiation budget. For this ...

Steven K. Krueger; Qiang Fu; K. N. Liou; Hung-Neng S. Chin

1995-01-01T23:59:59.000Z

205

Three-Dimensional Numerical Model Simulations of Airflow Over Mountainous Terrain: A Comparison with Observations  

Science Conference Proceedings (OSTI)

Numerical simulations of airflow over two different choices of mountainous terrain and the comparisons of results with aircraft observations are presented. Two wintertime casts for flow over Elk Mountain, Wyoming where surface heating is assumed ...

Terry L. Clark; Robert Gall

1982-07-01T23:59:59.000Z

206

Numerical Model Simulations of a Mesoscale Gravity Wave Event: Sensitivity Tests and Spectral Analyses  

Science Conference Proceedings (OSTI)

This study presents numerical model experiments and spectral investigations involving a mesoscale gravity wave event. Its purposes are to determine the sensitivity of mesoscale gravity wave simulation to model configuration and physics and to ...

Jordan G. Powers

1997-08-01T23:59:59.000Z

207

Numerical Simulations of Local Circulation and Cumulus Generation over the Loess Plateau, China  

Science Conference Proceedings (OSTI)

The Loess Plateau of China consists of dissected flat tablelands with steep gullies. To evaluate the effect of topography on local circulation and cumulus generation over the Loess Plateau, numerical simulations of atmospheric boundary layer (ABL)...

Masanori Nishikawa; Tetsuya Hiyama; Kazuhisa Tsuboki; Yoshihiro Fukushima

2009-04-01T23:59:59.000Z

208

Direct Numerical Simulation of the Turbulent Ekman Layer: Evaluation of Closure Models  

Science Conference Proceedings (OSTI)

A direct numerical simulation (DNS) at a Reynolds number of 1000 was performed for the neutral atmospheric boundary layer (ABL) using the Ekman layer approximation. The DNS results were used to evaluate several closure approximations that model ...

Stuart Marlatt; Scott Waggy; Sedat Biringen

2012-03-01T23:59:59.000Z

209

Direct Numerical Simulations of a Smoke CloudTop Mixing Layer as a Model for Stratocumuli  

Science Conference Proceedings (OSTI)

A radiatively driven cloud-top mixing layer is investigated using direct numerical simulations. This configuration mimics the mixing process across the inversion that bounds the stratocumulus-topped boundary layer. The main focus of this paper is ...

Alberto de Lozar; Juan Pedro Mellado

2013-08-01T23:59:59.000Z

210

The Sensitivity of Numerically Simulated Cyclic Mesocyclogenesis to Variations in Model Physical and Computational Parameters  

Science Conference Proceedings (OSTI)

In a previous paper, a three-dimensional numerical model was used to study the evolution of successive mesocyclones produced by a single supercell storm, that is, cyclic mesocyclogenesis. Not all supercells, simulated or observed, exhibit this ...

Edwin J. Adlerman; Kelvin K. Droegemeier

2002-11-01T23:59:59.000Z

211

Structure and Evolution of the 22 February 1993 TOGA COARE Squall Line: Numerical Simulations  

Science Conference Proceedings (OSTI)

In this study a numerical cloud model is used to simulate the three-dimensional evolution of an oceanic tropical squall line observed during the Tropical Ocean Global Atmosphere Coupled OceanAtmosphere Response Experiment and investigate the ...

S. B. Trier; W. C. Skamarock; M. A. LeMone; D. B. Parsons; D. P. Jorgensen

1996-10-01T23:59:59.000Z

212

Numerical Simulation of Organized Convection. Part I: Model Description and Preliminary Comparisons with Squall Line Observations  

Science Conference Proceedings (OSTI)

A numerical model designed for the simulations of mesoscale flows perturbed by deep convective clouds is discussed. It is based on the time dependent coupling between a three-dimensional nonhydrostatic mesoscale model and a quasi-one-dimensional ...

Yves Pointin

1985-01-01T23:59:59.000Z

213

Numerical simulations of ion transport membrane oxy-fuel reactors for CO? capture applications  

E-Print Network (OSTI)

Numerical simulations were performed to investigate the key features of oxygen permeation and hydrocarbon conversion in ion transport membrane (ITM) reactors. ITM reactors have been suggested as a novel technology to enable ...

Hong, Jongsup

2013-01-01T23:59:59.000Z

214

Estimation of Wind-Induced Error of Rainfall Gauge Measurements Using a Numerical Simulation  

Science Conference Proceedings (OSTI)

A new method of estimating the wind-induced error of rainfall gauge measurements is presented. The method is based on a three-dimensional numerical simulation of the airflow around a precipitation gauge and subsequent computation of particle ...

Vladislav Nepor; Boris Sevruk

1999-04-01T23:59:59.000Z

215

The Formation of Comma Vortices in a Tropical Numerical Simulation Model  

Science Conference Proceedings (OSTI)

A detailed analysis of a numerically simulated tropical disturbance displays a comma-shaped pattern at the mature stage in the low-level vorticity, surface convergence, mid-level upward motion and precipitation fields.

Robert E. Tuleya; Yoshio Kurihara

1984-03-01T23:59:59.000Z

216

The Evolution of an Observed Cold Front. Part I. Numerical Simulation  

Science Conference Proceedings (OSTI)

The 48 h evolution of an observed cold front is simulated by a three-dimensional mesoscale-numerical model for a typical springtime synoptic situation over the southeastern United States. The model used in this study employs anelastic equations ...

Bruce B. Ross; Isidoro Orlanski

1982-02-01T23:59:59.000Z

217

Numerical Simulations of a Buoyancy-Driven Coastal Countercurrent off Vancouver Island  

Science Conference Proceedings (OSTI)

A three-dimensional prognostic numerical model has been developed to study the ocean circulation around Vancouver Island, British Columbia. In a series of simulations, the model is applied to examine the role of buoyancy forcing in the dynamics ...

Diane Masson; Patrick F. Cummins

1999-03-01T23:59:59.000Z

218

Tornadogenesis Resulting from the Transport of Circulation by a Downdraft: Idealized Numerical Simulations  

Science Conference Proceedings (OSTI)

Idealized numerical simulations are conducted in which an axisymmetric, moist, rotating updraft free of rain is initiated, after which a downdraft is imposed by precipitation loading. The experiments are designed to emulate a supercell updraft ...

Paul M. Markowski; Jerry M. Straka; Erik N. Rasmussen

2003-03-01T23:59:59.000Z

219

Numerical Simulation of Pollutant Emission and Flame Extinction in Lean Premixed Systems .  

E-Print Network (OSTI)

??Premixed and partially-premixed combustion and ollutant emissions in full-scale gas turbines has been numerically investigated using a massively-parallel Large-Eddy Simulation Combustion Dynamics Model. Through the (more)

Eggenspieler, Gilles

2005-01-01T23:59:59.000Z

220

Numerical Uncertainties in Simulation of Reversible Isentropic Processes and Entropy Conservation: Part II  

Science Conference Proceedings (OSTI)

The objectives of this study are 1) to provide the framework for an in-depth statistical analysis of the numerical uncertainties in the simulation of conservation of entropy, potential vorticity, and like properties under appropriate modeling ...

Donald R. Johnson; Allen J. Lenzen; Tom H. Zapotocny; Todd K. Schaack

2002-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Three-Dimensional Numerical Simulation of Plume Downwash with a k? Turbulence Model  

Science Conference Proceedings (OSTI)

Plume downwash at a large oil-gathering facility in the Prudhoe Bay, Alaska oil-field reservation was simulated in a series of numerical experiments. The purpose of this study was to investigate the potential of the numerical model as a means of ...

Alex Guenther; Brian Lamb; David Stock

1990-07-01T23:59:59.000Z

222

Numerical Simulations of Temperature Field of Coal-Bed Methane with Heat Injection Based on ANSYS  

Science Conference Proceedings (OSTI)

The three-dimensional temperature field of the coal-bed methane with heat injection was numerically calculated by ANSYS. The calculated results revealed that the temperature, the thermal gradients and the thermal flux vector sum of the coal-bed near ... Keywords: heat injection, numerical simulation, temperature

Bing Xiong Lu

2012-03-01T23:59:59.000Z

223

Numerical simulation of optical feedback on a quantum dot lasers  

Science Conference Proceedings (OSTI)

We use multi-population rate equations model to study feedback oscillations in the quantum dot laser. This model takes into account all peculiar characteristics in the quantum dots such as inhomogeneous broadening of the gain spectrum, the presence of the excited states on the quantum dot and the non-confined states due to the presence of wetting layer and the barrier. The contribution of quantum dot groups, which cannot follow by other models, is simulated. The results obtained from this model show the feedback oscillations, the periodic oscillations which evolves to chaos at higher injection current of higher feedback levels. The frequency fluctuation is attributed mainly to wetting layer with a considerable contribution from excited states. The simulation shows that is must be not using simple rate equation models to express quantum dots working at excited state transition.

Al-Khursan, Amin H., E-mail: ameen_2all@yahoo.com [Thi-Qar University, Nassiriya Nanotechnology Research Laboratory (NNRL), Science College (Iraq); Ghalib, Basim Abdullattif [Babylon University, Laser Physics Department, Science College for Women (Iraq); Al-Obaidi, Sabri J. [Al-Mustansiriyah University, Physics Department, Science College (Iraq)

2012-02-15T23:59:59.000Z

224

Direct Numerical Simulation Of Solidification Microstructures Affected By Fluid Flow  

E-Print Network (OSTI)

The effects of fluid flow on the solidification morphology of pure materials and solute microsegregation patterns of binary alloys are studied using a computational methodology based on a front tracking/finite difference method. A general single-field formulation is presented for the full coupling of phase change, fluid flow, heat and solute transport. This formulation accounts for interfacial rejection/absorption of latent heat and solute, interfacial anisotropies, discontinuities in material properties between the liquid and solid phases, shrinkage/expansion upon solidification and motion and deformation of the solid. Numerical results are presented for the two-dimensional dendritic solidification of pure succinonitrile and the solidification of globulitic grains of a Plutonium-Gallium alloy. For both problems, comparisons are made between solidification without fluid flow and solidification within a shear flow. Introduction Nearly all materials of engineering interest have, at som...

Damir Juric

1998-01-01T23:59:59.000Z

225

Numerical simulation of laminar reacting flows with complex chemistry  

SciTech Connect

We present an adaptive algorithm for low Mach number reacting flows with complex chemistry. Our approach uses a form of the low Mach number equations that discretely conserves both mass and energy. The discretization methodology is based on a robust projection formulation that accommodates large density contrasts. The algorithm uses an operator-split treatment of stiff reaction terms and includes effects of differential diffusion. The basic computational approach is embedded in an adaptive projection framework that uses structured hierarchical grids with subcycling in time that preserves the discrete conservation properties of the underlying single-grid algorithm. We present numerical examples illustrating the performance of the method on both premixed and non-premixed flames.

Day, Marcus S.; Bell, John B.

1999-12-01T23:59:59.000Z

226

Three dimensional numerical simulations of the UPS-292-SC engine  

DOE Green Energy (OSTI)

We present and analyze three-dimensional calculations of the spray, mixing and combustion in the UPS-292 stratified charge engine for three different operating conditions, corresponding to overall air-fuel ratios between 22.4 and 61.0. The numerical calculations are performed with KIVA, a multidimensional arbitrary-mesh, finite-difference hydrodynamics program for internal combustion engine applications. The calculations use a mesh of 10,000 computational cells, which conform to the shape of the piston bowl and cylinder and move to follow piston motion. Each operating condition is calculated from intake valve closure at 118/sup 0/ BTDC to 90/sup 0/ ATDC and requires approximately three hours of CRAY-XMP computer time.

O'Rourke, P.J.; Amsden, A.A.

1987-01-01T23:59:59.000Z

227

Simple numerical simulation for liquid dominated geothermal reservoir  

SciTech Connect

A numerical model for geothermal reservoir has been developed. The model used is based on an idealized, two-dimensional case, where the porous medium is isotropic, nonhomogeneous, filled with saturated liquid. The fluids are assumed to have constant and temperature dependent viscosity. A Boussinesq approximation and Darcys law are used. The model will utilize a simple hypothetical geothermal system, i.e. graben within horsts structure, with three layers of different permeabilities. Vorticity plays an importance roles in the natural convection process, and its generation and development do not depend only on the buoyancy, but also on the magnitude and direction relation between the flow velocity and the local gradient of permeability to viscosity ratio. This model is currently used together with a physical, scaled-down reservoir model to help conceptual modeling.

Wintolo, Djoko; Sutrisno; Sudjatmiko; Sudarman, S.

1996-01-24T23:59:59.000Z

228

Numerical Simulations of Leakage from Underground LPG Storage Caverns  

SciTech Connect

To secure a stable supply of petroleum gas, underground storage caverns for liquified petroleum gas (LPG) are commonly used in many countries worldwide. Storing LPG in underground caverns requires that the surrounding rock mass remain saturated with groundwater and that the water pressure be higher than the liquid pressure inside the cavern. In previous studies, gas containment criteria for underground gas storage based on hydraulic gradient and pressure have been discussed, but these studies do not consider the physicochemical characteristics and behavior of LPG such as vaporization and dissolution in groundwater. Therefore, while these studies are very useful for designing storage caverns, they do not provide better understanding of the either the environmental effects of gas contamination or the behavior of vaporized LPG. In this study, we have performed three-phase fluid flow simulations of gas leakage from underground LPG storage caverns, using the multiphase multicomponent nonisothermal simulator TMVOC (Pruess and Battistelli, 2002), which is capable of solving the three-phase nonisothermal flow of water, gas, and a multicomponent mixture of volatile organic chemicals (VOCs) in multidimensional heterogeneous porous media. A two-dimensional cross-sectional model resembling an actual underground LPG facility in Japan was developed, and gas leakage phenomena were simulated for three different permeability models: (1) a homogeneous model, (2) a single-fault model, and (3) a heterogeneous model. In addition, the behavior of stored LPG was studied for the special case of a water curtain suddenly losing its function because of operational problems, or because of long-term effects such as clogging of boreholes. The results of the study indicate the following: (1) The water curtain system is a very powerful means for preventing gas leakage from underground storage facilities. By operating with appropriate pressure and layout, gas containment can be ensured. (2) However , in highly heterogeneous media such as fractured rock and fault zones, local flow paths within which the gas containment criterion is not satisfied could be formed. To eliminate such zones, treatments such as pre/post grouting or an additional installment of water-curtain boreholes are essential. (3) Along highly conductive features such as faults, even partially saturated zones possess certain effects that can retard or prevent gas leakage, while a fully unsaturated fault connected to the storage cavern can quickly cause a gas blowout. This possibility strongly suggests that ensuring water saturation of the rock surrounding the cavern is a very important requirement. (4) Even if an accident should suddenly impair the water curtain, the gas plume does not quickly penetrate the ground surface. In these simulations, the plume takes several months to reach the ground surface.

Yamamoto, Hajime; Pruess, Karsten

2004-09-01T23:59:59.000Z

229

Evaluation of Residential Hot Water Distribution Ssytems by Numeric Simulation  

SciTech Connect

The objective of this project was to evaluate the performance and economics of various domestic hot water distribution systems in representative California residences. While the greatest opportunities for improved efficiency occur in new construction, significant improvements can also be made in some existing distribution systems. Specific objectives of the project tasks were: (1) Simulate potential energy savings of, perform cost-benefit analyses of, and identify market barriers to alternative new systems. (2) Simulate potential energy savings of, perform cost-benefit analyses of, and identify market barriers to maintenance, repair, and retrofit modifications of existing systems. (3) Evaluate potential impact of adopting alternative hot water distribution systems and report project findings. The outcome of this project is to provide homeowners, homebuilders, systems suppliers, municipal code officials and utility providers (both electric and water/sewer) with a neutral, independent, third party, cost-benefit analysis of alternative hot water distribution systems for use in California. The results will enable these stakeholders to make informed decisions regarding which system is most appropriate for use.

Wendt, ROBERT

2005-08-17T23:59:59.000Z

230

Numerical Simulations of the Foehn in the Rhine Valley on 24 October 1999 (MAP IOP 10)  

Science Conference Proceedings (OSTI)

This paper presents numerical simulations of the MAP IOP 10 foehn case (24 October 1999) for the lower Alpine Rhine Valley, which was one of the two target areas selected for foehn observations. The simulations have been performed with a modified ...

Gnther Zngl; Barbara Chimani; Christian Hberli

2004-01-01T23:59:59.000Z

231

Numerical simulation of air/water multiphase flows for ceramic sanitary ware design by multiple GPUs  

E-Print Network (OSTI)

8 Numerical simulation of air/water multiphase flows for ceramic sanitary ware design by multiple Compounds A Large-scale Simulation on CFD in Construction Industry Estimation of strong ground motion and manufacturing of plumbing products such as ceramic sanitary wares. In order to re-produce the complex

232

A Numerical Model for the Dynamic Simulation of a Recirculation Single-Effect Absorption Chiller  

E-Print Network (OSTI)

A Numerical Model for the Dynamic Simulation of a Recirculation Single- Effect Absorption Chiller A dynamic model for the simulation of a new single-effect water/lithium bromide absorption chiller. Keywords: absorption; chiller; modelling; transient; water-lithium bromide; falling film hal-00713904

Recanati, Catherine

233

Life Cycle of Numerically Simulated Shallow Cumulus Clouds. Part II: Mixing Dynamics  

Science Conference Proceedings (OSTI)

This paper is the second in a two-part series in which life cycles of six numerically simulated shallow cumulus clouds are systematically examined. The six clouds, selected from a single realization of a large-eddy simulation, grow as a series of ...

Ming Zhao; Philip H. Austin

2005-05-01T23:59:59.000Z

234

Massively parallel direct numerical simulations of forced compressible turbulence: a hybrid MPI/OpenMP approach  

Science Conference Proceedings (OSTI)

A highly scalable simulation code for turbulent flows which solves the fully compressible Navier-Stokes equations is presented. The code, which supports one, two and three dimensional domain decompositions is shown to scale well on up to 262,144 cores. ... Keywords: direct numerical simulations, multilevel parallelism, parallel performance, turbulent flows

Shriram Jagannathan; Diego A. Donzis

2012-07-01T23:59:59.000Z

235

Structural collapse simulation under consideration of uncertainty - Improvement of numerical efficiency  

Science Conference Proceedings (OSTI)

The focus in this paper is set on the improvement of the numerical efficiency of a fuzzy stochastic structural collapse simulation. The deterministic computation is performed with an FE-model taking into account large deformations, contact phenomena ... Keywords: Finite element simulation, Fuzzy randomness, Neural network, Response surface methodology, Structural collapse, Uncertainty

Bernd Mller; Martin Liebscher; Karl Schweizerhof; Steffen Mattern; Gunther Blankenhorn

2008-10-01T23:59:59.000Z

236

On the numerical simulation of Kerr frequency combs using coupled mode equations  

E-Print Network (OSTI)

It is demonstrated that Kerr frequency comb generation described by coupled mode equations can be numerically simulated using Fast Fourier Transform methods. This allows broadband frequency combs spanning a full octave to be efficiently simulated using standard algorithms, resulting in orders of magnitude improvements in the computation time.

Hansson, T; Wabnitz, S

2013-01-01T23:59:59.000Z

237

Time-stepping numerical simulation of switched circuits within the nonsmooth dynamical systems approach  

Science Conference Proceedings (OSTI)

The numerical integration of switching circuits is known to be a tough issue when the number of switches is large, or when sliding modes exist. Then, classical analog simulators may behave poorly, or even fail. In this paper, it is shown on two examples ... Keywords: analog simulation, backward Euler algorithm, complementarity dynamical systems, complementarity problems, multivalued systems, power converters, switching circuits, unilateral state constraints

Vincent Acary; Olivier Bonnefon; Bernard Brogliato

2010-07-01T23:59:59.000Z

238

Development of a carburizing and quenching simulation tool: numerical simulations of rings and gears  

DOE Green Energy (OSTI)

The ability to accurately calculate temperatures, stresses and metallurgical transformations in a single calculation or in a sequence of calculations is the key to prediction of distortion, residual stress and phase distribution in quench hardened automotive parts. Successful predictions in turn rely on the adequacy of the input data to the calculational procedure. These data include mechanical and thermal properties of the alloy phases over the range of temperature and strain rates experienced during the heat treat process, the mathematical description of the transformation kinetics, and the accuracy of the heat transfer boundary conditions. In this presentation we describe a calculational procedure using the ABAQUS{sup (1)} finite element code that simulates a carburizing and quench heat treat cycle for automotive gears. The calculational procedure features a numerically efficient 2-phase constitutive model, developed as part of the NCMS-Heat Treatment Distortion Prediction program, to represent transformational plasticity effects for the austenite/martensite Deformation together with refined finite element meshes to capture the steep gradients in stress and composition near the gear surfaces. The calculational procedure is illustrated on carburizing and quenching of a thick ring and comparison of model predictions for distortion, phase distribution, and residual stress with experimental measurements are discussed. Included in this model study is an investigation of the sensitivity of the predictions to mesh refinement.

Anderson, C.; Godlman, P.; Rangaswamy, P. [and others

1996-10-01T23:59:59.000Z

239

Acceleration of heavy and light particles in turbulence: comparison between experiments and direct numerical simulations  

E-Print Network (OSTI)

We compare experimental data and numerical simulations for the dynamics of inertial particles with finite density in turbulence. In the experiment, bubbles and solid particles are optically tracked in a turbulent flow of water using an Extended Laser Doppler Velocimetry technique. The probability density functions (PDF) of particle accelerations and their auto-correlation in time are computed. Numerical results are obtained from a direct numerical simulation in which a suspension of passive pointwise particles is tracked, with the same finite density and the same response time as in the experiment. We observe a good agreement for both the variance of acceleration and the autocorrelation timescale of the dynamics; small discrepancies on the shape of the acceleration PDF are observed. We discuss the effects induced by the finite size of the particles, not taken into account in the present numerical simulations.

R. Volk; E. Calzavarini; G. Verhille; D. Lohse; N. Mordant; J. -F. Pinton; F. Toschi

2007-10-17T23:59:59.000Z

240

A numerical simulation of slantwise convection: its structure and evolution  

E-Print Network (OSTI)

Weather forecasters have had difficulty forecasting mesoscale precipitation bands occurring in the regions of frontal zones. Within the last twenty years, slantwise convection (SC) through the release of conditional symmetric instability (CSI) has gained more acceptance as the cause of the rainbands under certain conditions. Bennetts and Hoskins (1979) predict that under saturated conditions, CSI would be released, forming slantwise roll circulations with sloping updrafts and downdrafts (slantwise convection), and could be a possible explanation for frontal rainbands. This study uses the Penn State/NCAR Mesoscale Model (MM5) as a diagnostic tool to simulate a slantwise convective case from the Genesis of Atlantic Lows Experiment (GALE, Dirks et al. 1988) intensive observing period 1 (IOP1, 18 January 1986 to 20 January 1986). The model results show that SC formed in an 'upscale' development as suggested by Xu (1986) with SC dominating over upright convection. The results showed that in SC's development stage, the beginning of a roll circulation with a slanted updraft and a broad downdraft with a rear inflow jet. SC in its mature stage exhibits a well developed roll circulation, a 3-dimensional structure with along-line variability, stages of re-development suggesting a quasi-steady state, and the non-conservation of negative equivalent potential vorticity (-EPV). Eventually, SC decays as it can no longer generate CSI for release. The SC compared well with other SC bands in the event and showed similar structure as observed in radar data.

Overpeck, Scott Allen

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Numerical Simulations of Quantum Many-body Systems  

Science Conference Proceedings (OSTI)

The goals of our DOE work were to develop numerical tools in order to (1) determine the actual phase of particular many-electron models and (2) to understand the underlying mechanisms responsible for the observed phases. Over the years, DOE funds provided support for a number of graduate students and postdoctoral fellows who have gone on to continue and extend this effort. Looking back, they were more successful in determining the types of correlations that developed in particular models and less successful in establishing the underlying mechanisms. For example, they found clear evidence for antiferromagnetism, d{sub x{sup 3}-y{sup 2}}-pairing correlations, and stripes in various t-t{prime}-J and Hubbard models. Here, the stripes consisted of 1/2-filled domain walls of holes separated by {pi}-phase shifted antiferromagnetic regions. They found that a next-near-neighbor hopping t{prime} with t{prime}/t > 0 suppressed the stripes and favored the d{sub x{sup 3}-y{sup 2}}-pairing correlations. They studied a model of a CuO, 2-leg ladder and found that d{sub x{sup 3}-y{sup 2}} correlations formed when the system was doped with either electrons or holes. Another example that they studied was a two-dimensional spin 1/2 easy plane model with a near-neighbor exchange J and a four-site ring exchange K. In this J-K model, as K/J is increased, one moves from XY order to stripe order and to Ising antiferromagnetic order. They are still exploring the unusual transition between the Xy and striped phase. The key feature that we found was that strongly-correlated, many-electron systems are 'delicately balanced' between different possible phases. They also believe that their work provides strong support in favor of Anderson's suggestion that the Hubbard model contains the basic physics of the cuprates. That is, it exhibits antiferromagnetism, d{sub x{sup 3}-y{sup 2}}-pairing correlations, and stripes as the half-filled model is doped with holes. They were not as successful in determining the basic mechanisms. Specifically, they sought to determine the basic pairing mechanism. They tried various approaches and concluded that the spin-fluctuations play a central role. However, it was only recently, with Professor Mark Jarrell (UC) and Dr. Thomas Maier (ORNL), that they have found clear evidence that the pairing is mediated by an S = 1 particle-hole fluctuation.

Scalapino, Douglas J. Sugar, Robert L.

1998-04-20T23:59:59.000Z

242

Self-compression by femtosecond pulse filamentation: Experiments versus numerical simulations  

SciTech Connect

We analyze pulse self-compression in femtosecond filaments, both experimentally and numerically. We experimentally demonstrate the compression of 45 fs pulses down to a duration of 7.4 fs at millijoule pulse energies. This sixfold compression in a self-generated filament does not require any means for dispersion compensation and is highly efficient. We compare our results to numerical simulations, providing a complete propagation model that accounts for full dispersion, pressure variations, Kerr nonlinearity and plasma generation in multiphoton and tunnel regimes. The equations are numerically integrated and allow for a quantitative comparison with the experiment. Our experiments and numerical simulations reveal a characteristic spectrotemporal structure of the self-compressed pulses, consisting of a compressible blue wing and an incompressible red pedestal. We explain the underlying mechanism that leads to this structure and examine the scalability of filament self-compression with respect to pulse energy and gas pressure.

Skupin, Stefan; Berge, Luc [Departement de Physique Theorique et Appliquee, CEA-DAM/Ile de France, B.P. 12, 91680 Bruyeres-le-Chatel (France); Stibenz, Gero; Sokollik, Thomas; Schnuerer, Matthias; Zhavoronkov, Nickolai; Steinmeyer, Guenter [Max-Born-Institut fuer Nichtlineare Optik und Kurzzeitspektroskopie, Max-Born-Strasse 2a, 12489 Berlin (Germany); Lederer, Falk [Institute for Condensed Matter Theory and Solid State Optics, Friedrich-Schiller-Universitaet Jena, Max-Wien-Platz 1, 07743 Jena (Germany)

2006-11-15T23:59:59.000Z

243

Direct Numerical Simulation of Autoiginition of a Hydrogen Jet in a  

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

Direct Numerical Simulation of Autoiginition of a Hydrogen Jet in a Direct Numerical Simulation of Autoiginition of a Hydrogen Jet in a Preheated Cross Flow Submitted by mkaczmar on June 4, 2013 - 13:52 Authors: Abdilghanie, A., Frouzakis, C.E., Fischer, P Autoignition of a nitrogen-diluted hydrogen mixture issuing from a round nozzle into a cross-flowing turbulent stream of preheated air flowing in a channel at a friction Reynolds number Re = 180 is inves- tigated via 3-D direct numerical simulations (DNS) at two crossflow stream temperatures (930 and 950 K). Three-dimensional visualizations of the JICF reveal a complicated flow structure characterized by a variety of coherent vortical structures resulting from the boundary layers near the walls and evolving from the jet instabilities. The mean pressure field set up by the flow

244

Numerical Simulation of the Irish Wind Climate and Comparison with Wind  

Open Energy Info (EERE)

Numerical Simulation of the Irish Wind Climate and Comparison with Wind Numerical Simulation of the Irish Wind Climate and Comparison with Wind Atlas Data Dataset Summary Description (Abstract): The wind climate of Ireland has been calculated using the Karlsruhe Atmospheric Mesoscale Model KAMM using the statistical-dynamical method. The large-scale climatology is represented by 65 classes of geostropic wind. From the frequency of the classes and the simulations the climatology of the surface wind is determined. The simulated winds are processed similar to observed data to obtain LIB-files for the Wind Atlas Analysis and Application Program WAsP. Comparisons are made with mast observations which have been analyzed by WAsP. Sites with high wind power potential are well predicted. Stations with low power are over predicted. (Purpose): Article describing an example of a KAMM

245

Effect of Sea Breeze on Air Pollution in the Greater Athens Area. Part I: Numerical Simulations and Field Observations  

Science Conference Proceedings (OSTI)

Numerical simulations compared with field measurements are used to explain the effect of sea breezes on photochemical smog episodes in Athens during the Mediterranean Campaign of Photochemical Tracers on 1214 September 1994. The numerical ...

Alain Clappier; Alberto Martilli; Paola Grossi; Philippe Thunis; Francesco Pasi; Bernd C. Krueger; Bertrand Calpini; Giovanni Graziani; Hubert van den Bergh

2000-04-01T23:59:59.000Z

246

The Impact of Assimilating Satellite-Derived Precipitation Rates on Numerical Simulations of the ERICA IOP 4 Cyclone  

Science Conference Proceedings (OSTI)

The present study uses a regional-scale numerical model to test the impact of dynamically assimilating, satellite-derived precipitation rates on the numerical simulations of one of the deepest extratropical cyclones to develop south of 40N in ...

John Manobianco; Steven Koch; V. Mohan Karyampudi; Andrew J. Negri

1994-02-01T23:59:59.000Z

247

Numerical simulation of a lattice polymer model at its integrable point  

E-Print Network (OSTI)

We revisit an integrable lattice model of polymer collapse using numerical simulations. This model was first studied by Bl\\"ote and Nienhuis in J. Phys. A. {\\bf 22}, 1415 (1989) and it describes polymers with some attraction, providing thus a model for the polymer collapse transition. At a particular set of Boltzmann weights the model is integrable and the exponents $\

A. Bedini; A. L. Owczarek; T. Prellberg

2012-11-01T23:59:59.000Z

248

Fictitious boundary and moving mesh methods for the numerical simulation of rigid particulate flows  

Science Conference Proceedings (OSTI)

In this paper, we investigate the numerical simulation of particulate flows using a new moving mesh method combined with the multigrid fictitious boundary method (FBM) [S. Turek, D.C. Wan, L.S. Rivkind, The fictitious boundary method for the implicit ... Keywords: ALE, FEM, Fictitious boundary, Moving mesh, Multigrid, Particulate flows

Decheng Wan; Stefan Turek

2007-03-01T23:59:59.000Z

249

Boiler Room Coal Drying Heat Exchanger Numerical Computational Simulation and Analysis  

Science Conference Proceedings (OSTI)

Northeast area city district heating boiler room of coal with high moisture content, have caused a large number of waste of coal resources. Boiler coal drying heat exchanger is a long design cycle, testing workload and investment is more equipment. In ... Keywords: District heating boiler room, Dry heat exchanger, Numerical simulation, Heat transfer calculation

Zhao Xuefeng, Xiong Wen-zhuo

2012-07-01T23:59:59.000Z

250

Numerical Simulation of Late Wintertime Local Flows in Kathmandu Valley, Nepal: Implication for Air Pollution Transport  

Science Conference Proceedings (OSTI)

Air pollution transport in the Kathmandu valley/basin has been investigated by numerical simulation of local flows and the observation of NO2 and SO2. The observation was performed at 22 sites with passive samplers from February to April 2001, ...

Ram P. Regmi; Toshihiro Kitada; Gakuji Kurata

2003-03-01T23:59:59.000Z

251

Numerical simulation of steady and unsteady mixed convection from tubes of elliptic cross-section  

Science Conference Proceedings (OSTI)

The problem of two-dimensional laminar mixed convection (forced and free convection) from a tube of elliptic cross-section has been numerically simulated for the cases when the approaching flow is either steady or fluctuating. The elliptic cross-section ... Keywords: elliptic tube, fluctuating flow, heat transfer, mixed convection

H. M. Badr; E. H. Ahmed

2002-09-01T23:59:59.000Z

252

Numerical Simulation of Polar Lows and Comma Clouds Using Simple Dry Models  

Science Conference Proceedings (OSTI)

Linear and nonlinear numerical channel models are used to simulate polar low/comma cloud evolution. The purpose of this study is to see how much realism can be obtained using models that do not include water vapor. The study was inspired by ...

Stephen E. Mudrick

1987-12-01T23:59:59.000Z

253

Numerical simulation and analysis to tidal currents and wave field of pearl river  

Science Conference Proceedings (OSTI)

A hydrodynamic model (MOCOE) is used in tidal current and wave calculation in Yamen river, which is one of the eight estuaries of Pearl River. The method of combining curvilinear orthogonal coordinates in the horizontal direction with Sigma mapping coordinates ... Keywords: curvilinear orthogonal, numerical simulation, tidal currents

Wu Hongxu

2009-11-01T23:59:59.000Z

254

A high-order public domain code for direct numerical simulations of turbulent combustion  

Science Conference Proceedings (OSTI)

A high-order scheme for direct numerical simulations of turbulent combustion is discussed. Its implementation in the massively parallel and publicly available Pencil Code is validated with the focus on hydrogen combustion. This is the first open source ... Keywords: Public domain DNS code, Turbulent combustion

N. Babkovskaia; N. E. L. Haugen; A. Brandenburg

2011-01-01T23:59:59.000Z

255

Steam generators two phase flows numerical simulation with liquid and gas momentum equations  

E-Print Network (OSTI)

Steam generators two phase flows numerical simulation with liquid and gas momentum equations M dimensional two-phase (liquid and gas) flows. The main goal is to improve the mod- eling of kinetic imbalance between the phases. We present a method that solves the mix- ture (liquid-gas) mass and enthalpy equations

Paris-Sud XI, Université de

256

A Numerical Simulation Study on the Genesis of a Tropical Storm  

Science Conference Proceedings (OSTI)

The genesis of a tropical storm is studied using a numerical simulation model. The model used is an 11-level primitive equation model covering a channel domain of 25 span with open lateral boundaries at latitudes 5.5 and 30.5N. The initial ...

Yoshio Kurihara; Robert E. Tuleya

1981-08-01T23:59:59.000Z

257

Numerical Simulation of Land-Breeze-Induced Snowbands Along the Western Shore of Lake Michigan  

Science Conference Proceedings (OSTI)

Case studies are presented which describe a type of lake-effect snowband which forms along the western shore of Lake Michigan when a cold anticyclone to the north sets up an easterly gradient over the lake. Numerical simulations indicate that the ...

Robert J. Ballentine

1983-08-01T23:59:59.000Z

258

Numerical Simulation of Land-Breeze-Induced Snowbands Along the Western Shore of Lake Michigan  

Science Conference Proceedings (OSTI)

Case studies are presented which describe a type of lake-effect snowband which forms along the western shore of Lake Michigan when a cold anticyclone to the north sets up an easterly gradient over the lake. Numerical simulations indicate that the ...

Robert J. Ballentine

1982-11-01T23:59:59.000Z

259

Life Cycle of Numerically Simulated Shallow Cumulus Clouds. Part I: Transport  

Science Conference Proceedings (OSTI)

This paper is the first in a two-part series in which the life cycles of numerically simulated shallow cumulus clouds are systematically examined. The life cycle data for six clouds with a range of cloud-top heights are isolated from an ...

Ming Zhao; Philip H. Austin

2005-05-01T23:59:59.000Z

260

Loop Current Mixed Layer Energy Response to Hurricane Lili (2002). Part II: Idealized Numerical Simulations  

Science Conference Proceedings (OSTI)

In this second part of a two-part study, details of the upper-ocean response within an idealized baroclinic current to a translating tropical cyclone are examined in a series of nonlinear, reduced-gravity numerical simulations. Based on ...

Eric W. Uhlhorn; Lynn K. Shay

2013-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Numerical simulation of the shock wave / boundary layer interaction in a shock tube by  

E-Print Network (OSTI)

Numerical simulation of the shock wave / boundary layer interaction in a shock tube by using a high in a shock tube after the shock wave has reflected at the end wall. When the fluid is viscous, a complex unsteady interaction takes place between the reflected shock wave and the incident boundary layer

262

Numerical simulation of hydraulic shock in a water pumping system protected by air  

Science Conference Proceedings (OSTI)

Air may be efficiently used in water pumping system protection from hydraulic shock, due to its elasticity. The paper presents the results regarding the extreme pressures in the discharge duct of a pumping installation, obtained by numerical simulation ... Keywords: air chamber, biphasic flow, dissolution, hydraulic shock, pumping installation

Anca Constantin; Claudiu Stefan Nitescu

2010-10-01T23:59:59.000Z

263

Application and numerical simulation on water mist cooling for urban environment regulation  

Science Conference Proceedings (OSTI)

The fine water mist is a type of sustainable and environment-friendly cooling technology. This paper concerns the use of water mist flow to improve the quality of urban environment in summer. According to the survey and analysis on the potential for ... Keywords: numerical simulation, regulation of microclimate, spray cooling, two-phase flow

Junfeng Wang; Xincheng Tu; Zhentao Wang; Jiwei Huang

2010-09-01T23:59:59.000Z

264

Numerical simulation of a simplified conductive-convective system for 2D thermal field analysis  

Science Conference Proceedings (OSTI)

This paper presents an application simulated using finite element package within Comsol Multiphysics. This model of combined processes is exemplified to a cooling fin for an electronic device. As it is known, all electronic devices generate heat during ... Keywords: copper plate, heat sink, heat transfer rate, longitudinal fin, numerical computation, temperature field distribution

Diana Enescu; Elena Otilia Virjoghe; Marcel Ionel; Mihail-Florin Stan

2010-12-01T23:59:59.000Z

265

Simulation of a Stratocumulus-Topped Planetary Boundary Layer: Intercomparison among Different Numerical Codes  

Science Conference Proceedings (OSTI)

This paper reports an intercomparison study of a stratocumulus-topped planetary boundary layer (PBL) generated from ten 3D large eddy simulation (LES) codes and four 2D cloud-resolving models (CRMs). These models vary in the numerics, the ...

C-H. Moeng; W. R. Cotton; B. Stevens; C. Bretherton; H. A. Rand; A. Chlond; M. Khairoutdinov; S. Krueger; W. S. Lewellen; M. K. MacVean; J. R. M. Pasquier; A. P. Siebesma; R. I. Sykes

1996-02-01T23:59:59.000Z

266

Numerical Simulation of Episodes of Organized Convection in Tropical Northern Africa  

Science Conference Proceedings (OSTI)

A large-domain convection-permitting numerical model is used to simulate episodes of deep convection, which are generated during the day over the Ethiopian Highlands and then propagate westward over the eastern and central Sahel region (520N) ...

Arlene G. Laing; Stanley B. Trier; Christopher A. Davis

2012-09-01T23:59:59.000Z

267

Numerical simulation of melting in two-dimensional cavity using adaptive grid  

Science Conference Proceedings (OSTI)

This paper presents a numerical simulation of melting of chemically pure material in two-dimensional square cavity. A single-domain model is used which does not require interface tracking and allows the use of a fixed grid in order to solve governing ... Keywords: adaptive moving grid, grid generation, melting

Jure Mencinger

2004-07-01T23:59:59.000Z

268

Entrainment and Detrainment in Numerically Simulated Cumulus Congestus Clouds. Part I: General Results  

Science Conference Proceedings (OSTI)

This paper is the first in a three-part series in which a three-dimensional numerical model is run at high resolution to simulate cumulus congestus clouds in three dimensions with the principal goal of understanding the mechanisms associated with ...

Richard L. Carpenter Jr.; Kelvin K. Droegemeier; Alan M. Blyth

1998-12-01T23:59:59.000Z

269

DIVERGENCE-FREE AND CURL-FREE WAVELETS ON THE SQUARE FOR NUMERICAL SIMULATIONS  

E-Print Network (OSTI)

DIVERGENCE-FREE AND CURL-FREE WAVELETS ON THE SQUARE FOR NUMERICAL SIMULATIONS SOULEYMANE KADRI Grenoble cedex 9, France August 30, 2011 Abstract We present a construction of divergence-free and curl-free and integration. We introduce new BMRAs and wavelets for the spaces of divergence-free and curl-free vector

Paris-Sud XI, Université de

270

Numerical simulation of earthing grids IGNASI COLOMINAS, FERMIN NAVARRINA & MANUEL CASTELEIRO  

E-Print Network (OSTI)

, Numerical simulation 1 Introduction The "grounding" or "earthing" system of an electrical substation by the authors in the last years for the computational design of grounding systems of electrical installations in uniform and layered soils. Key­Words: Grounding grids, Boundary Element Method, Layered soil model

Colominas, Ignasi

271

Numerical simulation of multilayer grounding grids in a user-friendly open-source CAD interface  

E-Print Network (OSTI)

Numerical simulation of multilayer grounding grids in a user-friendly open-source CAD interface Jos application for the in-house computer aided design and analysis of grounding grids. The actual version the equivalent resistance and the step and touch voltage in most large electrical overground substations

Colominas, Ignasi

272

Numerical simulation of three-phase flow in heterogeneous porous media  

Science Conference Proceedings (OSTI)

We describe an efficient numerical simulator, based on an operator splitting technique, for three-phase flow in heterogeneous porous media that takes into account capillary forces, general relations for the relative permeability functions and variable ... Keywords: central difference scheme, mixed finite elements, non-classical waves, operator splitting, porous media, three-phase flow

Eduardo Abreu; Frederico Furtado; Felipe Pereira

2006-06-01T23:59:59.000Z

273

Numerical Simulation and Multiple Realizations for Sensitivity Study of Shale Gas Reservoir  

E-Print Network (OSTI)

SPE 141058 Numerical Simulation and Multiple Realizations for Sensitivity Study of Shale Gas. The abstract must contain conspicuous acknowledgment of SPE copyright. Abstract Shale gas in the United States the largest conventional gas accumulations in the world. Shale gas success is directly the result

Mohaghegh, Shahab

274

Numerical Simulation of Dust Lifting within Dust DevilsSimulation of an Intense Vortex  

Science Conference Proceedings (OSTI)

Based on an advanced dust devilscale large-eddy simulation (LES) model, the atmosphere flow of a modeled dust devil in a quasisteady state was first simulated to illustrate the characteristics of the gas phase field in the mature stage, ...

Zhaolin Gu; Yongzhi Zhao; Yun Li; Yongzhang Yu; Xiao Feng

2006-10-01T23:59:59.000Z

275

Numerical simulations of gun-launched kinetic energy projectiles subjected to asymmetric projectile base pressure  

SciTech Connect

Three-dimensional numerical simulations were performed to determine the effect of an asymmetric base pressure on kinetic energy projectiles during launch. A matrix of simulations was performed in two separate launch environments. One launch environment represented a severe lateral load environment, while the other represented a nonsevere lateral load environment based on the gun tube straightness. The orientation of the asymmetric pressure field, its duration, the projectile`s initial position, and the tube straightness were altered to determine the effects of each parameter. The pressure asymmetry translates down the launch tube to exit parameters and is washed out by tube profile. Results from the matrix of simulations are presented.

Rabern, D.A.

1991-12-31T23:59:59.000Z

276

Numerical simulations of gun-launched kinetic energy projectiles subjected to asymmetric projectile base pressure  

SciTech Connect

Three-dimensional numerical simulations were performed to determine the effect of an asymmetric base pressure on kinetic energy projectiles during launch. A matrix of simulations was performed in two separate launch environments. One launch environment represented a severe lateral load environment, while the other represented a nonsevere lateral load environment based on the gun tube straightness. The orientation of the asymmetric pressure field, its duration, the projectile's initial position, and the tube straightness were altered to determine the effects of each parameter. The pressure asymmetry translates down the launch tube to exit parameters and is washed out by tube profile. Results from the matrix of simulations are presented.

Rabern, D.A.

1991-01-01T23:59:59.000Z

277

Investigation of the eigenfrequencies of two interacting gas bubbles using the direct-numerical-simulation technique  

E-Print Network (OSTI)

The recent theory regarding the eigenfrequencies of two mutually interacting gas bubbles in an acoustic field is verified numerically. The theory given by Ida [e-Print physics/0111133; (submitted)] predicts the existence of three eigenfrequencies per bubble, which make the phase difference between a bubble's pulsation and an external sound be $\\pi / 2$, while readymade theories predict only two natural frequencies. The direct-numerical-simulation technique, in which the compressible Navier-Stokes equation is selected as the governing equation, is employed for numerical experiments. We investigate the eigenfrequencies by observing the direction of the secondary Bjerknes force acting between pulsating bubbles, which changes as the driving frequency varies. The numerical results show that the theoretical prediction is valid at least in a qualitative sense.

Ida, M

2001-01-01T23:59:59.000Z

278

Characterization of dielectric barrier discharge in air applying current measurement, numerical simulation and emission spectroscopy  

E-Print Network (OSTI)

Dielectric barrier discharge (DBD) in air is characterized applying current measurement, numerical simulation and optical emission spectroscopy (OES). For OES, a non-calibrated spectrometer is used. This diagnostic method is applicable when cross-sectional area of the active plasma volume and current density can be determined. The nitrogen emission in the spectral range of 380 nm- 406 nm is used for OES diagnostics. Electric field in the active plasma volume is determined applying the measured spectrum, well-known Frank-Condon factors for nitrogen transitions and numerically- simulated electron distribution functions. The measured electric current density is used for determination of electron density in plasma. Using the determined plasma parameters, the dissociation rate of nitrogen and oxygen in active plasma volume are calculated, which can be used by simulation of the chemical kinetics.

Rajasekaran, Priyadarshini; Awakowicz, Peter

2012-01-01T23:59:59.000Z

279

Analysis of the flamelet concept in the numerical simulation of laminar partially premixed flames  

Science Conference Proceedings (OSTI)

The aim of this work is to analyze the application of flamelet models based on the mixture fraction variable and its dissipation rate to the numerical simulation of partially premixed flames. Although the main application of these models is the computation of turbulent flames, this work focuses on the performance of flamelet concept in laminar flame simulations removing, in this way, turbulence closure interactions. A well-known coflow methane/air laminar flame is selected. Five levels of premixing are taken into account from an equivalence ratio {phi}={infinity} (nonpremixed) to {phi}=2.464. Results obtained using the flamelet approaches are compared to data obtained from the detailed solution of the complete transport equations using primitive variables. Numerical simulations of a counterflow flame are also presented to support the discussion of the results. Special emphasis is given to the analysis of the scalar dissipation rate modeling. (author)

Consul, R.; Oliva, A.; Perez-Segarra, C.D.; Carbonell, D. [Centre Tecnologic de Transferencia de Calor (CTTC), Universitat Politecnica de Catalunya (UPC), Colom 11, E-08222, Terrassa, Barcelona (Spain); de Goey, L.P.H. [Eindhoven University of Technology, Department of Mechanical Engineering, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2008-04-15T23:59:59.000Z

280

Sensitivity of Numerical Simulation of Early Rapid Intensification of Hurricane Emily (2005) to Cloud Microphysical and Planetary Boundary Layer Parameterizations  

Science Conference Proceedings (OSTI)

An advanced research version of the Weather Research and Forecasting (ARW) Model is used to simulate the early rapid intensification of Hurricane Emily (2005) using grids nested to high resolution (3 km). A series of numerical simulations is ...

Xuanli Li; Zhaoxia Pu

2008-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Diagnosis of the Initial and Forecast Errors in the Numerical Simulation of the Rapid Intensification of Hurricane Emily (2005)  

Science Conference Proceedings (OSTI)

A diagnostic study is conducted to examine the initial and forecast errors in a short-range numerical simulation of Hurricane Emilys (2005) early rapid intensification. The initial conditions and the simulated hurricane vortices using high-...

Zhaoxia Pu; Xuanli Li; Edward J. Zipser

2009-10-01T23:59:59.000Z

282

A Numerical Simulation of Amplification of Low-Frequency Planetary Waves and Blocking Formations by the Upscale Energy Cascade  

Science Conference Proceedings (OSTI)

In this study, nonlinear numerical simulations of amplification of low-frequency planetary waves and concurrent blocking formations were performed. The simulations are conducted by a barotropic spectral model derived from three-dimensional ...

H. L. Tanaka

1991-12-01T23:59:59.000Z

283

Numerical Simulations of the Genesis of Hurricane Diana (1984). Part II: Sensitivity of Track and Intensity Prediction  

Science Conference Proceedings (OSTI)

The authors examine numerous simulations that probe the dynamics governing the intensification and track of Tropical Cyclone Diana (1984) simulated in Part I. The development process is fundamentally dependent on a preexisting upper-tropospheric ...

Christopher Davis; Lance F. Bosart

2002-05-01T23:59:59.000Z

284

Numerical Simulation and Analysis of a Prefrontal Squall Line. Part I: Observations and Basic Simulation Results  

Science Conference Proceedings (OSTI)

An observational and numerical study of the squall line that occurred on 1718 June 1978 is presented. This squall line was initially triggered by the strong surface convergence along a cold front and stretched from Illinois to the Texas ...

Jennifer M. Cram; Roger A. Pielke; William R. Cotton

1992-02-01T23:59:59.000Z

285

Numerical simulation of the mitigating effects of an LNG vapor fence  

SciTech Connect

FEM3A, a fully three-dimensional numerical model for simulating the atmospheric dispersion of heavy gases involving complex geometry, has been used to investigate the mitigating effects of a vapor fence for LNG storage areas. In this paper, a brief description of the numerical model used to perform such calculations is given, the problem being simulated is described, and an intercomparison among the results from numerical simulations (with and without the vapor fence) and field data (with vapor fence) is made. The numerical results indicate that, with the present fence configuration, the maximum concentration on the cloud centerline was reduced by a factor of two or more within 250 m behind the fence, and the downwind distance to the 2.5% concentration was reduced from 365 m to 230 m. However, a vapor fence could also cause the vapor cloud to linger considerably longer in the source area, thus increasing the potential for ignition and combustion within the vapor fence and the area nearby over time. 8 refs., 10 figs.

Chan, S.T.

1990-05-01T23:59:59.000Z

286

Numerical simulation of the impeller tip clearance effect on centrifugal compressor performance  

E-Print Network (OSTI)

This thesis presents the numerical simulation of flow in centrifugal compressors. A three-dimensional Navier-Stokes solver was employed to simulate flow through two centrifugal compressors. The first compressor simulated was the NASA low speed centrifugal compressor (LSCC). The LSCC was selected as a test compressor because of the experimental data available. The numerically simulated data was compared to the experimental data to validate the flow solver. The numerical results were in good agreement with the experimental. The second compressor simulated was a Honeywell turbopump centrifugal compressor (HCC). The HCC was simulated for three tip clearances at six wheel speeds. Six operating conditions were investigated at each tip clearance and wheel speed. The data obtained from the HCC simulations was used to investigate the effect of tip clearance on compressor performance. Specifically, the total-total pressure ratio, mass flow rate and adiabatic efficiencies were tracked to see how each were affected by an increasing tip clearance. The results show that as the tip clearance was increased, the total-total pressure ratio, mass flow rate and adiabatic efficiencies all decreased for the same static-total pressure ratio. The pressure differences and temperature differences, from the pressure side to the suction side of the blade, and the vorticity were all explored as possible causes of this reduced performance. The pressure proved to be the biggest impactor on performance. The increased tip clearance let more flow leak across the blade tip. The leakage flow tried to homogenize the pressure difference across the blade. The overall effect resulted in a much lower pressure difference. The temperature remained nearly the same as the tip clearance increased. The vorticity increased, but this was also a result of the increased tip leakage flow. To aid in total-total pressure ratio predictions, the results for the HCC were put into compressor maps.

Hoenninger, Corbett Reed

2001-01-01T23:59:59.000Z

287

Numerical Classical and Quantum Mechanical simulations of Charge Density wave models  

E-Print Network (OSTI)

We first present how to do a computer simulation of Charge Density Waves using a driven harmonic oscillator model by a numerical scheme as initially formulated by Littlewood, and then afterwards use this to present how the dielectric model as presented by this proceedure leads to a blow up at the initialization of a threshold field ET. We find that this is highly unphysical and this initiated our inquiry as to alternative models. Afterwards, we then investigate hwo to present this transport problem of CDW quantum mechanically, threough a numerical simulation of the massive Schwinger model. We find that this single chaing quantum mechanical simulation uwed to formulate solutions to CDW transport in itself is insufficient for transport of solitons(anti-solitons) through a pinning gap model of CDW. We show that a model Hamiltonian with Peierls condensation energy used to couple adjacent chains (or transverse wave vectors) permits formation of solitons (anti- solitons) which can be used to transport CDW through a potential barrier. This addition of the Peierls condensation energy term is essential for any quantum model of Charge Density Waves to give tunneling behavior as seen via a numerical simulation.

A. W. Beckwith

2004-09-13T23:59:59.000Z

288

Numerical simulations of magnetospheric plasmas review and quadrennial report to the IUGG  

Science Conference Proceedings (OSTI)

This argicle provides a broad survey of U.S. progress during the quadrennium 1983-1986 in the category 'numerical simulations of magnetospheric plasmas'. There has been a substantial increase of activity in this area during this period. Simulations have been instrumental in providing valuable insights into large scale dynamic phenomena, nonlinear effects, and complex kinetic phenomena in a wide variety of subject areas, including shocks and double layers, ionosphere-magnetosphere coupling phenomena, and important microphysical processes such as broadband electrostatic noise. The methodology of computer simulation has also been advanced during this quadrennium. Vlasov algorithms have been improved; hybrid codes in 2 and 3D have been developed and applied to magnetospheric problems; and complex problems have with increasing frequency been subjected to a multipronged attack in which several types of simulation models, each designed to accurately model phenomena within a particular range of temporal or spatial scales, are employed synergistically. copyright American Geophysical Union 1987

Palmadesso, P.J.; Ganguli, S.B.; Fedder, J.A.; Lyon, J.G.

1987-04-01T23:59:59.000Z

289

VINE-A NUMERICAL CODE FOR SIMULATING ASTROPHYSICAL SYSTEMS USING PARTICLES. I. DESCRIPTION OF THE PHYSICS AND THE NUMERICAL METHODS  

Science Conference Proceedings (OSTI)

We present a numerical code for simulating the evolution of astrophysical systems using particles to represent the underlying fluid flow. The code is written in Fortran 95 and is designed to be versatile, flexible, and extensible, with modular options that can be selected either at the time the code is compiled or at run time through a text input file. We include a number of general purpose modules describing a variety of physical processes commonly required in the astrophysical community and we expect that the effort required to integrate additional or alternate modules into the code will be small. In its simplest form the code can evolve the dynamical trajectories of a set of particles in two or three dimensions using a module which implements either a Leapfrog or Runge-Kutta-Fehlberg integrator, selected by the user at compile time. The user may choose to allow the integrator to evolve the system using individual time steps for each particle or with a single, global time step for all. Particles may interact gravitationally as N-body particles, and all or any subset may also interact hydrodynamically, using the smoothed particle hydrodynamic (SPH) method by selecting the SPH module. A third particle species can be included with a module to model massive point particles which may accrete nearby SPH or N-body particles. Such particles may be used to model, e.g., stars in a molecular cloud. Free boundary conditions are implemented by default, and a module may be selected to include periodic boundary conditions. We use a binary 'Press' tree to organize particles for rapid access in gravity and SPH calculations. Modules implementing an interface with special purpose 'GRAPE' hardware may also be selected to accelerate the gravity calculations. If available, forces obtained from the GRAPE coprocessors may be transparently substituted for those obtained from the tree, or both tree and GRAPE may be used as a combination GRAPE/tree code. The code may be run without modification on single processors or in parallel using OpenMP compiler directives on large-scale, shared memory parallel machines. We present simulations of several test problems, including a merger simulation of two elliptical galaxies with 800,000 particles. In comparison to the Gadget-2 code of Springel, the gravitational force calculation, which is the most costly part of any simulation including self-gravity, is {approx}4.6-4.9 times faster with VINE when tested on different snapshots of the elliptical galaxy merger simulation when run on an Itanium 2 processor in an SGI Altix. A full simulation of the same setup with eight processors is a factor of 2.91 faster with VINE. The code is available to the public under the terms of the Gnu General Public License.

Wetzstein, M. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Nelson, Andrew F. [Los Alamos National Laboratory, HPC-5 MS B272, Los Alamos NM, 87545 (United States); Naab, T.; Burkert, A. [Universitaets-Sternwarte, Scheinerstr. 1, 81679 Muenchen (Germany)], E-mail: mwetz@usm.lmu.de

2009-10-01T23:59:59.000Z

290

A low numerical dissipation patch-based adaptive mesh refinement method for large-eddy simulation of compressible flows  

Science Conference Proceedings (OSTI)

We present a methodology for the large-eddy simulation of compressible flows with a low-numerical dissipation scheme and structured adaptive mesh refinement (SAMR). A description of a conservative, flux-based hybrid numerical method that uses both centered ... Keywords: Compressible flow, LES, Numerical methods, SAMR, Turbulence

C. Pantano; R. Deiterding; D. J. Hill; D. I. Pullin

2007-01-01T23:59:59.000Z

291

Numerical simulation of the laminar diffusion flame in a simplified burner. Revision 1  

DOE Green Energy (OSTI)

The laminar ethylene-air diffusion flame in a simple laboratory burner was simulated with the COYOTE reactive flow program. This program predicts the flow field, transport, and chemistry for the purposes of code validation and providing physical understanding of the processes occurring in the flame. The authors show the results of numerical experiments to test the importance of several physical phenomena, including gravity, radiation, and differential diffusion. The computational results compare favorably with the experimental measurements, and all three phenomena are important to accurate simulations.

Cloutman, L.D.

1996-02-01T23:59:59.000Z

292

Comparison of Numerical Simulators for Greenhouse Gas Storage in Coalbeds, Part I: Pure Carbon Dioxide Injection  

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

Comparison of Numerical Simulators for Greenhouse Gas Storage Comparison of Numerical Simulators for Greenhouse Gas Storage in Coalbeds, Part I: Pure Carbon Dioxide Injection David H.-S. Law (law@arc.ab.ca; 780-450-5034) Alberta Research Council (ARC) Inc. 250 Karl Clark Road, Edmonton, Alberta, Canada T6N 1E4 L.H.G. (Bert) van der Meer (l.vandermeer@nitg.tno.nl; +31-30-256-4635) Netherlands Institute of Applied Geoscience TNO P.O. Box 80015, 3508 TA Utrecht, The Netherlands W.D. (Bill) Gunter (gunter@arc.ab.ca; 780-450-5467) Alberta Research Council (ARC) Inc. 250 Karl Clark Road, Edmonton, Alberta, Canada T6N 1E4 Abstract The injection of carbon dioxide (CO 2 ) in deep, unmineable coalbeds is a very attractive option for geologic CO 2 storage: the CO 2 is stored and at the same time the recovery of

293

Numerical simulation of MHD for electromagnetic edge dam in continuous casting.  

DOE Green Energy (OSTI)

A computer model was developed to predict eddy currents and fluid flows in molten steel. The model was verified by comparing predictions with experimental results of liquid-metal containment and fluid flow in electromagnetic (EM) edge dams (EMDs) designed at Inland Steel for twin-roll casting. The model can optimize the EMD design so it is suitable for application, and minimize expensive, time-consuming full-scale testing. Numerical simulation was performed by coupling a three-dimensional (3-D) finite-element EM code (ELEKTRA) and a 3-D finite-difference fluids code (CaPS-EM) to solve heat transfer, fluid flow, and turbulence transport in a casting process that involves EM fields. ELEKTRA is able to predict the eddy-current distribution and the electromagnetic forces in complex geometries. CaPS-EM is capable of modeling fluid flows with free surfaces. Results of the numerical simulation compared measurements obtained from a static test.

Chang, F. C.

1999-03-30T23:59:59.000Z

294

Conservative numerical simulation of multi-component transport in two-dimensional unsteady shallow water flow  

Science Conference Proceedings (OSTI)

An explicit finite volume model to simulate two-dimensional shallow water flow with multi-component transport is presented. The governing system of coupled conservation laws demands numerical techniques to avoid unrealistic values of the transported ... Keywords: ?-? model, 35L65, 65M06, 65M12, 76M12, 76M20, Coupled system, Multi-component transport, Reactive source terms, Shallow flow, Solute constraints, Turbulence, Variable domain, Well-balanced approach

J. Murillo; P. Garca-Navarro; J. Burguete

2009-08-01T23:59:59.000Z

295

An Implicit Algorithm for the Numerical Simulation of Shape-Memory Alloys  

SciTech Connect

Shape-memory alloys (SMA) have the potential to be used in a variety of interesting applications due to their unique properties of pseudoelasticity and the shape-memory effect. However, in order to design SMA devices efficiently, a physics-based constitutive model is required to accurately simulate the behavior of shape-memory alloys. The scope of this work is to extend the numerical capabilities of the SMA constitutive model developed by Jannetti et. al. (2003), to handle large-scale polycrystalline simulations. The constitutive model is implemented within the finite-element software ABAQUS/Standard using a user defined material subroutine, or UMAT. To improve the efficiency of the numerical simulations, so that polycrystalline specimens of shape-memory alloys can be modeled, a fully implicit algorithm has been implemented to integrate the constitutive equations. Using an implicit integration scheme increases the efficiency of the UMAT over the previously implemented explicit integration method by a factor of more than 100 for single crystal simulations.

Becker, R; Stolken, J; Jannetti, C; Bassani, J

2003-10-16T23:59:59.000Z

296

Numerical simulation of a laboratory-scale turbulent V-flame  

SciTech Connect

We present a three-dimensional, time-dependent simulation of a laboratory-scale rod-stabilized premixed turbulent V-flame. The simulations are performed using an adaptive time-dependent low Mach number model with detailed chemical kinetics and a mixture model for differential species diffusion. The algorithm is based on a second-order projection formulation and does not require an explicit subgrid model for turbulence or turbulence chemistry interaction. Adaptive mesh refinement is used to dynamically resolve the flame and turbulent structures. Here, we briefly discuss the numerical procedure and present detailed comparisons with experimental measurements showing that the computation is able to accurately capture the basic flame morphology and associated mean velocity field. Finally, we discuss key issues that arise in performing these types of simulations and the implications of these issues for using computation to form a bridge between turbulent flame experiments and basic combustion chemistry.

Bell, J.B.; Day, M.S.; Shepherd, I.G.; Johnson, M.; Cheng, R.K.; Grcar,J.F.; Beckner, V.E.; Lijewski, M.J.

2005-02-07T23:59:59.000Z

297

Numerical simulation of sloshing in LNG tanks with a compressible two-phase model  

E-Print Network (OSTI)

The study of liquid dynamics in LNG tanks is getting more and more important with the actual trend of LNG tankers sailing with partially filled tanks. The effect of sloshing liquid in the tanks on pressure levels at the tank walls and on the overall ship motion indicates the relevance of an accurate simulation of the fluid behaviour. This paper presents the simulation of sloshing LNG by a compressible two-phase model and the validation of the numerical model on model-scale sloshing experiments. The details of the numerical model, an improved Volume Of Fluid (iVOF) method, are presented in the paper. The program has been developed initially to study the sloshing of liquid fuel in spacecraft. The micro-gravity environment requires a very accurate and robust description of the free surface. Later, the numerical model has been used for calculations for different offshore applications, including green water loading. The model has been extended to take two-phase flow effects into account. These effects are particularly important for sloshing in tanks. The complex mixture of the liquid and gas phase around

Rik Wemmenhove; Arthur E. P. Veldman; Tim Bunnik

2007-01-01T23:59:59.000Z

298

An Efficient Numerical Scheme for Simulating Unidirectional Irregular Waves Based on a Hybrid Wave Model  

E-Print Network (OSTI)

The Unidirectional Hybrid Wave Model (UHWM) predicts irregular wave kinematics and pressure accurately in comparison with its linear counterpart and modification, especially near the free surface. Hence, in using the Morrison equation it has been employed in the computation of wave loads on a moored floating structure, such as Spar or TLP (Tension Leg Platform), which can be approximated by a slender body or a number of slender components. Dr. Jun Zhang, with his former and current graduate students, have developed a numerical code, known as COUPLE, over the past two decades, simulating 6 Degree Of Freedom (DOF) motions of a moored floating structures interacting with waves, current and wind. COUPLE employs UHWM as a module for computing wave loads on a floating structure. However, when the duration of simulating the wave-structure interaction is long, say 3 hours (typically required by the offshore industry for extreme storm cases), the computation time of using UHWM increases significantly in comparisons with the counterpart based upon linear wave theory. This study is to develop a numerical scheme which may significantly reduce the CPU time in the use of UHWM and COUPLE. In simulating irregular (or random) waves following a JONSWAP spectrum of a given cut off frequency, the number of free wave components in general grows linearly with the increase of the simulation duration. The CPU time for using a linear spectral method to simulate irregular waves is roughly proportion to N2, where N is the number of free wave components used in simulating irregular waves, while that for using a nonlinear wave model, such as UHWM, it is roughly proportional to N3. Therefore, to reduce the CPU time, the total simulation duration is divided into a number of segments. However, due to the nature of Fast Fourier Transform (FFT), the connection between the two neighboring surface elevations segments is likely discontinuous. To avoid the discontinuity, an overlapped duration between the two neighboring segments is adopted. For demonstration, a free-wave spectrum is input to COUPLE for simulating the 6 DOF motions of a floating 5-MW wind turbine installed on an OC3 moored Spar and tensions in the mooring lines. It is shown that the CPU time for the above simulation for duration of 2048 seconds is reduced from more than16 hours when the irregular wave elevation and kinematics are calculated without dividing into segments to less than three hours when those are calculated by dividing into five segments.

Jia, Dongxing 1984-

2012-12-01T23:59:59.000Z

299

Experimental measurement and numerical simulation of residual stresses in a carburized layer of a 5120 steel  

Science Conference Proceedings (OSTI)

A combined experimental and numerical study of residual stress and microstructure has been performed for a carburized steel 5120 specimen. Specimens were cut from 5120 steel bar stock, in the shape of hockey pucks and were subsequently carburized and quenched. X-ray diffraction was used to record stress profiles through the case for the martensite and retained austenite on the two flat surfaces oriented up and down during the quench. Layer removal was performed by electropolishing. Rietveld analysis was used to determine the lattice parameters of the phases at each depth varying with both carbon content and stress. The experimental measurements are compared with a numerical simulation of the phase transformation and the metallurgical changes following the carburization and quench. Results am discussed in the context of the microstructure and the role played by the retained austenite in interpretation. In addition the carbon profile obtained from the lattice parameters is compared with profiles measured using burnout.

Rangaswamy, P.; Bourke, M.A.M.; Shipley, J.C.; Goldstone, J.A.

1995-09-01T23:59:59.000Z

300

Numerical simulation of flow distribution for pebble bed high temperature gas cooled reactors  

E-Print Network (OSTI)

The premise of the work presented here is to use a common analytical tool, Computational Fluid dynamics (CFD), along with a difference turbulence models. Eddy viscosity models as well as state-of-the-art Large Eddy Simulation (LES) were used to study the flow past bluff bodies. A suitable CFD code (CFX5.6b) was selected and implemented. Simulation of turbulent transport for the gas through the gaps of the randomly distributed spherical fuel elements (pebbles) was performed. Although there are a number of numerical studies () on flows around spherical bodies, none of them use the necessary turbulence models that are required to simulate flow where strong separation exists. With the development of high performance computers built for applications that require high CPU time and memory; numerical simulation becomes one of the more effective approaches for such investigations and LES type of turbulence models can be used more effectively. Since there are objects that are touching each other in the present study, a special approach was applied at the stage of building computational domain. This is supposed to be a considerable improvement for CFD applications. Zero thickness was achieved between the pebbles in which fission reaction takes place. Since there is a strong pressure gradient as a result of high Reynolds Number on the computational domain, which strongly affects the boundary layer behavior, heat transfer in both laminar and turbulent flows varies noticeably. Therefore, noncircular curved flows as in the pebble-bed situatio n, in detailed local sense, is interesting to be investigated. Since a compromise is needed between accuracy of results and time/cost of effort in acquiring the results numerically, selection of turbulence model should be done carefully. Resolving all the scales of a turbulent flow is too costly, while employing highly empirical turbulence models to complex problems could give inaccurate simulation results. The Large Eddy Simulation (LES) method would achieve the requirements to obtain a reasonable result. In LES, the large scales in the flow are solved and the small scales are modeled. Eddy viscosity and Reynolds stress models were also be used to investigate the applicability of these models for this kind of flow past bluff bodies at high Re numbers.

Yesilyurt, Gokhan

2006-05-01T23:59:59.000Z

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301

Terascale direct numerical simulations of turbulent combustion using S3D.  

DOE Green Energy (OSTI)

Computational science is paramount to the understanding of underlying processes in internal combustion engines of the future that will utilize non-petroleum-based alternative fuels, including carbon-neutral biofuels, and burn in new combustion regimes that will attain high efficiency while minimizing emissions of particulates and nitrogen oxides. Next-generation engines will likely operate at higher pressures, with greater amounts of dilution and utilize alternative fuels that exhibit a wide range of chemical and physical properties. Therefore, there is a significant role for high-fidelity simulations, direct numerical simulations (DNS), specifically designed to capture key turbulence-chemistry interactions in these relatively uncharted combustion regimes, and in particular, that can discriminate the effects of differences in fuel properties. In DNS, all of the relevant turbulence and flame scales are resolved numerically using high-order accurate numerical algorithms. As a consequence terascale DNS are computationally intensive, require massive amounts of computing power and generate tens of terabytes of data. Recent results from terascale DNS of turbulent flames are presented here, illustrating its role in elucidating flame stabilization mechanisms in a lifted turbulent hydrogen/air jet flame in a hot air co-flow, and the flame structure of a fuel-lean turbulent premixed jet flame. Computing at this scale requires close collaborations between computer and combustion scientists to provide optimized scaleable algorithms and software for terascale simulations, efficient collective parallel I/O, tools for volume visualization of multiscale, multivariate data and automating the combustion workflow. The enabling computer science, applied to combustion science, is also required in many other terascale physics and engineering simulations. In particular, performance monitoring is used to identify the performance of key kernels in the DNS code, S3D and especially memory intensive loops in the code. Through the careful application of loop transformations, data reuse in cache is exploited thereby reducing memory bandwidth needs, and hence, improving S3D's nodal performance. To enhance collective parallel I/O in S3D, an MPI-I/O caching design is used to construct a two-stage write-behind method for improving the performance of write-only operations. The simulations generate tens of terabytes of data requiring analysis. Interactive exploration of the simulation data is enabled by multivariate time-varying volume visualization. The visualization highlights spatial and temporal correlations between multiple reactive scalar fields using an intuitive user interface based on parallel coordinates and time histogram. Finally, an automated combustion workflow is designed using Kepler to manage large-scale data movement, data morphing, and archival and to provide a graphical display of run-time diagnostics.

Sankaran, Ramanan; Mellor-Crummy, J.; DeVries, M.; Yoo, Chun Sang; Ma, K. L.; Podhorski, N.; Liao, W. K.; Klasky, S.; de Supinski, B.; Choudhary, A.; Hawkes, Evatt R.; Chen, Jacqueline H.; Shende, Sameer

2008-08-01T23:59:59.000Z

302

Direct Numerical Simulation of Electrokinetic Instability and Transition to Chaotic Motion  

E-Print Network (OSTI)

A new type of instability - electrokinetic instability - and an unusual transition to chaotic motion near a charge-selective surface was studied by numerical integration of the Nernst-Planck-Poisson-Stokes system and a weakly nonlinear analysis near the threshold of instability. Two kinds of initial conditions were considered: (a) white noise initial conditions to mimic "room disturbances" and subsequent natural evolution of the solution; (b) an artificial monochromatic ion distribution with a fixed wave number to simulate regular wave patterns. The results were studied from the viewpoint of hydrodynamic stability and bifurcation theory. The threshold of electroconvective movement was found by the linear spectral stability theory, the results of which were confirmed by numerical simulation of the entire system. The following regimes, which replace each other as the potential drop between the selective surfaces increases, were obtained: one-dimensional steady solution; two-dimensional steady electroconvective vortices (stationary point in a proper phase space); unsteady vortices aperiodically changing their parameters (homoclinic contour); periodic motion (limit cycle); and chaotic motion. The transition to chaotic motion did not include Hopf bifurcation. Numerical resolution of the thin concentration polarization layer showed spike-like charge profiles along the surface, which could be, depending on the regime, either steady or aperiodically coalescent. The numerical investigation confirmed the experimentally observed absence of regular (near-sinusoidal) oscillations for the overlimiting regimes. There is a qualitative agreement of the experimental and the theoretical values of the threshold of instability, the dominant size of the observed coherent structures, and the experimental and theoretical volt-current characteristics.

E. A. Demekhin; N. V. Nikitin; V. S. Shelistov

2013-06-18T23:59:59.000Z

303

Analysis and numerical simulation of a laboratory analog of radiatively induced cloud-top entrainment.  

Science Conference Proceedings (OSTI)

Numerical simulations using the One-Dimensional-Turbulence model are compared to water-tank measurements [B. J. Sayler and R. E. Breidenthal, J. Geophys. Res. 103 (D8), 8827 (1998)] emulating convection and entrainment in stratiform clouds driven by cloud-top cooling. Measured dependences of the entrainment rate on Richardson number, molecular transport coefficients, and other experimental parameters are reproduced. Additional parameter variations suggest more complicated dependences of the entrainment rate than previously anticipated. A simple algebraic model indicates the ways in which laboratory and cloud entrainment behaviors might be similar and different.

Kerstein, Alan R.; Sayler, Bentley J. (Black Hills State University); Wunsch, Scott Edward (Johns Hopkins University); Schmidt, Heiko (Tech. University Cottbus); Nedelec, Renaud (Ecole Centrale Marseille)

2010-11-01T23:59:59.000Z

304

Experiments and Direct Numerical Simulations of binary collisions of miscible liquid droplets with different viscosities  

E-Print Network (OSTI)

Binary droplet collisions are of importance in a variety of practical applications comprising dispersed two-phase flows. The background of our research is the prediction of properties of particulate products formed in spray processes. To gain a more thorough understanding of the elementary sub-processes inside a spray, experiments and direct numerical simulations of binary droplet collisions are used. The aim of these investigations is to develop semi-analytical descriptions for the outcome of droplet collisions. Such collision models can then be employed as closure terms for scale-reduced simulations. In the present work we focus on the collision of droplets of different liquids. These kinds of collisions take place in every spray drying process when droplets with different solids contents collide in recirculation zones. A new experimental method has been developed allowing for high spatial and time resolved recordings via Laser-induced fluorescence. The results obtained with the proposed method will be comp...

Focke, C

2012-01-01T23:59:59.000Z

305

Numerical simulation of the pre-ionization processes during nanosecond-pulse discharge in nitrogen  

Science Conference Proceedings (OSTI)

The pre-ionization of nitrogen gas by high-voltage nanosecond pulse discharges is studied using one-dimensional particle-in-cell numerical simulations. The comparison between the various mechanisms of pre-ionization, i.e., by runaway electrons, x-rays, and ultraviolet radiation, is presented. It is shown that runaway electrons produce a much higher number of electron-ion pairs than those generated by x-rays, which accompany the process of runaway electron generation. Also, results of simulations showed that among photo-ionization mechanisms the most significant gas pre-ionization is caused by x-rays generated in the process of impact ionization of the K-shell of nitrogen atoms.

Levko, D.; Gurovich, V. Tz.; Krasik, Ya. E.

2012-01-01T23:59:59.000Z

306

Direct numerical simulation of temporally evolving luminous jet flames with detailed fuel and soot chemistry  

Science Conference Proceedings (OSTI)

Direct numerical simulations of 2D temporally-evolving luminous turbulent ethylene-air jet diffusion flames are performed using a high-order compressible Navier-Stokes solver. The simulations use a reduced mechanism derived from a detailed ethylene-air chemical kinetic mechanism that includes the reaction pathways for the formation of polycyclic aromatic hydrocarbons. The gas-phase chemistry is coupled with a detailed soot particle model based on the method of moments with interpolative closure that accounts for soot nucleation, coagulation, surface growth through HACA mechanism, and oxidation. Radiative heat transfer of CO{sub 2}, H{sub 2}O, and soot is treated by solving the radiative transfer equation using the discrete transfer method. This work presents preliminary results of radiation effects on soot dynamics at the tip of a jet diffusion flame with a particular focus on soot formation/oxidation.

Sankaran, Ramanan [ORNL

2011-01-01T23:59:59.000Z

307

Numerical Simulations of the Subsynoptic Features Associated with the AVE-SESAME I Case. Part I: The Preconvective Environment  

Science Conference Proceedings (OSTI)

A series of mesoscale numerical simulations of the AVE-SESAME I case (10 April 1979) were performed in order to analyze the dynamical processes that result in the production of an environment favorable for the development of severe local ...

John W. Zack; Michael L. Kaplan

1987-10-01T23:59:59.000Z

308

A Model Comparison: Numerical Simulations of the North and Equatorial Atlantic Oceanic Circulation in Depth and Isopycnic Coordinates  

Science Conference Proceedings (OSTI)

A series of medium-resolution (1) numerical simulations for the equatorial and North Atlantic basin have been performed with two primitive equation models, one employing depth and the other density as the vertical coordinate. The models have ...

Eric P. Chassignet; Linda T. Smith; Rainer Bleck; Frank O. Bryan

1996-09-01T23:59:59.000Z

309

Electrification of Stratiform Regions in Mesoscale Convective Systems. Part II: Two-Dimensional Numerical Model Simulations of a Symmetric MCS  

Science Conference Proceedings (OSTI)

Model simulations of a symmetric mesoscale convective system (MCS; observations discussed in Part I) were conducted using a 2D, time-dependent numerical model with bulk microphysics. A number of charging mechanisms were considered based on ...

Terry J. Schuur; Steven A. Rutledge

2000-07-01T23:59:59.000Z

310

Numerical Simulations of Outdoor Heat Stress Index and Heat Disorder Risk in the 23 Wards of Tokyo  

Science Conference Proceedings (OSTI)

In the present study, the summertime outdoor heat stress hazard and heat disorder risks (HDRs) were simulated numerically using a mesoscale meteorological model combined with an urban canopy model and a building energy model. Model grid maps ...

Yukitaka OHASHI; Yukihiro KIKEGAWA; Tomohiko IHARA; Nanami SUGIYAMA

311

Numerical Simulations of Buoyant Ekman Layers in the Presence of Variable Stratification. Part I: Constant Interior Forcing  

Science Conference Proceedings (OSTI)

Two-dimensional numerical simulations of the turbulent buoyant Ekman layer in the presence of variable stratification help explain a transport mechanism for the detachment of the boundary layer flow around the front. Initially, a constant, ...

A. Romanou; G. L. Weatherly

2001-10-01T23:59:59.000Z

312

The Numerical Simulation of Drainage Winds in a Small Urban Valley under Conditions with Supercritical Richardson Numbers  

Science Conference Proceedings (OSTI)

A two-dimensional numerical model is used to simulate nocturnal drainage flow in a small urban valley with light prevailing winds and conditions of supercritical Richardson numbers (Ri). The model uses a hydrostatic and Boussinesq system of ...

Raymond K. W. Wong; Keith D. Hage; Leslie D. Phillips

1987-10-01T23:59:59.000Z

313

Numerical Simulations of the Postsunrise Reorganization of a Nocturnal Mesoscale Convective System during 13 June IHOP_2002  

Science Conference Proceedings (OSTI)

A convection-permitting numerical model is used to simulate the postsunrise reorganization of a nocturnal mesoscale convective system (MCS) observed over western and central Oklahoma on 13 June 2002 during the International H2O (IHOP_2002) Field ...

Stanley B. Trier; John H. Marsham; Christopher A. Davis; David A. Ahijevych

2011-12-01T23:59:59.000Z

314

The Meridional Flow of Source-Driven Abyssal Currents in a Stratified Basin with Topography. Part II: Numerical Simulation  

Science Conference Proceedings (OSTI)

A numerical simulation is described for source-driven abyssal currents in a 3660 km 3660 km stratified Northern Hemisphere basin with zonally varying topography. The model is the two-layer quasigeostrophic equations, describing the overlying ...

Gordon E. Swaters

2006-03-01T23:59:59.000Z

315

Effects of Surface Exchange Coefficients and Turbulence Length Scales on the Intensity and Structure of Numerically Simulated Hurricanes  

Science Conference Proceedings (OSTI)

Using numerical simulations, this study examines the sensitivity of hurricane intensity and structure to changes in the surface exchange coefficients and to changes in the length scales of a turbulence parameterization. Compared to other recent ...

George H. Bryan

2012-04-01T23:59:59.000Z

316

Numerical Simulations of the Effects of Coastlines on the Evolution of Strong, Long-Lived Squall Lines  

Science Conference Proceedings (OSTI)

This study develops conceptual models of how a landwater interface affects the strength and structure of squall lines. Two-dimensional numerical simulations using the Advanced Regional Prediction System model are employed. Five sets of ...

Todd P. Lericos; Henry E. Fuelberg; Morris L. Weisman; Andrew I. Watson

2007-05-01T23:59:59.000Z

317

The Instability of Long's Stationary Solution and the Evolution toward Severe Downslope Windstorm Flow. Part I: Nested Grid Numerical Simulations  

Science Conference Proceedings (OSTI)

Through direct numerical simulation, the instability of Long's exact finite-amplitude steady-state solution to the problem of stratified flow over topography and the subsequent evolution towards severe downslope windstorm flow is investigated. ...

J. F. Scinocca; W. R. Peltier

1993-07-01T23:59:59.000Z

318

The Influence of Horizontal Environmental Variability on Numerically Simulated Convective Storms. Part I: Variations in Vertical Shear  

Science Conference Proceedings (OSTI)

Severe convective storms are typically simulated using either an idealized, horizontally homogeneous environment (i.e., single sounding) or an inhomogeneous environment constructed using numerous types of observations. Representing opposite ends ...

Yvette P. Richardson; Kelvin K. Droegemeier; Robert P. Davies-Jones

2007-10-01T23:59:59.000Z

319

Sensor and numerical simulator evaluation for porous medium desiccation and rewetting at the intermediate laboratory scale  

Science Conference Proceedings (OSTI)

Soil desiccation, in conjunction with surface infiltration control, is considered at the Hanford Site as a potential technology to limit the flux of technetium and other contaminants in the vadose zone to the groundwater. An intermediate-scale experiment was conducted to test the response of a series of instruments to desiccation and subsequent rewetting of porous media. The instruments include thermistors, thermocouple psychrometers, dual-probe heat pulse sensors, heat dissipation units, and humidity probes. The experiment was simulated with the multifluid flow simulator STOMP, using independently obtained hydraulic and thermal porous medium properties. All instrument types used for this experiment were able to indicate when the desiccation front passed a certain location. In most cases the changes were sharp, indicating rapid changes in moisture content, water potential, or humidity. However, a response to the changing conditions was recorded only when the drying front was very close to a sensor. Of the tested instruments, only the heat dissipation unit and humidity probes were able to detect rewetting. The numerical simulation results reasonably match the experimental data, indicating that the simulator captures the pertinent gas flow and transport processes related to desiccation and rewetting and may be useful in the design and analysis of field tests.

Oostrom, Martinus; Wietsma, Thomas W.; Strickland, Christopher E.; Freedman, Vicky L.; Truex, Michael J.

2012-02-01T23:59:59.000Z

320

Higher order discretization methods for the numerical simulation of fluidized beds  

SciTech Connect

Numerical models of fluidized beds based on the multiphase mass and momentum balance equations for gas and solids phases continue to be developed by several groups of researchers around the world. It has been demonstrated that the same set of equations is able to describe a wide range of fluidization conditions, ranging from bubbling to circulating fluidized beds. The results of bubbling bed simulations, plots of void fraction distribution, show the formation and propagation of high void fraction regions, called bubbles. This study shows that these problems are numerical artifacts of using first order accurate discretization schemes and coarse grids and are not due to a fundamental difficulty with the theory. This study was motivated by the observation that the shape of the gas hold up profile described by Sokolichin et al. is similar to that of the shape of bubbles in a fluidized bed. Second-order accurate discretization schemes were included in a multiphase flow model of fluidized beds called MFIX. It is shown here that the bubble shape predicted with a second order accurate scheme is rounded. The simulations were conducted for long durations (5 s) and the results did not show the fountain formation at the bed surface. It appears that the fountain formation is caused by coarse grids and low physical viscosity of the solids phase.

Syamlal, M.

1997-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Comparison of chemical and nuclear explosions: Numerical simulations of the Non-Proliferation Experiment  

SciTech Connect

In this paper the authors discuss numerical simulations of the Non-Proliferation Experiment (NPE), which was an underground explosion conducted in September 1993 in the volcanic tuff of the Nevada Test Site. The NPE source consisted of 1.29 {times} 10{sup 6} kg of ANFO-emulsion blasting agent, with the approximate energy of 1.1 kt, emplaced 389 m beneath the surface of Rainier Mesa. The authors compare detailed numerical simulations of the NPE with data collected from that experiment, and with calculations of an equally energetic nuclear explosion in identical geology. Calculated waveforms, at ranges out to approximately 1 km, agree moderately well in the time domain with free-field data, and are in qualitative agreement with free-surface records. Comparison of computed waveforms for equally energetic chemical and nuclear sources reveals relatively minor differences beyond the immediate near-source region, with the chemical source having an {approximately}25% greater seismic moment but otherwise indistinguishable (close-in) seismic source properties. 41 refs., 67 figs., 7 tabs.

Kamm, J.R.; Bos, R.J.

1995-06-01T23:59:59.000Z

322

CO2-Driven Enhanced Gas Recovery and Storage in Depleted Shale Reservoir-A Numerical Simulation Study  

E-Print Network (OSTI)

1 CO2-Driven Enhanced Gas Recovery and Storage in Depleted Shale Reservoir- A Numerical Simulation for storage and enhanced gas recovery may be organic-rich shales, which CO2 is preferentially adsorbed comprehensive simulation studies to better understand CO2 injection process in shale gas reservoir. This paper

Mohaghegh, Shahab

323

Vortex Rossby Waves in a Numerically Simulated Tropical Cyclone. Part I: Overall Structure, Potential Vorticity, and Kinetic Energy Budgets  

Science Conference Proceedings (OSTI)

The asymmetric structure in the inner core of a numerically simulated tropical cyclone is analyzed in this study. The simulated tropical cyclone is found to be highly asymmetric in the inner core. In the midlower troposphere, the asymmetry in ...

Yuqing Wang

2002-04-01T23:59:59.000Z

324

Forecasting Gas Production in Organic Shale with the Combined Numerical Simulation of Gas Diffusion in Kerogen, Langmuir Desorption from  

E-Print Network (OSTI)

SPE 159250 Forecasting Gas Production in Organic Shale with the Combined Numerical Simulation algorithm to forecast gas production in organic shale that simultaneously takes into account gas diffusion-than-expected permeability in shale-gas formations, while Langmuir desorption maintains pore pressure. Simulations confirm

Torres-Verdín, Carlos

325

Numerical simulation to determine the effects of incident wind shear and turbulence level on the flow around a building  

Science Conference Proceedings (OSTI)

The effects of incident shear and turbulence on flow around a cubical building are being investigated by a turbulent kinetic energy/dissipation model (TEMPEST). The numerical simulations demonstrate significant effects due to the differences in the incident flow. The addition of upstream turbulence and shear results in a reduced size of the cavity directly behind the building. The accuracy of numerical simulations is verified by comparing the predicted mean flow fields with the available wind-tunnel measurements of Castro and Robins (1977). Comparing the authors' results with experimental data, the authors show that the TEMPEST model can reasonably simulate the mean flow.

Zhang, Y.Q.; Huber, A.H.; Arya, S.P.S.; Snyder, W.H.

1992-01-01T23:59:59.000Z

326

Three-dimensional numerical simulations of Rayleigh-Taylorunstable flames in type Ia supernovae  

SciTech Connect

Flame instabilities play a dominant role in accelerating the burning front to a large fraction of the speed of sound in a Type Ia supernova. We present a three-dimensional numerical simulation of a Rayleigh-Taylor unstable carbon flame, following its evolution through the transition to turbulence. A low Mach number hydrodynamics method is used, freeing us from the harsh time step restrictions imposed by sound waves. We fully resolve the thermal structure of the flame and its reaction zone, eliminating the need for a flame model. A single density is considered, 1.5x107 gm/cc, and half carbon/half oxygen fuel--conditions under which the flame propagated in the flamelet regime in our related two-dimensional study. We compare to a corresponding two-dimensional simulation, and show that while fire-polishing keeps the small features suppressed in two dimensions, turbulence wrinkles the flame on far smaller scales in the three-dimensional case, suggesting that the transition to the distributed burning regime occurs at higher densities in three dimensions. Detailed turbulence diagnostics are provided. We show that the turbulence follows a Kolmogorov spectrum and is highly anisotropic on the large scales, with a much larger integral scale in the direction of gravity. Furthermore, we demonstrate that it becomes more isotropic as it cascades down to small scales. Based on the turbulent statistics and the flame properties of our simulation, we compute the Gibson scale. We show the progress of the turbulent flame through a classic combustion regime diagram, indicating that the flame just enters the distributed burning regime near the end of our simulation.

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

2005-01-28T23:59:59.000Z

327

Enhanced Remedial Amendment Delivery through Fluid Viscosity Modifications: Experiments and numerical simulations  

SciTech Connect

Abstract Heterogeneity is often encountered in subsurface contamination characterization and remediation. Low-permeability zones are typically bypassed when remedial fluids are injected into subsurface heterogeneous aquifer systems. Therefore, contaminants in the bypassed areas may not be contacted by the amendments in the remedial fluid, which may significantly prolong the remediation operations. Laboratory experiments and numerical studies have been conducted to develop the Mobility-Controlled Flood (MCF) technology for subsurface remediation and to demonstrate the capability of this technology in enhancing the remedial amendments delivery to the lower permeability zones in heterogeneous systems. Xanthan gum, a bio-polymer, was used to modify the viscosity of the amendment-containing remedial solutions. Sodium mono-phosphate and surfactant were the remedial amendment used in this work. The enhanced delivery of the amendments was demonstrated in two-dimensional (2-D) flow cell experiments, packed with heterogeneous systems. The impact of polymer concentration, fluid injection rate, and permeability contract in the heterogeneous systems has been studied. The Subsurface Transport over Multiple Phases (STOMP) simulator was modified to include polymer-induced shear thinning effects. Shear rates of polymer solutions were computed from pore-water velocities using a relationship proposed in the literature. Viscosity data were subsequently obtained from empirical viscosity-shear rate relationships derived from laboratory data. The experimental and simulation results clearly show that the MCF technology is capable of enhancing the delivery of remedial amendments to subsurface lower permeability zones. The enhanced delivery significantly improved the NAPL removal from these zones and the sweeping efficiency on a heterogeneous system was remarkably increased when a polymer fluid was applied. MCF technology is also able to stabilize the fluid displacing front when there is a density difference between the fluids. The modified STOMP simulator was able to predict the experimental observed fluid displacing behavior. The simulator may be used to predict the subsurface remediation performance when a shear thinning fluid is used to remediate a heterogeneous system.

Zhong, Lirong; Oostrom, Martinus; Wietsma, Thomas W.; Covert, Matthew A.

2008-07-29T23:59:59.000Z

328

Numerical Simulations of Wire and Foil Behaviors under Megaampere Current Drive *  

National Nuclear Security Administration (NNSA)

2: High Energy Density, Plasmas, Magnetic Fields 2: High Energy Density, Plasmas, Magnetic Fields Numerical Simulations of Wire and Foil Electrical Explosion under Helical EMG Current Drive for Warm Dense Matter Generation S.F. Garanin*, A.M. Buyko*, S.D. Kuznetsov*, R.E. Reinovsky† * Russian Federal Nuclear Center - VNIIEF Sarov, 607190, Russia † Los Alamos National Laboratory, Los Alamos, NM 87545 USA Study of properties of Warm Dense Matter (WDM), i. e. substance at densities of the order of that of solids (from 10 % normal density to 2-3 times solid density) and moderate temperatures (1-10 eV), is in recent times an active field of investigations. Experiments to study electrical explosion of thick wires (0.5-2 mm in diameter) driven by currents of about 1 MA were conducted recently [1] on the Zebra facility at the University of Nevada, Reno. The

329

TOUGH2: A general-purpose numerical simulator for multiphase fluid and heat flow  

DOE Green Energy (OSTI)

TOUGH2 is a numerical simulation program for nonisothermal flows of multicomponent, multiphase fluids in porous and fractured media. The chief applications for which TOUGH2 is designed are in geothermal reservoir engineering, nuclear waste disposal, and unsaturated zone hydrology. A successor to the TOUGH program, TOUGH2 offers added capabilities and user features, including the flexibility to handle different fluid mixtures, facilities for processing of geometric data (computational grids), and an internal version control system to ensure referenceability of code applications. This report includes a detailed description of governing equations, program architecture, and user features. Enhancements in data inputs relative to TOUGH are described, and a number of sample problems are given to illustrate code applications. 46 refs., 29 figs., 12 tabs.

Pruess, K.

1991-05-01T23:59:59.000Z

330

A high-order public domain code for direct numerical simulations of turbulent combustion  

E-Print Network (OSTI)

A high-order scheme for direct numerical simulations of turbulent combustion is discussed. Its implementation in the massively parallel and publicly available Pencil Code is validated with the focus on hydrogen combustion. Ignition delay times (0D) and laminar flame velocities (1D) are calculated and compared with results from the commercially available Chemkin code. The scheme is verified to be fifth order in space. Upon doubling the resolution, a 32-fold increase in the accuracy of the flame front is demonstrated. Finally, also turbulent and spherical flame front velocities are calculated and the implementation of the non-reflecting so-called Navier-Stokes Characteristic Boundary Condition is validated in all three directions.

Babkovskaia, N; Brandenburg, A

2010-01-01T23:59:59.000Z

331

Studying the Imaging Characteristics of Ultra Violet Imaging Telescope (UVIT) through Numerical Simulations  

E-Print Network (OSTI)

Ultra-Violet Imaging Telescope (UVIT) is one of the five payloads aboard the Indian Space Research Organization (ISRO)'s ASTROSAT space mission. The science objectives of UVIT are broad, extending from individual hot stars, star-forming regions to active galactic nuclei. Imaging performance of UVIT would depend on several factors in addition to the optics, e.g. resolution of the detectors, Satellite Drift and Jitter, image frame acquisition rate, sky background, source intensity etc. The use of intensified CMOS-imager based photon counting detectors in UVIT put their own complexity over reconstruction of the images. All these factors could lead to several systematic effects in the reconstructed images. A study has been done through numerical simulations with artificial point sources and archival image of a galaxy from GALEX data archive, to explore the effects of all the above mentioned parameters on the reconstructed images. In particular the issues of angular resolution, photometric accuracy and photometric...

Srivastava, Mudit K; Tandon, Shyam N

2009-01-01T23:59:59.000Z

332

Numerical simulation of transient gas flow during underbalanced drilling into a gas sand  

Science Conference Proceedings (OSTI)

Shallow gas drilling has long been recognized as a serious problem in offshore operations. Low fracture gradients and shallow casing do not permit shutting- in the well. Computer simulations of gas kicks during drilling require accurate description of the gas flow rate from the formation into the wellbore. The problem is complicated by the fact that during drilling into a gas sand the effective wellbore area exposed to flow is continually changing until the formation has been completely drilled. This paper describes a numerical model developed to calculate gas flow into the wellbore while drilling underbalanced into a gas sand. A two-dimensional finite difference model of transient flow from the reservoir has been coupled with a one-dimensional finite element model of two-phase flow in the wellbore.

Berg, K.A.; Skalle, P. (Dept. of Petroleum Engineering, Univ. of Trondheim (NO)); Podio, A.L. (Dept. of Petroleum Engineering, Univ. of Texas at Austin, Austin, TX (US))

1991-01-01T23:59:59.000Z

333

Numerical Simulation of Annealing of CdSe Quantum Dots for White Light LEDs  

Science Conference Proceedings (OSTI)

The pulsed thermal processing (PTP) of CdSe Quantum Dots (QD) using a High Density plasma arc lamp. The single layer of CdSe QD was deposited on sapphire and was encapsulated in an alumina matrix. A computational methodology is proposed to understand the energy transport and annealing of QD material for solid-state lighting applications. It was found that the energy balance in the system was affected by the QD. The QD monolayer of spheres was found to alter the total reflectivity, even though the energy absorbed in QD was relatively small. The numerical simulations can be an effective tool to predict the narrow range of processing parameters and dramatically reduce expensive trial-and-error procedures while enabling the enhanced properties of nanostructured materials to be realized.

Sabau, Adrian S [ORNL; Duty, Chad E [ORNL; Ott, Ronald D [ORNL; Jellison Jr, Gerald Earle [ORNL

2008-01-01T23:59:59.000Z

334

THREE-DIMENSIONAL NUMERICAL SIMULATIONS OF FAST-TO-ALFVEN CONVERSION IN SUNSPOTS  

SciTech Connect

The conversion of fast waves to the Alfven mode in a realistic sunspot atmosphere is studied through three-dimensional numerical simulations. An upward propagating fast acoustic wave is excited in the high-{beta} region of the model. The new wave modes generated at the conversion layer are analyzed from the projections of the velocity and magnetic field in their characteristic directions, and the computation of their wave energy and fluxes. The analysis reveals that the maximum efficiency of the conversion to the slow mode is obtained for inclinations of 25 Degree-Sign and low azimuths, while the Alfven wave conversions peak at high inclinations and azimuths between 50 Degree-Sign and 120 Degree-Sign . Downward propagating Alfven waves appear at the regions of the sunspot where the orientation of the magnetic field is in the direction opposite to the wave propagation, since at these locations the Alfven wave couples better with the downgoing fast magnetic wave which is reflected due to the gradients of the Alfven speed. The simulations show that the Alfven energy at the chromosphere is comparable to the acoustic energy of the slow mode, being even higher at high inclined magnetic fields.

Felipe, T., E-mail: tobias@cora.nwra.com [NorthWest Research Associates, Colorado Research Associates, Boulder, CO 80301 (United States)

2012-10-20T23:59:59.000Z

335

Terascale Direct Numerical Simulations of Turbulent Combustion: Capabilities and Limits (PReSS Talk)  

DOE Green Energy (OSTI)

The rapid growth in computational capabilities has provided great opportunities for direct numerical simulations (DNS) of turbulent combustion, a type of simulations without any turbulence model. With the help of terascale high performance supercomputing (HPC) resources, we are now able to provide fundamental insight into turbulence-chemistry interaction in simple laboratory-scale turbulent flames with detailed chemistry using three-dimensional (3D) DNS. However, the actual domain size of 3D-DNS is still limited within {approx} O(10 cm{sup 3}) due to its tremendously high grid resolution required to resolve the smallest turbulent length scale as well as flame structures. Moreover, 3D-DNS will require more computing powers to investigate next-generation engines, of which operating conditions will be characterized by higher pressures, lower temperatures, and higher levels of dilution. In this talk, I will discuss the capabilities and limits of DNS of turbulent combustion and present some results of ignition/extinction characteristics of a highly diluted hydrogen flame counter-flowing against heated air. The results of our recent 3D-DNS of a spatially-developing turbulent lifted hydrogen jet flame in heated coflow will also be presented. The 3D-DNS was performed at a jet Reynolds number of 11,000 with {approx} 1 billion grid points, which required 3.5 million CPU hours on Cray XT3/XT4 at Oak Ridge National Laboratories.

Yoo, Chun Sang (Combustion Research Facility, SNL)

2009-03-26T23:59:59.000Z

336

Numerical simulation of jet mixing concepts in Tank 241-SY-101  

SciTech Connect

The episodic gas release events (GRES) that have characterized the behavior of Tank 241-SY-101 for the past several years are thought to result from gases generated by the waste material in it that become trapped in the layer of settled solids at the bottom of the tank. Several concepts for mitigating the GREs have been proposed. One concept involves mobilizing the solid particles with mixing jets. The rationale behind this idea is to prevent formation of a consolidated layer of settled solids at the bottom of the tank, thus inhibiting the accumulation of gas bubbles in this layer. Numerical simulations were conducted using the TEMPEST computer code to assess the viability and effectiveness of the proposed jet discharge concepts and operating parameters. Before these parametric studies were commenced, a series of turbulent jet studies were conducted that established the adequacy of the TEMPEST code for this application. Configurations studied for Tank 241-SY-101 include centrally located downward discharging jets, draft tubes, and horizontal jets that are either stationary or rotating. Parameter studies included varying the jet discharge velocity, jet diameter, discharge elevation, and material properties. A total of 18 simulations were conducted and are reported in this document. The effect of gas bubbles on the mixing dynamics was not included within the scope of this study.

Trent, D.S.; Michener, T.E.

1993-03-01T23:59:59.000Z

337

Direct numerical simulations and hydrodynamic stability problems in the upper oceanic mixed layer  

Science Conference Proceedings (OSTI)

Langmuir circulations are longitudinal rolls driven by the wind and appear beneath the surface of the ocean. The author models these as an instability of the mean current due to its interaction with averaged effect of the surface waves. Perturbations are allowed for in three dimensions for a layer of finite depth. Linear stability analysis shows that two-dimensional rolls are most unstable for unstratified flow as in previous two-dimensional studies. In presence of stratification three-dimensional modes are most unstable. At low and high values of the Reynolds number, the most unstable modes are nearly two-dimensional. At intermediate values, three dimensionality is important. The angular deviation from the wind direction of the most unstable modes increases with stratification in the range considered. Two-dimensional simulations are done at different values of stratification for unconstrained and constrained sidewall boundary conditions. These show good agreement qualitatively and quantitatively with the weakly nonlinear dynamics of the governing equations in two-dimensions. A secondary stability (Floquet) analysis is performed to determine the range of stability of unstratified steady Langmuir rolls and elicit the streamwise length scales when rolls become unstable. Eckhaus and Oscillatory mechanisms of instability are found to be important at a moderate value of Reynolds number. Subsequent direct numerical simulations are performed for corresponding instabilities. Oscillatory instability sets in as streamwise traveling waves. As one of the destabilizing parameters is increased, quasi-periodic motion is observed, with a low frequency vacillating mode. At lower values of Reynolds number, the secondary instability thresholds for the forcing are higher and steady rolls are stable in a large domain of parameter space. Simulations at high forcing at low Reynolds number show defect traveling wave solutions.

Tandon, A.

1992-01-01T23:59:59.000Z

338

Numerical simulations of granular dynamics II. Particle dynamics in a shaken granular material  

E-Print Network (OSTI)

Surfaces of planets and small bodies of our Solar System are often covered by a layer of granular material that can range from a fine regolith to a gravel-like structure of varying depths. Therefore, the dynamics of granular materials are involved in many events occurring during planetary and small-body evolution thus contributing to their geological properties. We demonstrate that the new adaptation of the parallel N-body hard-sphere code pkdgrav has the capability to model accurately the key features of the collective motion of bidisperse granular materials in a dense regime as a result of shaking. As a stringent test of the numerical code we investigate the complex collective ordering and motion of granular material by direct comparison with laboratory experiments. We demonstrate that, as experimentally observed, the scale of the collective motion increases with increasing small-particle additive concentration. We then extend our investigations to assess how self-gravity and external gravity affect collective motion. In our reduced-gravity simulations both the gravitational conditions and the frequency of the vibrations roughly match the conditions on asteroids subjected to seismic shaking, though real regolith is likely to be much more heterogeneous and less ordered than in our idealised simulations. We also show that collective motion can occur in a granular material under a wide range of inter-particle gravity conditions and in the absence of an external gravitational field. These investigations demonstrate the great interest of being able to simulate conditions that are to relevant planetary science yet unreachable by Earth-based laboratory experiments.

Naomi Murdoch; Patrick Michel; Derek C. Richardson; Kerstin Nordstrom; Christian R. Berardi; Simon F. Green; Wolfgang Losert

2013-06-07T23:59:59.000Z

339

Development of a numerical computer code and circuit element models for simulation of firing systems  

SciTech Connect

Numerical simulation of firing systems requires both the appropriate circuit analysis framework and the special element models required by the application. We have modified the SPICE circuit analysis code (version 2G.6), developed originally at the Electronic Research Laboratory of the University of California, Berkeley, to allow it to be used on MSDOS-based, personal computers and to give it two additional circuit elements needed by firing systems--fuses and saturating inductances. An interactive editor and a batch driver have been written to ease the use of the SPICE program by system designers, and the interactive graphical post processor, NUTMEG, supplied by U. C. Berkeley with SPICE version 3B1, has been interfaced to the output from the modified SPICE. Documentation and installation aids have been provided to make the total software system accessible to PC users. Sample problems show that the resulting code is in agreement with the FIRESET code on which the fuse model was based (with some modifications to the dynamics of scaling fuse parameters). In order to allow for more complex simulations of firing systems, studies have been made of additional special circuit elements--switches and ferrite cored inductances. A simple switch model has been investigated which promises to give at least a first approximation to the physical effects of a non ideal switch, and which can be added to the existing SPICE circuits without changing the SPICE code itself. The effect of fast rise time pulses on ferrites has been studied experimentally in order to provide a base for future modeling and incorporation of the dynamic effects of changes in core magnetization into the SPICE code. This report contains detailed accounts of the work on these topics performed during the period it covers, and has appendices listing all source code written documentation produced.

Carpenter, K.H. (Kansas State Univ., Manhattan, KS (USA). Dept. of Electrical and Computer Engineering)

1990-07-02T23:59:59.000Z

340

Numerical simulation of VAWT stochastic aerodynamic loads produced by atmospheric turbauence: VAWT-SAL code  

DOE Green Energy (OSTI)

Blade fatigue life is an important element in determining the economic viability of the Vertical-Axis Wind Turbine (VAWT). A principal source of blade fatigue is thought to be the stochastic (i.e., random) aerodynamic loads created by atmospheric turbulence. This report describes the theoretical background of the VAWT Stochastic Aerodynamic Loads (VAWT-SAL) computer code, whose purpose is to numerically simulate these random loads, given the rotor geometry, operating conditions, and assumed turbulence properties. A Double-Multiple-Stream Tube (DMST) analysis is employed to model the rotor's aerodynamic response. The analysis includes the effects of Reynolds number variations, different airfoil sections and chord lengths along the blade span, and an empirical model for dynamic stall effects. The mean ambient wind is assumed to have a shear profile which is described by either a power law or a logarithmic variation with height above ground. Superimposed on this is a full 3-D field of turbulence: i.e., in addition to random fluctuations in time, the turbulence is allowed to vary randomly in planes perpendicular to the mean wind. The influence of flow retardation on the convection of turbulence through the turbine is also modeled. Calculations are presented for the VAWT 34-m Test Bed currently in operation at Bushland, Texas. Predicted time histories of the loads, as well as their Fourier spectra, are presented and discussed. Particular emphasis is placed on the differences between so-called steady-state'' (mean wind only) predictions, and those produced with turbulence present. Somewhat surprisingly, turbulence is found to be capable of either increasing or decreasing the average output power, depending on the turbine's tip-speed ratio. A heuristic explanation for such behavior is postulated, and a simple formula is derived for predicting the magnitude of this effect without the need for a full stochastic simulation. 41 refs., 32 figs., 1 tab.

Homicz, G.F.

1991-09-01T23:59:59.000Z

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341

Numerical simulations for width fluctuations in compound elastic and inelastic scattering at low energies  

SciTech Connect

The statistical theories - the Hauser-Feshbach model with the width fluctuation correction - play a central role in studying nuclear reactions in the fast energy region, hence the statistical model codes are essential for the nuclear data evaluations nowadays. In this paper, we revisit issues regarding the statistical model calculations in the fast energy range, such as the inclusion of the direct channels, and the energy averaged cross sections using different statistical assumptions. Although they have been discussed for a long time, we need more precise quantitative investigations to understand uncertainties coming from the models deficiencies in the fast energy range. For example, the partition of compound formation cross section into the elastic and inelastic channels depends on the elastic enhancement factor calculated from the statistical models. In addition, unitarity of S-matrix constrains this partition when the direct reactions are involved. Practically some simple assumptions, which many nuclear reaction model codes adopt, may work reasonably for the nuclear data evaluations. However, the uncertainties on the evaluated cross sections cannot go lower than the model uncertainty itself. We perform numerical simulations by generating the resonances using the R-matrix theory, and compare the energy (ensemble) averaged cross sections with the statistical theories, such as the theories of Moldauer, HRTW (Hofmann, Richert, Tepel, and Weidenmueller), KKM (Kawai-Kerman-McVoy), and GOE (Gaussian orthogonal ensemble).

Kawano, Toshihiko [Los Alamos National Laboratory; Talou, Patrick [Los Alamos National Laboratory

2012-09-18T23:59:59.000Z

342

Baryon history and cosmic star formation in non-Gaussian cosmological models: numerical simulations  

E-Print Network (OSTI)

We present the first numerical, N-body, hydrodynamical, chemical simulations of cosmic structure formation in the framework of non-Gaussian models. We study the impact of primordial non-Gaussianities on early chemistry (e, H, H+, H-, He, He+, He++, H2, H2+, D, D+, HD, HeH+), molecular and atomic gas cooling, star formation, metal (C, O, Si, Fe, Mg, S) enrichment, population III (popIII) and population II-I (popII) transition, and on the evolution of "visible" objects. We find that non-Gaussianities can have some consequences on baryonic structure formation at very early epochs, but the subsequent evolution at later times washes out any difference among the various models. When assuming reasonable values for primordial non-Gaussian perturbations, it turns out that they are responsible for: (i) altering early molecular fractions in the cold, dense gas phase of ~10 per cent; (ii) inducing small temperature fluctuations of ~15, and of the popIII/popII transition of up to some 10^7yr; (iv) determining variations of history of the Universe. We stress, though, that purely non-Gaussian effects might be difficult to address, since they are strictly twisted with additional physical phenomena (e.g. primordial gas bulk flows, unknown primordial popIII stellar mass function, etc.) that have similar or stronger impact on the behaviour of the baryons.

Umberto Maio; Francesca Iannuzzi

2011-03-16T23:59:59.000Z

343

NUMERICAL FLOW AND TRANSPORT SIMULATIONS SUPPORTING THE SALTSTONE FACILITY PERFORMANCE ASSESSMENT  

SciTech Connect

The Saltstone Disposal Facility Performance Assessment (PA) is being revised to incorporate requirements of Section 3116 of the Ronald W. Reagan National Defense Authorization Act for Fiscal Year 2005 (NDAA), and updated data and understanding of vault performance since the 1992 PA (Cook and Fowler 1992) and related Special Analyses. A hybrid approach was chosen for modeling contaminant transport from vaults and future disposal cells to exposure points. A higher resolution, largely deterministic, analysis is performed on a best-estimate Base Case scenario using the PORFLOW numerical analysis code. a few additional sensitivity cases are simulated to examine alternative scenarios and parameter settings. Stochastic analysis is performed on a simpler representation of the SDF system using the GoldSim code to estimate uncertainty and sensitivity about the Base Case. This report describes development of PORFLOW models supporting the SDF PA, and presents sample results to illustrate model behaviors and define impacts relative to key facility performance objectives. The SDF PA document, when issued, should be consulted for a comprehensive presentation of results.

Flach, G.

2009-02-28T23:59:59.000Z

344

Physical mechanism and numerical simulation of the inception of the lightning upward leader  

Science Conference Proceedings (OSTI)

The upward leader is a key physical process of the leader progression model of lightning shielding. The inception mechanism and criterion of the upward leader need further understanding and clarification. Based on leader discharge theory, this paper proposes the critical electric field intensity of the stable upward leader (CEFISUL) and characterizes it by the valve electric field intensity on the conductor surface, E{sub L}, which is the basis of a new inception criterion for the upward leader. Through numerical simulation under various physical conditions, we verified that E{sub L} is mainly related to the conductor radius, and data fitting yields the mathematical expression of E{sub L}. We further establish a computational model for lightning shielding performance of the transmission lines based on the proposed CEFISUL criterion, which reproduces the shielding failure rate of typical UHV transmission lines. The model-based calculation results agree well with the statistical data from on-site operations, which show the effectiveness and validity of the CEFISUL criterion.

Li Qingmin [Beijing Key Lab of High Voltage and EMC, School of Electric and Electronic Engineering, North China Electric Power University, Beijing 102206 (China) and State Key Lab of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206 (China); Lu Xinchang; Shi Wei; Zhang Li; Zou Liang; Lou Jie [Shandong Provincial Key Lab of UHV Technology and Gas Discharge, School of Electrical Engineering, Shandong University, Jinan 250061 (China)

2012-12-15T23:59:59.000Z

345

Numerical simulation of high-level radioactive nuclear waste glass production  

SciTech Connect

Vitrification of radioactive waste has become an international approach for converting highly radioactive wastes into a durable solid prior to placing them in a permanent disposal repository. The technology for the process is not new. The conversion melter is a direct descendant of all electric melters used for manufacturing of some commercial glass types. Therefore, the vitrification process of radioactive wastes inherits typical problems of all electric furnaces and creates some other specific problems such as noble metal sedimentation. The noble metals and nickel sulfides in the melter are heavier than molten glass and have a low solubility. In a reducing condition, these metals amalgamate and tend to settle on the melter floor. The metal deposit resulting from this settling has a potential to short circuit the melter. The objective of this paper is to identify the typical problems that have been encountered in the waste melter operations and to address how these problems can be tackled using state-of-the-art numerical simulation techniques. It is believed that the large amount of pilot-scale melter experience throughout the world, combined with the knowledge gained from state-of-the-art computer modeling techniques would give assurance that the existing and future radioactive wastes can be effectively converted into a durable glass material and safely placed in a permanent repository.

Choi, I.G. (Westinghouse Savannah River Co., Aiken, SC (United States)); Ungan, A. (Purdue Univ., Indianapolis, IN (United States). Dept. of Mechanical Engineering)

1991-01-01T23:59:59.000Z

346

Numerical simulation of high-level radioactive nuclear waste glass production  

SciTech Connect

Vitrification of radioactive waste has become an international approach for converting highly radioactive wastes into a durable solid prior to placing them in a permanent disposal repository. The technology for the process is not new. The conversion melter is a direct descendant of all electric melters used for manufacturing of some commercial glass types. Therefore, the vitrification process of radioactive wastes inherits typical problems of all electric furnaces and creates some other specific problems such as noble metal sedimentation. The noble metals and nickel sulfides in the melter are heavier than molten glass and have a low solubility. In a reducing condition, these metals amalgamate and tend to settle on the melter floor. The metal deposit resulting from this settling has a potential to short circuit the melter. The objective of this paper is to identify the typical problems that have been encountered in the waste melter operations and to address how these problems can be tackled using state-of-the-art numerical simulation techniques. It is believed that the large amount of pilot-scale melter experience throughout the world, combined with the knowledge gained from state-of-the-art computer modeling techniques would give assurance that the existing and future radioactive wastes can be effectively converted into a durable glass material and safely placed in a permanent repository.

Choi, I.G. [Westinghouse Savannah River Co., Aiken, SC (United States); Ungan, A. [Purdue Univ., Indianapolis, IN (United States). Dept. of Mechanical Engineering

1991-12-31T23:59:59.000Z

347

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

SciTech Connect

Planar flames are intrinsically unstable in open domains due to the thermal expansion across the burning front--the Landau-Darrieus instability. This instability leads to wrinkling and growth of the flame surface, and corresponding acceleration of the flame, until it is stabilized by cusp formation. We look at the Landau-Darrieus in stability for C/O thermonuclear flames at conditions relevant to the late stages of a Type Ia supernova explosion. Two-dimensional direct numerical simulations of both single-mode and multi-mode perturbations using a low Mach number hydrodynamics code are presented. We show the effect of the instability on the flame speed as a function of both the density and domain size, demonstrate the existence of the small scale cutoff to the growth of the instability, and look for the proposed breakdown of the non-linear stabilization at low densities. The effects of curvature on the flame as quantified through measurements of the growth rate and computation of the corresponding Markstein number. While accelerations of a few percent are observed, they are too small to have any direct outcome on the supernova explosion.

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

2003-11-24T23:59:59.000Z

348

Time scales of DNAPL migration in sandy aquifers examined via numerical simulation  

Science Conference Proceedings (OSTI)

The time required for dense nonaqueous phase liquid (DNAPL) to cease migrating following release to the subsurface is a valuable component of a site conceptual model. This study uses numerical simulation to investigate the migration of six different DNAPLs in sandy aquifers. The most influential parameters governing migration cessation time are the density and viscosity of the DNAPL and the mean hydraulic conductivity of the aquifer. Releases of between 1 and 40 drums of chlorinated solvent DNAPLs, characterized by relatively high density and low viscosity, require on the order of months to a few years to cease migrating in a heterogeneous medium sand aquifer having an average hydraulic conductivity of 7.4 x 10{sup -3} cm/s. In contrast to this, the release of 20 drums of coal tar {rho}{sub D} = 1061 kg/m{sup 3}, {mu}{sub D} = 0.161 Pa(.)s) requires more than 100 years to cease migrating in the same aquifer. Altering the mean hydraulic conductivity of the aquifer results in a proportional change in cessation times. Parameters that exhibit relatively little influence on migration time scales are the DNAPL-water interfacial tension, release volume, source capillary pressure, mean aquifer porosity, and ambient ground water hydraulic gradient. This study also demonstrates that low-density DNAPLs (e.g., coal tar) give rise to greater amounts of lateral spreading and greater amounts of pooling on capillary barriers than high-density DNAPLs such as trichloroethylene or tetrachloroethylene.

Gerhard, J.I.; Pang, T.; Kueper, B.H. [University of Edinburgh, Edinburgh (United Kingdom). Inst. of Infrastructure & Environmental

2007-03-15T23:59:59.000Z

349

Numerical simulation of clarifier-thickener units treating ideal suspensions with a flux density function having two inflection points  

Science Conference Proceedings (OSTI)

We consider a nonconvex conservation law modelling the settling of particles in ideal clarifier-thickener units. The flux function of this conservation law has an explicit spatial dependence that is discontinuous. Previous works by two of the authors, ... Keywords: Clarifier-thickener, Conservation law, Continuous sedimentation, Discontinuous flux, Finite difference method, Numerical simulation

R. BRger; F. Concha; K. H. Karlsen; A. NarvEz

2006-08-01T23:59:59.000Z

350

Numerical simulation of acoustic and internal gravity waves caused by inhomogeneity of wind field of the earth atmosphere  

Science Conference Proceedings (OSTI)

Dynamics of linear two and three-dimensional acoustic and internal gravity waves in nondissipative, isothermal stratified atmosphere in conditions of presence of a zonal wind by horizontal - vertical shear is investigated. There is shown, that the shear ... Keywords: acoustic and internal gravity waves, numerical simulation

Amiran Chitaladze

2009-06-01T23:59:59.000Z

351

Numerical simulation of four-field extended magnetohydrodynamics in dynamically adaptive curvilinear coordinates via Newton-Krylov-Schwarz  

Science Conference Proceedings (OSTI)

Numerical simulations of the four-field extended magnetohydrodynamics (MHD) equations with hyper-resistivity terms present a difficult challenge because of demanding spatial resolution requirements. A time-dependent sequence of r-refinement adaptive ... Keywords: Dynamically adaptive grid, Equidistribution principle, MHD, Magnetic reconnection, Monge-Ampre equation, Monge-Kantorovich optimization, NKS, Structured grid, r-Refinement

Xuefei Yuan; Stephen C. Jardin; David E. Keyes

2012-07-01T23:59:59.000Z

352

Original article: Comparison of numerical models in radiative heat transfer with application to circuit-breaker simulations  

Science Conference Proceedings (OSTI)

Two different modeling approaches for the numerical computation of the radiation energy exchange in the context of the simulation of high-voltage circuit breakers are investigated. These are the basic Radiative Transfer Equation method and the P1 model ... Keywords: CFD modeling, Circuit breakers, Finite volume discretization, P1 model, Radiative heat transfer

Matthieu Melot; Jean-Yves TrPanier; Ricardo Camarero; Eddy Petro

2012-08-01T23:59:59.000Z

353

Numerical Simulation of Thermal-Solid Coupling to Coal-Rock during the Process of Heat Injection Mine for CBM  

Science Conference Proceedings (OSTI)

For gaining effective influence radius of heat injection mine for CBM (Coal Bed Methane) and influence rules of permeability under the condition of temperature and effective stress, heat transfer and elastic mechanics theory combined, hooker law of thermal ... Keywords: heat injection, thermal-solid coupling, numerical simulation, effective influence radius, permeability

Xin Le Yang; Yong Li Zhang

2010-12-01T23:59:59.000Z

354

Vortex Rossby Waves in a Numerically Simulated Tropical Cyclone. Part II: The Role in Tropical Cyclone Structure and Intensity Changes  

Science Conference Proceedings (OSTI)

In Part I, the author analyzed the asymmetric structure in the inner core of a numerically simulated tropical cyclone and found that the asymmetry near the eyewall in the midlower troposphere is dominated by wavenumber-1 and -2 vortex Rossby ...

Yuqing Wang

2002-04-01T23:59:59.000Z

355

Numerical Simulations of Upstream Blocking, Columnar Disturbances, and Bores in Stably Stratified Shear Flows over an Obstacle  

Science Conference Proceedings (OSTI)

A two-dimensional, nonhydrostatic, elastic numerical model has been used to study the generation of gravity waves for a stably stratified shear flow over an obstacle. When a low-level wind shear is included in the simulation, we find that the ...

Chaing Chen; James W. Rottman; Steven E. Koch

1994-11-01T23:59:59.000Z

356

2-dimensional numerical simulations for the wave-wake-body interactions around circular cylinders in motion near seabed  

E-Print Network (OSTI)

The 2-dimensional, viscous and incompressible flow past a circular cylinder is investigated by solving the Navier-stokes equation. solved using CFD (Computational Fluid These equations are numerically Dynamics) methods on an overlapping multiblock grid system. In this thesis, several flow configurations, such as stationary and oscillating cylinder, were studied in order to predict and to understand the hydrodynamic forces. The results from the different simulations were compared with available experimental and numerical data, which confirmed the correctness and accuracy of the present method. The numerical computations successfully captured many important flow features for the various types of flow conditions. The present program code proves to be a powerful tool, by enabling the study of numerous interesting and useful research topics related to fluid-structure interactions, thereby, it will contribute to a better design of offshore structures.

Tavassoli, Armin

1999-01-01T23:59:59.000Z

357

Use of a Radar Simulator on the Output Fields from a Numerical Mesoscale Model to Analyze X-Band Rain Estimators  

Science Conference Proceedings (OSTI)

A full radar simulator, which works with the 3D output fields from a numerical mesoscale model, has been developed. This simulator uses a T-matrix code to calculate synthetic radar measurements, accounts for both backscattering and propagation ...

E-P. Zahiri; M. Gosset; J-P. Lafore; V. Gouget

2008-03-01T23:59:59.000Z

358

Numerical Simulation Study to Investigate Expected Productivity Improvement Using the "Slot-Drill" Completion  

E-Print Network (OSTI)

The "slot-drill" completion method, which utilizes a mechanically cut high-conductivity "slot" in the target formation created using a tensioned abrasive cable, has been proposed as an alternative stimulation technique for shale-gas and other low/ultra-low permeability formations. This thesis provides a comprehensive numerical simulation study on the "slot drill" completion technique. Using a Voronoi gridding scheme, I created representative grid systems for the slot-drill completion, as well as for the case of a vertical well with a single fracture, the case of a horizontal well with multiple hydraulic fractures, and various combinations of these completions. I also created a rectangular slot configuration, which is a simplified approximation of the actual "slot-drill" geometry, and investigated the ability of this rectangular approximation to model flow from the more complicated (actual) slot-drill configuration(s). To obtain the maximum possible diagnostic and analytical value, I simulated up to 3,000 years of production, allowing the assessment of production up to the point of depletion (or boundary-dominated flow). These scenarios provided insights into all the various flow regimes, as well as provided a quantitative evaluation of all completion schemes considered in the study. The results of my study illustrated that the "slot-drill" completion technique was not, in general, competitive in terms of reservoir performance and recovery compared to the more traditional completion techniques presently in use. Based on my modeling, it appears that the larger surface area to flow that multistage hydraulic fracturing provides is much more significant than the higher conductivity achieved using the slot-drill technique. This work provides quantitative results and diagnostic interpretations of productivity and flow behavior for low and ultra-low permeability formations completed using the slot-drill method. The results of this study can be used to (a) help evaluate the possible application of the "slot-drill" technique from the perspective of performance and recovery, and (b) to establish aggregated economic factors for comparing the slot-drill technique to more conventional completion and stimulation techniques applied to low and ultra-low permeability reservoirs.

Odunowo, Tioluwanimi Oluwagbemiga

2012-05-01T23:59:59.000Z

359

NUMERICAL SIMULATIONS OF CHROMOSPHERIC HARD X-RAY SOURCE SIZES IN SOLAR FLARES  

Science Conference Proceedings (OSTI)

X-ray observations are a powerful diagnostic tool for transport, acceleration, and heating of electrons in solar flares. Height and size measurements of X-ray footpoint sources can be used to determine the chromospheric density and constrain the parameters of magnetic field convergence and electron pitch-angle evolution. We investigate the influence of the chromospheric density, magnetic mirroring, and collisional pitch-angle scattering on the size of X-ray sources. The time-independent Fokker-Planck equation for electron transport is solved numerically and analytically to find the electron distribution as a function of height above the photosphere. From this distribution, the expected X-ray flux as a function of height, its peak height, and full width at half-maximum are calculated and compared with RHESSI observations. A purely instrumental explanation for the observed source size was ruled out by using simulated RHESSI images. We find that magnetic mirroring and collisional pitch-angle scattering tend to change the electron flux such that electrons are stopped higher in the atmosphere compared with the simple case with collisional energy loss only. However, the resulting X-ray flux is dominated by the density structure in the chromosphere and only marginal increases in source width are found. Very high loop densities (>10{sup 11} cm{sup -3}) could explain the observed sizes at higher energies, but are unrealistic and would result in no footpoint emission below about 40 keV, contrary to observations. We conclude that within a monolithic density model the vertical sizes are given mostly by the density scale height and are predicted smaller than the RHESSI results show.

Battaglia, M.; Kontar, E. P.; Fletcher, L.; MacKinnon, A. L., E-mail: marina.battaglia@fhnw.ch [SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ (United Kingdom)

2012-06-10T23:59:59.000Z

360

Formation and Quasi-Periodic Behavior of Outer Spiral Rainbands in a Numerically Simulated Tropical Cyclone  

Science Conference Proceedings (OSTI)

The formation and quasi-periodic behavior of outer spiral rainbands in a tropical cyclone simulated in the cloud-resolving tropical cyclone model version 4 (TCM4) are analyzed. The outer spiral rainbands in the simulation are preferably initiated ...

Qingqing Li; Yuqing Wang

2012-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Mesoscale Boundary Layer Evolution over Complex Terrain. Part I. Numerical Simulation of the Diurnal Cycle  

Science Conference Proceedings (OSTI)

The continuous development of a meso-?-scale boundary layer over sloping terrain upwind of a high mountain barrier was simulated through a complete diurnal cycle using a nonhydrostatic boundary-layer model. The simulation detailed the evolution ...

David C. Bader; Thomas B. McKee; Gregory J. Tripoli

1987-10-01T23:59:59.000Z

362

Numerical Simulations of the 2 August 1981 CCOPE Supercell Storm with and without Ice Microphysics  

Science Conference Proceedings (OSTI)

The Wisconsin Dynamical-Microphysical Model is used in two simulations of the 2 August 1981 supercell that passed through the Cooperative Convective Precipitation Experiment in southeastern Montana. The first simulation uses liquid water-only ...

Daniel E. Johnson; Pao K. Wang; Jerry M. Straka

1993-04-01T23:59:59.000Z

363

TEMPLUM: a process adapted numerical simulation code for the 3D predictive assessment of laser surface heat treatments in planar geometry  

Science Conference Proceedings (OSTI)

A process adapted numerical simulation code for the 3D predictive assessment of laser heat treatment of materials has been developed. Primarily intended for the analysis of the laser transformation hardening of steels, the code has been successfully ... Keywords: finite element, heat conduction, laser surface treatments, modeling, numerical analysis, optical glass polishing, simulation, transformation hardening

A. A. Garca-Beltrn; J. L. Ocaa; C. L. Molpeceres

2008-02-01T23:59:59.000Z

364

Physical modeling and numerical simulation of subcooled boiling in one- and three-dimensional representation of bundle geometry  

Science Conference Proceedings (OSTI)

Numerical simulation of subcooled boiling in one-dimensional geometry with the Homogeneous Equilibrium Model (HEM) may yield difficulties related to the very low sonic velocity associated with the HEM. These difficulties do not arise with subcritical flow. Possible solutions of the problem include introducing a relaxation of the vapor production rate. Three-dimensional simulations of subcooled boiling in bundle geometry typical of fast reactors can be performed by using two systems of conservation equations, one for the HEM and the other for a Separated Phases Model (SPM), with a smooth transition between the two models.

Bottoni, M.; Lyczkowski, R.; Ahuja, S.

1995-07-01T23:59:59.000Z

365

Development of a Two-Fluid Drag Law for Clustered Particles Using Direct Numerical Simulation and Validation through Experiments  

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

Two-Fluid Drag Law Two-Fluid Drag Law for Clustered Particles Using Direct Numerical Simulation and Validation through Experiments Background The Historically Black Colleges and Universities and Other Minority Institutions (HBCU/ OMI) Research and Development (R&D) Program within the U. S. Department of Energy (DOE) Office of Fossil Energy (FE) provides a mechanism for cooperative FE R&D projects between DOE and the HBCU/OMI community. This program encourages

366

Modeling-Computer Simulations At Walker-Lane Transitional Zone...  

Open Energy Info (EERE)

in the Great Basin, Louie and Coolbaugh. We have compiled velocity information from sources in the literature, results of previous seismic experiments and...

367

Modeling-Computer Simulations (Muffler & Cataldi, 1978) | Open...  

Open Energy Info (EERE)

heat flux, 2. Volume methods, 3. Planar fracture method, 4. Methods of magmatic head budget. We shall describe each of these categories in turn, deferring evaluation of their...

368

Modeling-Computer Simulations (Mcnitt, 1978) | Open Energy Information  

Open Energy Info (EERE)

as developed by Bodvarsson (1974), and the decline curve method, as used in the petroleum industry. Neither of these methods has given very satisfactory results; the energy...

369

Modeling-Computer Simulations (Brikowski, 2001) | Open Energy...  

Open Energy Info (EERE)

not indicated DOE-funding Unknown References Tom H. Brikowski (2001) Modeling Supercritical Systems With Tough2- The Eoslsc Equation Of State Module And A Basin And Range...

370

Modeling-Computer Simulations (Ranalli & Rybach, 2005) | Open...  

Open Energy Info (EERE)

Notes re: Heat Flow and Temp Logs References G. Ranalli, L. Rybach (2005) Heat Flow, Heat Transfer And Lithosphere Rheology In Geothermal Areas- Features And Examples...

371

Numerical Weather Simulations with Different Formulations for the Advection of Humidity and Cloud Water  

Science Conference Proceedings (OSTI)

This study investigates the effect on short-range weather prediction of using different numerical advection schemes for humidity and cloud water. Comparisons are made between predictions using the basic centered and upstream schemes and the more ...

Erik Berge; Jn Egill Kristjnsson

1992-08-01T23:59:59.000Z

372

The Structure and Evolution of a Numerically Simulated High-Precipitation Supercell Thunderstorm  

Science Conference Proceedings (OSTI)

The structure and evolution of a high-precipitation (HP) supercell thunderstorm is investigated using a three-dimensional, nonhydrostatic, cloud-scale numerical model (TASS). The model is initialized with a sounding taken from a mesoscale ...

Mark S. Kulie; Yuh-Lang Lin

1998-08-01T23:59:59.000Z

373

Numerical simulation of micro/mini-channel based methane-steam reformer.  

E-Print Network (OSTI)

??Numerical modeling of methane-steam reforming is performed in a micro/mini-channel with heat input through catalytic channel walls. The low-Mach number, variable density Navier-Stokes equations together (more)

[No author

2010-01-01T23:59:59.000Z

374

Numerical Simulation of CloudClear Air Interfacial Mixing: Effects on Cloud Microphysics  

Science Conference Proceedings (OSTI)

This paper extends the previously published numerical study of Andrejczuk et al. on microscale cloudclear air mixing. Herein, the primary interest is on microphysical transformations. First, a convergence study is performedwith well-resolved ...

Miroslaw Andrejczuk; Wojciech W. Grabowski; Szymon P. Malinowski; Piotr K. Smolarkiewicz

2006-12-01T23:59:59.000Z

375

The Maximum Intensity of Tropical Cyclones in Axisymmetric Numerical Model Simulations  

Science Conference Proceedings (OSTI)

An axisymmetric numerical model is used to evaluate the maximum possible intensity of tropical cyclones. As compared with traditionally formulated nonhydrostatic models, this new model has improved mass and energy conservation in saturated ...

George H. Bryan; Richard Rotunno

2009-06-01T23:59:59.000Z

376

The Dependence of Numerically Simulated Convective Storms on Vertical Wind Shear and Buoyancy  

Science Conference Proceedings (OSTI)

The effects of vertical wind shear and buoyancy on convective storm structure and evolution are investigated with the use of a three-dimensional numerical cloud model. By varying the magnitude of buoyant energy and one-directional vertical shear ...

M. L. Weisman; J. B. Klemp

1982-06-01T23:59:59.000Z

377

Patterns of Local Circulation in the Itaipu Lake Area: Numerical Simulations of Lake Breeze  

Science Conference Proceedings (OSTI)

The lake-breeze circulation in the Itaipu region was investigated numerically using a nonhydrostatic version of the Topographic Vorticity Model. The area of study corresponds to a 100 km 180 km rectangle, located on the BrazilParaguay border, ...

Snia M. S. Stivari; Amauri P. de Oliveira; Hugo A. Karam; Jacyra Soares

2003-01-01T23:59:59.000Z

378

A Comprehensive Radiation Scheme for Numerical Weather Prediction Models with Potential Applications in Climate Simulations  

Science Conference Proceedings (OSTI)

A comprehensive scheme for the parameterization of radiative transfer in numerical weather Prediction (NWP) models has been developed. The scheme is based on the solution of the ?-two-stream version of the radiative transfer equation ...

Bodo Ritter; Jean-Francois Geleyn

1992-02-01T23:59:59.000Z

379

Numerical simulations of island-induced circulations and windward katabatic flow over the Guadeloupe archipelago  

Science Conference Proceedings (OSTI)

This article deals with the first high resolution numerical modelling of the weather over the small and high islands of the Guadeloupe archipelago. Its main goal is to analyze the mechanisms which drive local-scale airflow circulations over this ...

Raphal Cc; Didier Bernard; Christophe DAlexis; Jean-Franois Dorville

380

Numerical Simulation of Nonlinear Mesoscale Circulations Induced by the Thermal Heterogeneities of Land Surface  

Science Conference Proceedings (OSTI)

Mesoscale circulations forced by a random distribution of surface sensible heat flux have been investigated using a three-dimensional numerical model. The complex land surface is modeled as a homogeneous random field characterized by a spectral ...

Jingfeng Wang; Elfatih A. B. Eltahir; Rafael L. Bras

1998-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Direct Numerical Simulation of the PlumbMcEwan Laboratory Analog of the QBO  

Science Conference Proceedings (OSTI)

The laboratory experiment of Plumb and McEwan demonstrates the principal mechanism of periodically reversing winds observed in the stratospherethe quasi-biennial oscillation (QBO). However, despite numerous studies, some aspects of the QBO and ...

Nils P. Wedi; Piotr K. Smolarkiewicz

2006-12-01T23:59:59.000Z

382

The Generation and Propagation of a Nocturnal Squall Line. Part II: Numerical Simulations  

Science Conference Proceedings (OSTI)

The mechanisms behind the convective regeneration that occurred at midnight on 26 May 1985 in the Kansas PRE-STORM network (described in Part I) are examined with a numerical cloud model. Three mechanisms that could have caused the regeneration ...

N. A. Crook; R. E. Carbone; M. W. Moncrieff; J. W. Conway

1990-01-01T23:59:59.000Z

383

Numerical Simulation of a Subtropical Squall Line over the Taiwan Strait  

Science Conference Proceedings (OSTI)

A two-dimensional, time-dependent, and nonhydrostatic numerical cloud model is used to study the development and structure of a subtropical squall line that occurred during TAMEX (Taiwan Area Mesoscale Experiment). The model includes a ...

Wei-Kuo Tao; Joanne Simpson; Su-Tzai Soong

1991-11-01T23:59:59.000Z

384

The Numerical Simulation of Airflow and Dispersion in Three-Dimensional Atmospheric Recirculation Zones  

Science Conference Proceedings (OSTI)

A three-dimensional, nonhydrostatic numerical code using the two-equation turbulence closure was developed to model the atmospheric transport and diffusion of pollutants over buildings and a three-dimensional hill. The standard engineering two-...

Paul Dawson; David E. Stock; Brian Lamb

1991-07-01T23:59:59.000Z

385

Numerical Simulation of a 4-Day Early Spring Storm Period in the Black Hills  

Science Conference Proceedings (OSTI)

This paper illustrates the potential for mesoscale models to depict the distribution of precipitation in orographic situations. The study covers a 4-day time period in April 1995. The domain of the numerical model covers much of western South ...

R. D. Farley; D. L. Hjermstad; H. D. Orville

2000-08-01T23:59:59.000Z

386

Parameterization and Impact of Ice initiation Processes Relevant to Numerical Model Simulations of Cirrus Clouds  

Science Conference Proceedings (OSTI)

An effort to improve descriptions of ice initiation processes of relevance to cirrus clouds for use in regional-scale numerical cloud models with bulk microphysical schemes is described. This is approached by deriving practical parameterizations ...

Paul J. DeMott; Michael P. Meyers; William R. Cotton

1994-01-01T23:59:59.000Z

387

Numerical Simulation of Flow around a Tall Isolated Seamount. Part II: Resonant Generation of Trapped Waves  

Science Conference Proceedings (OSTI)

A sigma-coordinate, primitive equation ocean circulation model is used to explore the problem of the remnant generation of trapped waves about a tall, circular, isolated seamount by an incident oscillatory barotropic current. The numerical ...

Dale B. Haidvogel; Aike Beckmann; David C. Chapman; Ray-Qing Lin

1993-11-01T23:59:59.000Z

388

NREL Developing a Numerical Simulation Tool to Study Hydrokinetic Energy Conversion Devices and Arrays (Fact Sheet)  

Science Conference Proceedings (OSTI)

New code will help accelerate design improvements by providing a high-fidelity simulation tool to study power performance, structural loading, and the interactions between devices in arrays.

Not Available

2012-02-01T23:59:59.000Z

389

Numerical simulation on dense gas dispersion and fire characteristics after liquefied natural gas release.  

E-Print Network (OSTI)

??This PhD dissertation mainly studies the prediction, simulation and mitigation methods of the two main hazards in LNG (Liquefied Natural Gas) industry, LNG vapor dense (more)

Sun, Biao

2012-01-01T23:59:59.000Z

390

Numerical Simulation of Brake Discs of CRH3 High-Speed Trains ...  

Science Conference Proceedings (OSTI)

... the research object?the course of emergency brake was simulated by ANSYS. .... Energy X-Ray Diffraction Microscopy Studies of Bulk Polycrystal Responses.

391

Numerical simulation of thermal properties in two-dimensional Yukawa systems  

E-Print Network (OSTI)

New results obtained for thermal conduction in 2D Yukawa systems. The results of numerical study of heat transfer processes for quasi equilibrium systems with parameters close to conditions in laboratory experiments with dusty plasma are presented. The Green-Kubo relations are used to calculate thermal conductivity and diffusivity coefficients. For the first time the influence of dissipation (friction) on the heat transfer in non-ideal systems is studied. New approximation is suggested for thermal diffusivity. The comparison with the existing experimental and numerical results is shown.

Khrustalyov, Yu V

2011-01-01T23:59:59.000Z

392

3D-radiation hydro simulations of disk-planet interactions: I. Numerical algorithm and test cases  

E-Print Network (OSTI)

We study the evolution of an embedded protoplanet in a circumstellar disk using the 3D-Radiation Hydro code TRAMP, and treat the thermodynamics of the gas properly in three dimensions. The primary interest of this work lies in the demonstration and testing of the numerical method. We show how far numerical parameters can influence the simulations of gap opening. We study a standard reference model under various numerical approximations. Then we compare the commonly used locally isothermal approximation to the radiation hydro simulation using an equation for the internal energy. Models with different treatments of the mass accretion process are compared. Often mass accumulates in the Roche lobe of the planet creating a hydrostatic atmosphere around the planet. The gravitational torques induced by the spiral pattern of the disk onto the planet are not strongly affected in the average magnitude, but the short time scale fluctuations are stronger in the radiation hydro models. An interesting result of this work lies in the analysis of the temperature structure around the planet. The most striking effect of treating the thermodynamics properly is the formation of a hot pressure--supported bubble around the planet with a pressure scale height of H/R ~ 0.5 rather than a thin Keplerian circumplanetary accretion disk. We also observe an outflow of gas above and below the planet during the gap opening phase.

H. Klahr; W. Kley

2005-10-13T23:59:59.000Z

393

Numerical simulation of the impact and deposition of charged particulate droplets  

Science Conference Proceedings (OSTI)

This work addresses the impact and deposition of charged ''cluster-droplets'', comprised of particulates, on electrified surfaces. A direct numerical method is developed, based on an implicit, staggered, time-stepping scheme which separates the impulsive ... Keywords: Charged particulates, Clusters, Impact, Staggering scheme

T. I. Zohdi

2013-01-01T23:59:59.000Z

394

Numerical Simulation of Thunderstorm Outflow Dynamics. Part I: Outflow Sensitivity Experiments and Turbulence Dynamics  

Science Conference Proceedings (OSTI)

In this first paper of a two-part series, a two-dimensional numerical model is developed and used to investigate the dynamics of thunderstorm outflows. By focusing only on the outflow and using essentially inviscid equations and high spatial ...

Kelvin K. Droegemeier; Robert B. Wilhelmson

1987-04-01T23:59:59.000Z

395

Influence of the Mediterranean Sea on the West African Monsoon: intraseasonal variability in numerical simulations  

E-Print Network (OSTI)

Influence of the Mediterranean Sea on the West African Monsoon: intraseasonal variability in the Mediterranean sea on the West African monsoon is investigated, analysing the outputs of numerical sensitivity underlying the Mediterranean action on the West African monsoon is based on the modifications produced

Paris-Sud XI, Université de

396

Numerical Simulation of the Influence of Sea Surface Temperature on Translating Tropical Cyclones  

Science Conference Proceedings (OSTI)

A three-dimensional numerical model with a domain of 3000 km3000 km and horizontal resolution of 60 km is used to study the influence of sea surface temperature (SST) on the behavior of tropical cyclones translating with mean flows in the ...

Simon W. Chang; Rangarao V. Madala

1980-12-01T23:59:59.000Z

397

Mesoscale Lake-effect Snowstorms in the Vicinity of Lake Michigan: Linear Theory and Numerical Simulations  

Science Conference Proceedings (OSTI)

Mesoscale lake-effect snowstorms in the vicinity of Lake Michigan are studied by a linear steady-state analytic model and a nonlinear time-dependent numerical model with parameterized subgrid-scale physics. The solutions of the linear model show ...

Hsiao-ming Hsu

1987-04-01T23:59:59.000Z

398

Numerical simulation of non-linear wave tank based on the ALE algorithm  

Science Conference Proceedings (OSTI)

Numerical Wave Tank NWT becomes more and more prominent in the corresponding scientific research. On the basis of the Navier-Stokes N-S equation, the early application be adopted for discretising and calculating the specific region is by Volume of Fluid ...

Feng Zhu; Weihua Zhu; Y. N. Wang; B. Fang; S. L. Zhao

2013-07-01T23:59:59.000Z

399

Numerical simulation of transient, incongruent vaporization induced by high power laser  

Science Conference Proceedings (OSTI)

A mathematical model and numerical calculations were developed to solve the heat and mass transfer problems specifically for uranum oxide subject to laser irradiation. It can easily be modified for other heat sources or/and other materials. In the uranium-oxygen system, oxygen is the preferentially vaporizing component, and as a result of the finite mobility of oxygen in the solid, an oxygen deficiency is set up near the surface. Because of the bivariant behavior of uranium oxide, the heat transfer problem and the oxygen diffusion problem are coupled and a numerical method of simultaneously solving the two boundary value problems is studied. The temperature dependence of the thermal properties and oxygen diffusivity, as well as the highly ablative effect on the surface, leads to considerable non-linearities in both the governing differential equations and the boundary conditions. Based on the earlier work done in this laboratory by Olstad and Olander on Iron and on Zirconium hydride, the generality of the problem is expanded and the efficiency of the numerical scheme is improved. The finite difference method, along with some advanced numerical techniques, is found to be an efficient way to solve this problem.

Tsai, C.H.

1981-01-01T23:59:59.000Z

400

Experimental and numerical simulations predictions comparison of power and efficiency in hydraulic turbine  

Science Conference Proceedings (OSTI)

On-site power and mass flow rate measurements were conducted in a hydroelectric power plant (Mexico). Mass flow rate was obtained using Gibson's water hammer-based method. A numerical counterpart was carried out by using the commercial CFD software, ...

Laura Castro; Gustavo Urquiza; Adam Adamkowski; Marcelo Reggio

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Numerical Simulation of Wind-Driven Circulation in a Subtropical/Subpolar Basin  

Science Conference Proceedings (OSTI)

A one-and-one-half layer, reduced gravity model has been studied numerically in parallel to previous analytical studies by Huang and Flierl. The main emphasis is on a strong nonlinearity associated with the layer depth, especially when the lower ...

Rui Xin Huang

1986-10-01T23:59:59.000Z

402

A Three-Dimensional Numerical Simulation of a Great Plains Dryline  

Science Conference Proceedings (OSTI)

A three-dimensional, nonhydrostatic, nested grid version of the Colorado State University Regional Atmospheric Modeling System (RAMS) was used to perform simulations of an actual dryline that was observed as part of the COPS-91 field experiment ...

B. L. Shaw; R. A. Pielke; C. L. Ziegler

1997-07-01T23:59:59.000Z

403

Effect of Vertical Wind Shear on Numerically Simulated Multicell Storm Structure  

Science Conference Proceedings (OSTI)

A strictly two-dimensional cloud model was used to gauge the effect of vertical wind shear on the mature phase behavior of model-simulated multicellular storms, extending the previous work of the authors. We specifically examined the propagation ...

Robert G. Fovell; Yoshi Ogura

1989-10-01T23:59:59.000Z

404

Assessment of the State-Of-The-Art of Numerical Simulation of Enhanced Geothermal Systems  

DOE Green Energy (OSTI)

The reservoir features of importance in the operation of enhanced geothermal systems are described first (Section 2). The report then reviews existing reservoir simulators developed for application to HDR reservoirs (Section 3), hydrothermal systems (Section 4), and nuclear waste isolation (Section 5), highlighting capabilities relevant to the evaluation and assessment of EGS. The report focuses on simulators that include some representation of flow in fractures, only mentioning other simulators, such as general-purpose programs or groundwater models (Section 6). Following these detailed descriptions, the report summarizes and comments on the simulators (Section 7), and recommends a course of action for further development (Section 8). The references are included in Section 9. Appendix A contains contractual information, including a description of the original and revised scope of work for this study. Appendix B presents comments on the draft report from DOE reviewer(s) and the replies of the authors to those comments. [DJE-2005

None

1999-11-01T23:59:59.000Z

405

A Case Study of Lid Evolution Using Analyses of Observational Data and a Numerical Model Simulation  

Science Conference Proceedings (OSTI)

A case of lid formation and evolution over the southern Great Plains during early spring is analyzed using conventional data analysis and a 120-h simulation from the Pennsylvania State University/National Center for Atmospheric Research Mesoscale ...

John M. Lanicci; Thomas T. Warner

1997-06-01T23:59:59.000Z

406

Numerical Simulations of Observed Arctic Stratus Clouds Using a Second-Order Turbulence Closure Model  

Science Conference Proceedings (OSTI)

A high-resolution one-dimensional version of a second-order turbulence closure radiative-convective model, developed at Los Alamos National Laboratory, is used to simulate the interactions among turbulence, radiation, and bulk cloud parameters in ...

W. S. Smith; C-Y. J. Kao

1996-01-01T23:59:59.000Z

407

Numerical Simulation of Land Subsidence in the Los Banos-Kettleman City Area, California  

E-Print Network (OSTI)

risk assessment of land subsidence in Shanhai. EnvironmentelObserved and simulated land subsidence for extenso meter 1 .and Miller, R. E. 1975. land subsidence due to ground water

Larson, Keith J; Basagaoglu, Hakan; Marino, Miguel

2001-01-01T23:59:59.000Z

408

Laboratory Studies and Numerical Simulations of Cloud Droplet Formation under Realistic Supersaturation Conditions  

Science Conference Proceedings (OSTI)

In this paper, a new device is introduced to study the formation and growth of cloud droplets under near-atmospheric supersaturations. The new device, called the Leipzig Aerosol Cloud Interaction Simulator (LACIS), is based on a laminar flow ...

F. Stratmann; A. Kiselev; S. Wurzler; M. Wendisch; J. Heintzenberg; R. J. Charlson; K. Diehl; H. Wex; S. Schmidt

2004-06-01T23:59:59.000Z

409

Numerical Simulations and a Conceptual Model of the Stratocumulus to Trade Cumulus Transition  

Science Conference Proceedings (OSTI)

A two-dimensional eddy-resolving model is used to study the transition from the stratocumulus topped boundary layer to the trade cumulus boundary layer. The 10-day simulations use an idealized Lagrangian trajectory representative of summertime ...

Matthew C. Wyant; Christopher S. Bretherton; Hugh A. Rand; David E. Stevens

1997-01-01T23:59:59.000Z

410

Similarity Statistics from a Direct Numerical Simulation of the Neutrally Stratified Planetary Boundary Layer  

Science Conference Proceedings (OSTI)

The turbulent flow in the unstratified Ekman layer over a smooth surface for the case of no horizontal rotation has been simulated. All relevant scales of motion are resolved so that no subgrid-scale parameterization is needed. The Reynolds ...

G. N. Coleman

1999-03-01T23:59:59.000Z

411

Numerically Simulated Electrification and Lightning of the 29 June 2000 STEPS Supercell Storm  

Science Conference Proceedings (OSTI)

A three-dimensional dynamic cloud model incorporating airflow dynamics, microphysics, and thunderstorm electrification mechanisms is used to simulate the first 3 h of the 29 June 2000 supercell from the Severe Thunderstorm Electrification and ...

Kristin M. Kuhlman; Conrad L. Ziegler; Edward R. Mansell; Donald R. MacGorman; Jerry M. Straka

2006-10-01T23:59:59.000Z

412

Interactions between a Developing Mesoscale Convective System and Its Environment. Part II: Numerical Simulation  

Science Conference Proceedings (OSTI)

The 19 July 1993 mesoscale convective system (MCS), discussed in Part I, was simulated using the Regional Atmospheric Modeling System (RAMS). The model was initialized with variable physiographic and atmospheric data with the goal of reproducing ...

Jason E. Nachamkin; William R. Cotton

2000-05-01T23:59:59.000Z

413

Numerical Simulation of CO2 Sequestration in Natural CO2 Reservoirs on the Colorado Plateau  

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

Simulation of CO Simulation of CO 2 Sequestration in Natural CO 2 Reservoirs on the Colorado Plateau Stephen P. White (S.White@irl.cri.nz, (64) 4 5690000) Graham J. Weir (G.Weir@irl.cri.nz, (64) 4 5690000) Warwick M. Kissling (W.Kissling@irl.cri.nz, (64) 4 5690000) Industrial Research Ltd. P.O. Box 31310 Lower Hutt, New Zealand Abstract This paper outlines the proposed research and summarizes pre-project work that forms a basis for a new research program on CO 2 sequestration in saline aquifers. The pre-project work considers storage and disposal of CO 2 several kilometers beneath the surface in generic aquifers and demonstrates the use of reactive chemical transport modeling to simulate mineral sequestration of CO 2. The current research project applies these techniques to particular saline

414

Numerical Simulation of the Airflow over Lake Michigan for a Major Lake-Effect Snow Event  

Science Conference Proceedings (OSTI)

A mesoscale model is used to simulate the airflow over Lake Michigan for the major lake-effect snowstorm of 10 December 1977. This storm was characterized by a land breeze circulation and a narrow shore-parallel radar reflectivity band. The model ...

Mark R. Hjelmfelt; Roscoe R. Braham Jr.

1983-01-01T23:59:59.000Z

415

Numerical simulation of a fuel droplet laden exothermic reacting mixing layer  

E-Print Network (OSTI)

the gas phase. The simulation parameters study the effects of the fuel composition, reaction stoichiometry role of carrier gas fuel to the reaction. Local flame extinction is markedly increased for non to the large occurrence in a variety of natural and practical applications, multiphase tur- bulent combustion

Miller, Richard S.

416

Algorithm for direct numerical simulation of emulsion flow through a granular material  

Science Conference Proceedings (OSTI)

A multipole-accelerated 3D boundary-integral algorithm capable of modelling an emulsion flow through a granular material by direct multiparticle-multidrop simulations in a periodic box is developed and tested. The particles form a random arrangement ... Keywords: Deformable drop, Emulsion, Granular material, Multipole

Alexander Z. Zinchenko; Robert H. Davis

2008-08-01T23:59:59.000Z

417

Numerical Simulation of Heavy Precipitation in Northern Baja California and Southern California  

Science Conference Proceedings (OSTI)

The fifth-generation Pennsylvania State UniversityNCAR Mesoscale Model (MM5) was used to simulate the heavy-precipitation events of 621 January 1993 during a moderate El Nio that produced severe flooding, landslides, and the loss of many lives ...

Ruth Cerezo-Mota; Tereza Cavazos; Luis M. Farfn

2006-02-01T23:59:59.000Z

418

Tropical Cyclogenesis Associated with Rossby Wave Energy Dispersion of a Preexisting Typhoon. Part II: Numerical Simulations  

Science Conference Proceedings (OSTI)

The cyclogenesis events associated with the tropical cyclone (TC) energy dispersion are simulated in a 3D model. A new TC with realistic dynamic and thermodynamic structures forms in the wake of a preexisting TC when a large-scale monsoon gyre or ...

Tim Li; Xuyang Ge; Bin Wang; Yongti Zhu

2006-05-01T23:59:59.000Z

419

Numerical Simulation of Hurricane Bonnie (1998). Part I: Eyewall Evolution and Intensity Changes  

Science Conference Proceedings (OSTI)

In this study, a 5-day explicit simulation of Hurricane Bonnie (1998) is performed using the fifth-generation Pennsylvania State UniversityNational Center for Atmospheric Research Mesoscale Model (MM5) with the finest grid length of 4 km. The ...

Tong Zhu; Da-Lin Zhang; Fuzhong Weng

2004-01-01T23:59:59.000Z

420

Optimization of interdigitated back contact silicon heterojunction solar cells by two-dimensional numerical simulation  

DOE Green Energy (OSTI)

In this paper, two-dimensional (2D) simulation of interdigitated back contact silicon heterojunction (IBC-SHJ) solar cells is presented using Sentaurus Device, a software package of Synopsys TCAD. A model is established incorporating a distribution of trap states of amorphous-silicon material and thermionic emission across the amorphous-silicon / crystalline-silicon heterointerface. The 2D nature of IBC-SHJ device is evaluated and current density-voltage (J-V) curves are generated. Optimization of IBC-SHJ solar cells is then discussed through simulation. It is shown that the open circuit voltage (VOC) and short circuit current density (JSC) of IBC-SHJ solar cells increase with decreasing front surface recombination velocity. The JSC improves further with the increase of relative coverage of p-type emitter contacts, which is explained by the simulated and measured position dependent laser beam induced current (LBIC) line scan. The S-shaped J-V curves with low fill factor (FF) observed in experiments are also simulated, and three methods to improve FF by modifying the intrinsic a-Si buffer layer are suggested: (i) decreased thickness, (ii) increased conductivity, and (iii) reduced band gap. With all these optimizations, an efficiency of 26% for IBC-SHJ solar cells is potentially achievable.

Lu, Meijun; Das, Ujjwal; Bowden, Stuart; Hegedus, Steven; Birmire, Robert

2009-06-09T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

Low-Level Jet Development during a Numerically Simulated Return Flow Event  

Science Conference Proceedings (OSTI)

The evolution of the southerly low-level jet (LLJ) during a return flow event is studied using output from the Penn State/NCAR Mesoscale Model (Version 4). Three geographically different southerly LLJs develop in the simulation: one over the ...

Richard C. Igau; John W. Nielsen-Gammon

1998-11-01T23:59:59.000Z

422

Numerical simulation of turbulent flow in complex geometries used in power plants  

Science Conference Proceedings (OSTI)

Performance degradations or improvements of coal-fired power stations depend on effective functioning of pulveriser equipment and combustion efficiency of furnaces in boilers. The function of a pulveriser is to grind the lumped coal and transfer the ... Keywords: CFD, coal fired power station, flow simulation, geometrical modelling, grid generation, particle trajectories, pulveriser, roller mill, turbulent flow, two-phase flow

C. Bhasker

2002-02-01T23:59:59.000Z

423

Numerical Simulations of the Marine Stratocumulus-Capped Boundary Layer and Its Diurnal Variation  

Science Conference Proceedings (OSTI)

A high-resolution one-dimensional version of a second-order turbulence radiativeconvective model, developed at Los Alamos National Laboratory, is used to simulate the diurnal cycle of the marine stratocumulus cloud-capped boundary layer. The ...

W. S. Smith; C-Y. J. Kao

1996-08-01T23:59:59.000Z

424

Numerical Simulation of the North Atlantic Ocean at 1/10  

Science Conference Proceedings (OSTI)

In this paper an initial analysis of an 0.1 simulation of the North Atlantic Ocean using a level-coordinate ocean general circulation model forced with realistic winds covering the period 198596 is presented. Results are compared to the North ...

Richard D. Smith; Mathew E. Maltrud; Frank O. Bryan; Matthew W. Hecht

2000-07-01T23:59:59.000Z

425

Numerical Simulation of Polycyclic Aromatic Hydrocarbon Formation in n-Heptane HCCI Combustion  

Science Conference Proceedings (OSTI)

By modifying the SENKIN code of CHEMKIN chemical kinetics package, the combustion processes and the characteristics of hydrocarbon (HC) and carbon monoxide(CO) emissions of a HCCI engine were simulated. Furthermore, the formation of benzene (A1) and ... Keywords: n-neptane, HCCI, multi-zone model, polycyclic aromatic hydrocarbons

Zeng Wen; Ma Hong-an

2011-02-01T23:59:59.000Z

426

Direct Numerical Simulation of Evaporative Cooling at the Lateral Boundary of Shallow Cumulus Clouds  

Science Conference Proceedings (OSTI)

This study investigates the dynamics of the subsiding shell at the lateral boundary of cumulus clouds, focusing on the role of evaporative cooling. Since the size of this shell is well below what large-eddy simulations can resolve, the authors ...

Dick Abma; Thijs Heus; Juan Pedro Mellado

2013-07-01T23:59:59.000Z

427

Numerical Simulations of the Effects of Seamounts and Vertical Resolution on Strong Ocean Flows  

Science Conference Proceedings (OSTI)

The effect of seamounts on Gulf Stream-like flow is examined using a quasi-geostrophic modal model that is spun-up from rest with idealized wind forcing. A flat-bottom simulation that resolves the flow with two vertical modes produces, on the ...

David Adamec

1988-02-01T23:59:59.000Z

428

Evaluation of numerical strategies for large eddy simulation of particulate two-phase recirculating flows  

Science Conference Proceedings (OSTI)

Predicting particle dispersion in recirculating two-phase flows is a key issue for reacting flows and a potential application of large eddy simulation (LES) methods. In this study, Euler/Euler and Euler/Lagrange LES approaches are compared in the bluff ... Keywords: Euler/Euler, Euler/Lagrange, LES, Particles, Two-phase recirculating flows

E. Riber; V. Moureau; M. Garca; T. Poinsot; O. Simonin

2009-01-01T23:59:59.000Z

429

Numerical Simulations of the Role of Land Surface Conditions in the Evolution and Structure of Summertime Thunderstorms over a Flat Highland  

Science Conference Proceedings (OSTI)

Numerical simulations of summertime thunderstorms over a flat highland (4700 m MSL), assuming the central Tibetan Plateau, were conducted with the use of a cloud-resolving nonhydrostatic model. This study was aimed at clarifying the role of land ...

Hiroyuki Yamada

2008-01-01T23:59:59.000Z

430

South Foehn in the Wipp Valley on 24 October 1999 (MAP IOP 10): Verification of High-Resolution Numerical Simulations with Observations  

Science Conference Proceedings (OSTI)

A case study of a south foehn windstorm observed across the Brenner Pass in the Wipp Valley near the AustrianItalian border is presented based on a detailed comparison and verification of high-resolution numerical simulations with observations. ...

Alexander Gohm; Gnther Zngl; Georg J. Mayr

2004-01-01T23:59:59.000Z

431

The Numerical Simulation of an Unbalanced Jetlet and Its Role in the Palm Sunday 1994 Tornado Outbreak in Alabama and Georgia  

Science Conference Proceedings (OSTI)

Meso-beta-scale numerical model simulations and observational data are synthesized in an effort to develop a multistage paradigm for use in forecasting tornadic convection in the southeastern United States. The case study to be utilized as an ...

Michael L. Kaplan; Yuh-Lang Lin; David W. Hamilton; Robert A. Rozumalski

1998-08-01T23:59:59.000Z

432

Origins of Aircraft-Damaging Clear-Air Turbulence during the 9 December 1992 Colorado Downslope Windstorm: Numerical Simulations and Comparison with Observations  

Science Conference Proceedings (OSTI)

Results from numerical simulations of the Colorado Front Range downslope windstorm of 9 December 1992 are presented. Although this case was not characterized by severe surface winds, the event caused extreme clear-air turbulence (CAT) aloft, as ...

Terry L. Clark; William D. Hall; Robert M. Kerr; Don Middleton; Larry Radke; F. Martin Ralph; Paul J. Neiman; David Levinson

2000-04-01T23:59:59.000Z

433

Four-Dimensional Assimilation of Multitime Wind Profiles over a Single Station and Numerical Simulation of a Mesoscale Convective System Observed during IHOP_2002  

Science Conference Proceedings (OSTI)

This study examines the impact of assimilating multitime wind profiles over a single station on the numerical simulation of a warm season mesoscale convective system over the region from the Kansas and Oklahoma border to the Texas Panhandle, ...

Lei Zhang; Zhaoxia Pu

2011-11-01T23:59:59.000Z

434

Numerical Simulation of Groundwater Withdrawal within the Mercury Valley Administrative Groundwater Basin, Nevada  

SciTech Connect

A detailed, transient, three-dimensional, finite-difference groundwater flow model was created for the Mercury Valley Administrative Groundwater Basin (MVB). The MVB is a distinct groundwater basin as defined by the State of Nevada and is located partially within the boundary of the Nevada Test Site. This basin is being studied as a potential location for new industrial facilities and therefore would be subject to Nevada water-use limitations. The MVB model was used to estimate the volume of water that could be withdrawn from Mercury Valley without inducing laterally or vertically extensive water-table effects. In each model simulation, water-table drawdown was limited to a maximum of 0.5 m at the boundary of the basin and held within the screened interval of the well. Water withdrawal from Nevada groundwater basins is also limited to the State-defined perennial yield for that area. The perennial yield for the MVB is 27,036 m{sup 3}/day. The one existing water-supply well in Mercury Valley is capable of sustaining significantly higher withdrawal rates than it currently produces. Simulations showed this single well could produce 50 percent of the basin?s perennial yield with limited water-table drawdown. Pumping from six hypothetical water-supply wells was also simulated. Each hypothetical well was placed in an area of high hydraulic conductivity and far from the basin's boundaries. Each of these wells was capable of producing at least 50 percent of the basin's perennial yield. One of the hypothetical wells could simulate 100 percent of the perennial yield while staying within drawdown limitations. Multi-well simulations where two or more water-supply wells were simultaneously pumping were also conducted. These simulations almost always resulted in very limited lateral and vertical drawdown and produced 100 percent of Mercury Valley's perennial yield. A water-budget analysis was also conducted for each of the various stress simulations. Each of the stress scenarios was compared to a baseline scenario where existing water-supply wells in the model domain were pumped at 2003-2004 average pumping rates. Water-budget analyses showed increased flow from the constant-head boundaries on the north, east, and west sides of the model. Flow to the southern, head-dependent boundary and to springs in the Ash Meadows area remained unchanged.

A.B. Gilliam; R.W.H. Carroll; G. Pohll; R.L. Hershey

2006-01-01T23:59:59.000Z

435

Knowledge representations for the automatic generation of numerical simulators for PDEs  

Science Conference Proceedings (OSTI)

In this paper we describe an automatic programming (AP) system which generates numerical discretization schemes for partial differential equation (PDE) problems. This system is based on the observation that a wide variety of discretization schemes can be mechanically produced by computing surface integrals of spacetime currents. However, surface integration is difficult to carry out using conventional vector calculus. For this reason, the system is structured to include the differential geometry formalisms which make high dimensional surface integration simple. The differential geometry formalisms have also simplified the representation of continuous physics problems and increased the domain of applicability of the system. 10 refs., 1 fig., 3 tabs.

Balaban, D.; Garbarini, J.; Greiman, W.; Durst, M. (Lawrence Livermore National Lab., CA (USA); Lawrence Berkeley Lab., CA (USA); Lawrence Livermore National Lab., CA (USA))

1989-02-21T23:59:59.000Z

436

Inverse Load Calculation of Wind Turbine Support Structures - A Numerical Verification Using the Comprehensive Simulation Code FAST: Preprint (Revised)  

DOE Green Energy (OSTI)

Physically measuring the dynamic responses of wind turbine support structures enables the calculation of the applied loads using an inverse procedure. In this process, inverse means deriving the inputs/forces from the outputs/responses. This paper presents results of a numerical verification of such an inverse load calculation. For this verification, the comprehensive simulation code FAST is used. FAST accounts for the coupled dynamics of wind inflow, aerodynamics, elasticity and turbine controls. Simulations are run using a 5-MW onshore wind turbine model with a tubular tower. Both the applied loads due to the instantaneous wind field and the resulting system responses are known from the simulations. Using the system responses as inputs to the inverse calculation, the applied loads are calculated, which in this case are the rotor thrust forces. These forces are compared to the rotor thrust forces known from the FAST simulations. The results of these comparisons are presented to assess the accuracy of the inverse calculation. To study the influences of turbine controls, load cases in normal operation between cut-in and rated wind speed, near rated wind speed and between rated and cut-out wind speed are chosen. The presented study shows that the inverse load calculation is capable of computing very good estimates of the rotor thrust. The accuracy of the inverse calculation does not depend on the control activity of the wind turbine.

Pahn, T.; Jonkman, J.; Rolges, R.; Robertson, A.

2012-11-01T23:59:59.000Z

437

MagmaHeatNS1D: One-dimensional visualization numerical simulator for computing thermal evolution in a contact metamorphic aureole  

Science Conference Proceedings (OSTI)

MagmaHeatNS1D is an IDL (Interactive Data Language) program that is aimed at numerically modeling heat transfer from an igneous intrusion to its host rocks and providing important thermal state information for minerals and organic matters in a contact ... Keywords: Contact metamorphism, Heat transfer model, Igneous intrusion, Maturation, Numerical simulation, Thermal evolution

Dayong Wang

2013-04-01T23:59:59.000Z

438

Numerical simulation of high-speed penetration-perforation dynamics in layered armor shields  

E-Print Network (OSTI)

Penetration models and calculating algorithms are presented, describing the dynamics and fracture of composite armor shields penetrated by high-speed small arms. A shield considered consists of hard (metal or ceramic) facing and multilayered fabric backing. A simple formula is proved for the projectile residual velocity after perforation of a thin facing. A new plastic-flow jet model is proposed for calculating penetration dynamics in the case of a thick facing of ceramic or metal-ceramic FGM materials. By bringing together the developed models into a calculating algorithm, a computer tool is designed enabling simulations of penetration processes in the above-mentioned shields and analysis of optimization problems. Some results of computer simulation are presented. It is revealed in particular that strength proof of pliable backing can be better as compared with more rigid backing. Comparison of calculations and test data shows sufficient applicability of the models and the tool.

Ayzenberg-Stepanenko, Mark

2012-01-01T23:59:59.000Z

439

Numerical simulation of high-speed penetration-perforation dynamics in layered armor shields  

E-Print Network (OSTI)

Penetration models and calculating algorithms are presented, describing the dynamics and fracture of composite armor shields penetrated by high-speed small arms. A shield considered consists of hard (metal or ceramic) facing and multilayered fabric backing. A simple formula is proved for the projectile residual velocity after perforation of a thin facing. A new plastic-flow jet model is proposed for calculating penetration dynamics in the case of a thick facing of ceramic or metal-ceramic FGM materials. By bringing together the developed models into a calculating algorithm, a computer tool is designed enabling simulations of penetration processes in the above-mentioned shields and analysis of optimization problems. Some results of computer simulation are presented. It is revealed in particular that strength proof of pliable backing can be better as compared with more rigid backing. Comparison of calculations and test data shows sufficient applicability of the models and the tool.

Mark Ayzenberg-Stepanenko; Grigory Osharovich

2012-03-07T23:59:59.000Z

440

Numerical simulations of collisionless drift instabilities for low-density plasmas  

SciTech Connect

Nonlinear behavior of the collisionless drift instabilities are studied for the universal and current driven modes by means of electrostatic particle simulations in two-and-a-half dimensions. Realistic mass ratios of the electrons to the ions are used in the simulations, where the guiding-center approximation for the electrons and the exact dynamics for the ions are employed. Several nonlinear effects including the quasilinear diffusion of the particle density, the frequency shift due to the ambipolar field, the mode competition among the unstable waves, and the quasilinear diffusion in the velocity space are found to be the dominant mechanisms for the saturation. The stabilization of the collisionless drift instabilities by the magnetic shear has also been studied.

Lee, W.W.; Yau, Y.Y.K.; Okuda, H.

1977-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "modeling-computer simulations numerical" 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

The Importance of the Entropy Inequality on Numerical Simulations Using Reduced Methane-air Reaction Mechanisms  

E-Print Network (OSTI)

Many reaction mechanisms have been developed over the past few decades to predict flame characteristics. A detailed reaction mechanism can predict flame characteristics well, but at a high computational cost. The reason for reducing reaction mechanisms is to reduce the computational time needed to simulate a problem. The focus of this work is on the validity of reduced methane-air combustion mechanisms, particularly pertaining to satisfying the entropy inequality. While much of this work involves a two-step reaction mechanism developed by Dr. Charles Westbrook and Dr. Frederick Dryer, some consideration is given to the four-step and three-step mechanisms of Dr. Norbert Peters. These mechanisms are used to simulate the Flame A experiment from Sandia National Laboratories. The two-step mechanism of Westbrook and Dryer is found to generate results that violate the entropy inequality. Modifications are made to the two-step mechanism simulation in an effort to reduce these violations. Two new mechanisms, Mech 1 and Mech 2, are developed from the original two-step reaction mechanism by modifying the empirical data constants in the Arrhenius reaction form. The reaction exponents are set to the stoichiometric coefficients of the reaction, and the concentrations computed from a one-dimensional flame simulation are matched by changing the Arrhenius parameters. The new mechanisms match experimental data more closely than the original two-step mechanism and result in a significant reduction in entropy inequality violations. The solution from Mech 1 had only 9 cells that violated the entropy inequality, while the original two-step mechanism of Westbrook and Dryer had 22,016 cells that violated the entropy inequality. The solution from Mech 2 did not have entropy inequality violations. The method used herein for developing the new mechanisms can be applied to more complex reaction mechanisms.

Jones, Nathan

2012-08-01T23:59:59.000Z

442

Numerical simulation of self-induced rainout using a dynamic convective cloud model  

Science Conference Proceedings (OSTI)

The hypothesis that self-induced rainout can occur is supported by observations in Hiroshima and Nagasaki, where deposition of weapons debris with precipitation occurred several km downwind of the burst point. This precipitation was initiated either directly by the nuclear weapons or by the ensuing fires. Simulation of the Nagasaki event with a convection cloud precipitation scavenging model, although fraught with many questionable assumptions, agrees surprisingly well with the observations and supports the hypothesis that self-induced rainout can occur.

Molenkamp, C.R.

1980-03-01T23:59:59.000Z

443

Coalescence kinetics in surfactant stabilized emulsions: Evolution equations from direct numerical simulations  

Science Conference Proceedings (OSTI)

Lattice Boltzmann simulations were used to study the coalescence kinetics in emulsions with amphiphilic surfactant, under neutrally buoyant conditions, and with a significant kinematic viscosity contrast between the phases (emulating water in oil emulsions). The 3D simulation domain was large enough (256 3rd power -- 10 7th power grid points) to obtain good statistics with droplet numbers ranging from a few thousand at early times to a few hundred near equilibrium. Increased surfactant contents slowed down the coalescence rate between droplets due to the Gibbs-Marangoni effect, and the coalescence was driven by a quasi-turbulent velocity field. The kinetic energy decayed at a relatively slow rate at early times, due to conversion of interfacial energy to kinetic energy in the flow during coalescence. Phenomenological, coupled differential equations for the mean droplet diameter D(t) and the number density nd(t) were obtained from the simulation data and from film draining theories. Local (in time) power law exponents for the growth of the mean diameter (and for the concomitant decrease of nd) were established in terms of the instantaneous values of the kinetic energy, coalescence probability, Gibbs elasticity, and interfacial area. The model studies indicated that true power laws for the growth of the droplet size and decrease of the number of droplets with time may not be justified, since the exponents derived using the phenomenological model were time dependent. In contrast to earlier simulation results for symmetric blends with surfactant, we found no evidence for stretched logarithmic scaling of the formD -- [ln (ct)]a for the morphology length, or exponential scalings associated with arrested growth, on the basis of the phenomenological model.

R. Skartlien; E. Sollum; A. Akselsen; P. Meakin; B. Grimes; J. Sjoblom

2012-12-01T23:59:59.000Z

444

Final Report: A Model Management System for Numerical Simulations of Subsurface Processes  

SciTech Connect

The DOE and several other Federal agencies have committed significant resources to support the development of a large number of mathematical models for studying subsurface science problems such as groundwater flow, fate of contaminants and carbon sequestration, to mention only a few. This project provides new tools to help decision makers and stakeholders in subsurface science related problems to select an appropriate set of simulation models for a given field application.

Zachmann, David

2013-10-07T23:59:59.000Z

445

Methane Hydrate Dissociation by Depressurization in a Mount Elbert Sandstone Sample: Experimental Observations and Numerical Simulations  

SciTech Connect

A preserved sample of hydrate-bearing sandstone from the Mount Elbert Test Well was dissociated by depressurization while monitoring the internal temperature of the sample in two locations and the density changes at high spatial resolution using x-ray CT scanning. The sample contained two distinct regions having different porosity and grain size distributions. The hydrate dissociation occurred initially throughout the sample as a result of depressing the pressure below the stability pressure. This initial stage reduced the temperature to the equilibrium point, which was maintained above the ice point. After that, dissociation occurred from the outside in as a result of heat transfer from the controlled temperature bath surrounding the pressure vessel. Numerical modeling of the test using TOUGH+HYDRATE yielded a gas production curve that closely matches the experimentally measured curve.

Kneafsey, T.; Moridis, G.J.

2011-01-15T23:59:59.000Z

446

NUMERICAL SIMULATION FOR MECHANICAL BEHAVIOR OF U10MO MONOLITHIC MINIPLATES FOR RESEARCH AND TEST REACTORS  

Science Conference Proceedings (OSTI)

This article presents assessment of the mechanical behavior of U-10wt% Mo (U10Mo) alloy based monolithic fuel plates subject to irradiation. Monolithic, plate-type fuel is a new fuel form being developed for research and test reactors to achieve higher uranium densities within the reactor core to allow the use of low-enriched uranium fuel in high-performance reactors. Identification of the stress/strain characteristics is important for understanding the in-reactor performance of these plate-type fuels. For this work, three distinct cases were considered: (1) fabrication induced residual stresses (2) thermal cycling of fabricated plates; and finally (3) transient mechanical behavior under actual operating conditions. Because the temperatures approach the melting temperature of the cladding during the fabrication and thermal cycling, high temperature material properties were incorporated to improve the accuracy. Once residual stress fields due to fabrication process were identified, solution was used as initial state for the subsequent simulations. For thermal cycling simulation, elasto-plastic material model with thermal creep was constructed and residual stresses caused by the fabrication process were included. For in-service simulation, coupled fluid-thermal-structural interaction was considered. First, temperature field on the plates was calculated and this field was used to compute the thermal stresses. For time dependent mechanical behavior, thermal creep of cladding, volumetric swelling and fission induced creep of the fuel foil were considered. The analysis showed that the stresses evolve very rapidly in the reactor. While swelling of the foil increases the stress of the foil, irradiation induced creep causes stress relaxation.

Hakan Ozaltun & Herman Shen

2011-11-01T23:59:59.000Z

447

Numerical simulation of bump-on-tail instability with source and sink  

Science Conference Proceedings (OSTI)

This paper presents results of the simulations of the bump-on-tail instability with a weak source and sink. This problem has been posed as a paradigm for the important problem in controlled fusion, that of the unstable excitation of Alfven waves in a tokamak by resonant energetic alpha particles. The source of alpha particles is the controlled fusion reaction produced by the background plasma and the sink is the collisional transport processes that slow down or scatter the energetic particles. The mathematical techniques that are needed to address this applied problem can be demonstrated in the much simpler bump-on-tail problem, which is explained in this paper.

Berk, H.L.; Pekker, M. [Texas Univ., Austin, TX (United States). Inst. for Fusion Studies; Breizman, B.N. [Texas Univ., Austin, TX (United States). Inst. for Fusion Studies]|[Budker Inst. of Nuclear Physics, Novosibirsk (Russian Federation)

1995-02-01T23:59:59.000Z

448

Numerical simulation of whistler-triggered VLF emissions observed in Antartica  

SciTech Connect

The authors have extracted from VLF databases from British Antarctica Survey data taken at Halley and Faraday stations, examples of whistler-triggered emissions (WTE). The WTE are relatively narrow band emissions triggered by natural background whistlers undergoing nonlinear wave particle interactions generally in the equatorial regions. They occur with either rising or falling frequency relative to the triggering waves. Using a Vlasov type code the authors are able to simulate the types of emissions which are observed. 24 refs., 8 figs., 3 tabs.

Nunn, D. [Southhampton Univ., Southhampton (United Kingdom); Smith, A.J. [British Antarctic Survey, Cambridge (United Kingdom)

1996-03-01T23:59:59.000Z

449

Numerical Simulation of Earth Pressure on Head Chamber of Shield Machine with FEM  

SciTech Connect

Model parameters of conditioned soils in head chamber of shield machine are determined based on tree-axial compression tests in laboratory. The loads acting on tunneling face are estimated according to static earth pressure principle. Based on Duncan-Chang nonlinear elastic constitutive model, the earth pressures on head chamber of shield machine are simulated in different aperture ratio cases for rotating cutterhead of shield machine. Relationship between pressure transportation factor and aperture ratio of shield machine is proposed by using aggression analysis.

Li Shouju; Kang Chengang [State Key Laboratory of structural analysis for industrial equipment, Dalian University of Technology, Dalian 116023 (China); Sun, Wei [School of Mechanical Engineering, Dalian University of Technology, Dalian 116023 (China); Shangguan Zichang [School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116023 (China); Institute of Civil Engineering, Dalian Fishery University, Dalian 116023 (China)

2010-05-21T23:59:59.000Z

450

Numerical Simulation of Squeeze Film Dampers and Study of the Effect of Central Groove on the Dynamic Pressure Distribution  

E-Print Network (OSTI)

Squeeze film dampers are used in the high speed turbo machinery industry and aerospace industries as a means to reduce vibration amplitude, to provide damping, to improve dynamic stability of the rotor bearing system and to isolate structural components. The effects of cavitation included in previous studies were not effective. The effect of different design parameters were not studied thoroughly as experimental investigation of squeeze film dampers is very expensive. Few of them used numerical investigation but the methods they used are either time consuming or complicated. The present study investigated the feasibility of applying a steady state solver, which is computationally less expensive, for analyzing flow field inside the squeeze film dampers. The behavior of dynamic pressure profiles at different operating conditions, and the effect of a central groove on dynamic pressure profiles were also studied. Simulation results of a 3D case which is similar to the one experimentally studied by Delgado were used to establish if the moving reference frame (MRF) model in Fluent 12.1 can be used. A steady state solver in an absolute frame of reference was used to produce whirling motion of the rotor in this study. The inlet pressure of 31kpa and the whirling speed of 50 and 100Hz were used as boundary conditions. The mixture model with three percent dissolved air in lubricant is used to model multiphase flow. Singhal cavitation model is used to model cavitation. The simulations (50,000 iterations) were run until steady state solutions were reached. The results closely agreed with those obtained experimentally by San Andrs and Delgado. Numerical simulations of three-dimensional cases with an additional central groove on the squeeze film land were also performed to predict the effect of central groove on dynamic pressure profiles. Addition central groove reduces the pressures and forces generated by squeeze film damper.

Boppa, Praneetha

2011-08-01T23:59:59.000Z

451

Numerical simulation of thin-shell direct drive DHe3-filled capsules fielded at OMEGA  

Science Conference Proceedings (OSTI)

Thin-shell deuterium-helium-3 (DHe{sup 3}) filled glass capsules on the Omega laser provide a fast-implosion experimental platform for developing separate time-resolved measurements of ion, electron, and radiation temperatures in nonequilibrium plasmas. Dynamically significant non-local thermodynamic equilibrium (NLTE) conditions are created by the addition of xenon dopant to the DHe{sup 3} gas fill, in quantities sufficient to have an impact on yields, compression, and cooling rates. The high-Z dopant dramatically increases the radiative cooling rate in the plasma, allowing it to collapse in compressions that can be an order of magnitude higher than in undoped capsules. A baseline LASNEX simulation model using detailed configuration accounting NLTE atomic physics shows very good agreement with the data for doped as well as undoped capsules, while other models either underpredict or overpredict the radiative cooling enhancement. The baseline model captures the behavior of the capsule when the D:He{sup 3} ratio is varied well away from equimolar, suggesting no yield anomaly with either nearly pure deuterium or He{sup 3} fills. Variation of the electron-ion coupling in the baseline simulation model shows agreement with the data for a coupling multiplier that is within 20% of unity. Reliably inferring electron-ion coupling strength from the data is complicated by uncertainties in the hydrodynamic mix and other parameters, but many of these can be mitigated in follow-on experiments at the National Ignition Facility.

Miles, A. R.; Chung, H.-K.; Heeter, R.; Hsing, W.; Koch, J. A.; Park, H.-S.; Robey, H. F.; Scott, H. A.; Tommasini, R. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Frenje, J.; Li, C. K.; Petrasso, R. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Glebov, V. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Lee, R. W. [SLAC Linear Coherent Light Source, Menlo Park, California 94025 (United States)

2012-07-15T23:59:59.000Z

452

A High-Resolution Modeling Study of the 24 May 2002 Dryline Case during IHOP. Part I: Numerical Simulation and General Evolution of the Dryline and Convection  

Science Conference Proceedings (OSTI)

Results from a high-resolution numerical simulation of the 24 May 2002 dryline convective initiation (CI) case are presented. The simulation uses a 400 km 700 km domain with a 1-km horizontal resolution grid nested inside a 3-km domain and ...

Ming Xue; William J. Martin

2006-01-01T23:59:59.000Z

453

Non-linear numerical simulations of magneto-acoustic wave propagation in small-scale flux tubes  

E-Print Network (OSTI)

We present results of non-linear, 2D, numerical simulations of magneto-acoustic wave propagation in the photosphere and chromosphere of small-scale flux tubes with internal structure. Waves with realistic periods of three to five minutes are studied, after applying horizontal and vertical oscillatory perturbations to the equilibrium model. Spurious reflections of shock waves from the upper boundary are minimized thanks to a special boundary condition. This has allowed us to increase the duration of the simulations and to make it long enough to perform a statistical analysis of oscillations. The simulations show that deep horizontal motions of the flux tube generate a slow (magnetic) mode and a surface mode. These modes are efficiently transformed into a slow (acoustic) mode in the vA < cS atmosphere. The slow (acoustic) mode propagates vertically along the field lines, forms shocks and remains always within the flux tube. It might deposit effectively the energy of the driver into the chromosphere. When the driver oscillates with a high frequency, above the cut-off, non-linear wave propagation occurs with the same dominant driver period at all heights. At low frequencies, below the cut-off, the dominant period of oscillations changes with height from that of the driver in the photosphere to its first harmonic (half period) in the chromosphere. Depending on the period and on the type of the driver, different shock patterns are observed.

E. Khomenko; M. Collados; T. Felipe

2007-10-17T23:59:59.000Z

454

Two-dimensional numerical simulation of a Stirling engine heat exchanger  

DOE Green Energy (OSTI)

This paper describes the first phase of an effort to develop multidimensional models of Stirling engine components; the ultimate goal is to model an entire engine working space. More specifically, this paper describes parallel plate and tubular heat exchanger models with emphasis on the central part of the channel (i.e., ignoring hydrodynamic and thermal end effects). The model assumes: Laminar, incompressible flow with constant thermophysical properties. In addition, a constant axial temperature gradient is imposed. The governing equations, describing the model, have been solved Crack-Nicloson finite-difference scheme. Model predictions have been compared with analytical solutions for oscillating/reversing flow and heat transfer in order to check numerical accuracy. The simplifying assumptions will later be relaxed to permit modeling of incompressible, laminar/turbulent flow that occurs in Stirling heat exchanger. Excellent agreement has been obtained for the model predictions with analytical solutions available for both flow in circular tubes and between parallel plates. Also the heat transfer computational results are in good agreement with the heat transfer analytical results for parallel plates.

Ibrahim, M.B. [Cleveland State Univ., OH (United States); Tew, R.C.; Dudenhoefer, J.E. [Lewis Research Center, Cleveland, OH (United States)

1994-09-01T23:59:59.000Z

455

Numerical simulation of ECRIPAC plasma behaviour with Vlasov equations including electron and ion collective effects  

E-Print Network (OSTI)

ECKIPAC is a new ion-electron accelerator concept using IXX, GYRAC and IUS4I~E effects, which is being studied in a collaboration betweeii (EA/l~KI;M ~ (Grenoble), INS (Saclay) and GANII * ((am). A 611 Vlasov code using the particle method was dcvelopped to simulate the electron heating process, the plasma compression and the energy transfer from electrons to ions. Two versions are available: the first one allows a precise description of the plasma during small time intervals, at different stages of the process. The second corresponds to an adiabatic approximation of electron motions, where electron superparticles are replaced hy circles obemg special equations coupled with collective effects. Exlernal electromagnetic fields depending on x, y, 7 rind t are accurately computed. while collective fields are calculated using the cloud in cell scheme.

P. Bertrand

2012-01-01T23:59:59.000Z

456

A preliminary evaluation of the performance of wind tunnel and numerical modeling simulations of the wind flow over a wind farm  

SciTech Connect

This report is an analysis of physical and numerical model simulations of the wind flow over complex terrain. The specific area to which these models were applied is a wind farm in the Altamont Pass area of California. The physical model results were obtained from wind tunnel flow simulations, and the numerical model used was the optimizing version of the NOABL model. The goals of this analysis were (1) to evaluate the relative performance of the two models and (2) to uncover any clues that would point toward improvement of the wind tunnel modeling. The performances of the models were gauged by comparing model simulations to wind observations taken over the modeled area.

Barnard, J.C.; Wegley, H.L.

1987-01-01T23:59:59.000Z

457

VINE-A NUMERICAL CODE FOR SIMULATING ASTROPHYSICAL SYSTEMS USING PARTICLES. II. IMPLEMENTATION AND PERFORMANCE CHARACTERISTICS  

Science Conference Proceedings (OSTI)

We continue our presentation of VINE. In this paper, we begin with a description of relevant architectural properties of the serial and shared memory parallel computers on which VINE is intended to run, and describe their influences on the design of the code itself. We continue with a detailed description of a number of optimizations made to the layout of the particle data in memory and to our implementation of a binary tree used to access that data for use in gravitational force calculations and searches for smoothed particle hydrodynamics (SPH) neighbor particles. We describe the modifications to the code necessary to obtain forces efficiently from special purpose 'GRAPE' hardware, the interfaces required to allow transparent substitution of those forces in the code instead of those obtained from the tree, and the modifications necessary to use both tree and GRAPE together as a fused GRAPE/tree combination. We conclude with an extensive series of performance tests, which demonstrate that the code can be run efficiently and without modification in serial on small workstations or in parallel using the OpenMP compiler directives on large-scale, shared memory parallel machines. We analyze the effects of the code optimizations and estimate that they improve its overall performance by more than an order of magnitude over that obtained by many other tree codes. Scaled parallel performance of the gravity and SPH calculations, together the most costly components of most simulations, is nearly linear up to at least 120 processors on moderate sized test problems using the Origin 3000 architecture, and to the maximum machine sizes available to us on several other architectures. At similar accuracy, performance of VINE, used in GRAPE-tree mode, is approximately a factor 2 slower than that of VINE, used in host-only mode. Further optimizations of the GRAPE/host communications could improve the speed by as much as a factor of 3, but have not yet been implemented in VINE. Finally, we find that although parallel performance on small problems may reach a plateau beyond which more processors bring no additional speedup, performance never decreases, a factor important for running large simulations on many processors with individual time steps, where only a small fraction of the total particles require updates at any given moment.

Nelson, Andrew F. [Los Alamos National Laboratory, HPC-5, MS B272, Los Alamos, NM 87545 (United States); Wetzstein, M. [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Naab, T. [Universitaets-Sternwarte, Scheinerstr. 1, 81679 Muenchen (Germany)], E-mail: andy.nelson@lanl.gov

2009-10-01T23:59:59.000Z

458

Numerical simulation of the plasma current quench following a disruptive energy loss  

SciTech Connect

The plasma electromagnetic interaction with poloidal field coils and nearby passive conductor loops during the current quench following a disruptive loss of plasma energy is simulated. By solving a differential/algebraic system consisting of a set of circuit equations (including the plasma circuit) coupled to a plasma energy balance equation and an equilibrium condition, the electromagnetic consequences of an abrupt thermal quench are observed. Limiters on the small and large major radium sides of the plasma are assumed to define the plasma cross section. The presence of good conductors near the plasma and a small initial distance (i.e., 5 to 10% of the plasma minor radius) between the plasma edge and an inboard limiter are shown to lead to long current decay times. For a plasma with an initial major radius R/sub o/ = 4.3 m, aspect ratio A = 3.6, and current I/sub P/ = 4.0 MA, introducing nearby passive conductors lengthens the current decay from milliseconds to hundreds of milliseconds.

Strickler, D.J.; Peng, Y.K.M.; Holmes, J.A.; Miller, J.B.; Rothe, K.E.

1983-11-01T23:59:59.000Z

459

Laser Ion Acceleration Toward Future Ion Beam Cancer Therapy - Numerical Simulation Sudy-  

E-Print Network (OSTI)

Ion beam has been used in cancer treatment, and has a unique preferable feature to deposit its main energy inside a human body so that cancer cell could be killed by the ion beam. However, conventional ion accelerator tends to be huge in its size and its cost. In this paper a future intense-laser ion accelerator is proposed to make the ion accelerator compact. An intense femtosecond pulsed laser was employed to accelerate ions. The issues in the laser ion accelerator include the energy efficiency from the laser to the ions, the ion beam collimation, the ion energy spectrum control, the ion beam bunching and the ion particle energy control. In the study particle computer simulations were performed to solve the issues, and each component was designed to control the ion beam quality. When an intense laser illuminates a target, electrons in the target are accelerated and leave from the target; temporarily a strong electric field is formed between the high-energy electrons and the target ions, and the target ions ...

Kawata, Shigeo; Nagashima, Toshihiro; Takano, Masahiro; Barada, Daisuke; Kong, Qing; Gu, Yan Jun; Wang, Ping Xiao; Ma, Yan Yun; Wang, Wei Ming

2013-01-01T23:59:59.000Z

460

IC-EpsMsO NUMERICAL SIMULATION IN VERTICAL WIND AXIS TURBINE WITH PITCH  

E-Print Network (OSTI)

energy, pitch controlled blades Abstract: Wind energy is more and more used as a renewable energy source character. The present wind turbine is a small one which allows to be used on roofs or in gardens to light small areas like publicity boards, parking, roads or for water pumping, heating... The present turbine has a vertical axis. Each turbine blade combines a rotating movement around its own axis and around the main rotor axis. Due to this combination of movements, flow around this turbine is highly unsteady and needs to be modeled by unsteady calculation. One of the main problems of such geometry is to simulate the two combined movements. The present work is an extended study of ones made in 2009. In the previous study, some results like contours of pressure and velocity fields were presented for elliptic blades for one specific constant rotational speed and benefits of combined rotating blades was shown. The present paper points up the influence of two different blades geometries for different rotational speeds, different blade stagger angles and different Reynolds numbers related to a wider range of wind speeds. 1

Controlled Blades; Bayeul-lain Annie-claude; Dockter Aurore; Bois Grard; Simonet Sophie

2013-01-01T23:59:59.000Z

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461

Numerical simulations and predictive models of undrained penetration in soft soils  

E-Print Network (OSTI)

There are two aspects in this study: cylinder penetrations and XBP (Expendable Bottom Penetrometer) interpretations. The cylinder studies firstly investigate the relationship between the soil resisting force and penetration depth by a series of rateindependent finite element analyses of pre-embedded penetration depths, and validate the results by upper and lower bound solutions from classical plasticity theory. Furthermore, strain rate effects are modeled by finite element simulations within a framework of rate-dependent plasticity. With all forces acting on the cylinder estimated, penetration depths are predicted from simple equations of motion for a single particle. Comparisons to experimental results show reasonable agreement between model predictions and measurements. The XBP studies follow the same methodology in investigating the soil shearing resistance as a function of penetration depth and velocity by finite element analyses. With the measurements of time decelerations during penetration of the XBP, sediment shear strength profile is inferred from a single particle kinetic model. The predictions compare favorably with experimental measurements by vane shear tests.

Shi, Han

2005-08-01T23:59:59.000Z

462

Direct Numerical Simulation of Reionization II: Recombinations, Clumping Factors, and the Photon Budget for Reionization  

E-Print Network (OSTI)

In this first of several application papers, we investigate the mechanics of reionization from stellar sources in high-z galaxies, the utility of various clumping factors on estimating the recombination time in the IGM, and the photon budget required to achieve reionization. We test the accuracy of the static and time-dependent models of Madau et al. as predictors of reionization completion/maintenance. We simulate a WMAP7 LCDM cosmological model in a 20 Mpc comoving cube with 800^3 uniform fluid cells and dark matter particles. By tuning our star formation to approximately match the observed star formation rate density and luminosity function, we created a fully coupled radiation-hydro realization of H reionization which begins to ionize at z~10 and completes at z~5.8. We find that roughly 2 ionizing photons per H atom are required to convert the neutral IGM to a highly ionized state, which supports the "photon starved" scenario discussed by Bolton & Haehnelt. The events during reionization that lead to ...

So, Geoffrey C; Reynolds, Daniel R; Harkness, Robert P

2013-01-01T23:59:59.000Z

463

Direct numerical simulations of type Ia supernovae flames II: The Rayleigh-Taylor instability  

Science Conference Proceedings (OSTI)

A Type Ia supernova explosion likely begins as a nuclear runaway near the center of a carbon-oxygen white dwarf. The outward propagating flame is unstable to the Landau-Darrieus, Rayleigh-Taylor, and Kelvin-Helmholtz instabilities, which serve to accelerate it to a large fraction of the speed of sound. We investigate the Rayleigh-Taylor unstable flame at the transition from the flamelet regime to the distributed-burning regime, around densities of 10e7 gm/cc, through detailed, fully resolved simulations. A low Mach number, adaptive mesh hydrodynamics code is used to achieve the necessary resolution and long time scales. As the density is varied, we see a fundamental change in the character of the burning--at the low end of the density range the Rayleigh-Taylor instability dominates the burning, whereas at the high end the burning suppresses the instability. In all cases, significant acceleration of the flame is observed, limited only by the size of the domain we are able to study. We discuss the implications of these results on the potential for a deflagration to detonation transition.

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

2004-01-12T23:59:59.000Z

464

The Effect of Gas Absorption on the Scattered Radiation in the Solar Almucantar: Results of Numerical Simulation  

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

Gas Absorption on the Gas Absorption on the Scattered Radiation in the Solar Almucantar: Results of Numerical Simulation T. Yu. Chesnokova, K. M. Firsov, I. M. Nasrtdinov, S. M. Sakerin, V. V. Veretennikov, and T. B. Zhuravleva Institute of Atmospheric Optics Tomsk, Russia Introduction The methods for reconstruction of the aerosol optical characteristics (e.g., aerosol size distribution, and single-scattering albedo) from diffuse and direct radiation measured in the solar almucantar has been widely used during the last decade. The photometers with filters in the "atmospheric transparency windows" in the wavelength range 0.4 to 1 m were applied for measurements. Usually it was assumed that one could neglect the molecular absorption of the measured diffuse radiation. Further development

465

2004 Initial Assessments for the T and TX TY Tank Farm Field Investigation Report (FIR): Numerical Simulations  

SciTech Connect

In support of CH2M HILL Hanford Group, Inc.s (CHG) preparation of a Field Investigative Report (FIR) for the Hanford Site Single-Shell Tank Waste Management Area (WMA) T and TX-TY, a suite of numerical simulations of flow and solute transport was executed using the STOMP code to predict the performance of surface barriers for reducing long-term risks from potential groundwater contamination at the T and TX-TY WMA. The scope and parametric data for these simulations were defined by a modeling data package provided by CHG. This report documents the simulation involving 2-D cross sections through the T Tank and the TX-TY Tank Farm. Eight cases were carried out for the cross sections to simulate the effects of interim barrier, water line leak, inventory distribution, and surface recharge on water flow and the transport of long-lived radionuclides (i.e., technecium-99 and uranium) and chemicals (i.e., nitrate and chromium For simulations with barriers, it is assumed that an interim barrier is in place by the year 2010. It was also assumed that, for all simulations, as part of tank farm closure, a closure barrier was in place by the year 2040. The modeling considers the estimated inventories of contaminants within the vadose zone and calculates the associated risk. It assumes that no tanks will leak in the future. Initial conditions for contaminant concentration are provided as part of inventory estimates for uranium, technetium-99, nitrate, and chromium. For moisture flow modeling, Neumann boundary conditions are prescribed at the surface with the flux equal to the recharge rate estimate. For transport modeling, a zero flux boundary is prescribed at the surface for uranium, technetium-99, nitrate, and chromium. The western and eastern boundaries are assigned no-flux boundaries for both flow and transport. The water table boundary is prescribed by water table elevations and the unconfined aquifer hydraulic gradient. No-flux boundaries are used for the lower boundary. Numerical results were obtained for compliance at the WMA boundary, 200 Areas boundary, exclusion boundary beyond the 200 Areas, and the Columbia River (DOE-RL 2000). Streamtube/analytical models were used to route computed contaminant concentrations at the water table to the downstream compliance points. When the interim barrier was applied at 2010, the soil was desaturated gradually. The difference in saturation of the soil with and without the interim barrier was the largest at 2040, the time the closure barrier was applied. After this, the difference in saturation in the two cases became smaller with time. Generally, the solutes broke though faster if there was a water line leak. A relative small five-day leak (Case 4) had little effect on the peak concentration, while a large 20-yr leak (Case 3) increased the peak concentration significantly and reduced the solute travel in the vadose zone. The distribution of the inventory, either uniform or nonuniform, has little effect on peak arrival time; the peak concentrations of the conservative solutes varied by -6.9 to 0.2% for the T tank farm and by 11 to 49.4% for the TX tank farm. The reduction of the meteoric recharge before the barrier was applied led to less soil saturation, as expected, and thus longer solute travel time in the vadose zone and smaller peak fence line concentration. The effect on soil saturation lasted for about another 50 years after the barrier was applied at 2050. However, the reduced recharge rate affected the breakthough curve till the end of the simulation. The fence line concentrations at the year 3000 were always higher for cases with reduced natural recharge than for those of the base case, which indicates that the fundamental impact of the reduced natural recharge is a smoothing of the breakthrough concentrations at the compliance points.

Zhang, Z. F.; Freedman, Vicky L.; Waichler, Scott R.

2004-09-24T23:59:59.000Z

466

Numerical Simulation of Injectivity Effects of Mineral Scaling and Clay Swelling in a Fractured Geothermal Reservoir  

DOE Green Energy (OSTI)

A major concern in the development of hot dry rock (HDR) and hot fractured rock (HFR) reservoirs is achieving and maintaining adequate injectivity, while avoiding the development of preferential short-circuiting flow paths such as those caused by thermally-induced stress cracking. Past analyses of HDR and HFR reservoirs have tended to focus primarily on the coupling between hydrology (flow), heat transfer, and rock mechanics. Recent studies suggest that rock-fluid interactions and associated mineral dissolution and precipitation effects could have a major impact on the long-term performance of HFR reservoirs. The present paper uses recent European studies as a starting point to explore chemically-induced effects of fluid circulation in HFR systems. We examine ways in which the chemical composition of reinjected waters can be modified to improve reservoir performance by maintaining or even enhancing injectivity. Chemical manipulations considered here include pH modification and dilution with fresh water. We performed coupled thermo-hydrologic-chemical simulations in which the fractured medium was represented by a one-dimensional MINC model (multiple interacting continua), using the non-isothermal multi-phase reactive geochemical transport code TOUGHREACT. Results indicate that modifying the injection water chemistry can enhance mineral dissolution and reduce clay swelling. Chemical interactions between rocks and fluids will change a HFR reservoir over time, with some changes favorable and others not. A detailed, quantitative understanding of processes and mechanisms can suggest chemical methods for reservoir management, which may be employed to improve the performance of the geothermal system.

Xu, Tianfu; Pruess, Karsten

2004-05-10T23:59:59.000Z

467

FOUR-FLUID MODEL AND NUMERICAL SIMULATIONS OF MAGNETIC STRUCTURES IN THE HELIOSHEATH  

Science Conference Proceedings (OSTI)

The first part of this paper extends the three-fluid model of Avinash and Zank for magnetic structures in the heliosheath to a four-fluid model consisting of electrons, pick-up ions (PUIs), solar wind ions (SWIs), and neutral hydrogen. The PUIs are generated by neutrals via charge exchange with SWI. Since the kinetic pressure of PUI is nearly three to four times the pressure of SWI, these are more suited to mediate small-scale structures in the heliosheath such as magnetic holes (MH)/humps etc. The constant energy exchange between these two fluids drives them nonadiabatic. The PUIs are isothermal ({gamma} = 1) while SWIs are nonadiabatic with an index {gamma} {approx} 1.25. The four-fluid model captures these effects via a modified equation of state for PUI and SWI. The phase space of time-independent solutions in terms of the Mach numbers of PUI and SWI is constructed to delineate the parameter space which allows structure formation in the heliosheath. The second part of the paper examines the stability of the time-independent solutions computed in the first part by evolving them via a full system of Hall-MHD equations. The simulation results show that these solutions are not quite stable. As the structure propagates it develops growing oscillations in the wings. Concomitantly, there are changes in the amplitude and width of the structure. This instability could be due to local changes in the velocity of the structure and reflects an exchange between the kinetic and magnetic parts of the total energy. Our results about the presence of growing oscillations in the wings of solitary wave solutions are consistent with the recent analysis of MHs in the heliosheth by Burlaga et al. Their analysis also shows evidence for the presence of oscillations and instabilities in the wings of MHs in the heliosheath.

Avinash, K. [Department of Physics and Astrophysics, University of Delhi, 110007, India. (India); Cox, Sean M.; Shaikh, Dastgeer; Zank, G. P. [Centre for Space Plasma and Aeronomic Research, University of Alabama, Hunstville, AL 35899 (United States)

2009-04-10T23:59:59.000Z

468

Numerical Simulation of a Displacement Ventilation System with Multi-heat Sources and Analysis of Influential Factors  

E-Print Network (OSTI)

Displacement ventilation (DV) is a promising ventilation concept due to its high ventilation efficiency. In this paper, the application of the CFD method, the velocity and temperature fields of three-dimensional displacement ventilation systems with double heat sources are numerically simulated. The model is verified by experimental data. The results of the study show that thermal stratification characteristics exist in indoor temperature fields. The paper also analyzes the influence of different influential factors, e.g., the distance between heat sources, temperature of heat source, heat characteristics of the wall and outdoor temperature. It was found that the human requirement for comfort is satisfied easily when the distance between heat sources is long. Under the conditions simulated in this paper, when the distance was more than 0.8m, the temperature distribution tended to be average and steady, and it did not change as the distance changed. Second, the temperature change of the thermal current has a large influence on the indoor temperature. The rise in thermal current temperature makes the vertical temperature gradient in the room increase. The upper temperature of the room becomes higher, as does the height of the high temperature air level that lies in the upper part of the room. Finally, both the heat loss of the surrounding structure and the change in outdoor temperature have a large influence on indoor temperature. However, it does not influence the thermal stratification characteristics of DV. The only thing that has changed is the thermal stratification height.

Wu, X.; Gao, J.; Wu, W.

2006-01-01T23:59:59.000Z

469

ROLE OF MAGNETIC FIELD STRENGTH AND NUMERICAL RESOLUTION IN SIMULATIONS OF THE HEAT-FLUX-DRIVEN BUOYANCY INSTABILITY  

SciTech Connect

The role played by magnetic fields in the intracluster medium (ICM) of galaxy clusters is complex. The weakly collisional nature of the ICM leads to thermal conduction that is channeled along field lines. This anisotropic heat conduction profoundly changes the instabilities of the ICM atmosphere, with convective stabilities being driven by temperature gradients of either sign. Here, we employ the Athena magnetohydrodynamic code to investigate the local non-linear behavior of the heat-flux-driven buoyancy instability (HBI) relevant in the cores of cooling-core clusters where the temperature increases with radius. We study a grid of two-dimensional simulations that span a large range of initial magnetic field strengths and numerical resolutions. For very weak initial fields, we recover the previously known result that the HBI wraps the field in the horizontal direction, thereby shutting off the heat flux. However, we find that simulations that begin with intermediate initial field strengths have a qualitatively different behavior, forming HBI-stable filaments that resist field-line wrapping and enable sustained vertical conductive heat flux at a level of 10%-25% of the Spitzer value. While astrophysical conclusions regarding the role of conduction in cooling cores require detailed global models, our local study proves that systems dominated by the HBI do not necessarily quench the conductive heat flux.

Avara, Mark J.; Reynolds, Christopher S. [Department of Astronomy, University of Maryland, College Park, MD 20740 (United States); Bogdanovic, Tamara, E-mail: mavara@astro.umd.edu, E-mail: chris@astro.umd.edu, E-mail: tamarab@gatech.edu [Center for Relativistic Astrophysics, School of Physics, Georgia Tech, Atlanta, GA 30332 (United States)

2013-08-20T23:59:59.000Z

470

An analysis of lower-dimensional approximations to the scalar dissipation rate using direct numerical simulations of plane jet flames  

SciTech Connect

The difficulty of experimental measurements of the scalar dissipation rate in turbulent flames has required researchers to estimate the true three-dimensional (3D) scalar dissipation rate from one-dimensional (1D) or two-dimensional (2D) gradient measurements. In doing so, some relationship must be assumed between the true values and their lower dimensional approximations. We develop these relationships by assuming a form for the statistics of the gradient vector orientation, which enables several new results to be obtained and the true 3D scalar dissipation PDF to be reconstructed from the lower-dimensional approximations. We use direct numerical simulations (DNS) of turbulent plane jet flames to examine the orientation statistics, and verify our assumptions and final results. We develop and validate new theoretical relationships between the lower-dimensional and true moments of the scalar dissipation PDF assuming a log-normal true PDF. We compare PDFs reconstructed from lower-dimensional gradient projections with the true values and find an excellent agreement for a 2D simulated measurement and also for a 1D simulated measurement perpendicular to the mean flow variations. Comparisons of PDFs of thermal dissipation from DNS with those obtained via reconstruction from 2D experimental measurements show a very close match, indicating this PDF is not unique to a particular flame configuration. We develop a technique to reconstruct the joint PDF of the scalar dissipation and any other scalar, such as chemical species or temperature. Reconstructed conditional means of the hydroxyl mass fraction are compared with the true values and an excellent agreement is obtained.

Chen, Jackie [Sandia National Laboratories (SNL); Sankaran, Ramanan [ORNL; Hawkes, Evatt R [Sandia National Laboratories (SNL)

2009-05-01T23:59:59.000Z

471

CAPE-OPEN compliant stochastic modeling and reduced-order model computation capability for APECS system  

Science Conference Proceedings (OSTI)

APECS (Advanced Process Engineering Co-Simulator) is an integrated software suite that combines the power of process simulation with high-fidelity, computational fluid dynamics (CFD) for improved design, analysis, and optimization of process engineering systems. The APECS system uses commercial process simulation (e.g., Aspen Plus) and CFD (e.g., FLUENT) software integrated with the process-industry standard CAPE-OPEN (CO) interfaces. This breakthrough capability allows engineers to better understand and optimize the fluid mechanics that drive overall power plant performance and efficiency. The focus of this paper is the CAPE-OPEN complaint stochastic modeling and reduced order model computational capability around the APECS system. The usefulness of capabilities is illustrated with coal fired, gasification based, FutureGen power plant simulation. These capabilities are used to generate efficient reduced order models and optimizing model complexities.

Diwekar, Urmila (Vishwamitra Research Institute, Clarendon Hills, IL); Shastri, Yogendra (Vishwamitra Research Institute Clarendon Hills, IL); Subrmanyan, Karthik (Vishwamitra Research Institute, Clarendon Hills, IL); Zitney, S.E.

2007-11-04T23:59:59.000Z

472

The deposition and burning characteristics during slagging co-firing coal and wood: modeling and numerical simulation  

SciTech Connect

Numerical analysis was used to study the deposition and burning characteristics of combining co-combustion with slagging combustion technologies in this paper. The pyrolysis and burning kinetic models of different fuels were implanted into the WBSF-PCC2 (wall burning and slag flow in pulverized co-combustion) computation code, and then the slagging and co-combustion characteristics (especially the wall burning mechanism of different solid fuels and their effects on the whole burning behavior in the cylindrical combustor at different mixing ratios under the condition of keeping the heat input same) were simulated numerically. The results showed that adding wood powder at 25% mass fraction can increase the temperature at the initial stage of combustion, which is helpful to utilize the front space of the combustor. Adding wood powder at a 25% mass fraction can increase the reaction rate at the initial combustion stage; also, the coal ignitability is improved, and the burnout efficiency is enhanced by about 5% of suspension and deposition particles, which is helpful for coal particles to burn entirely and for combustion devices to minimize their dimensions or sizes. The results also showed that adding wood powder at a proper ratio is helpful to keep the combustion stability, not only because of the enhancement for the burning characteristics, but also because the running slag layer structure can be changed more continuously, which is very important for avoiding the abnormal slag accumulation in the slagging combustor. The theoretic analysis in this paper proves that unification of co-combustion and slagging combustion technologies is feasible, though more comprehensive and rigorous research is needed.

Wang, X.H.; Zhao, D.Q.; Jiang, L.Q.; Yang, W.B. [Chinese Academy of Sciences, Ghangzhou (China)

2009-07-01T23:59:59.000Z

473

An investigation of the effect of pore scale flow on average geochemical reaction rates using direct numerical simulation  

Science Conference Proceedings (OSTI)

The scale-dependence of geochemical reaction rates hinders their use in continuum scale models intended for the interpretation and prediction of chemical fate and transport in subsurface environments such as those considered for geologic sequestration of CO{sub 2}. Processes that take place at the pore scale, especially those involving mass transport limitations to reactive surfaces, may contribute to the discrepancy commonly observed between laboratory-determined and continuum-scale or field rates. Here, the dependence of mineral dissolution rates on the pore structure of the porous media is investigated by means of pore scale modeling of flow and multicomponent reactive transport. The pore scale model is comprised of high performance simulation tools and algorithms for incompressible flow and conservative transport combined with a general-purpose multicomponent geochemical reaction code. The model performs direct numerical simulation of reactive transport based on an operator-splitting approach to coupling transport and reactions. The approach is validated with a Poiseuille flow single-pore experiment and verified with an equivalent 1D continuum-scale model of a capillary tube packed with calcite spheres. Using the case of calcite dissolution as an example, the high resolution model is used to demonstrate that non-uniformity in the flow field at the pore scale has the effect of decreasing the overall reactivity of the system, even when systems with identical reactive surface area are considered. The effect becomes more pronounced as the heterogeneity of the reactive grain packing increases, particularly where the flow slows sufficiently such that the solution approaches equilibrium locally and the average rate becomes transport-limited.

Rafa, S. Molins; Trebotich, D.; Steefel, C. I.; Shen, C.

2012-02-01T23:59:59.000Z

474

Numerical Simulation Management  

Science Conference Proceedings (OSTI)

... API. A high level API is required for customizing the management process when the SMT requirements do not meet the researcher's needs. ...

2013-07-19T23:59:59.000Z

475

The introduction of the microchanneling phenomenon to cyclic steam stimulation and its application to the numerical simulator (sand deformation concept)  

SciTech Connect

Historically, a vertical or horizontal fracture is believed to be a main recovery mechanism for a cyclic steam-injection process in unconsolidated oil sands. Most current computer models for the process are based on the fracture concept. With the postulated sand deformation concept, on the other hand, the injected fluid is able to penetrate the unconsolidated oil sand by creating microchannels. When the pore pressure is reduced during production, these secondary flow channels will collapse totally or partially. Condensed steam tends to sweep fluids where the bitumen had been heated and imparts mobility as a result of the injected hot fluid. Flow geometry of the new concept is described in this paper. The physical differences between the sand deformation zone and the no-deformation zone are also investigated. The three major differences between these two zones are porosity change, pressure level, and energy and flow characteristics resulting from the existence of microchannels. All these modifications were incorporated successfully into a conventional numerical thermal simulator. The new model provided an excellent match for all the field observations (steam-injection pressure, oil-and-water production rates, fluid production temperature, downhole production pressure, and salinity changes) of a steam-stimulated well in an unconsolidated oil sand. The study indicates that the most important phenomenon for in-situ recovery of bitumen is the one-way-valve effect of the microchannels, which are opened during injection and closed during production.

Ito, Y.

1984-08-01T23:59:59.000Z

476

J. Plasma Fusion Res. SERIES, Vol. 8 (2009) Numerical Simulation of an Explosively Driven HVDC Circuit Breaker  

E-Print Network (OSTI)

High Voltage Direct Current (HVDC) circuit breakers have to suppress high values of currents at high voltages in absence of current-zero points. This makes the arc interruption more severe than the case of conventional AC networks. For circuit breaking in HVDC networks, a capacitor-inductor set has been inserted in parallel with the circuit breaker to inject reverse current to the interruption chamber and create the artificial current-zero points. In this paper, a novel method for reverse current injection has been proposed in which a high current pulsed power source (Helical Flux Compression Generator) has been employed to generate the opposing current. Numerical simulation of high-current arc in case of HVDC circuit breakers has been presented. For this purpose, the MHD equations describing the behavior of the DC arcs are jointed to the circuit equations of Flux Compression Generator which is coupled to a simple HVDC network. The results indicate that the explosively driven current injection set can make the current-zero point properly and lead to successful interruption of DC current consequently. This method needs much less volume and cost in comparison with the parallel capacitor-inductor sets.

Jouya Jadidian; Kaveh Niayesh; Ehsan Hashemi; Edris Agheb; Amir A. Shayegani

2008-01-01T23:59:59.000Z

477

Original article: Numerical simulation of two-phase flow in deformable porous media: Application to carbon dioxide storage in the subsurface  

Science Conference Proceedings (OSTI)

In this paper, conceptual modeling as well as numerical simulation of two-phase flow in deep, deformable geological formations induced by CO"2 injection are presented. The conceptual approach is based on balance equations for mass, momentum and energy ... Keywords: Carbon capture storage (CCS), Heat transport, OpenGeoSys (OGS), Porous media, Two-phase flow consolidation

O. Kolditz; S. Bauer; N. BTtcher; D. Elsworth; U. -J. GRke; C. -I. Mcdermott; C. -H. Park; A. K. Singh; J. Taron; W. Wang

2012-06-01T23:59:59.000Z

478

Proceedings of Institute of Mathematics of NAS of Ukraine 2004, Vol. 50, Part 3, 13901395 Numerical Simulation of Replacing Oil by Water  

E-Print Network (OSTI)

­1395 Numerical Simulation of Replacing Oil by Water in a Scale-Invariant Porous Medium Ekaterina P. KUROCHKINA with 2563 grid in spatial variables. 1 Introduction The interface of oil displaced by water is unstable a significant influence on the transport of water and oil. The permeability heterogenei- ty is often identified

Popovych, Roman

479

Numerical simulations of the Macondo well blowout reveal strong control of oil flow by reservoir permeability and exsolution of gas  

E-Print Network (OSTI)

for estimates of the oil and gas flow rate from the Macondoteam and carried out oil and gas flow simulations using theoil-gas system. The flow of oil and gas was simulated using

Oldenburg, C.M.

2013-01-01T23:59:59.000Z

480

Mesoscale Numerical Weather Prediction Models Used in Support of Infrared Hyperspectral Measurement Simulation and Product Algorithm Development  

Science Conference Proceedings (OSTI)

A novel application of numerical weather prediction (NWP) models within an end-to-end processing system used to demonstrate advanced hyperspectral satellite technologies and instrument concepts is presented. As part of this system, sophisticated ...

Jason A. Otkin; Derek J. Posselt; Erik R. Olson; Hung-Lung Huang; James E. Davies; Jun Li; Christopher S. Velden

2007-04-01T23:59:59.000Z

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481

The Interaction between Baroclinic and Diabatic Processes in a Numerical Simulation of a Rapidly Intensifying Extratropical Marine Cyclone  

Science Conference Proceedings (OSTI)

This study addresses the relative contributions of adiabatic baroclinic and diabatic processes and their interaction in the evolution of a rapidly intensifying marine cyclone. Two numerical experiments were performed using a limited-area ...

Ying-Hwa Kuo; M. A. Shapiro; Evelyn G. Donall

1991-02-01T23:59:59.000Z

482

Dynamics of Air Pollution Transport in Late Wintertime over Kathmandu Valley, Nepal: As Revealed with Numerical Simulation  

Science Conference Proceedings (OSTI)

Air pollution characteristics over the Kathmandu Valley in wintertime were numerically investigated by using a comprehensive transportchemistrydeposition model of air pollutants together with the fifth-generation Pennsylvania State University...

Toshihiro Kitada; Ram P. Regmi

2003-12-01T23:59:59.000Z

483

Long-term simulation of turbulence-induced loads using the SNLWIND-3D, FAST, YawDyn, and ADAMS numerical codes  

DOE Green Energy (OSTI)

Notable progress was made in simulating the dynamic response of operating wind turbines during the past several years. In concert with these activities, the ability to adequately simulate the characteristics of the turbulent inflow, which is directly or indirectly responsible for much of the observed response, has also improved significantly. Recent investigations have shown that without such inflow simulations, it is often difficult to predict fatigue-load distributions that agree with observations. In this paper we discuss the results of a numerical experiment in which we simulated representative diurnal variations in the inflow environments for two distinct locations within a multi-row wind farm: upwind of the first and downwind of the last row of turbines. With the SNLWIND-3D turbulence simulation code, we created a series of 144, 10-minute inflow records that are likely to occur individually within a 24-hour period at each location. An upwind, rigid-hub, three-bladed turbine was modeled with the Yaw Dynamics (YawDyn) and Automatic Dynamic Analysis of Mechanical Systems (ADAMS) simulation codes while a downwind, teetered-hub, two-bladed turbine was simulated with the Fatigue, Aerodynamics, Structures, and Turbulence (FAST) code and ADAMS. We found good to excellent agreement between the codes themselves in predicting the flapwise bending load spectra, and with limited test data.

Kelley, N.D.; Wright, A.D.; Buhl, M.L. Jr.; Tangler, J.L.

1996-10-01T23:59:59.000Z

484

Short communication: A GIS-based decision support system for integrated flood management under uncertainty with two dimensional numerical simulations  

Science Conference Proceedings (OSTI)

A new decision support system has been developed for integrated flood management within the framework of ArcGIS based on realistic two dimensional flood simulations. This system has the ability to interact with and use classified Remote Sensing (RS) ... Keywords: 2D simulation, ArcGIS, Census block, Decision support system, Integrated flood management, Remote sensing

Honghai Qi; M. S. Altinakar

2011-06-01T23:59:59.000Z

485

Testing the accuracy of the Hydro-PM approximation in numerical simulations of the Lyman-alpha forest  

E-Print Network (OSTI)

We implement the hydro-PM (HPM) technique (Gnedin & Hui 1998) in the hydrodynamical simulation code GADGET-II and quantify the differences between this approximate method and full hydrodynamical simulations of the Lyman-alpha forest in a concordance LCDM model. At redshifts z=3 and z=4, the differences between the gas and dark matter (DM) distributions, as measured by the one-point distribution of density fluctuations, the density power spectrum and the flux power spectrum, systematically decrease with increasing resolution of the HPM simulqation. However, reducing these differences to less than a few percent requires a significantly larger number of grid-cells than particles, with a correspondingly larger demand for memory. Significant differences in the flux decrement distribution remain even for very high resolution hydro-PM simulations, particularly at low redshift. At z=2, the differences between the flux power spectra obtained from HPM simulations and full hydrodynamical simulations are generally la...

Viel, M; Springel, V; Viel, Matteo; Haehnelt, Martin G.; Springel, Volker

2006-01-01T23:59:59.000Z

486

A Three-Dimensional Numerical Simulation of Hudson Bay Summer Ocean Circulation: Topographic Gyres, Separations, and Coastal Jets  

Science Conference Proceedings (OSTI)

The summer ocean circulation in Hudson Bay is studied numerically using the Blumberg-Mellor model with a 27.5 km 27.5 km horizontal grid and a realistic bottom topography. In the control run 1) monthly climatological forcing fields of wind ...

Jia Wang; Lawrence A. Mysak; R. Grant Ingram

1994-12-01T23:59:59.000Z

487

NUMERICAL DETERMINATION AND TREATMENT OF CONVECTIVE HEAT TRANSFER COEFFICIENT IN THE COUPLED BUILDING ENERGY AND CFD SIMULATION  

E-Print Network (OSTI)

for the correct prediction of the convective heat. A finer grid resolution in CFD does not always lead to a m