National Library of Energy BETA

Sample records for mesoscale convective systems

  1. MESOSCALE CONVECTIVE SYSTEMS Robert A. Houze Jr.

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    MESOSCALE CONVECTIVE SYSTEMS Robert A. Houze Jr. Department of Atmospheric Sciences University; published 31 December 2004. [1] Mesoscale convective systems (MCSs) have regions of both convective and stratiform precipitation, and they develop mesoscale circulations as they mature. The upward motion takes

  2. Observational Analysis of the Predictability of Mesoscale Convective Systems ISRAEL L. JIRAK AND WILLIAM R. COTTON

    E-Print Network [OSTI]

    Observational Analysis of the Predictability of Mesoscale Convective Systems ISRAEL L. JIRAK (Manuscript received 30 December 2005, in final form 4 October 2006) ABSTRACT Mesoscale convective systems of usefulness in operational forecasting. 1. Introduction Mesoscale convective systems (MCSs) frequently de

  3. Charge rearrangement by sprites over a north Texas mesoscale convective system

    E-Print Network [OSTI]

    Cummer, Steven A.

    Charge rearrangement by sprites over a north Texas mesoscale convective system William W. Hager,1 is analyzed for a mesoscale convective system (MCS) situated in north Texas and east New Mexico on 15 July. Lapierre (2012), Charge rearrangement by sprites over a north Texas mesoscale convective system, J. Geophys

  4. THE ROLE OF CLOUD MICROPHYSICS PARAMETERIZATION IN THE SIMULATION OF MESOSCALE CONVECTIVE SYSTEMS AND ANVIL

    E-Print Network [OSTI]

    THE ROLE OF CLOUD MICROPHYSICS PARAMETERIZATION IN THE SIMULATION OF MESOSCALE CONVECTIVE SYSTEMS in the Simulation of Mesoscale Convective Systems and Anvil Clouds in the Tropical Western Pacific K. Van Weverberg1 cloud microphysics in the simulation of mesoscale convective systems (MCSs) in the tropical western

  5. Transient luminous events above two mesoscale convective systems: Charge moment change analysis

    E-Print Network [OSTI]

    Cummer, Steven A.

    Transient luminous events above two mesoscale convective systems: Charge moment change analysis. A. Rutledge, and D. R. MacGorman (2011), Transient luminous events above two mesoscale convective in the stratiform region of a mesoscale convective system (MCS) [Houze et al., 1990] by energetic positive CG (+CG

  6. Thermodynamic properties of mesoscale convective systems observed during BAMEX

    SciTech Connect (OSTI)

    Correia, James; Arritt, R.

    2008-11-01

    Dropsonde observations from the Bow-echo and Mesoscale convective vortex EXperiment (BAMEX) are used to document the spatio-temporal variability of temperature, moisture and wind within mesoscale convective systems (MCSs). Onion type sounding structures are found throughout the stratiform region of MCSs but the temperature and moisture variability is large. Composite soundings were constructed and statistics of thermodynamic variability were generated within each sub-region of the MCS. The calculated air vertical velocity helped identify subsaturated downdrafts. We found that lapse rates within the cold pool varied markedly throughout the MCS. Layered wet bulb potential temperature profiles seem to indicate that air within the lowest several km comes from a variety of source regions. We also found that lapse rate transitions across the 0 C level were more common than isothermal, melting layers. We discuss the implications these findings have and how they can be used to validate future high resolution numerical simulations of MCSs.

  7. The effect of shear on heat budgets in a simulated Mesoscale Convective System 

    E-Print Network [OSTI]

    Shaw, Justin David

    2000-01-01

    The evolution and structure of simulated Mesoscale Convective Systems (MCS) were examined using the Collaborative Model for Multiscale Atmospheric Simulations. Three numerical simulations were performed, with the amount ...

  8. Vertical profiles of radar reflectivity of convective cells in tropical and mid-latitude mesoscale convective systems 

    E-Print Network [OSTI]

    Lutz, Kurt Reed

    1992-01-01

    VERTICAL PROFILES OF RADAR REFLECTIVITY OF CONVECTIVE CELLS IN TROPICAL AND MID-LATITUDE MESOSCALE CONVECTIVE SYSTEMS A Thesis by KURT REED LUTZ Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 1992 Major Subject: Meteorology VERTICAL PROFILES OF RADAR REFLECTIVITY OF CONVECTIVE CELLS IN TROPICAL AND MID-LATITUDE MESOSCALE CONVECTIVE SYSTEMS A Thesis by KURT REED LUTZ Approved...

  9. October 1986 R. H. Johnson 721 Lower-Tropospheric Warming and Drying in Tropical Mesoscale Convective Systems

    E-Print Network [OSTI]

    Johnson, Richard H.

    October 1986 R. H. Johnson 721 Lower-Tropospheric Warming and Drying in Tropical Mesoscale components of tropical mesoscale convective systems. It is found that while the apparent heat source Q1 of mesoscale downdrafts within the mesoscale convective systems. The warming and drying at low levels

  10. Charge transfer and in-cloud structure of large-charge-moment positive lightning strokes in a mesoscale convective system

    E-Print Network [OSTI]

    Cummer, Steven A.

    in a mesoscale convective system Gaopeng Lu,1 Steven A. Cummer,1 Jingbo Li,1 Feng Han,1 Richard J. Blakeslee,2 positive cloud-to-ground (+CG) strokes in a mesoscale convective system. Although no high altitude images of large-charge-moment positive lightning strokes in a mesoscale convective system, Geophys. Res. Lett., 36

  11. Urban and land surface effects on the 30 July 2003 mesoscale convective system event observed in the southern Great Plains

    E-Print Network [OSTI]

    Niyogi, Dev

    Urban and land surface effects on the 30 July 2003 mesoscale convective system event observed/Atmosphere Mesoscale Prediction System (COAMPS 1 ) to investigate the impact of urban and land vegetation processes on the prediction of the mesoscale convective system (MCS) observed on 30 July 2003 in the vicinity of Oklahoma City

  12. Observations of prolific transient luminous event production above a mesoscale convective system in Argentina during

    E-Print Network [OSTI]

    Cummer, Steven A.

    in Argentina during the Sprite2006 Campaign in Brazil F. T. São Sabbas,1 M. J. Taylor,2 P.D. Pautet,2 M. Bailey convective system (MCS) over Argentina, as part of the third sprite campaign in Brazil. GOES infrared (IR a mesoscale convective system in Argentina during the Sprite2006 Campaign in Brazil, J. Geophys. Res., 115, A

  13. On the effect of the steady-state approximation in time-space composite studies of mesoscale convective systems 

    E-Print Network [OSTI]

    Mattison, Kevin Morgan

    1992-01-01

    ON THE EFFECT OF THE STRA 'Y-STATE APPROXIMATION IN TIME-SPACE COMPOSITE STUDIES OF MESOSCALE CONVECTIVE SYSTEMS A Thesis KEVIN MORGAN MATTISON Subnitted to the Office of Graduate Studies of Texas A&M University in partial fulfillnent... Studies of Mesoscale Convective Systems. (December 1992) Kevin Morgan Mattison, A. Sc. , Community College of the Air Force; B. S. , Auburn University at Montgomery Chair of Advisory Committee: Dr. Michael I. Biggerstaff This study examined the effects...

  14. Mesoscale convective complex vs. non-mesoscale convective complex thunderstorms: a comparison of selected meteorological variables 

    E-Print Network [OSTI]

    Hoofard, Michael Eugene

    1986-01-01

    MESOSCALE CONVECTIVE CCMPLLX VS. NON-MESOSCALE CONVECTIVE COMPLEX THUNDERSTORMS: A COMPARISON OF SELECTED METEOROLOGICAL VARIABLES A Thesis MICHAkL EUGENE JJOOFARD Submitted to the Graduate College of Texas AJkM University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1986 Major Subj ect: Meteorology MESOSCALE CONVECTIVE COMPLEX VS. NON-MESOSCALE CONVECTIVE COMPLEX THUNDERSTORMS: A COMPARISON OF SELECTED METEOROLOGICAL VARIABLES A Thesis...

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

    E-Print Network [OSTI]

    Restivo, Michael Edward

    1995-01-01

    The TOGA COARE experiment was carried out in the western Pacific warm pool region from November 1992 through February 1993. Data from TOGA COARE provide the opportunity for comprehensive studies of tropical oceanic convection. ...

  16. Patterns of Precipitation and Mesolow Evolution in Midlatitude Mesoscale Convective Vortices

    E-Print Network [OSTI]

    Johnson, Richard H.

    Patterns of Precipitation and Mesolow Evolution in Midlatitude Mesoscale Convective Vortices ERIC P manifestations of mesoscale convective vortices (MCVs) that traversed Oklahoma during the periods May­August 2002 Profiler Network data. Forty-five MCVs that developed from mesoscale convective systems (MCSs) have been

  17. Analysis of 11 june 2003 mesoscale convective vortex genesis using weather surveillance radar ??88 doppler (wsr-88d) 

    E-Print Network [OSTI]

    Reynolds, Amber Elizabeth

    2009-05-15

    Mesoscale convective vortices (MCVs), which typically form within the stratiform rain of some mesoscale convective systems (MCSs), may persist for days, often regenerating convection daily. Long-lived MCVs can produce as much precipitation as a...

  18. On the Forecasting of Orogenic Mesoscale Convective Complexes

    E-Print Network [OSTI]

    Tucker, Donna F.; Zentmire, Kristine S.

    1999-12-01

    ., 1980: Mesoscale convective complexes. Bull. Amer. Meteor. Soc., 61, 1374–1387. , 1983: Large-scale meteorological conditions associated with midlatitude mesoscale convective complexes. Mon. Wea. Rev., 111, 1475–1493. , D. M. Rodgers, and K. W. Howard..., 1982: Mesoscale convective complexes over the United States during 1981—Annual sum- mary. Mon. Wea. Rev., 110, 1501–1514. , K. W. Howard, D. L. Bartels, and D. M. Rodgers, 1986: Me- soscale convective complexes in the middle latitudes. Mesoscale...

  19. The kinematic and cloud-to-ground lightning structure of the 9-10, June 1998 Red River Mesoscale Convective System 

    E-Print Network [OSTI]

    Santarpia, Joshua

    2001-01-01

    An investigation of the kinematic and electrical properties of the 9-10 June, 1998 Red River Mesoscale Convective System (MCS), as observed by the NOAA P3 Tail Radar and the National Lightning Detection Network, is presented. This system exhibits...

  20. MPO 663 -Convective and Mesoscale Meteorology Brian Mapes, Spring 2008

    E-Print Network [OSTI]

    Miami, University of

    MPO 663 - Convective and Mesoscale Meteorology Brian Mapes, Spring 2008 I intend for students and mesoscale phenomena. 2. Working understanding of several of these tools, cultivated via homework, including. A sense of how convective and mesoscale phenomena fit into larger scales, gained via short current

  1. Some Effects of Model Resolution on Simulated Gravity Waves Generated by Deep, Mesoscale Convection

    E-Print Network [OSTI]

    Knievel, Jason Clark

    Some Effects of Model Resolution on Simulated Gravity Waves Generated by Deep, Mesoscale Convection. Introduction Gravity waves generated by deep convective clouds play an important role in the momentum budget scales: short gravity waves generated by individual con- vective systems and cells on the meso- and meso

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

    E-Print Network [OSTI]

    Practical and Intrinsic Predictability of Severe and Convective Weather at the Mesoscales at the mesoscales using convection-permitting ensemble simulations of a squall line and bow echo event during the Bow Echo and Mesoscale Convective Vortex (MCV) Experiment (BAMEX) on 9­10 June 2003. Although most

  3. AcceptedArticleThe effect of moist convection on thermally induced mesoscale circulations

    E-Print Network [OSTI]

    Gentine, Pierre

    AcceptedArticleThe effect of moist convection on thermally induced mesoscale circulations Malte of thermally induced mesoscale circulations rests primarily on observations and model studies of dry convection-eddy simulations are used to investigate the effect of moist convection on an idealized mesoscale circulation

  4. A Climatology of Midlatitude Mesoscale Convective Vortices in the Rapid Update Cycle

    E-Print Network [OSTI]

    Johnson, Richard H.

    A Climatology of Midlatitude Mesoscale Convective Vortices in the Rapid Update Cycle ERIC P. JAMES of mesoscale convective vortices (MCVs) occurring in the state of Oklahoma during the late spring and summer, true MCVs represent only about 20% of the mesoscale relative vorticity maxima detected by the algorithm

  5. Analysis of Cloud-resolving Simulations of a Tropical Mesoscale Convective System Observed during TWP-ICE: Vertical Fluxes and Draft Properties in Convective and Stratiform Regions

    SciTech Connect (OSTI)

    Mrowiec, Agnieszka A.; Rio, Catherine; Fridlind, Ann; Ackerman, Andrew; Del Genio, Anthony D.; Pauluis, Olivier; Varble, Adam; Fan, Jiwen

    2012-10-02

    We analyze three cloud-resolving model simulations of a strong convective event observed during the TWP-ICE campaign, differing in dynamical core, microphysical scheme or both. Based on simulated and observed radar reflectivity, simulations roughly reproduce observed convective and stratiform precipitating areas. To identify the characteristics of convective and stratiform drafts that are difficult to observe but relevant to climate model parameterization, independent vertical wind speed thresholds are calculated to capture 90% of total convective and stratiform updraft and downdraft mass fluxes. Convective updrafts are fairly consistent across simulations (likely owing to fixed large-scale forcings and surface conditions), except that hydrometeor loadings differ substantially. Convective downdraft and stratiform updraft and downdraft mass fluxes vary notably below the melting level, but share similar vertically uniform draft velocities despite differing hydrometeor loadings. All identified convective and stratiform downdrafts contain precipitation below ~10 km and nearly all updrafts are cloudy above the melting level. Cold pool properties diverge substantially in a manner that is consistent with convective downdraft mass flux differences below the melting level. Despite differences in hydrometeor loadings and cold pool properties, convective updraft and downdraft mass fluxes are linearly correlated with convective area, the ratio of ice in downdrafts to that in updrafts is ~0.5 independent of species, and the ratio of downdraft to updraft mass flux is ~0.5-0.6, which may represent a minimum evaporation efficiency under moist conditions. Hydrometeor loading in stratiform regions is found to be a fraction of hydrometeor loading in convective regions that ranges from ~10% (graupel) to ~90% (cloud ice). These findings may lead to improved convection parameterizations.

  6. Elements of comparison between Martian and terrestrial mesoscale meteorological phenomena: Katabatic winds and boundary layer convection

    E-Print Network [OSTI]

    Spiga, Aymeric

    Elements of comparison between Martian and terrestrial mesoscale meteorological phenomena Keywords: Mesoscale meteorology Katabatic winds Boundary layer convection Comparative planetology a b s t r a c t Terrestrial and Martian atmospheres are both characterised by a large variety of mesoscale

  7. Modeling of passive microwave responses in convective situations using output from mesoscale models

    E-Print Network [OSTI]

    Pardo-Carrión, Juan R.

    Modeling of passive microwave responses in convective situations using output from mesoscale models using output from nonhydrostatic mesoscale atmospheric model, Meso-NH, simulations. The radiative for a systematic evaluation of the mesoscale cloud models. An overall good agreement is obtained for both

  8. Evolution of vertical drafts and cloud-to-ground lightning within the convective region of a mesoscale convective complex 

    E-Print Network [OSTI]

    Saul, Scott Henry

    1995-01-01

    The evolution of the area-averaged vertical velocity within the objectively defined convective region of the 4 June 1985 PRE-STORM (Preliminary Regional Experiment for Stormscale Operational and Research Meteorology-Central Phase) mesoscale...

  9. Use of ARM observations and numerical models to determine radiative and latent heating profiles of mesoscale convective systems for general circulation models

    SciTech Connect (OSTI)

    Tao, Wei-Kuo; Houze, Robert, A., Jr.; Zeng, Xiping

    2013-03-14

    This three-year project, in cooperation with Professor Bob Houze at University of Washington, has been successfully finished as planned. Both ARM (the Atmospheric Radiation Measurement Program) data and cloud-resolving model (CRM) simulations were used to identify the water budgets of clouds observed in two international field campaigns. The research results achieved shed light on several key processes of clouds in climate change (or general circulation models), which are summarized below. 1. Revealed the effect of mineral dust on mesoscale convective systems (MCSs) Two international field campaigns near a desert and a tropical coast provided unique data to drive and evaluate CRM simulations, which are TWP-ICE (the Tropical Warm Pool International Cloud Experiment) and AMMA (the African Monsoon Multidisciplinary Analysis). Studies of the two campaign data were contrasted, revealing that much mineral dust can bring about large MCSs via ice nucleation and clouds. This result was reported as a PI presentation in the 3rd ASR Science Team meeting held in Arlington, Virginia in March 2012. A paper on the studies was published in the Journal of the Atmospheric Sciences (Zeng et al. 2013). 2. Identified the effect of convective downdrafts on ice crystal concentration Using the large-scale forcing data from TWP-ICE, ARM-SGP (the Southern Great Plains) and other field campaigns, Goddard CRM simulations were carried out in comparison with radar and satellite observations. The comparison between model and observations revealed that convective downdrafts could increase ice crystal concentration by up to three or four orders, which is a key to quantitatively represent the indirect effects of ice nuclei, a kind of aerosol, on clouds and radiation in the Tropics. This result was published in the Journal of the Atmospheric Sciences (Zeng et al. 2011) and summarized in the DOE/ASR Research Highlights Summaries (see http://www.arm.gov/science/highlights/RMjY5/view). 3. Used radar observations to evaluate model simulations In cooperation with Profs. Bob Houze at University of Washington and Steven Rutledge at Colorado State University, numerical model results were evaluated with observations from W- and C-band radars and CloudSat/TRMM satellites. These studies exhibited some shortcomings of current numerical models, such as too little of thin anvil clouds, directing the future improvement of cloud microphysics parameterization in CRMs. Two papers of Powell et al (2012) and Zeng et al. (2013), summarizing these studies, were published in the Journal of the Atmospheric Sciences. 4. Analyzed the water budgets of MCSs Using ARM data from TWP-ICE, ARM-SGP and other field campaigns, the Goddard CRM simulations were carried out to analyze the water budgets of clouds from TWP-ICE and AMMA. The simulations generated a set of datasets on clouds and radiation, which are available http://cloud.gsfc.nasa.gov/. The cloud datasets were available for modelers and other researchers aiming to improve the representation of cloud processes in multi-scale modeling frameworks, GCMs and climate models. Special datasets, such as 3D cloud distributions every six minutes for TWP-ICE, were requested and generated for ARM/ASR investigators. Data server records show that 86,206 datasets were downloaded by 120 users between April of 2010 and January of 2012. 5. MMF simulations The Goddard MMF (multi-scale modeling framework) has been improved by coupling with the Goddard Land Information System (LIS) and the Goddard Earth Observing System Model, Version 5 (GOES5). It has also been optimized on NASA HEC supercomputers and can be run over 4000 CPUs. The improved MMF with high horizontal resolution (1 x 1 degree) is currently being applied to cases covering 2005 and 2006. The results show that the spatial distribution pattern of precipitation rate is well simulated by the MMF through comparisons with satellite retrievals from the CMOPRH and GPCP data sets. In addition, the MMF results were compared with three reanalyses (MERRA, ERA-Interim and CFSR). Although the MMF tends

  10. Nighttime atmospheric stability changes and their effects on the temporal intensity of a mesoscale convective complex 

    E-Print Network [OSTI]

    Hovis, Jeffrey Scott

    1988-01-01

    NIGHTTIME ATMOSPHERIC STABILITY CHANGES AND THEIR EFFECTS ON THE TEMPORAL INTENSITY OF A MESOSCALE CONVECTIVE COMPLEX A Thesis JEFFREY SCOTT HOVIS Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1988 Major Subject: Meteorology NIGHTTIME ATMOSPHERIC STABILITY CHANGES AND THEIR EFFECTS ON THE TEMPORAL INTENSITY OF A MESOSCALE CONVECTIVE COMPLEX A Thesis JEFFREY SCOTT HOVIS Approved as to style...

  11. Mesoscale environmental models accompanying convection in the Texas HIPLEX region / by Mark Edward Humbert 

    E-Print Network [OSTI]

    Humbert, Mark Edward

    1980-01-01

    MESOSCALE ENVIRONMENTAL MODELS ACCOMPANYING CONVECTION IN THE TEXAS HIPLEX REGION A Thesis by MARK EDWARD HUMBERT Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1980 Major Subject: Meteorology MESOSCALE ENVIRONMENTAL MODELS ACCOMPANYING CONVECTION IN THE TEXAS HIPLEX REGION A Thesis by MARK EDWARD HUMBERT Approved as to style and content by: (Chairman of Co ttee) (Head of Department) (Member...

  12. Mesoscale flows in large aspect ratio simulations of turbulent compressible convection

    E-Print Network [OSTI]

    F. Rincon; F. Lignieres; M. Rieutord

    2006-11-28

    We present the results of a very large aspect ratio (42.6) numerical simulation of fully compressible turbulent convection in a polytropic atmosphere, and focus on the properties of large-scale flows. Mesoscale patterns dominate the turbulent energy spectrum. We show that these structures, which had already been observed in Boussinesq simulations by Cattaneo et al. (2001), have a genuine convective origin and do not result directly from collective interactions of the smaller scales of the flow, even though their growth is strongly affected by nonlinear transfers. If this result is relevant to the solar photosphere, it suggests that the dominant convective mode below the Sun's surface may be at mesoscales.

  13. Generation of mesoscale convective structures in tokamak edge plasma

    SciTech Connect (OSTI)

    Krasheninnikov, S. I.; Smolyakov, A. I. [University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States); University of Saskatchewan, 116 Science Place, Saskatoon, Saskatchewan S7N 5E2 (Canada)

    2007-10-15

    It is shown that the interplay of the interchange drive and nonlinear effects of Reynolds stress and inverse cascade of drift wave turbulence select a range of plasma parameters (plasma pressure), for which mesoscale perturbations of a certain transverse length scale become unstable. It is suggested that the blob formation is a result of these mesoscale instabilities.

  14. Modeling of passive microwave responses in convective situations using output from mesoscale models

    E-Print Network [OSTI]

    Chaboureau, Jean-Pierre

    Modeling of passive microwave responses in convective situations using output from mesoscale models 2003; revised 27 January 2004; accepted 5 February 2004; published 30 March 2004. [1] Passive microwave, which essentially sense cloud tops. Therefore passive microwave observations are a very promising tool

  15. A case study of the mesoscale and synoptic-scale heat and moisture budgets in the vicinity of a mesoscale convective complex 

    E-Print Network [OSTI]

    Dial, Greg Leander

    1990-01-01

    A CASE STUDY OF THE MESOSCALE AND SYNOPTIC-SCALE HEAT AND MOISTURE BUDGETS IN THE VICINITY OF A MESOSCALE CONVECTIVE COMPLEX A Thesis by GREG LEANDER DIAL Submitted to the Office of Graduate Studies of Texas A8 M University in partial...&j Leandor Dial Approved as lo style and content by: Kcnnctt& C, ftrunrti&lgc (Ctn&i& ol' Co&nn&ittcc) (I tcn&l&c&) Norman W. Na glc (Mcmbcr) E ar . ipscr (I les&I of Dcpartmcnt) I 1 a y I 9 &3 0 ABSTRACT A Case Study of the Mesoscale and Synoptic...

  16. Use of ARM observations and numerical models to determine radiative and latent heating profiles of mesoscale convective systems for general circulation models

    SciTech Connect (OSTI)

    Houze, Jr., Robert A.

    2013-11-13

    We examined cloud radar data in monsoon climates, using cloud radars at Darwin in the Australian monsoon, on a ship in the Bay of Bengal in the South Asian monsoon, and at Niamey in the West African monsoon. We followed on with a more in-depth study of the continental MCSs over West Africa. We investigated whether the West African anvil clouds connected with squall line MCSs passing over the Niamey ARM site could be simulated in a numerical model by comparing the observed anvil clouds to anvil structures generated by the Weather Research and Forecasting (WRF) mesoscale model at high resolution using six different ice-phase microphysical schemes. We carried out further simulations with a cloud-resolving model forced by sounding network budgets over the Niamey region and over the northern Australian region. We have devoted some of the effort of this project to examining how well satellite data can determine the global breadth of the anvil cloud measurements obtained at the ARM ground sites. We next considered whether satellite data could be objectively analyzed to so that their large global measurement sets can be systematically related to the ARM measurements. Further differences were detailed between the land and ocean MCS anvil clouds by examining the interior structure of the anvils with the satellite-detected the CloudSat Cloud Profiling Radar (CPR). The satellite survey of anvil clouds in the Indo-Pacific region was continued to determine the role of MCSs in producing the cloud pattern associated with the MJO.

  17. A system of launchable mesoscale robots for distributed sensing

    E-Print Network [OSTI]

    Voyles, Richard

    A system of launchable mesoscale robots for distributed sensing Kemal B. Yesina , Bradley J technologies to develop active vision modules for the mesoscale robot. A single chip CMOS video sensor is used- log video signals from the camera. Keywords: launchable, mobile, mesoscale, camera, pan-tilt 1

  18. Impact of Resolution on Simulation of Closed Mesoscale Cellular Convection Identified by Dynamically Guided Watershed Segmentation

    SciTech Connect (OSTI)

    Martini, Matus; Gustafson, William I.; Yang, Qing; Xiao, Heng

    2014-11-27

    Organized mesoscale cellular convection (MCC) is a common feature of marine stratocumulus that forms in response to a balance between mesoscale dynamics and smaller scale processes such as cloud radiative cooling and microphysics. We use the Weather Research and Forecasting model with chemistry (WRF-Chem) and fully coupled cloud-aerosol interactions to simulate marine low clouds during the VOCALS-REx campaign over the southeast Pacific. A suite of experiments with 3- and 9-km grid spacing indicates resolution-dependent behavior. The simulations with finer grid spacing have smaller liquid water paths and cloud fractions, while cloud tops are higher. The observed diurnal cycle is reasonably well simulated. To isolate organized MCC characteristics we develop a new automated method, which uses a variation of the watershed segmentation technique that combines the detection of cloud boundaries with a test for coincident vertical velocity characteristics. This ensures that the detected cloud fields are dynamically consistent for closed MCC, the most common MCC type over the VOCALS-REx region. We demonstrate that the 3-km simulation is able to reproduce the scaling between horizontal cell size and boundary layer height seen in satellite observations. However, the 9-km simulation is unable to resolve smaller circulations corresponding to shallower boundary layers, instead producing invariant MCC horizontal scale for all simulated boundary layers depths. The results imply that climate models with grid spacing of roughly 3 km or smaller may be needed to properly simulate the MCC structure in the marine stratocumulus regions.

  19. Technical Sessions Parameterization of Convective Clouds, Mesoscale Convective Systems,

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S. Coal StocksSuppliersmillion Technical SessionsM.P. Daum

  20. Q. J. R. Meteorol. Soc. (2006), 132, pp. 709736 doi: 10.1256/qj.04.141 Momentum transport processes in the stratiform regions of mesoscale

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    2006-01-01

    processes in the stratiform regions of mesoscale convective systems over the western Pacific warm pool By DAVID B. MECHEM1, SHUYI S. CHEN2 and ROBERT A. HOUZE, Jr.3 1Cooperative Institute for Mesoscale of mesoscale convective systems (MCSs) during the Tropical Ocean­Global Atmosphere Coupled Ocean

  1. Mesoscale modeling of electrical percolation in fiber-filled systems Sameer S. Rahatekar and Marc Hamm

    E-Print Network [OSTI]

    Elliott, James

    Mesoscale modeling of electrical percolation in fiber-filled systems Sameer S. Rahatekar and Marc online 4 October 2005 The research described in this paper primarily involves mesoscale simulations

  2. Intercomparison of mesoscale meteorological models for precipitation forecasting Hydrology and Earth System Sciences, 7(6), 799811 (2003) EGU

    E-Print Network [OSTI]

    Boyer, Edmond

    2003-01-01

    Intercomparison of mesoscale meteorological models for precipitation forecasting 799 Hydrology and Earth System Sciences, 7(6), 799811 (2003) © EGU Intercomparison of mesoscale meteorological models

  3. Mesoscale Simulation of Tropical Cyclones in the South Pacific: Climatology and Interannual Variability

    E-Print Network [OSTI]

    Mesoscale Simulation of Tropical Cyclones in the South Pacific: Climatology and Interannual is shown to reproduce a wide range of mesoscale convective systems. Tropical cyclones grow from the most related to mesoscale in- teractions, which also affect TC tracks and the resulting occurrence. 1

  4. Real-Time Forecasting for the Antarctic: An Evaluation of the Antarctic Mesoscale Prediction System (AMPS)*

    E-Print Network [OSTI]

    Howat, Ian M.

    Real-Time Forecasting for the Antarctic: An Evaluation of the Antarctic Mesoscale Prediction System. MANNING AND JORDAN G. POWERS Mesoscale and Microscale Meteorology Division, National Center.S. Antarctic Program's field operations, the Antarctic Mesoscale Prediction System (AMPS) was implemented in Oc

  5. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    Isolating Mesoscale Coupled Ocean-Atmosphere in the KuroshioSST coupler . . . . Chapter 3 Mesoscale Ocean-Atmosphere4.2 Impact of Mesoscale SST on Precipitation Chapter 4 vi

  6. Development of the Flux-Adjusting Surface Data Assimilation System for Mesoscale Models

    E-Print Network [OSTI]

    Niyogi, Dev

    Development of the Flux-Adjusting Surface Data Assimilation System for Mesoscale Models KIRAN and temperature and for surface air temperature and water vapor mixing ratio for mesoscale models. In the FASDAS-field variables. The FASDAS is coupled to a land surface submodel in a three-dimensional mesoscale model and tests

  7. Precipitation hydrometeor type relative to the mesoscale airflow in mature

    E-Print Network [OSTI]

    Houze Jr., Robert A.

    Precipitation hydrometeor type relative to the mesoscale airflow in mature oceanic deep convection systems whose contiguous precipitation spans at least ~100 km in one direction [Houze 2004]. These cloud systems are composed of small, intensely precipitating convective regions and expansive stratiform regions

  8. Posters Mesoscale Simulations of Convective Systems with Data Assimilation During

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgram Guidelines This document outlines the majorL.Posters9

  9. Sensitivity of mesoscale gravity waves to the baroclinicity of jet-front systems 

    E-Print Network [OSTI]

    Wang, Shuguang

    2006-04-12

    To investigate the generation of mesoscale gravity waves from upper-tropospheric jet-front systems, five different life cycles of baroclinic waves are simulated with a high-resolution mesoscale model (MM5 with 10-km grid spacing). The baroclinicity...

  10. Sensitivity of Mesoscale Gravity Waves to the Baroclinicity of Jet-Front Systems SHUGUANG WANG AND FUQING ZHANG

    E-Print Network [OSTI]

    Sensitivity of Mesoscale Gravity Waves to the Baroclinicity of Jet-Front Systems SHUGUANG WANG of mesoscale gravity waves to the baroclinicity of the background jet-front systems by simulating different life cycles of baroclinic waves with a high-resolution mesoscale model. Four simulations are made

  11. THE PRECIPITATION REGIME OF DRONNING MAUD LAND, ANTARCTICA, DERIVED FROM AMPS (ANTARCTIC MESOSCALE PREDICTION SYSTEM) ARCHIVE DATA

    E-Print Network [OSTI]

    Schlosser, Elisabeth

    THE PRECIPITATION REGIME OF DRONNING MAUD LAND, ANTARCTICA, DERIVED FROM AMPS (ANTARCTIC MESOSCALE. Manning2) 1) Institute of Meteorology and Geophysics, University of Innsbruck, Austria 2) Mesoscale the temporal and spatial distribution of precipitation in DML using AMPS (Antarctic Mesoscale Prediction System

  12. The Regional Atmospheric Modeling System (RAMS): Development for Parallel Processing Computer

    E-Print Network [OSTI]

    Cirne, Walfredo

    on the mesoscale (horizontal scales from 2 km to 2000 km) for purposes ranging from operational weather forecasting and simulating convective clouds, mesoscale convective systems, cirrus clouds, and precipitating weather systems models that had a great deal of overlap, the CSU cloud/mesoscale mode (Tripoli and Cotton, 1982

  13. Geothermal reservoirs in hydrothermal convection systems

    SciTech Connect (OSTI)

    Sorey, M.L.

    1982-01-01

    Geothermal reservoirs commonly exist in hydrothermal convection systems involving fluid circulation downward in areas of recharge and upwards in areas of discharge. Because such reservoirs are not isolated from their surroundings, the nature of thermal and hydrologic connections with the rest of the system may have significant effects on the natural state of the reservoir and on its response to development. Conditions observed at numerous developed and undeveloped geothermal fields are discussed with respect to a basic model of the discharge portion of an active hydrothermal convection system. Effects of reservoir development on surficial discharge of thermal fluid are also delineated.

  14. Low enthalpy convective system in Western Ohio

    SciTech Connect (OSTI)

    Cannon, M.S.; Tabet, C.A.; Eckstein, Y.

    1980-01-01

    A distinct positive anomaly in the temperatures of the shallow (Pleistocene) aquifers along the Cincinnati-Findlay Arch in Western Ohio coincides with a low geothermal gradient. A conceptual model of convective currents associated with a tensional fault and/or fracture system along the crest of the Arch is suggested as an explanation of the anomaly. Hydrochemical information indicates that various quantities of warmer ground water, with the composition characteristics of deep bedrock aquifers, is present as an admixture in the shallow aquifers. This confirms the conceptual model of convection in fractures.

  15. Synoptic and mesoscale controls on the isotopic composition of individual storms systems striking the western US

    E-Print Network [OSTI]

    Johnson, KR; Berkelhammer, M; Stott, L; Kei, Y

    2012-01-01

    011-1262-3 Synoptic and mesoscale controls on the isotopicet al. : Synoptic and mesoscale controls on the isotopicrecord of syn- optic and mesoscale atmospheric processes. In

  16. Convective heat transport in geothermal systems

    SciTech Connect (OSTI)

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

    1986-08-01

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

  17. Spatially Modulated Structures in Convective Systems

    E-Print Network [OSTI]

    Kao, Hsien-Ching

    2013-01-01

    Mode in Pattern Formation Convection in a horizontal ?uid layer rotating about the vertical or subject

  18. Precipitation characteristics of CAM5 physics at mesoscale resolution during MC3E and the impact of convective timescale choice

    SciTech Connect (OSTI)

    Gustafson, William I.; Ma, Po-Lun; Singh, Balwinder

    2014-12-01

    The physics suite of the Community Atmosphere Model version 5 (CAM5) has recently been implemented in the Weather Research and Forecasting (WRF) model to explore the behavior of the parameterization suite at high resolution and in the more controlled setting of a limited area model. The initial paper documenting this capability characterized the behavior for northern high latitude conditions. This present paper characterizes the precipitation characteristics for continental, mid-latitude, springtime conditions during the Midlatitude Continental Convective Clouds Experiment (MC3E) over the central United States. This period exhibited a range of convective conditions from those driven strongly by large-scale synoptic regimes to more locally driven convection. The study focuses on the precipitation behavior at 32 km grid spacing to better anticipate how the physics will behave in the global model when used at similar grid spacing in the coming years. Importantly, one change to the Zhang-McFarlane deep convective parameterization when implemented in WRF was to make the convective timescale parameter an explicit function of grid spacing. This study examines the sensitivity of the precipitation to the default value of the convective timescale in WRF, which is 600 seconds for 32 km grid spacing, to the value of 3600 seconds used for 2 degree grid spacing in CAM5. For comparison, an infinite convective timescale is also used. The results show that the 600 second timescale gives the most accurate precipitation over the central United States in terms of rain amount. However, this setting has the worst precipitation diurnal cycle, with the convection too tightly linked to the daytime surface heating. Longer timescales greatly improve the diurnal cycle but result in less precipitation and produce a low bias. An analysis of rain rates shows the accurate precipitation amount with the shorter timescale is assembled from an over abundance of drizzle combined with too little heavy rain events. With longer timescales one can improve the distribution, particularly for the extreme rain rates. Ultimately, without changing other aspects of the physics, one must choose between accurate diurnal timing and rain amount when choosing an appropriate convective timescale.

  19. Precipitation characteristics of CAM5 physics at mesoscale resolution during MC3E and the impact of convective timescale choice

    SciTech Connect (OSTI)

    Gustafson, William I.; Ma, Po-Lun; Singh, Balwinder

    2014-12-17

    The physics suite of the Community Atmosphere Model version 5 (CAM5) has recently been implemented in the Weather Research and Forecasting (WRF) model to explore the behavior of the parameterization suite at high resolution and in the more controlled setting of a limited area model. The initial paper documenting this capability characterized the behavior for northern high latitude conditions. This present paper characterizes the precipitation characteristics for continental, mid-latitude, springtime conditions during the Midlatitude Continental Convective Clouds Experiment (MC3E) over the central United States. This period exhibited a range of convective conditions from those driven strongly by large-scale synoptic regimes to more locally driven convection. The study focuses on the precipitation behavior at 32 km grid spacing to better anticipate how the physics will behave in the global model when used at similar grid spacing in the coming years. Importantly, one change to the Zhang-McFarlane deep convective parameterization when implemented in WRF was to make the convective timescale parameter an explicit function of grid spacing. This study examines the sensitivity of the precipitation to the default value of the convective timescale in WRF, which is 600 seconds for 32 km grid spacing, to the value of 3600 seconds used for 2 degree grid spacing in CAM5. For comparison, an infinite convective timescale is also used. The results show that the 600 second timescale gives the most accurate precipitation over the central United States in terms of rain amount. However, this setting has the worst precipitation diurnal cycle, with the convection too tightly linked to the daytime surface heating. Longer timescales greatly improve the diurnal cycle but result in less precipitation and produce a low bias. An analysis of rain rates shows the accurate precipitation amount with the shorter timescale is assembled from an over abundance of drizzle combined with too little heavy rain events. With longer timescales one can improve the distribution, particularly for the extreme rain rates. Ultimately, without changing other aspects of the physics, one must choose between accurate diurnal timing and rain amount when choosing an appropriate convective timescale.

  20. Precipitation characteristics of CAM5 physics at mesoscale resolution during MC3E and the impact of convective timescale choice

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gustafson, William I.; Ma, Po-Lun; Singh, Balwinder

    2014-12-17

    The physics suite of the Community Atmosphere Model version 5 (CAM5) has recently been implemented in the Weather Research and Forecasting (WRF) model to explore the behavior of the parameterization suite at high resolution and in the more controlled setting of a limited area model. The initial paper documenting this capability characterized the behavior for northern high latitude conditions. This present paper characterizes the precipitation characteristics for continental, mid-latitude, springtime conditions during the Midlatitude Continental Convective Clouds Experiment (MC3E) over the central United States. This period exhibited a range of convective conditions from those driven strongly by large-scale synoptic regimesmore »to more locally driven convection. The study focuses on the precipitation behavior at 32 km grid spacing to better anticipate how the physics will behave in the global model when used at similar grid spacing in the coming years. Importantly, one change to the Zhang-McFarlane deep convective parameterization when implemented in WRF was to make the convective timescale parameter an explicit function of grid spacing. This study examines the sensitivity of the precipitation to the default value of the convective timescale in WRF, which is 600 seconds for 32 km grid spacing, to the value of 3600 seconds used for 2 degree grid spacing in CAM5. For comparison, an infinite convective timescale is also used. The results show that the 600 second timescale gives the most accurate precipitation over the central United States in terms of rain amount. However, this setting has the worst precipitation diurnal cycle, with the convection too tightly linked to the daytime surface heating. Longer timescales greatly improve the diurnal cycle but result in less precipitation and produce a low bias. An analysis of rain rates shows the accurate precipitation amount with the shorter timescale is assembled from an over abundance of drizzle combined with too little heavy rain events. With longer timescales one can improve the distribution, particularly for the extreme rain rates. Ultimately, without changing other aspects of the physics, one must choose between accurate diurnal timing and rain amount when choosing an appropriate convective timescale.« less

  1. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    productive oceanic eastern boundary current, providing anCurrent System and the Kuroshio Extension uses OFES products for their oceanic

  2. Convection?

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit the followingConcentratingPortal ControllingConvection feedbacks in a What

  3. Engineering mesoscale structures with distinct dynamical implications

    E-Print Network [OSTI]

    Engineering mesoscale structures with distinct dynamical implications Anne-Ly Do1 , Johannes H that there are certain mesoscale subgraphs that have precise and distinct consequences for the system-level dynamics. In particular, if mesoscale symmetries are present then eigenvectors of the Jacobian localise on the symmetric

  4. Passive microwave observations of mesoscale convective systems over the tropical Pacific Ocean 

    E-Print Network [OSTI]

    McGaughey, Gary Rae

    1994-01-01

    the Advanced Microwave Precipitation Radiometer (AMPR) aboard the NASA ER2 during the Tropical Ocean and Global Atmosphere Coupled-Ocean Atmosphere Response Experiment (TOGA-COARE). The AMPR measures linearly polarized radiation at 10.7, 19.35, 37. 1, and 85...

  5. Application of the 85 GHz ice scattering signature to a global study of mesoscale convective systems 

    E-Print Network [OSTI]

    Devlin, Karen Irene

    1995-01-01

    had the largest number of very large (> 1 0 5 @) MCSS. Over the oceans, median brightness temperature depression was 20-30 K below 225 K, while over land, it was 35-45 K below 225 K. Tropical Africa had the coldest median minimum brightness temperature...

  6. Organization and Environmental Properties of Extreme-Rain-Producing Mesoscale Convective Systems

    E-Print Network [OSTI]

    Schumacher, Russ

    -kilometer national composite radar reflectivity data are then used to examine the structure and evolution of each. Doswell et al. (1996, hereafter DBM96) note that the total precipitation at any point is directly pro

  7. A comparison of tropical mesoscale convective systems in El Nino and La Nina 

    E-Print Network [OSTI]

    Zolman, Jody Lynn

    1999-01-01

    ). The number, size, and intensity of the MCSs were examined for differences between the years in eighteen different regions. There are well documented patterns of anomalous precipitation due to El Nino and La Nina, and in general the MCS distributions between...

  8. Equilibrium Structure of a Triblock Copolymer System Revealed by Mesoscale Simulation and Neutron Scattering

    SciTech Connect (OSTI)

    Do, Changwoo [ORNL] [ORNL; Chen, Wei-Ren [ORNL] [ORNL; Hong, Kunlun [ORNL] [ORNL; Smith, Gregory Scott [ORNL] [ORNL

    2013-01-01

    We have performed both mesoscale simulations and neutron scattering experiments on Pluronic L62, a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymer system in aqueous solution. The influence of simulation variables such PEO/PPO block ratio, interaction parameters, and coarse-graining methods is extensively investigated by covering all permutations of parameters found in the literatures. Upon increasing the polymer weight fraction from 50 wt% to 90 wt%, the equilibrium structure of the isotropic, reverse micellar, bicontinuous, worm-like micelle network, and lamellar phases are respectively predicted from the simulation depending on the choices of simulation parameters. Small angle neutron scattering (SANS) measurements show that the same polymer systems exhibit the spherical micellar, lamellar, and reverse micellar phases with the increase of the copolymer concentration at room temperature. Detailed structural analysis and comparison with simulations suggest that one of the simulation parameter sets can provide reasonable agreement with the experimentally observed structures.

  9. Numerical Simulation of Mesoscale Circulations in a Region of Contrasting Soil Types

    E-Print Network [OSTI]

    Raman, Sethu

    Numerical Simulation of Mesoscale Circulations in a Region of Contrasting Soil Types SETHU RAMAN,1 AARON SIMS,1,2 ROBB ELLIS,1 and RYAN BOYLES 1 Abstract--Mesoscale processes that form due to changes on mesoscale processes are examined. Climatological analyses indicate increased convective precipitation

  10. Larval fish assemblages and mesoscale oceanographic structure along the Mesoamerican Barrier Reef System

    E-Print Network [OSTI]

    Larval fish assemblages and mesoscale oceanographic structure along the Mesoamerican Barrier Reef Caribbean region, and contains spawning sites for a number of reef fish species. Despite this, little is known of the distribution and transport of pelagic fish larvae in the area, and basic in situ

  11. Mesoscale hybrid calibration artifact

    SciTech Connect (OSTI)

    Tran, Hy D. (Albuquerque, NM); Claudet, Andre A. (Albuquerque, NM); Oliver, Andrew D. (Waltham, MA)

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  12. Constructing Irregular Surfaces to Enclose Macromolecular Complexes for Mesoscale Modeling Using the Discrete

    E-Print Network [OSTI]

    Schlick, Tamar

    Constructing Irregular Surfaces to Enclose Macromolecular Complexes for Mesoscale Modeling Using proteins. DiSCO is generally applicable to other interesting macromolecular systems for which mesoscale

  13. Adaptive Thermal Management for Portable System Batteries by Forced Convection Cooling

    E-Print Network [OSTI]

    Pedram, Massoud

    Adaptive Thermal Management for Portable System Batteries by Forced Convection Cooling Qing Xie a portable system. Since the cooling fan is also powered by the same battery, it is critical to develop thermal management problem for batteries (ATMB) in the portable systems with forced convection cooling

  14. The role of land surface processes on the mesoscale simulation of the July 26, 2005 heavy rain event over Mumbai, India

    E-Print Network [OSTI]

    Niyogi, Dev

    The role of land surface processes on the mesoscale simulation of the July 26, 2005 heavy rain Mesoscale convection Weather research and forecast model Indian summer monsoon Land surface processes

  15. The impact of agricultural intensification and irrigation on landatmosphere interactions and Indian monsoon precipitation --A mesoscale modeling perspective

    E-Print Network [OSTI]

    Douglas, Ellen M.

    and Indian monsoon precipitation -- A mesoscale modeling perspective E.M. Douglas a, , A. Beltrán-Przekurat b and regional convergence, mesoscale convection, and precipitation patterns over the Indian monsoon region. Four circulation pattern and changes in mesoscale precipitation. These agricultural changes, including irrigation

  16. The impact of agricultural intensification and irrigation on landatmosphere interactions and Indian monsoon precipitation --A mesoscale modeling perspective

    E-Print Network [OSTI]

    Niyogi, Dev

    and Indian monsoon precipitation -- A mesoscale modeling perspective E.M. Douglas a, , A. Beltrán-Przekurat b convergence, mesoscale convection, and precipitation patterns over the Indian monsoon region. Four experiments pattern and changes in mesoscale precipitation. These agricultural changes, including irrigation modify

  17. Acoustic Characterization of Mesoscale Objects

    SciTech Connect (OSTI)

    Chinn, D; Huber, R; Chambers, D; Cole, G; Balogun, O; Spicer, J; Murray, T

    2007-03-13

    This report describes the science and engineering performed to provide state-of-the-art acoustic capabilities for nondestructively characterizing mesoscale (millimeter-sized) objects--allowing micrometer resolution over the objects entire volume. Materials and structures used in mesoscale objects necessitate the use of (1) GHz acoustic frequencies and (2) non-contacting laser generation and detection of acoustic waves. This effort demonstrated that acoustic methods at gigahertz frequencies have the necessary penetration depth and spatial resolution to effectively detect density discontinuities, gaps, and delaminations. A prototype laser-based ultrasonic system was designed and built. The system uses a micro-chip laser for excitation of broadband ultrasonic waves with frequency components reaching 1.0 GHz, and a path-stabilized Michelson interferometer for detection. The proof-of-concept for mesoscale characterization is demonstrated by imaging a micro-fabricated etched pattern in a 70 {micro}m thick silicon wafer.

  18. Experimental Investigation of Natural Convection in Trombe Wall Systems 

    E-Print Network [OSTI]

    Chen, B.; Zhao, J.; Chen, C.; Zhuang, Z.

    2006-01-01

    In this paper, experiments with a passive solar building with Trombe wall in the north cold climate are carried out and discussed, and the natural convection heat transfer process has been investigated. The relativity of the factors affecting indoor...

  19. Convection venting lensed reflector-type compact fluorescent lamp system

    DOE Patents [OSTI]

    Pelton, B.A.; Siminovitch, M.

    1997-07-29

    Disclosed herein is a fluorescent lamp housing assembly capable of providing convection cooling to the lamp and the ballast. The lens of the present invention includes two distinct portions, a central portion and an apertured portion. The housing assembly further includes apertures so that air mass is able to freely move up through the assembly and out ventilation apertures. 12 figs.

  20. Search for: mesoscale | DOE PAGES

    Office of Scientific and Technical Information (OSTI)

    mesoscale Find + Advanced Search Advanced Search All Fields: mesoscale Title: Full Text: Bibliographic Data: Creator Author: Name Name ORCID Search Authors Type: All Accepted...

  1. SciTech Connect: mesoscale

    Office of Scientific and Technical Information (OSTI)

    mesoscale Find + Advanced Search Term Search Semantic Search Advanced Search All Fields: mesoscale Semantic Semantic Term Title: Full Text: Bibliographic Data: Creator Author:...

  2. The evolution of total lightning and radar reflectivity characteristics of two mesoscale convective systems over Houston, Texas 

    E-Print Network [OSTI]

    Hodapp, Charles Lee

    2009-05-15

    production of MCSs. The stratiform areas quadruple in size and the mean reflectivity values increase substantially by ~ 6 dB. As the stratiform region matures, VHF source density plots show a lightning pathway that slopes rearward and downward from the back...

  3. A Statistical Analysis of Characteristics of Mesoscale Convective System Mountain Initiation Location Clusters in the Arkansas-Red River Basin

    E-Print Network [OSTI]

    Callen, Elisabeth F.

    2012-12-31

    American Regional Reanalysis (NARR) data was gathered NOMADS (National Climatic Data Center 2011). Once observations for all the variables were gathered for each MCS cluster, Multiple Linear Regressions (MLRs) and Principal Component Analyses (PCAs) were...

  4. Mesoscale Modeling Spring Semester 2014

    E-Print Network [OSTI]

    van den Heever, Susan C.

    ATS730 Mesoscale Modeling Spring Semester 2014 Meeting Times: T/TH: 9-10:15am Room: ATS 101 is to present the development of the basic equations used in mesoscale models, as well as the various methods than on actual simulations of mesoscale phenomena or the evaluation of specific mesoscale models

  5. Convective plasma stability consistent with MHD equilibrium in magnetic confinement systems with a decreasing field

    SciTech Connect (OSTI)

    Tsventoukh, M. M. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2010-10-15

    A study is made of the convective (interchange, or flute) plasma stability consistent with equilibrium in magnetic confinement systems with a magnetic field decreasing outward and large curvature of magnetic field lines. Algorithms are developed which calculate convective plasma stability from the Kruskal-Oberman kinetic criterion and in which the convective stability is iteratively consistent with MHD equilibrium for a given pressure and a given type of anisotropy in actual magnetic geometry. Vacuum and equilibrium convectively stable configurations in systems with a decreasing, highly curved magnetic field are calculated. It is shown that, in convectively stable equilibrium, the possibility of achieving high plasma pressures in the central region is restricted either by the expansion of the separatrix (when there are large regions of a weak magnetic field) or by the filamentation of the gradient plasma current (when there are small regions of a weak magnetic field, in which case the pressure drops mainly near the separatrix). It is found that, from the standpoint of equilibrium and of the onset of nonpotential ballooning modes, a kinetic description of convective stability yields better plasma confinement parameters in systems with a decreasing, highly curved magnetic field than a simpler MHD model and makes it possible to substantially improve the confinement parameters for a given type of anisotropy. For the Magnetor experimental compact device, the maximum central pressure consistent with equilibrium and stability is calculated to be as high as {beta} {approx} 30%. It is shown that, for the anisotropy of the distribution function that is typical of a background ECR plasma, the limiting pressure gradient is about two times steeper than that for an isotropic plasma. From a practical point of view, the possibility is demonstrated of achieving better confinement parameters of a hot collisionless plasma in systems with a decreasing, highly curved magnetic field than those obtained with the simplest MHD description.

  6. Mesoscale Self-Assembly of Hexagonal Plates Using Lateral Capillary Forces: Synthesis Using the "Capillary Bond"

    E-Print Network [OSTI]

    Prentiss, Mara

    Mesoscale Self-Assembly of Hexagonal Plates Using Lateral Capillary Forces: Synthesis Using examines self-assembly in a quasi-two-dimensional, mesoscale system. The system studied here involves-assembly from the molecular to the mesoscale, (ii) the demonstration of a system in which small objects can

  7. Journal of the Mechanics and Physics of Solids 56 (2008) 14501459 Shocks and slip systems: Predictions from a mesoscale theory of

    E-Print Network [OSTI]

    Sethna, James P.

    2008-01-01

    : Predictions from a mesoscale theory of continuum dislocation dynamics S. Limkumnerda,Ã, J.P. Sethnab a Zernike developed mesoscale continuum theory of dislocation dynamics, we derive three predictions about plasticity

  8. A numerical simulation of slantwise convection: its structure and evolution 

    E-Print Network [OSTI]

    Overpeck, Scott Allen

    2001-01-01

    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...

  9. Copyright (to be inserted by the publisher ) Mesoscale simulation of grain growth

    E-Print Network [OSTI]

    Citation & Copyright (to be inserted by the publisher ) Mesoscale simulation of grain growth David, USA Keywords: grain growth, mesoscale, algorithm, dissipative system, Mullins Equation, Herring. Here we exhibit a consistent variational approach to the mesoscale simulation of large systems of grain

  10. Asymmetric Catalysis at the Mesoscale: Gold Nanoclusters Embedded in Chiral Self-Assembled Monolayer as Heterogeneous

    E-Print Network [OSTI]

    Asymmetric Catalysis at the Mesoscale: Gold Nanoclusters Embedded in Chiral Self of the catalytically active metallic sites and the surrounding chiral SAM for the formation of a mesoscale the catalytically active site from the nanoscale to the mesoscale, which implies a principle of operating systems

  11. Modeling the Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature

    E-Print Network [OSTI]

    Kurapov, Alexander

    Modeling the Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current region-Atmosphere Mesoscale Prediction System (COAMPS) atmospheric models. The SST-induced wind response is assessed from

  12. Modeling the Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature Perturbations

    E-Print Network [OSTI]

    Kurapov, Alexander

    Modeling the Atmospheric Boundary Layer Wind Response to Mesoscale Sea Surface Temperature received 25 October 2013, in final form 24 July 2014) ABSTRACT The wind speed response to mesoscale SST Research and Forecasting (WRF) Model and the U.S. Navy Coupled Ocean­Atmosphere Mesoscale Prediction System

  13. MESOSCALE DESCRIPTION OF DEFECTED MATERIALS

    E-Print Network [OSTI]

    Vinals, Jorge

    MESOSCALE DESCRIPTION OF DEFECTED MATERIALS Jorge Vi~nals School of Physics and Astronomy. Laughlin) Small but finite wavenumber and finite frequency ("mesoscale") response functions and transport;MESOSCALE DESCRIPTION B B B B B B B A B A B A A B B A A A A BB A B Microscopic Mesoscopic Macroscopic vn

  14. Mesoscale Dynamics Spring Semester 2014

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    ATS 735 Mesoscale Dynamics (3 cr) Spring Semester 2014 Instructor: Richard H. Johnson, Room ATS 305: There are no required texts. The recent book Mesoscale Meteorology in Midlatitudes by Markowski and Richardson covers with mesoscale-related research. A set of notes will be made available for the course, although we will not cover

  15. Mesoscale Dynamics Spring Semester 2012

    E-Print Network [OSTI]

    Birner, Thomas

    ATS 735 Mesoscale Dynamics (3 cr) Spring Semester 2012 Instructor: Richard H. Johnson, Room ATS 305: There are no required texts. The recent book Mesoscale Meteorology in Midlatitudes by Markowski and Richardson covers with mesoscale-related research. A set of notes will be made available for the course, although we will not cover

  16. 4, 54555514, 2004 Mesoscale modeling

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ACPD 4, 5455­5514, 2004 Mesoscale modeling of combined aerosol and photo-oxidant processes M Union 2004 Atmospheric Chemistry and Physics Discussions Mesoscale modeling of combined aerosol­5514, 2004 Mesoscale modeling of combined aerosol and photo-oxidant processes M. Lazaridis et al. Title Page

  17. 7, 1043910465, 2007 Mesoscale inversion

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 7, 10439­10465, 2007 Mesoscale inversion T. Lauvaux et al. Title Page Abstract Introduction Discussions Mesoscale inversion: first results from the CERES campaign with synthetic data T. Lauvaux 1,2 , M.lauvaux@lsce.ipsl.fr) 10439 #12;ACPD 7, 10439­10465, 2007 Mesoscale inversion T. Lauvaux et al. Title Page Abstract

  18. Seabird associations with mesoscale eddies: the subtropical Indian Ocean

    E-Print Network [OSTI]

    Hyrenbach, KD; Veit, RR; Weimerskirch, H; Jr, HGL

    2006-01-01

    Seabird associations with mesoscale eddies: the subtropicalsur- hydrographic fronts and mesoscale eddies (Haney & veyedclimatologies. J Clim mesoscale variability across ocean

  19. Natural convection heat transport in a small, HLMC reactor system

    SciTech Connect (OSTI)

    Spencer, B.W.; Sienicki, J.J.; Farmer, M.T.

    1999-09-01

    Concepts are being developed and evaluated at Argonne National Laboratory for a small nuclear steam supply system (NSSS) with proliferation-resistant features targeted for export to developing countries. Here the authors are specifically investigating how simple and compact such a system can be. A heavy-liquid-metal coolant (HLMC) is being considered owing to its excellent heat transport characteristics and its relative inertness with the reference thermodynamic working fluid (water/steam). The purpose of the present work is to explore the possibility to take advantage of these HLMC characteristics by eliminating the intermediate loop needed in sodium-cooled systems and additionally eliminating the primary system coolant pumps. The criteria imposed on the system include the following: (1) low power, i.e., 300 MW(thermal); (2) small size for factory fabrication and overland transportation; (3) elimination of fuel access at the site (no refueling, fuel shuffling, nor storage at site); integral fueled module replacement at 15-yr goal interval; and (4) completion of all research and development needed for detailed prototype design within 5 yr. To accomplish the latter requirement, the authors are addressing whether existing coolant and materials technology is capable of supporting the sought-after simplifications. In this regard, they are at present considering technology developed in Russia for Pb-Bi eutectic as a reactor coolant and ferritic-martensitic stainless steel with oxide-layer corrosion protection as cladding. The figure of merit in the investigation is the peak cladding temperature insofar as the cladding technology is considered proven to {approximately}600 C.

  20. Convectively stable pressure profile in magnetic confinement systems with internal rings

    SciTech Connect (OSTI)

    Tsventoukh, M. M. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2010-06-15

    A convectively stable pressure profile in a long multiple-mirror (corrugated) magnetic confinement system with internal current-carrying rings is calculated. The plasma energy content in the axial region can be increased by using an internal ring that reverses the on-axis magnetic field direction and gives rise to an average magnetic well near the axis. The pressure profile in the outer region-outside the magnetic well-is considered in detail. It is shown that, in the radial pressure profile, a pedestal can be formed that leads to a higher pressure drop between the center and the plasma edge. The pressure profile is calculated from the Kruskal-Oberman criterion-a necessary and sufficient condition for the convective stability of a collisionless plasma. The revealed pedestal arises near the boundary of the average magnetic well in the region of the smallest but alternating-sign curvature of the magnetic field lines due to a break in the convectively stable pressure profile. Such a shape of the stable pressure profile can be attributed to the stabilizing effect of the alternating-sign curvature of the field lines in the multiple-mirror magnetic confinement systems under consideration.

  1. Evolutionary games defined at the network mesoscale: The Public Jesus Gomez-Garden~es,1,2,3,a)

    E-Print Network [OSTI]

    Sánchez, Angel "Anxo"

    Evolutionary games defined at the network mesoscale: The Public Goods game Jesu´s Go on the mesoscale level of large social systems, that promotes cooperation. Moreover, we fur- ther show

  2. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    2000: A Coupled Air-Sea Mesoscale Model: Experiments inWind Stress Curl from a Mesoscale Model. Mon. Wea. Rev. ,2006: Effect of Ocean Mesoscale Variability on the Mean

  3. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    2000: A Coupled Air-Sea Mesoscale Model: Experiments inWind Stress Curl from a Mesoscale Model. Mon. Wea. Rev. ,2006: Effect of Ocean Mesoscale Variability on the Mean

  4. Mesoscale coupled ocean-atmosphere interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    mesoscale oceanic features are current coarse resolutionmesoscale r current variability associated with oceanic ringthe TIW- currents. These mesoscale oceanic and atmospheric

  5. Mesoscale Coupled Ocean-Atmosphere Interaction

    E-Print Network [OSTI]

    Seo, Hyodae

    2007-01-01

    mesoscale oceanic features are current coarse resolutionmesoscale r current variability associated with oceanic ringthe TIW- currents. These mesoscale oceanic and atmospheric

  6. Mesoscale Simulations of Coarsening in GB Networks

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

    Mukul Kumar is the Principal Investigator for Mesoscale Simulations of Coarsening in GB Networks LLNL BES Programs Highlight Mesoscale Simulations of Coarsening in GB Networks The...

  7. 1 van der Waals Interactions on the Mesoscale: Open-Science 2 Implementation, Anisotropy, Retardation, and Solvent Effects

    E-Print Network [OSTI]

    Podgornik, Rudolf

    1 van der Waals Interactions on the Mesoscale: Open-Science 2 Implementation, Anisotropy Ljubljana, Slovenia 13 ABSTRACT: The self-assembly of heterogeneous mesoscale systems is mediated by 14 long-range interactions, including van der Waals forces. Diverse mesoscale 15 architectures, built of optically

  8. Copyright (to be inserted by the publisher ) Mesoscale Simulation of the Evolution of the Grain Boundary Character

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    Citation & Copyright (to be inserted by the publisher ) Mesoscale Simulation of the Evolution; Simulation; Grain boundary energy; Mullins Equation Abstract. A mesoscale, variational simulation of grain to the mesoscale simulation of grain growth in large two dimensional systems to study the evolution of the grain

  9. LMD Martian Mesoscale Model User Manual

    E-Print Network [OSTI]

    Spiga, Aymeric

    LMD Martian Mesoscale Model [LMD-MMM] User Manual A. Spiga aymeric.spiga@upmc.fr Laboratoire de;#12;Contents 1 What is the LMD Martian Mesoscale Model? 3 1.1 Dynamical core on mesoscale levels . . . . . . . . . . . . . . . 35 iii #12;iv User Manual for the LMD Martian Mesoscale Model

  10. METR 4433, Mesoscale Meteorology Spring 2011

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    METR 4433, Mesoscale Meteorology Spring 2011 Instructor Dr. Kelvin K. Droegemeier Office: Three, 1:00 ­ 2:30 pm Required Text Markowski, P. and Y. Richardson: Mesoscale Meteorology in Midlatitudes and physical analysis techniques to mesoscale phenomena. Topics include definition of the term "mesoscale

  11. ATS 641: Mesoscale Meteorology Spring 2014

    E-Print Network [OSTI]

    ATS 641: Mesoscale Meteorology Spring 2014 TR, 1:00-2:50 PM, ATS Room 101 Course Description and Prerequisites This course will cover the theory and application of mesoscale meteorology, and how mesoscale, students will be able to: · Describe the basic theories describing mesoscale weather phenomena · Understand

  12. METR 4433, Mesoscale Meteorology Spring 2013

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    METR 4433, Mesoscale Meteorology Spring 2013 Instructor Dr. Kelvin K. Droegemeier (kkd Text Markowski, P. and Y. Richardson: Mesoscale Meteorology in Midlatitudes. Wiley-Blackwell, 430pp to mesoscale phenomena. Topics include definition of the term "mesoscale," radar principles and interpretation

  13. Sleep Dynamics and Seizure Control in a Mesoscale Cortical Model

    E-Print Network [OSTI]

    Lopour, Beth Ann

    2009-01-01

    Contributions . . . . . . . . . 2 Mesoscale Cortical Modelstates in h e from the mesoscale cortical model, here- afterand Seizure Control in a Mesoscale Cortical Model by Beth

  14. Ocean color and atmospheric dimethyl sulfide: On their mesoscale variability

    E-Print Network [OSTI]

    Matrai, Patricia A; Balch, William M; Cooper, David J; Saltzman, Eric S

    1993-01-01

    periods of' time, covering mesoscale Campbell, J. W. and W.Dimethyl Sulfide' On Their Mesoscale Variability PATRICIA A.Miami, Miami, Florida The mesoscale variability of dimethyl

  15. The role of convective geothermal systems in the generation, migration, and entrapment of oil

    SciTech Connect (OSTI)

    Hulen, J.B. [Univ. of Utah Research Institute, Salt Lake City, UT (United States)

    1995-06-01

    Modern convective geothermal systems (for example, at Yellowstone National Park) and their fossil equivalents, epithermal mineral deposits (like McLaughlin, California) have traditionally been considered poor petroleum prospects. The concentrated heat which drives these systems is commonly viewed as a negative influence: in other words, any oil initially present in or generated by these systems is quickly degraded to a useless carbonaceous residue. This is true in extreme cases, but numerous examples from the Great Basin, the northern California Coast Ranges, and elsewhere suggest that under certain circumstances, geothermal systems can efficiently generate, transport, and entrap significant quantities of producible petroleum. B.R.T. Simoneit has shown that oil can be hydrothermally generated in an {open_quotes} instant{close_quotes} of geologic time. It follows, then, that away from geothermal systems` high-temperature centers (or in wholly moderate-temperature systems), the encompassing shallow thermal anomalies can distill large volumes of oil from otherwise immature hydrocarbon source rocks. Transport of this newly-generated oil is enhanced by the buoyant upwelling of heated aqueous fluid. Porosity for oil transport and storage is created or increased by hydrothermal dissolution of rock-forming or secondary silicates and carbonates. Finally, geothermal {open_quotes}self-sealing{close_quotes} -- the deposition of secondary minerals (especially silica and clay) at the margins of a system -- can provide a very effective hydrocarbon seal. Lee Allison has noted the coincidence of igneous intrusions and oil reservoirs in Nevada. It is suggested that here and elsewhere, both igneous-related and amagmatic geothermal systems in otherwise favorable settings should be viewed as prime petroleum exploration targets.

  16. ARCHITECTURE OF THE MERCURY MESOSCALE METEOROLOGICAL DATA FUSION C. Fields, C. Cavendish, M. Coombs, T. Eskridge, R. Hartley, H. Pfeiffer, and C. Soderlund

    E-Print Network [OSTI]

    Hartley, Roger

    ARCHITECTURE OF THE MERCURY MESOSCALE METEOROLOGICAL DATA FUSION C. Fields, C. Cavendish, M. Coombs mesoscale meteorological data fusion system is being developed as an intelligent interface between the U.S. Army's Integrated Meteorological System IM[ETS) mesoscale database and tactical decision aids (TDAs

  17. Soft X-ray techniques to study mesoscale magnetism

    E-Print Network [OSTI]

    Kortright, Jeffrey B.

    2003-01-01

    X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.X-Ray Techniques to Study Mesoscale Magnetism Jeffrey B.

  18. Final Technical Report for "Radiative Heating Associated with Tropical Convective Cloud Systems: Its Importance at Meso and Global Scales"

    SciTech Connect (OSTI)

    Schumacher, Courtney

    2012-12-13

    Heating associated with tropical cloud systems drive the global circulation. The overall research objectives of this project were to i) further quantify and understand the importance of heating in tropical convective cloud systems with innovative observational techniques, and ii) use global models to determine the large-scale circulation response to variability in tropical heating profiles, including anvil and cirrus cloud radiative forcing. The innovative observational techniques used a diversity of radar systems to create a climatology of vertical velocities associated with the full tropical convective cloud spectrum along with a dissection of the of the total heating profile of tropical cloud systems into separate components (i.e., the latent, radiative, and eddy sensible heating). These properties were used to validate storm-scale and global climate models (GCMs) and were further used to force two different types of GCMs (one with and one without interactive physics). While radiative heating was shown to account for about 20% of the total heating and did not have a strong direct response on the global circulation, the indirect response was important via its impact on convection, esp. in how radiative heating impacts the tilt of heating associated with the Madden-Julian Oscillation (MJO), a phenomenon that accounts for most tropical intraseasonal variability. This work shows strong promise in determining the sensitivity of climate models and climate processes to heating variations associated with cloud systems.

  19. Mesoscale symmetries explain dynamical equivalence of food webs

    E-Print Network [OSTI]

    Aufderheide, Helge; Gross, Thilo

    2012-01-01

    A present challenge in complex systems is to identify mesoscale structures that have distinct dynamical implications. In this paper we present a detailed investigation of a previously observed dynamical equivalence of certian ecological food webs. We show that this equivalence is rooted in mesoscale symmetries that exist in these webs. Certain eigenvectors of the Jacobian describing dynamical modes of the system, such as specific instabilities or responses to perturbations, localize on these symmetric motifs. On the one hand this means that by removing a symmetry from the network one obtains a system which has identical dynamics except for the removal of the localized mode. This explains the previously observed equivalence. On the other hand it means that we can identify dynamical modes that only depend on the symmetric motif. Symmetric structures thus provide an example for mesoscale network motifs having distinct and exact implications for the dynamics.

  20. Cold domes over the warm pool: a study of the properties of cold domes produced by mesoscale convective systems during TOGA COARE 

    E-Print Network [OSTI]

    Caesar, Kathy-Ann Lois

    1995-01-01

    , and wind speeds in the cold domes. Unique to this project is that low-level altitude flight legs ranged from 35 m to 300 m. Composite soundings of the inflow environment were constructed using flight level data from the NOAA P3s, the NCAR Electra...

  1. From Multi-Sensor Tracking of Sea Surface Films to Mesoscale and Sub-Mesoscale Sea Surface Current Fields

    E-Print Network [OSTI]

    Hamburg,.Universität

    From Multi-Sensor Tracking of Sea Surface Films to Mesoscale and Sub-Mesoscale Sea Surface Current, Bundesstr. 53, 20146 Hamburg, Germany ABSTRACT The knowledge about mesoscale and sub-mesoscale sea surface to investigate mesoscale and sub-mesoscale turbulent features like eddies, particularly in coastal waters

  2. Mesoscale Metallic Pyramids with Nanoscale Tips

    E-Print Network [OSTI]

    Odom, Teri W.

    Mesoscale Metallic Pyramids with Nanoscale Tips Joel Henzie, Eun-Soo Kwak, and Teri W. Odom generate free-standing mesoscale metallic pyramids composed of one or more materials and having nanoscale tips (radii of curvature of less than 2 nm). Mesoscale holes (100-300 nm) in a chromium film are used

  3. MESOSCALE AVERAGING OF NUCLEATION AND GROWTH MODELS

    E-Print Network [OSTI]

    Ferguson, Thomas S.

    MESOSCALE AVERAGING OF NUCLEATION AND GROWTH MODELS MARTIN BURGER , VINCENZO CAPASSO , AND LIVIO-Kolmogorov relations for the degree of crystallinity. By relating the computation of expected values to mesoscale averaging, we obtain a suitable description of the process at the mesoscale. We show how the variance

  4. Mesoscale Model Development and the Meteorological Community

    E-Print Network [OSTI]

    Mass, Clifford F.

    Mesoscale Model Development and the Meteorological Community Cliff Mass University of Washington: Although the U.S. remains a leader in mesoscale model development and application, the community is not fulfilling its potential. The resources of the U.S. mesoscale forecasting community are considerable

  5. Diagnosis of Ocean Mesoscale Eddy Tracer Fluxes

    E-Print Network [OSTI]

    Fox-Kemper, Baylor

    Diagnosis of Ocean Mesoscale Eddy Tracer Fluxes Baylor Fox-Kemper U. Colorado-Boulder, with Scott - 10,000 km, yrs->centuries) => resolved · Mesoscale variability (10 - 100 km, mo -> yrs) => resolved) => parameterized Boundary Layer Models Mesoscale resolving models Climate models Submesoscale variability Coupling

  6. TENURE-TRACK FACULTY POSITION Mesoscale Meteorology

    E-Print Network [OSTI]

    Birner, Thomas

    TENURE-TRACK FACULTY POSITION ­ Mesoscale Meteorology Colorado State University The Department or associate level faculty position specializing in mesoscale meteorology. Exceptionally qualified candidates in linking models and/or theory with observations for the study of mesoscale processes. The successful

  7. Mesoscale simulations of surfactant dissolution and mesophase formation

    E-Print Network [OSTI]

    P. Prinsen; P. B. Warren; M. A. J. Michels

    2002-04-22

    The evolution of the contact zone between pure surfactant and solvent has been studied by mesoscale simulation. It is found that mesophase formation becomes diffusion controlled and follows the equilibrium phase diagram adiabatically almost as soon as individual mesophases can be identified, corresponding to times in real systems of order 10 microseconds.

  8. Dynamics and generation mechanisms of mesoscale structures in tokamak edge plasmas

    SciTech Connect (OSTI)

    Krasheninnikov, S. I. [University of California at San Diego, 9500 Gilman Drive, La Jolla, California 92093 (United States); Smolyakov, A. I. [University of Saskatchewan, 116 Science Place, Saskatoon, Saskatchewan S7N 5E2 (Canada)

    2008-05-15

    Intermittent convective-like plasma transport associated with mesoscale coherent structures extended along the magnetic field lines (''blobs'') is often dominant at the edge of tokamaks, stellarators, and linear devices. Blobs can travel a large distance toward the wall ({approx}10 cm and larger) and strongly enhance both edge plasma energy and particle transport and plasma-wall interactions. The dynamics of blobs and blob generation mechanisms are discussed in this paper.

  9. Numerical modeling of roll structures in mesoscale vortexes over the Black Sea

    E-Print Network [OSTI]

    Iarova, D A

    2014-01-01

    This paper is a case study of horizontal atmospheric rolls that formed over the Black Sea on 16 August 2007. The rolls were discovered in WRF modeling results for a mesoscale cyclone that originated over the sea on 15 August 2007. The roll formation mechanisms, such as Rayleigh-Benard convective instability, dynamic instability, advection and stretching of vertical velocity field inhomogeneities, are considered. It is shown that indeed convective instability played an important role in the roll formation but dynamic instability did not occur. In order to distinguish other possible mechanisms of the roll formation numerical experiments were performed. In these experiments sea surface temperature in the initial conditions was decreased in order to prevent convective instability. Even though convective instability was suppressed roll-like structures still appeared in the modeling results, although their height and circulation velocity were smaller than in the control run. It was found that these structures were ...

  10. Reactor Engineering: Experimental Investigation of Alpha Convection

    SciTech Connect (OSTI)

    Usman, Shoaib

    2012-10-12

    Natural convection, Rayleigh-Bernard convection, Transient convection and Conduction convection transition.

  11. Meso-scale turbulence in living fluids

    E-Print Network [OSTI]

    Wensink, Henricus H; Heidenreich, Sebastian; Drescher, Knut; Goldstein, Raymond E; Löwen, Hartmut; Yeomans, Julia M

    2012-01-01

    Turbulence is ubiquitous, from oceanic currents to small-scale biological and quantum systems. Self-sustained turbulent motion in microbial suspensions presents an intriguing example of collective dynamical behavior amongst the simplest forms of life, and is important for fluid mixing and molecular transport on the microscale. The mathematical characterization of turbulence phenomena in active non-equilibrium fluids proves even more difficult than for conventional liquids or gases. It is not known which features of turbulent phases in living matter are universal or system-specific, or which generalizations of the Navier-Stokes equations are able to describe them adequately. Here, we combine experiments, particle simulations, and continuum theory to identify the statistical properties of self-sustained meso-scale turbulence in active systems. To study how dimensionality and boundary conditions affect collective bacterial dynamics, we measured energy spectra and structure functions in dense Bacillus subtilis su...

  12. Mesoscale Eddies in the Gulf of Alaska: Observations and Implications

    E-Print Network [OSTI]

    Rovegno, Peter

    2012-01-01

    Chao, Y. 2012. Modeling the mesoscale eddy field in the GulfShriver, J. F. 2001. Mesoscale variability in the boundaryof the Gulf of Alaska mesoscale circulation. Progress in

  13. Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatistical Output Perturbation

    E-Print Network [OSTI]

    Raftery, Adrian

    Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatistical Output. This is typically not feasible for mesoscale weather prediction carried out locally by organizations without by simulating realizations of the geostatistical model. The method is applied to 48-hour mesoscale forecasts

  14. MESOSCALE THEORY OF GRAINS AND CELLS: POLYCRYSTALS & PLASTICITY

    E-Print Network [OSTI]

    Sethna, James P.

    MESOSCALE THEORY OF GRAINS AND CELLS: POLYCRYSTALS & PLASTICITY A Dissertation Presented RIGHTS RESERVED #12;MESOSCALE THEORY OF GRAINS AND CELLS: POLYCRYSTALS & PLASTICITY Surachate Limkumnerd, continuum explanation for the evolution of dislocations into sharp walls. We present here a mesoscale theory

  15. Dynamic Filtering and Mining Triggers in Mesoscale Meteorology Forecasting

    E-Print Network [OSTI]

    Plale, Beth

    Dynamic Filtering and Mining Triggers in Mesoscale Meteorology Forecasting Nithya N. Vijayakumar {rramachandran, xli}@itsc.uah.edu Abstract-- Mesoscale meteorology forecasting as a data driven application Triggers, Data Mining, Stream Processing, Meteorology Forecasting I. INTRODUCTION Mesoscale meteorologists

  16. Mesoscale & Microscale Meteorological Division / NCAR WRF Nature Run

    E-Print Network [OSTI]

    Michalakes, John

    Mesoscale & Microscale Meteorological Division / NCAR WRF Nature Run John Michalakes Josh Hacker overview and petascale issues Nature run methodology Results and conclusion #12;Mesoscale & Microscale's atmosphere #12;Mesoscale & Microscale Meteorological Division / NCAR Description of Science · Kinetic energy

  17. Optically Directed Assembly of Continuous Mesoscale Filaments...

    Office of Scientific and Technical Information (OSTI)

    Optically Directed Assembly of Continuous Mesoscale Filaments Bahns, J. T.; Sankaranarayanan, S. K. R. S.; Gray, S. K.; Chen, L. Not Available American Physical Society None USDOE...

  18. Convection towers

    DOE Patents [OSTI]

    Prueitt, M.L.

    1996-01-16

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

  19. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1995-01-01

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

  20. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1994-01-01

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

  1. Convection towers

    DOE Patents [OSTI]

    Prueitt, Melvin L. (Los Alamos, NM)

    1996-01-01

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

  2. Ecospace: Prediction of Mesoscale Spatial Patterns in Trophic

    E-Print Network [OSTI]

    Pauly, Daniel

    Ecospace: Prediction of Mesoscale Spatial Patterns in Trophic Relationships of Exploited Ecosystems Springer-Verlag 539 Walters, C., D. Pauly and V. Christensen. 1999. Ecospace: Prediction of mesoscale

  3. Mesoscale Simulations of Particulate Flows with Parallel Distributed...

    Office of Scientific and Technical Information (OSTI)

    Mesoscale Simulations of Particulate Flows with Parallel Distributed Lagrange Multiplier Technique Citation Details In-Document Search Title: Mesoscale Simulations of Particulate...

  4. Mesoscale simulations of particulate flows with parallel distributed...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Mesoscale simulations of particulate flows with parallel distributed Lagrange multiplier technique Citation Details In-Document Search Title: Mesoscale simulations...

  5. Mesoscale Modeling Framework Design: Subcontract Report | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Mesoscale Modeling Framework Design: Subcontract Report Citation Details In-Document Search Title: Mesoscale Modeling Framework Design: Subcontract Report You are accessing a...

  6. STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS...

    Office of Scientific and Technical Information (OSTI)

    STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS Anter El-Azab 36 MATERIALS SCIENCE dislocation dynamics; mesoscale deformation of metals; crystal mechanics...

  7. Effects of Moist Froude Number and CAPE on a Conditionally Unstable Flow over a Mesoscale Mountain Ridge

    E-Print Network [OSTI]

    Chen, Shu-Hua

    Effects of Moist Froude Number and CAPE on a Conditionally Unstable Flow over a Mesoscale Mountain- dimensional mountain ridge in order to investigate the propagation and types of cloud precipitation systems unstable flow passing over a two-dimensional mesoscale mountain ridge. The characteristics of these flow

  8. Faculty Positions Department of Earth, Atmospheric, and Planetary Sciences

    E-Print Network [OSTI]

    Kihara, Daisuke

    of hazardous weather phenomena, such as tornadoes, mesoscale convective systems, and winter storms. Climate

  9. Towards a Fine-Resolution Global Coupled Climate System for Prediction...

    Office of Scientific and Technical Information (OSTI)

    58 GEOSCIENCES climate, numerical modeling, earth system model, ocean, sea-ice, mesoscale eddies climate, numerical modeling, earth system model, ocean, sea-ice, mesoscale...

  10. Mesoscale Engineering of Nanocomposite Nonlinear Optical Materials

    SciTech Connect (OSTI)

    Afonso, C.N.; Feldman, L.C.; Gonella, F.; Haglund, R.F.; Luepke, G.; Magruder, R.H.; Mazzoldi, P.; Osborne, D.H.; Solis, J.; Zuhr, R.A.

    1999-11-01

    Complex nonlinear optical materials comprising elemental, compound or alloy quantum dots embedded in appropriate dielectric or semiconducting hosts may be suitable for deployment in photonic devices. Ion implantation, ion exchange followed by ion implantation, and pulsed laser deposition have ail been used to synthesize these materials. However, the correlation between the parameters of energetic-beam synthesis and the nonlinear optical properties is still very rudimentary when one starts to ask what is happening at nanoscale dimensions. Systems integration of complex nonlinear optical materials requires that the mesoscale materials science be well understood within the context of device structures. We discuss the effects of beam energy and energy density on quantum-dot size and spatial distribution, thermal conductivity, quantum-dot composition, crystallinity and defects - and, in turn, on the third-order optical susceptibility of the composite material. Examples from recent work in our laboratories are used to illustrate these effects.

  11. Mesoscale Characterization of Coupled Hydromechanical Behavior of a Fractured Porous Slope in Response to Free Water-Surface Movement

    E-Print Network [OSTI]

    Guglielmi, Y.

    2008-01-01

    Mesoscale Characterization of Coupled Hydromechanicalinstrumented for mesoscale hydraulic and mechanicalwords: Fracture; Rock slope; Mesoscale; In situ poroelastic

  12. Convection towers

    DOE Patents [OSTI]

    Prueitt, M.L.

    1994-02-08

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

  13. Linking atomistic and mesoscale simulations of nanocrystalline materials : quantitative validation for the case of grain growth.

    SciTech Connect (OSTI)

    Moldovan, D.; Wolf, D.; Phillpot, S. R.; Materials Science Division; Louisiana State Univ.

    2003-11-01

    Using grain growth in nanocrystalline palladium as a simple case study, we demonstrate how a novel mesoscale approach for simulating microstructural evolution in polycrystalline materials can be validated directly against atomic-level simulations of the same system. We first describe molecular dynamics simulations of grain growth in a columnar model microstructure. The atomic-level insights into the grain-growth mechanism gained from these simulations, particularly in the role of grain rotations, are captured theoretically for incorporation into the mesoscale approach, in which the objects evolving in space and time are the grain boundaries and grain junctions rather than the atoms. With all the input parameters to the mesoscale being physically well defined and obtained directly from the atomic-level simulations, the mesoscale simulations are fully prescribed. We find that the morphology of the mesoscale system evolves in an almost identical manner with that of the molecular dynamics simulation, demonstrating that the length- and time-scale linking has been performed correctly. When applied to systems containing large numbers of grains, the now validated mesoscale simulation approach allows the growth topology and long-time growth kinetics to be determined. As an outlook, we describe how the effects of applied stress can be incorporated.

  14. A Two-Case Examination of the Synoptic and Mesoscale Processes Supporting Vertical13 Superposition of the Polar and Subtropical Jets over North America14

    E-Print Network [OSTI]

    Martin, Jonathan E.

    of the Synoptic and Mesoscale Processes Supporting Vertical13 Superposition of the Polar and Subtropical Jets Madison, WI 5370623 acwinters@wisc.edu24 25 Keywords: Jet Streams; Ageostrophic Transverse Circulations; Convection26 Running Head: Processes Supporting Jet Superposition27 28 29 Submitted

  15. Molecule-Mimetic Chemistry and Mesoscale Self-Assembly

    E-Print Network [OSTI]

    Prentiss, Mara

    Molecule-Mimetic Chemistry and Mesoscale Self-Assembly NED B. BOWDEN, MARCUS WECK, INSUNG S. CHOI, and possible uses for these processes and assemblies.6-22 Mesoscale Self-Assembly (MESA) Mesoscale Self technically, and especially in physics, a mesoscale object is one whose dimensions are comparable to the scale

  16. Intercomparison of oceanic and atmospheric forced and coupled mesoscale simulations

    E-Print Network [OSTI]

    Boyer, Edmond

    Intercomparison of oceanic and atmospheric forced and coupled mesoscale simulations Part I: Surface Abstract. A mesoscale non-hydrostatic atmospheric model has been coupled with a mesoscale oceanic model current. In order to analyze the eect of mesoscale coupling, three simulations are compared: the ®rst one

  17. Analytical mesoscale modeling of aeolian sand transport

    E-Print Network [OSTI]

    Marc Lämmel; Anne Meiwald; Klaus Kroy

    2014-05-03

    We analyze the mesoscale structure of aeolian sand transport, based on a recently developed two-species continuum model. The calculated sand flux and important average characteristics of the grain trajectories are found to be in remarkable agreement with field and wind-tunnel data. We conclude that the essential mesoscale physics is insensitive to unresolved details on smaller scales and well captured by the coarse-grained analytical model, thus providing a sound basis for precise and numerically efficient mesoscale modeling of aeolian structure formation.

  18. Mapping mesoscale heterogeneity in the plastic deformation of a copper single crystal

    E-Print Network [OSTI]

    Magid, K. R.

    2009-01-01

    619. page 18 Mapping mesoscale heterogeneity in a deformedthese planes. page 36 Mapping mesoscale heterogeneity in aJanuary 2009, 77–107 Mapping mesoscale heterogeneity in the

  19. Effect of ocean mesoscale variability on the mean state of tropical Atlantic climate

    E-Print Network [OSTI]

    Seo, H; Jochum, M; Murtugudde, R; Miller, A J

    2006-01-01

    Effect of Ocean Mesoscale Variability on the Mean State ofthe effect of oceanic mesoscale features on the mean climatemodel, resolving oceanic mesoscale variability leads to a

  20. MESOSCALE SIMULATIONS OF POWDER COMPACTION

    SciTech Connect (OSTI)

    Lomov, Ilya; Fujino, Don; Antoun, Tarabay; Liu, Benjamin [Lawrence Livermore National Laboratory, P. O. Box 808, Livermore CA 94551 (United States)

    2009-12-28

    Mesoscale 3D simulations of shock compaction of metal and ceramic powders have been performed with an Eulerian hydrocode GEODYN. The approach was validated by simulating a well-characterized shock compaction experiment of a porous ductile metal. Simulation results using the Steinberg material model and handbook values for solid 2024 aluminum showed good agreement with experimental compaction curves and wave profiles. Brittle ceramic materials are not as well studied as metals, so a simple material model for solid ceramic (tungsten carbide) has been calibrated to match experimental compaction curves. Direct simulations of gas gun experiments with ceramic powders have been performed and showed good agreement with experimental data. The numerical shock wave profile has same character and thickness as that measured experimentally using VISAR. The numerical results show reshock states above the single-shock Hugoniot line as observed in experiments. We found that for good quantitative agreement with experiments 3D simulations are essential.

  1. Postulated Mesoscale Quantum of Internal Friction Hysteresis

    E-Print Network [OSTI]

    Randall D. Peters

    2004-05-27

    Evidence is provided, from yet another experiment, for the existence of a mesoscale quantum of internal friction hysteresis, having the value of the electron rest energy divided by the fine structure constant.

  2. Convective heater

    DOE Patents [OSTI]

    Thorogood, Robert M. (Macungie, PA)

    1986-01-01

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

  3. Meso-scale turbulence in living fluids

    E-Print Network [OSTI]

    Henricus H. Wensink; Jörn Dunkel; Sebastian Heidenreich; Knut Drescher; Raymond E. Goldstein; Hartmut Löwen; Julia M. Yeomans

    2012-08-21

    Turbulence is ubiquitous, from oceanic currents to small-scale biological and quantum systems. Self-sustained turbulent motion in microbial suspensions presents an intriguing example of collective dynamical behavior amongst the simplest forms of life, and is important for fluid mixing and molecular transport on the microscale. The mathematical characterization of turbulence phenomena in active non-equilibrium fluids proves even more difficult than for conventional liquids or gases. It is not known which features of turbulent phases in living matter are universal or system-specific, or which generalizations of the Navier-Stokes equations are able to describe them adequately. Here, we combine experiments, particle simulations, and continuum theory to identify the statistical properties of self-sustained meso-scale turbulence in active systems. To study how dimensionality and boundary conditions affect collective bacterial dynamics, we measured energy spectra and structure functions in dense Bacillus subtilis suspensions in quasi-2D and 3D geometries. Our experimental results for the bacterial flow statistics agree well with predictions from a minimal model for self-propelled rods, suggesting that at high concentrations the collective motion of the bacteria is dominated by short-range interactions. To provide a basis for future theoretical studies, we propose a minimal continuum model for incompressible bacterial flow. A detailed numerical analysis of the 2D case shows that this theory can reproduce many of the experimentally observed features of self-sustained active turbulence.

  4. Mesoscale Simulations of Power Compaction

    SciTech Connect (OSTI)

    Lomov, I; Fujino, D; Antoun, T; Liu, B

    2009-08-06

    Mesoscale 3D simulations of metal and ceramic powder compaction in shock waves have been performed with an Eulerian hydrocode GEODYN. The approach was validated by simulating shock compaction of porous well-characterized ductile metal using Steinberg material model. Results of the simulations with handbook values for parameters of solid 2024 aluminum have good agreement with experimental compaction curves and wave profiles. Brittle ceramic materials are not so well studied as metals, so material model for ceramic (tungsten carbide) has been fitted to shock compression experiments of non-porous samples and further calibrated to match experimental compaction curves. Direct simulations of gas gun experiments with ceramic powder have been performed and showed good agreement with experimental data. Numerical shock wave profile has same character and thickness as measured with VISAR. Numerical results show reshock states above the single-shock Hugoniot line also observed in experiments. They found that to receive good quantitative agreement with experiment it is essential to perform 3D simulations.

  5. Glider Path-Planning for Optimal Sampling of Mesoscale Eddies

    E-Print Network [OSTI]

    Smith, Ryan N.

    Glider Path-Planning for Optimal Sampling of Mesoscale Eddies Daniel Hernandez1 , Ryan Smith2 these, mesoscale eddies are of particular interest due to the relevance they have in many oceano

  6. ForPeerReview A 'Boscastle-type' quasi-stationary convective system over

    E-Print Network [OSTI]

    Plant, Robert

    of Meteorology Kirshbaum, Daniel; McGill University, Department of Atmospheric and Oceanic Sciences Plant, Robert on 21 July 2010. This system was remarkably similar in its location and structure to one which caused: . . . Copyright c 0000 Royal Meteorological Society Q. J. R. Meteorol. Soc. 00: 2­25 (0000) Prepared using qjrms4

  7. Evaluation of Cloud-resolving and Limited Area Model Intercomparison Simulations using TWP-ICE Observations. Part 1: Deep Convective Updraft Properties

    SciTech Connect (OSTI)

    Varble, A. C.; Zipser, Edward J.; Fridlind, Ann; Zhu, Ping; Ackerman, Andrew; Chaboureau, Jean-Pierre; Collis, Scott M.; Fan, Jiwen; Hill, Adrian; Shipway, Ben

    2014-12-27

    Ten 3D cloud-resolving model (CRM) simulations and four 3D limited area model (LAM) simulations of an intense mesoscale convective system observed on January 23-24, 2006 during the Tropical Warm Pool – International Cloud Experiment (TWP-ICE) are compared with each other and with observed radar reflectivity fields and dual-Doppler retrievals of vertical wind speeds in an attempt to explain published results showing a high bias in simulated convective radar reflectivity aloft. This high bias results from ice water content being large, which is a product of large, strong convective updrafts, although hydrometeor size distribution assumptions modulate the size of this bias. Snow reflectivity can exceed 40 dBZ in a two-moment scheme when a constant bulk density of 100 kg m-3 is used. Making snow mass more realistically proportional to area rather than volume should somewhat alleviate this problem. Graupel, unlike snow, produces high biased reflectivity in all simulations. This is associated with large amounts of liquid water above the freezing level in updraft cores. Peak vertical velocities in deep convective updrafts are greater than dual-Doppler retrieved values, especially in the upper troposphere. Freezing of large rainwater contents lofted above the freezing level in simulated updraft cores greatly contributes to these excessive upper tropospheric vertical velocities. Strong simulated updraft cores are nearly undiluted, with some showing supercell characteristics. Decreasing horizontal grid spacing from 900 meters to 100 meters weakens strong updrafts, but not enough to match observational retrievals. Therefore, overly intense simulated updrafts may partly be a product of interactions between convective dynamics, parameterized microphysics, and large-scale environmental biases that promote different convective modes and strengths than observed.

  8. Mesoscale morphologies in polymer thin films.

    SciTech Connect (OSTI)

    Ramanathan, M.; Darling, S. B. (Center for Nanoscale Materials)

    2011-06-01

    In the midst of an exciting era of polymer nanoscience, where the development of materials and understanding of properties at the nanoscale remain a major R&D endeavor, there are several exciting phenomena that have been reported at the mesoscale (approximately an order of magnitude larger than the nanoscale). In this review article, we focus on mesoscale morphologies in polymer thin films from the viewpoint of origination of structure formation, structure development and the interaction forces that govern these morphologies. Mesoscale morphologies, including dendrites, holes, spherulites, fractals and honeycomb structures have been observed in thin films of homopolymer, copolymer, blends and composites. Following a largely phenomenological level of description, we review the kinetic and thermodynamic aspects of mesostructure formation outlining some of the key mechanisms at play. We also discuss various strategies to direct, limit, or inhibit the appearance of mesostructures in polymer thin films as well as an outlook toward potential areas of growth in this field of research.

  9. A Mesoscale Diffusion Model in Population Genetics with

    E-Print Network [OSTI]

    O'Leary, Michael

    ' & $ % A Mesoscale Diffusion Model in Population Genetics with Dynamic Fitness Mike O'Leary Towson University Judith R. Miller Georgetown University 1 #12;A mesoscale diffusion model in population genetics that dominance and epistasis are absent. April 28, 2005 Mike O'Leary and Judith Miller Slide 2 #12;A mesoscale

  10. Mesoscale analysis of segmental dynamics in microphase-segregated polyurea

    E-Print Network [OSTI]

    Grujicic, Mica

    Mesoscale analysis of segmental dynamics in microphase- segregated polyurea M. Grujicic · B-atom molecular dynamics techniques. To overcome this problem, mesoscale coarse-grain simulation methods of constituent atom-size particles. Within the mesoscale methods, on the other hand, this atomistic description

  11. Computational upscaling of inertia effects from porescale to mesoscale

    E-Print Network [OSTI]

    Peszynska, Malgorzata

    Computational upscaling of inertia effects from porescale to mesoscale Malgorzata Peszy´nska1 for computational upscaling of flow from porescale (microscale) to lab scale (mesoscale). In particular, we solve laboratory for porous me- dia which delivers data needed for mesoscale simulations by performing microscale

  12. Simulation and characterization of the Adriatic Sea mesoscale variability

    E-Print Network [OSTI]

    Cushman-Roisin, Benoit

    Simulation and characterization of the Adriatic Sea mesoscale variability Benoit Cushman-Roisin,1 resolve the mesoscale variability because the grid size falls below the first baroclinic deformation in two larger-scale models. The present simulations demonstrate that the DieCAST model allows mesoscale

  13. GLOBAL PATTERN OF MESOSCALE VARIABILITY IN SEA SURFACE HEIGHT

    E-Print Network [OSTI]

    Kaplan, Alexey

    GLOBAL PATTERN OF MESOSCALE VARIABILITY IN SEA SURFACE HEIGHT AND ITS DYNAMICAL CAUSES Alexey separate the mesoscale variability of sea surface heights into its spatial and temporal components of mesoscale variability in different areas to dynamical causes. Major portion of it can be explained

  14. MESOSCALE EDDIES Peter B. Rhines, University of Washington,

    E-Print Network [OSTI]

    MESOSCALE EDDIES Peter B. Rhines, University of Washington, School of Oceanography, Box 357940, Seattle, WA 98195 7940, USA Copyright ^ 2001 Academic Press doi:10.1006/rwos.2001.0143 Mesoscale eddies that strongly feel viscosity, to `mesoscale eddies' that strongly feel the Earth's rota- tion, to great `gyres

  15. Accessing biology's toolbox for the mesoscale biofabrication of soft matter

    E-Print Network [OSTI]

    Raghavan, Srinivasa

    Accessing biology's toolbox for the mesoscale biofabrication of soft matter Gregory F. Payne,bf James N. Culverag and William E. Bentley*ab Biology is a master of mesoscale science, possessing will provide a biocompatible approach to mesoscale science and yield products that are safe, sustainable

  16. AN URBAN SURFACE EXCHANGE PARAMETERISATION FOR MESOSCALE MODELS

    E-Print Network [OSTI]

    AN URBAN SURFACE EXCHANGE PARAMETERISATION FOR MESOSCALE MODELS ALBERTO MARTILLI1, , ALAIN CLAPPIER. A scheme to represent the impact of urban buildings on airflow in mesoscale atmospheric models is presented the presence of the buildings. The parameterisation is introduced into a mesoscale model and tested

  17. Identification of a mesoscale model with multiscale experimental observations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Identification of a mesoscale model with multiscale experimental observations M.T. Nguyen, C and at mesoscale within the framework of a heterogeneous microstruc- ture which is modeled by a random elastic measurements of the displacement fields at macroscale and at mesoscale performed with only a single specimen

  18. HYBRID DECADE-MEAN GLOBAL SEA LEVEL WITH MESOSCALE RESOLUTION

    E-Print Network [OSTI]

    HYBRID DECADE-MEAN GLOBAL SEA LEVEL WITH MESOSCALE RESOLUTION Nikolai A. Maximenko1 and Pearn P of twin-satellite mission GRACE and mesoscale sea level tilt derived from the momentum balance as seen 55 #12;sea level exhibits excellent accuracy on mesoscale, but may contain significant systematic

  19. WIND ATLAS FOR EGYPT: MEASUREMENTS, MICRO-AND MESOSCALE MODELLING

    E-Print Network [OSTI]

    WIND ATLAS FOR EGYPT: MEASUREMENTS, MICRO- AND MESOSCALE MODELLING Niels G. Mortensen1 , Jens atlas based on long-term reanalysis data and a mesoscale model (KAMM). The mean absolute error comparing atlas based on long-term reanalysis data and a mesoscale model, KAMM. The observations have been

  20. Report on the use of stability parameters and mesoscale

    E-Print Network [OSTI]

    Report on the use of stability parameters and mesoscale modelling in short-term prediction Jake Nielsen, Henrik Madsen, John Tøfting Title: Report on the use of stability parameters and mesoscale. Mesoscale modelling has been carried out using KAMM at this location. The characteristics of the measured

  1. Particle-Based Mesoscale Hydrodynamic Techniques

    E-Print Network [OSTI]

    Hiroshi Noguchi; Norio Kikuchi; Gerhard Gompper

    2006-10-31

    Dissipative particle dynamics (DPD) and multi-particle collision (MPC) dynamics are powerful tools to study mesoscale hydrodynamic phenomena accompanied by thermal fluctuations. To understand the advantages of these types of mesoscale simulation techniques in more detail, we propose new two methods, which are intermediate between DPD and MPC -- DPD with a multibody thermostat (DPD-MT), and MPC-Langevin dynamics (MPC-LD). The key features are applying a Langevin thermostat to the relative velocities of pairs of particles or multi-particle collisions, and whether or not to employ collision cells. The viscosity of MPC-LD is derived analytically, in very good agreement with the results of numerical simulations.

  2. A study of mesoscale gravity waves over the North Atlantic with satellite observations and a mesoscale model

    E-Print Network [OSTI]

    A study of mesoscale gravity waves over the North Atlantic with satellite observations and a mesoscale model Dong L. Wu Jet Propulsion Laboratory, California Institute of Technology, Pasadena and compare AMSU-A observations to simulations from a mesoscale model (MM5). The simulated gravity waves

  3. A Method to Merge WSR-88D Data with ARM SGP Millimeter Cloud Radar Data by Studying Deep Convective Systems

    E-Print Network [OSTI]

    Dong, Xiquan

    A Method to Merge WSR-88D Data with ARM SGP Millimeter Cloud Radar Data by Studying Deep Convective A decade of collocated Atmospheric Radiation Measurement Program (ARM) 35-GHz Millimeter Cloud Radar (MMCR) and Weather Surveillance Radar-1988 Doppler (WSR-88D) data over the ARM Southern Great Plains (SGP) site have

  4. Modeling the Interaction between Cumulus Convection and Linear Gravity Waves Using a Limited-Domain Cloud SystemResolving Model

    E-Print Network [OSTI]

    Kuang, Zhiming

    of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts (Manuscript received 10 January they exhibit many of the basic features of the observed 2-day waves. The simulated convectively coupled waves study each indi- vidual horizontal wavenumber separately. This meth- odology is explained in more detail

  5. ARM - Midlatitude Continental Convective Clouds

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

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

    2012-01-19

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

  6. ARM - Midlatitude Continental Convective Clouds

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

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

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

  7. Phase behavior and mesoscale solubilization in aqueous solutions of hydrotropes

    E-Print Network [OSTI]

    Deepa Subramanian; Mikhail A. Anisimov

    2013-09-27

    Hydrotropes are amphiphilic molecules that are too small to spontaneously form equilibrium structures in aqueous solutions, but form dynamic, noncovalent assemblies, referred to as clusters. In the presence of a hydrophobic compound, these clusters seem to get stabilized leading to the formation of long-lived, highly stable mesoscopic droplets, a phenomenon that we call mesoscale solubilization. In this work, we focus on the unusual mesoscopic properties of aqueous solutions of a nonionic hydrotrope, namely tertiary butyl alcohol (TBA), on addition of various hydrophobic compounds. Aqueous TBA solutions, in about 3 to 8 mol percent TBA concentration range and about 0 to 25 deg. C temperature range, show the presence of short-ranged (0.5 nm), short-lived (tens of picoseconds) molecular clusters which result in anomalies of the thermodynamic properties. These clusters are transient but do not relax by diffusion, thus distinctly different from conventional concentration fluctuations. In this concentration and temperature range, upon the addition of a third (more hydrophobic) component to TBA-water solutions, long-lived mesoscopic droplets of about 100 nm size are observed. In this work, we clarify the ambiguity behind the definition of solubility and elucidate the phenomenon of mesoscale solubilization. A systematic study of the macro and meso phase behavior of three ternary systems TBA-water-propylene oxide, TBA-water-isobutyl alcohol, and TBA-water-cyclohexane has been carried out. We differentiate between molecular solubility, mesoscale solubilization, and macroscopic phase separation. We have confirmed that practically stable aqueous colloids can be created from small molecules, without addition of surfactants or polymers. Such kind of novel materials may find applications in the design of various processes and products, ranging from pharmaceuticals to cosmetics and agrochemicals.

  8. Mechanical Engineering students learn how to design and build things that move, including machines, technological systems, robots, aircrafts, automobiles, artificial limbs and consumer products. They also learn how to generate and develop energy.

    E-Print Network [OSTI]

    Bustamante, Fabián E.

    YEARS 1. Life-cycle analysis of energy systems 2. Controlling legged locomotion 3. Precision mesoscale

  9. Macroscale modeling and mesoscale observations of plasma density structures in the polar cap

    SciTech Connect (OSTI)

    Basu, S. [Phillips Lab., Hanscom Air Force Base, MA (United States)] [Phillips Lab., Hanscom Air Force Base, MA (United States); Basu, S. [National Science Foundation, Arlington, VA (United States)] [National Science Foundation, Arlington, VA (United States); Sojka, J.J. [Utah State Univ., Logan, UT (United States)] [and others] [Utah State Univ., Logan, UT (United States); and others

    1995-04-15

    The seasonal and UT variation of mesoscale structures (10 km - 100 m) in the central polar cap has been obtained from an analysis of 250-MHz intensity scintillation observations made at Thule, Greenland. It has been established earlier that mesoscale structures causing scintillations of satellite signals may develop at the edges of macroscale structures (several hundred km) such as discrete polar cap plasma density enhancements or patches through the gradient drift instability process. As such, the authors examined the seasonal and UT variation of polar cap patches simulated by using the USU Time Dependent Ionospheric Model (TDIM) under conditions of southward B{sub z}. A fairly remarkable similarity is found between the scintillation observations and the model predictions of patch occurrence. For instance, both the patch and scintillation occurrences are minimized during the winter solstice (northern hemisphere) between 0800-1200 UT while also having their largest seasonal intensity between 2000-2400 UT. Little UT dependence of patches and scintillations is seen at equinox with high intensity being observed throughout the day, while during local summer the intensity of macroscale patches and mesoscale irregularities are found to be a minimum at all UT. These results indicate that macroscale features in the polar cap are routinely associated with plasma instabilities giving rise to smaller scale structures and that the specific patch formation mechanism assumed in the simulation is consistent with the observations. This ability to bridge between macroscale modeling and mesoscale observations provides a natural framework for the modeling of mesoscale structures themselves. This mesoscale modeling, in turn, can be utilized in a variety of radar and communication systems applications in the polar region. 25 refs., 3 figs.

  10. Using Mesoscale Weather Model Output as Boundary Conditions for Atmospheric Large-Eddy Simulations and Wind-Plant Aerodynamic Simulations (Presentation)

    SciTech Connect (OSTI)

    Churchfield, M. J.; Michalakes, J.; Vanderwende, B.; Lee, S.; Sprague, M. A.; Lundquist, J. K.; Moriarty, P. J.

    2013-10-01

    Wind plant aerodynamics are directly affected by the microscale weather, which is directly influenced by the mesoscale weather. Microscale weather refers to processes that occur within the atmospheric boundary layer with the largest scales being a few hundred meters to a few kilometers depending on the atmospheric stability of the boundary layer. Mesoscale weather refers to large weather patterns, such as weather fronts, with the largest scales being hundreds of kilometers wide. Sometimes microscale simulations that capture mesoscale-driven variations (changes in wind speed and direction over time or across the spatial extent of a wind plant) are important in wind plant analysis. In this paper, we present our preliminary work in coupling a mesoscale weather model with a microscale atmospheric large-eddy simulation model. The coupling is one-way beginning with the weather model and ending with a computational fluid dynamics solver using the weather model in coarse large-eddy simulation mode as an intermediary. We simulate one hour of daytime moderately convective microscale development driven by the mesoscale data, which are applied as initial and boundary conditions to the microscale domain, at a site in Iowa. We analyze the time and distance necessary for the smallest resolvable microscales to develop.

  11. Tracking tropical cloud systems for the diagnosis of simulations by the weather research and forecasting (WRF) model

    SciTech Connect (OSTI)

    Vogelmann, A.M.; Lin, W.; Cialella, A.; Luke, E. P.; Jensen, M. P.; Zhang, M. H.; Boer, E.

    2010-06-27

    To aid in improving model parameterizations of clouds and convection, we examine the capability of models, using explicit convection, to simulate the life cycle of tropical cloud systems in the tropical warm pool. The cloud life cycle is determined using a satellite cloud tracking algorithm (Boer and Ramanathan, J. Geophys. Res., 1997), and the statistics are compared to those of simulations using the Weather Research and Forecasting (WRF) Model. Using New York Blue, a Blue Gene/L supercomputer that is co-operated by Brookhaven and Stony Brook, simulations are run at a resolution comparable to the observations. Initial results suggest that the organization of the mesoscale convective systems is particularly sensitive to the cloud microphysics parameterization used.

  12. SUMMARY: When temperature differences across the system create a gravitation-ally unstable stratification (top-heavy fluid), convection sets in. Two kinds of con-

    E-Print Network [OSTI]

    Cushman-Roisin, Benoit

    temperatures and pressures are tabulated below. Table 7.1: Values of physical properties of fresh water (at 10- ally unstable stratification (top-heavy fluid), convection sets in. Two kinds of con- vection are distinguished here: top-bottom convection and penetrative convection. The chapter closes with remarks

  13. A modified convective/stratiform partitioning algorithm 

    E-Print Network [OSTI]

    Listemaa, Steven Alan

    1998-01-01

    by using different radar reflectivity-rail-ate relationships. Several authors have developed their own convective-stratiform partitioning, but each had its limitations. An algorithm has been developed which partitions precipitating systems...

  14. Mesoscale harmonic analysis of homogenous dislocation nucleation

    E-Print Network [OSTI]

    Asad Hasan; Craig E. Maloney

    2012-05-08

    We perform atomistic computer simulations to study the mechanism of homogeneous dislocation nucleation in two dimensional (2D) hexagonal crystalline films during indentation with a circular nanoindenter. The nucleation process is governed by the vanishing of the energy associated with a single normal mode. This critical mode is largely confined to a single plane of adjacent atoms. For fixed film thickness, L, the spatial extent, \\xi, of the critical mode grows with indenter radius, R. For fixed R/L, the spatial extent \\xi, grows roughly as \\xi ~ L^0.4. We, furthermore, perform a mesoscale analysis to determine the lowest energy normal mode for mesoscale regions of varying radius, r_{meso}, centered on the critical mode's core. The energy, \\lambda_{meso}, of the lowest normal mode in the meso-region decays very rapidly with r_{meso} and \\lambda_{meso} ~= 0 for r_{meso} >~ \\xi. The lowest normal mode shows a spatial extent, \\xi_{meso}, which has a sublinear power-law increase with r_{meso} for r_{meso} mesoscale analysis gives good estimates for the energy and spatial extent of the critical mode \\emph{only} for r_{meso} >~ 1.5 \\xi. In this sense homogeneous dislocation nucleation should be understood as a quasi-local phenomenon.

  15. MESOSCALE OCEANOGRAPHY Instructors: Igor Kamenkovich, Arthur Mariano and Donald B. Olson, with other contributions

    E-Print Network [OSTI]

    Miami, University of

    MESOSCALE OCEANOGRAPHY Instructors: Igor Kamenkovich, Arthur Mariano and Donald B. Olson of ocean mesoscale variability, including its properties in different oceanic regimes, the dynamics will learn basic concepts on ocean mesoscale processes and perspectives on current research topics from

  16. Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics with reaction ensemble Monte Carlo.

    E-Print Network [OSTI]

    Lisal, Martin

    Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics a mesoscale simulation technique, called the reaction ensemble dissipative particle dynamics RxDPD method. Coarse-grained, particle- based mesoscale models that retain only the most essential features

  17. Impact of Agricultural Practice on Regional Climate in a Coupled Land Surface Mesoscale Model

    E-Print Network [OSTI]

    Cooley, H.S.; Riley, W.J.; Torn, M.S.; He, Y.

    2004-01-01

    winter wheat belt on the mesoscale environment, Monthlygeneration Penn State/NCAR mesoscale model (MM5), NCAR,in a Coupled Land Surface Mesoscale Model H.S. Cooley Energy

  18. Detecting and characterizing mesoscale and submesoscale structures of Mediterranean water from joint seismic

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Click Here for Full Article Detecting and characterizing mesoscale and submesoscale structures mesoscale and submesoscale structures of Mediterranean water from joint seismic and hydrographic the imaged structures in terms of mesoscale and submesoscale eddies, of homogeneous layers and of lateral

  19. From Quanta to the Continuum: Opportunities for Mesoscale Science...

    Office of Scientific and Technical Information (OSTI)

    Quanta to the Continuum: Opportunities for Mesoscale Science Crabtree, George Argonne National Lab. (ANL), Argonne, IL (United States); Sarrao, John Los Alamos National Lab....

  20. Challenge of Dynamic Mesoscale Imaging Barnes, Cris William ...

    Office of Scientific and Technical Information (OSTI)

    The Matter-Radiation Interactions in Extremes Project, and the Challenge of Dynamic Mesoscale Imaging Barnes, Cris William Los Alamos National Laboratory; Barber, John L. Los...

  1. Quanta to the Continuum: Opportunities for Mesoscale Science...

    Office of Scientific and Technical Information (OSTI)

    Quanta to the Continuum: Opportunities for Mesoscale Science Sarrao, John L Los Alamos National Laboratory; Crabtree, George Argonne National Laboratory 36 MATERIALS SCIENCE;...

  2. Meso-Scale during Electron Beam Additive Manufacturing Chen,...

    Office of Scientific and Technical Information (OSTI)

    Thermal Properties and Beam-Particle Interaction at Meso-Scale during Electron Beam Additive Manufacturing Chen, Jian ORNL ORNL; Zheng, Lili ORNL ORNL; Feng, Zhili...

  3. Numerical Simulation in Applied Geophysics. From the Mesoscale to ...

    E-Print Network [OSTI]

    Local variations in the fluid and solid matrix properties, fine layering, fractures and craks at the mesoscale (on the order of centimeters) are common in the earth's ...

  4. From deterministic to stochastic, from mesoscale to macroscopic

    E-Print Network [OSTI]

    Title: From deterministic to stochastic, from mesoscale to macroscopic: multiscale modeling of grain growth Abstract: Many problems in science and engineering ...

  5. STATISTICAL MECHANICS MODELING OF MESOSCALE DEFORMATION IN METALS...

    Office of Scientific and Technical Information (OSTI)

    and computational modeling of dislocation dynamics of mesoscale deformation of metal single crystals. Specifically, the work aimed to implement a continuum statistical...

  6. Mesoscale Modeling of Fuel Swelling and Restructuring: Coupling...

    Office of Scientific and Technical Information (OSTI)

    Conference: Mesoscale Modeling of Fuel Swelling and Restructuring: Coupling Microstructure evolution and Mechanical Localization. Citation Details In-Document Search Title:...

  7. Lagrangian study of transport and mixing in a mesoscale eddy street

    E-Print Network [OSTI]

    S. V. Prants; M. V. Budyansky; V. I. Ponomarev; M. Yu. Uleysky

    2012-02-02

    We use dynamical systems approach and Lagrangian tools to study surface transport and mixing of water masses in a selected coastal region of the Japan Sea with moving mesoscale eddies associated with the Primorskoye Current. Lagrangian trajectories are computed for a large number of particles in an interpolated velocity field generated by a numerical regional multi-layer eddy-resolving circulation model. We compute finite-time Lyapunov exponents for a comparatively long period of time by the method developed and plot the Lyapunov synoptic map quantifying surface transport and mixing in that region. This map uncovers the striking flow structures along the coast with a mesoscale eddy street and repelling material lines. We propose new Lagrangian diagnostic tools --- the time of exit of particles off a selected box, the number of changes of the sign of zonal and meridional velocities --- to study transport and mixing by a pair of strongly interacting eddies often visible at sea-surface temperature satellite images in that region. We develop a technique to track evolution of clusters of particles, streaklines and material lines. The Lagrangian tools used allow us to reveal mesoscale eddies and their structure, to track different phases of the coastal flow, to find inhomogeneous character of transport and mixing on mesoscales and submesoscales and to quantify mixing by the values of exit times and the number of times particles wind around the eddy's center.

  8. A Coupling Methodology for Mesoscale-informed Nuclear Fuel Performance Codes

    SciTech Connect (OSTI)

    Michael Tonks; Derek Gaston; Cody Permann; Paul Millett; Glen Hansen; Dieter Wolf

    2010-10-01

    This study proposes an approach for capturing the effect of microstructural evolution on reactor fuel performance by coupling a mesoscale irradiated microstructure model with a finite element fuel performance code. To achieve this, the macroscale system is solved in a parallel, fully coupled, fully-implicit manner using the preconditioned Jacobian-free Newton Krylov (JFNK) method. Within the JFNK solution algorithm, microstructure-influenced material parameters are calculated by the mesoscale model and passed back to the macroscale calculation. Due to the stochastic nature of the mesoscale model, a dynamic fitting technique is implemented to smooth roughness in the calculated material parameters. The proposed methodology is demonstrated on a simple model of a reactor fuel pellet. In the model, INL’s BISON fuel performance code calculates the steady-state temperature profile in a fuel pellet and the microstructure-influenced thermal conductivity is determined with a phase field model of irradiated microstructures. This simple multiscale model demonstrates good nonlinear convergence and near ideal parallel scalability. By capturing the formation of large mesoscale voids in the pellet interior, the multiscale model predicted the irradiation-induced reduction in the thermal conductivity commonly observed in reactors.

  9. ARM Convective Available Potential Energy (CAPE), Convective Inhibition (CIN) Product

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

    Jensen, Michael

    2014-04-10

    ARM soundings are used to determine Convective Available Potential Energy (CAPE), Convective Inhibition (CIN) and associated properties, using the following relationships;

  10. ARM Convective Available Potential Energy (CAPE), Convective Inhibition (CIN) Product

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

    Jensen, Michael

    ARM soundings are used to determine Convective Available Potential Energy (CAPE), Convective Inhibition (CIN) and associated properties, using the following relationships;

  11. Mesoscale regulation comes from the bottom-up: intertidal interactions between consumers

    E-Print Network [OSTI]

    Nielsen, Karina J.

    REPORT Mesoscale regulation comes from the bottom-up: intertidal interactions between consumers variation in nutrient supply to shift community structure over mesoscales. Keywords Macroalgae, upwelling

  12. Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics with reaction

    E-Print Network [OSTI]

    Lisal, Martin

    Mesoscale simulation of polymer reaction equilibrium: Combining dissipative particle dynamics. R. Smith, J. Chem. Phys. 125, 16490 2006 , a mesoscale simulation technique for studying polymer

  13. NASA-TM-III642 Design of Inielligent Mesoscale Periodic Array

    E-Print Network [OSTI]

    Asher, Sanford A.

    i" /} , NASA-TM-III642 Design of Inielligent Mesoscale Periodic Array Structures Utilizing Smart *National Research Council hitrodoetion Mesoscale Periodic Arlay Structures (MPAS, also known as crystalline

  14. Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle material

    E-Print Network [OSTI]

    Microscale and mesoscale discrete models for dynamic fracture of structures built of brittle are derived either at microscale with random distribution of material properties or at a mesoscale

  15. A unified morphological description of Nafion membranes from SAXS and mesoscale simulations

    E-Print Network [OSTI]

    Elliott, James

    A unified morphological description of Nafion membranes from SAXS and mesoscale simulations James A with mesoscale simulations of the morphology of Nafion using Dissipative Particle Dynamics (DPD) parameterized

  16. Mesoscale Theory of Grains and Cells: Crystal Plasticity and Coarsening Surachate Limkumnerd* and James P. Sethna

    E-Print Network [OSTI]

    Sethna, James P.

    Mesoscale Theory of Grains and Cells: Crystal Plasticity and Coarsening Surachate Limkumnerd a mesoscale theory of dislocation motion. It provides a quantitative description of deformation and rotation

  17. Adler R. F., G. J. Huffman, A. Chang, R. Ferraro, P. Xie, J. Janowiak, B. Rudolf, U. Schneider, S. Curtis, D. Bolvin, A. Gruber, J. Susskind, P. Arkin, E. Nelkin, 2003 ; The version-2 Global

    E-Print Network [OSTI]

    Boyer, Edmond

    . Hydrometeorol., 4, pp. 1147-1167. Houze, R. A., Jr., 2004:Mesoscale convective systems. Rev. Geophys., 42, 10

  18. Engineering mesoscale structures with distinct dynamical implications in networks of delay-coupled delay oscillators

    E-Print Network [OSTI]

    Anne-Ly Do; Johannes Höfener; Thilo Gross

    2012-07-05

    The dynamics of networks of interacting systems depends intricately on the interaction topology. When the dynamics is explored, generally the whole topology has to be considered. However, we show that there are certain mesoscale subgraphs that have precise and distinct consequences for the system-level dynamics. In particular, if meso-scale symmetries are present then eigenvectors of the Jacobian localise on the symmetric subgraph and the corresponding eigenvalues become insensitive to the topology outside the subgraph. Hence, dynamical instabilities associated with these eigenvalues can be analyzed without considering the topology outside the subgraph. While such instabilities are thus generated entirely in small network subgraphs, they generally do not remain confined to the subgraph once the instability sets in and thus have system-level consequences. Here we illustrate the analytical investigation of such instabilities in an ecological meta-population model consisting of a network of delay-coupled delay oscillators.

  19. Mesoscale modelling of polyelectrolyte electrophoresis

    E-Print Network [OSTI]

    Kai Grass; Christian Holm

    2009-02-11

    The electrophoretic behaviour of flexible polyelectrolyte chains ranging from single monomers up to long fragments of hundred repeat units is studied by a mesoscopic simulation approach. Abstracting from the atomistic details of the polyelectrolyte and the fluid, a coarse-grained molecular dynamics model connected to a mesoscopic fluid described by the Lattice Boltzmann approach is used to investigate free-solution electrophoresis. Our study demonstrates the importance of hydrodynamic interactions for the electrophoretic motion of polyelectrolytes and quantifies the influence of surrounding ions. The length-dependence of the electrophoretic mobility can be understood by evaluating the scaling behavior of the effective charge and the effective friction. The perfect agreement of our results with experimental measurements shows that all chemical details and fluid structure can be safely neglected, and a suitable coarse-grained approach can yield an accurate description of the physics of the problem, provided that electrostatic and hydrodynamic interactions between all entities in the system, i.e., the polyelectrolyte, dissociated counterions, additional salt and the solvent, are properly accounted for. Our model is able to bridge the single molecule regime of a few nm up to macromolecules with contour lengths of more than 100 nm, a length scale that is currently not accessible to atomistic simulations.

  20. Radiative-convective instability

    E-Print Network [OSTI]

    Wing, Allison A.

    Radiative-moist-convective equilibrium (RCE) is a simple paradigm for the statistical equilibrium the earth's climate would exhibit in the absence of lateral energy transport. It has generally been assumed that for a given ...

  1. Mesoscale phenomena in solutions of 3-methylpyridine, heavy water, and an antagonistic salt

    E-Print Network [OSTI]

    Jan Leys; Deepa Subramanian; Eva Rodezno; Boualem Hammouda; Mikhail A. Anisimov

    2013-08-22

    We have investigated controversial issues regarding the mesoscale behavior of 3-methylpyridine (3MP), heavy water, and sodium tetraphenylborate (NaBPh4) solutions by combining results obtained from dynamic light scattering (DLS) and small-angle neutron scattering (SANS). We have addressed three questions: (i) what is the origin of the mesoscale inhomogeneities (order of 100 nm in size) manifested by the "slow mode" in DLS? (ii) Is the periodic structure observed from SANS an inherent property of this system? (iii) What is the universality class of critical behavior in this system? Our results confirm that the "slow mode" observed from DLS experiments corresponds to long-lived, highly stable mesoscale droplets (order of 100 nm in size), which occur only when the solute (3MP) is contaminated by hydrophobic impurities. SANS data confirm the presence of a periodic structure with a periodicity of about 10 nm. This periodic structure cannot be eliminated by nanopore filtration and thus is indeed an inherent solution property. The critical behavior of this system, in the range of concentration and temperatures investigated by DLS experiments, indicates that the criticality belongs to the universality class of the 3-dimensional Ising model.

  2. Soil moisture in complex terrain: quantifying effects on atmospheric boundary layer flow and providing improved surface boundary conditions for mesoscale models

    E-Print Network [OSTI]

    Daniels, Megan Hanako

    2010-01-01

    groundwater, land-surface, and mesoscale atmospheric model-and modification of mesoscale circulations. , Mon. Wea.J. Davis, The effects of mesoscale surface heterogeneity on

  3. Mesoscale Atmospheric Dispersion, 2001, Ed. Z. Boybeyi, WIT Publications, Southampton, UK, Advances in Air Pollution, Vol 9, p. 424.

    E-Print Network [OSTI]

    Raman, Sethu

    in Air Pollution, Vol 9, p. 424. Chapter 9 Numerical modeling of gas deposition and bi- directional surface­atmosphere exchanges in mesoscale air pollution systems Devdutta S. Niyogi & Sethu Raman North to develop deposition flux estimates in air pollution models. An interesting scenario also develops when

  4. THE APPLICATION OF AN EVOLUTIONARY ALGORITHM TO THE OPTIMIZATION OF A MESOSCALE METEOROLOGICAL MODEL

    SciTech Connect (OSTI)

    Werth, D.; O'Steen, L.

    2008-02-11

    We show that a simple evolutionary algorithm can optimize a set of mesoscale atmospheric model parameters with respect to agreement between the mesoscale simulation and a limited set of synthetic observations. This is illustrated using the Regional Atmospheric Modeling System (RAMS). A set of 23 RAMS parameters is optimized by minimizing a cost function based on the root mean square (rms) error between the RAMS simulation and synthetic data (observations derived from a separate RAMS simulation). We find that the optimization can be efficient with relatively modest computer resources, thus operational implementation is possible. The optimization efficiency, however, is found to depend strongly on the procedure used to perturb the 'child' parameters relative to their 'parents' within the evolutionary algorithm. In addition, the meteorological variables included in the rms error and their weighting are found to be an important factor with respect to finding the global optimum.

  5. Lagrangian study of transport and mixing in a mesoscale eddy street

    E-Print Network [OSTI]

    Prants, S V; Ponomarev, V I; Uleysky, M Yu; 10.1016/j.ocemod.2011.02.008

    2012-01-01

    We use dynamical systems approach and Lagrangian tools to study surface transport and mixing of water masses in a selected coastal region of the Japan Sea with moving mesoscale eddies associated with the Primorskoye Current. Lagrangian trajectories are computed for a large number of particles in an interpolated velocity field generated by a numerical regional multi-layer eddy-resolving circulation model. We compute finite-time Lyapunov exponents for a comparatively long period of time by the method developed and plot the Lyapunov synoptic map quantifying surface transport and mixing in that region. This map uncovers the striking flow structures along the coast with a mesoscale eddy street and repelling material lines. We propose new Lagrangian diagnostic tools --- the time of exit of particles off a selected box, the number of changes of the sign of zonal and meridional velocities --- to study transport and mixing by a pair of strongly interacting eddies often visible at sea-surface temperature satellite imag...

  6. Mesoscale Quantization and Self-Organized Stability

    E-Print Network [OSTI]

    Randall D. Peters

    2005-06-16

    In the world of technology, one of the most important forms of friction is that of rolling friction. Yet it is one of the least studied of all the known forms of energy dissipation. In the present experiments we investigate the oscillatory free-decay of a rigid cube, whose side-length is less than the diameter of the rigid cylinder on which it rests. The resulting free-decay is one of harmonic motion with damping. The non-dissipative character of the oscillation yields to a linear differential equation; however, the damping is found to involve more than a deterministic nonlinearity. Dominated by rolling friction, the damping is sensitive to the material properties of the contact surfaces. For `clean' surfaces of glass on glass, the decay shows features of mesoscale quantization and self-organized stability.

  7. Mesoscale Elucidation of Biofilm Shear Behavior

    E-Print Network [OSTI]

    Barai, Pallab; Mukherjee, Partha P

    2015-01-01

    Formation of bacterial colonies as biofilm on the surface/interface of various objects has the potential to impact not only human health and disease but also energy and environmental considerations. Biofilms can be regarded as soft materials, and comprehension of their shear response to external forces is a key element to the fundamental understanding. A mesoscale model has been presented in this article based on digitization of a biofilm microstructure. Its response under externally applied shear load is analyzed. Strain stiffening type behavior is readily observed under high strain loads due to the unfolding of chains within soft polymeric substrate. Sustained shear loading of the biofilm network results in strain localization along the diagonal direction. Rupture of the soft polymeric matrix can potentially reduce the intercellular interaction between the bacterial cells. Evolution of stiffness within the biofilm network under shear reveals two regions: a) initial increase in stiffness due to strain stiffe...

  8. Segmentation and Tracking of Mesoscale Eddies in Numeric Ocean Models Vishal Sood, Bin John, Ramprasad Balasubramanian and Amit Tandon*

    E-Print Network [OSTI]

    Tandon, Amit

    Segmentation and Tracking of Mesoscale Eddies in Numeric Ocean Models Vishal Sood, Bin John suggested that the mesoscale eddies and mesoscale features play a strong role in carrying heat poleward oceanographers an invaluable tool to assess mesoscale eddies and the Lagrangian characteristics of this mesoscale

  9. Atomic-Scale Observations Aid Mesoscale Catalyst Design | ornl...

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

    Materials Characterization Atomic-Scale Observations Aid Mesoscale Catalyst Design April 08, 2015 Fig.1. Z-contrast STEM image shows the Mo-V-Te-Ta oxide catalyst. (a) "M1-like"...

  10. Phase Effects on Mesoscale Object X-ray Absorption Images

    SciTech Connect (OSTI)

    Martz, Jr., H E; Aufderheide, M B; Barty, A; Lehman, S K; Kozioziemski, B J; Schneberk, D J

    2004-09-24

    At Lawrence Livermore National Laboratory particular emphasis is being placed on the nondestructive characterization (NDC) of 'mesoscale' objects.[Martz and Albrecht 2003] We define mesoscale objects as objects that have mm extent with {micro}m features. Here we confine our discussions to x-ray imaging methods applicable to mesoscale object characterization. The goal is object recovery algorithms including phase to enable emerging high-spatial resolution x-ray imaging methods to ''see'' inside or image mesoscale-size materials and objects. To be successful our imaging characterization effort must be able to recover the object function to one micrometer or better spatial resolution over a few millimeters field-of-view with very high contrast.

  11. Observations, dynamics and predictability of the mesoscale convective vortex event of 10-13 June 2003 

    E-Print Network [OSTI]

    Hawblitzel, Daniel Patrick

    2006-08-16

    2.13 11 June 600 hPa observations from the NOAA Wind Profiler Network............................................................................................. 37 2.14 WSR88D reflectivity from 1500 UTC 11 June to 0600 UTC 12 June...), height (blue, in meters) and wind (one full barb denotes 10 knots)............................................... 55 2.29 600 hPa BAMEX dropsonde observations of temperature (red, in degrees Celsius), dewpoint (green), height (blue...

  12. Mesoscale ensemble-based data assimilation and parameter estimation 

    E-Print Network [OSTI]

    Aksoy, Altug

    2005-11-01

    -1 MESOSCALE ENSEMBLE-BASED DATA ASSIMILATION AND PARAMETER ESTIMATION A Dissertation by ALTUG AKSOY Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR... OF PHILOSOPHY August 2005 Major Subject: Atmospheric Sciences MESOSCALE ENSEMBLE-BASED DATA ASSIMILATION AND PARAMETER ESTIMATION A Dissertation by ALTUG AKSOY Submitted to the Office of Graduate Studies of Texas A...

  13. Analysis of azimuthal mode dynamics of mesoscale eddies 

    E-Print Network [OSTI]

    McCalpin, John David

    1984-01-01

    ANALYSIS OF AZIMUTHAL MODE DYNAMICS OF MESOSCALE EDDIES A Thesis by UOHN DAVID MCCALPIN Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 1984... Major Subject: Oceanography ANALYSIS OF AZIMUTHAL MODE DYNAMICS OF MESOSCALE EDDIES A Thesis by JOHN DAVID MCCALPIN Approved as to style and content by: rew . as ano (Chairman of Committee) o ert . ei (Member) uy . rancesc &ni (Member) Robert...

  14. Convective Cloud Lifecycles Lunchtime seminar

    E-Print Network [OSTI]

    Plant, Robert

    Convective Cloud Lifecycles Lunchtime seminar 19th May 2009 Bob Plant Department of Meteorology, University of Reading, UK #12;Introduction Obtain life cycle statistics for clouds in CRM simulations Why Conclusions Convective Cloud Lifecycles ­ p.1/3 #12;Why bother? Convective Cloud Lifecycles ­ p.2/3 #12;Some

  15. Planar Fabrication of a Mesoscale Voice Coil Actuator Benjamin Goldberg, Michael Karpelson, Onur Ozcan, and Robert J. Wood

    E-Print Network [OSTI]

    Wood, Robert

    Planar Fabrication of a Mesoscale Voice Coil Actuator Benjamin Goldberg, Michael Karpelson, Onur, USA Abstract-- Mesoscale robots are devices with characteristic dimensions in the centimeter limited. We present a mesoscale voice coil actuator (VCA) with favorable scaling characteristics

  16. Fully-coupled engineering and mesoscale simulations of thermal conductivity in UO2 fuel using an implicit multiscale approach

    SciTech Connect (OSTI)

    Michael Tonks; Derek Gaston; Cody Permann; Paul Millett; Glen Hansen; Chris Newman

    2009-08-01

    Reactor fuel performance is sensitive to microstructure changes during irradiation (such as fission gas and pore formation). This study proposes an approach to capture microstructural changes in the fuel by a two-way coupling of a mesoscale phase field irradiation model to an engineering scale, finite element calculation. This work solves the multiphysics equation system at the engineering-scale in a parallel, fully-coupled, fully-implicit manner using a preconditioned Jacobian-free Newton Krylov method (JFNK). A sampling of the temperature at the Gauss points of the coarse scale is passed to a parallel sequence of mesoscale calculations within the JFNK function evaluation phase of the calculation. The mesoscale thermal conductivity is calculated in parallel, and the result is passed back to the engineering-scale calculation. As this algorithm is fully contained within the JFNK function evaluation, the mesoscale calculation is nonlinearly consistent with the engineering-scale calculation. Further, the action of the Jacobian is also consistent, so the composite algorithm provides the strong nonlinear convergence properties of Newton's method. The coupled model using INL's \\bison\\ code demonstrates quadratic nonlinear convergence and good parallel scalability. Initial results predict the formation of large pores in the hotter center of the pellet, but few pores on the outer circumference. Thus, the thermal conductivity is is reduced in the center of the pellet, leading to a higher internal temperature than that in an unirradiated pellet.

  17. Predicting reptile distributions at the mesoscale: relation to climate and topography

    E-Print Network [OSTI]

    Richner, Heinz

    Predicting reptile distributions at the mesoscale: relation to climate and topography Antoine at a mesoscale level. A more detailed knowledge of these relationships, in combination with maps of the potential

  18. Chromatin Ionic Atmosphere Analyzed by a Mesoscale Electrostatic Hin Hark Gan

    E-Print Network [OSTI]

    Schlick, Tamar

    Chromatin Ionic Atmosphere Analyzed by a Mesoscale Electrostatic Approach Hin Hark Gan and Tamar an electrostatic model to handle multivalent ions and compute the ionic distribution around a mesoscale chromatin

  19. Course: Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale

    E-Print Network [OSTI]

    Santos, Juan

    Course: Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale Professor variations in the fluid and solid matrix properties, fine layering, frac- tures and craks at the mesoscale

  20. DOI: 10.1002/adma.200601882 Spontaneous Formation of Mesoscale Polymer Patterns

    E-Print Network [OSTI]

    Lin, Zhiqun

    DOI: 10.1002/adma.200601882 Spontaneous Formation of Mesoscale Polymer Patterns in an Evaporating of intriguing, ordered structures. Herein, we report on the spontaneous formation of well-or- ganized mesoscale

  1. A distributional approach to the geometry of 2D dislocations at the mesoscale

    E-Print Network [OSTI]

    Lisbon, University of

    A distributional approach to the geometry of 2D dislocations at the mesoscale Part A: General introduce the meso-scale as defined by some average distance between the dislocations. The laws governing

  2. Simulation of Indentation Fracture in Crystalline Materials Using Mesoscale Self-Assembly

    E-Print Network [OSTI]

    Hutchinson, John W.

    Simulation of Indentation Fracture in Crystalline Materials Using Mesoscale Self-Assembly Venkat R Abstract: A new physical model based on mesoscale self-assembly is developed to simulate indentation

  3. Atomic Force Microscopy of Photosystem II and Its Unit Cell Clustering Quantitatively Delineate the Mesoscale

    E-Print Network [OSTI]

    Geissler, Phillip

    the Mesoscale Variability in Arabidopsis Thylakoids Bibiana Onoa1 , Anna R. Schneider2 , Matthew D. Brooks3 Quantitatively Delineate the Mesoscale Variability in Arabidopsis Thylakoids. PLoS ONE 9(7): e101470. doi:10

  4. Mass and charge flow in nanopores: numerical simulation via mesoscale models

    E-Print Network [OSTI]

    Cecconi, Fabio

    Mass and charge flow in nanopores: numerical simulation via mesoscale models Mauro Chinappi1 at nanoscale is here addressed via a recent developed mesoscale approach. In particular the flow

  5. Structure of polyamidoamide dendrimers up to limiting generations: A mesoscale description

    E-Print Network [OSTI]

    Goddard III, William A.

    Structure of polyamidoamide dendrimers up to limiting generations: A mesoscale description Prabal K, while reducing the degrees of freedom by tenfold. This mesoscale description has allowed us to study

  6. Author's personal copy Mesoscale modeling of electric double layer capacitors with three-dimensional

    E-Print Network [OSTI]

    Pilon, Laurent

    Author's personal copy Mesoscale modeling of electric double layer capacitors with three Mesoscale modeling Mesoporous electrodes a b s t r a c t This paper presents general mathematical

  7. Mesoscale Modeling of a Li-Ion Polymer Cell Chia-Wei Wanga,

    E-Print Network [OSTI]

    Sastry, Ann Marie

    Mesoscale Modeling of a Li-Ion Polymer Cell Chia-Wei Wanga, * and Ann Marie Sastrya,b,c, *,z, the study reported critical data required for mesoscale numerical simulation, including ionic con- ductivity

  8. Zxodes scapularis (Acari:Ixodidae) Deer Tick Mesoscale Populations in Natural Areas: Effects of Deer, Area,

    E-Print Network [OSTI]

    Duffy, David Cameron

    Zxodes scapularis (Acari:Ixodidae) Deer Tick Mesoscale Populations in Natural Areas: Effects al. 1990al) and macroscales (eastern United States [Daniels et al. 19931).We examined the mesoscale

  9. Momentum, Heat, and Neutral Mass Transport in Convective Atmospheric Pressure Plasma-Liquid Systems and Implications for Aqueous Targets

    E-Print Network [OSTI]

    Lindsay, Alexander; Slikboer, Elmar; Shannon, Steven; Graves, David

    2015-01-01

    There is a growing interest in the study of plasma-liquid interactions with application to biomedicine, chemical disinfection, agriculture, and other fields. This work models the momentum, heat, and neutral species mass transfer between gas and aqueous phases in the context of a streamer discharge; the qualitative conclusions are generally applicable to plasma-liquid systems. The problem domain is discretized using the finite element method. The most interesting and relevant model result for application purposes is the steep gradients in reactive species at the interface. At the center of where the reactive gas stream impinges on the water surface, the aqueous concentrations of OH and ONOOH decrease by roughly 9 and 4 orders of magnitude respectively within 50 $\\mu$m of the interface. Recognizing the limited penetration of reactive plasma species into the aqueous phase is critical to discussions about the therapeutic mechanisms for direct plasma treatment of biological solutions. Other interesting results fro...

  10. Plains Elevated Convection at Night (PECAN) Experiment Science Plan

    SciTech Connect (OSTI)

    Turner, D; Parsons, D; Geerts, B

    2015-03-01

    The Plains Elevated Convection at Night (PECAN) experiment is a large field campaign that is being supported by the National Science Foundation (NSF) with contributions from the National Oceanic and Atmospheric Administration (NOAA), the National Atmospheric and Space Administration (NASA), and the U.S. Department of Energy (DOE). The overarching goal of the PECAN experiment is to improve the understanding and simulation of the processes that initiate and maintain convection and convective precipitation at night over the central portion of the Great Plains region of the United States (Parsons et al. 2013). These goals are important because (1) a large fraction of the yearly precipitation in the Great Plains comes from nocturnal convection, (2) nocturnal convection in the Great Plains is most often decoupled from the ground and, thus, is forced by other phenomena aloft (e.g., propagating bores, frontal boundaries, low-level jets [LLJ], etc.), (3) there is a relative lack of understanding how these disturbances initiate and maintain nocturnal convection, and (4) this lack of understanding greatly hampers the ability of numerical weather and climate models to simulate nocturnal convection well. This leads to significant uncertainties in predicting the onset, location, frequency, and intensity of convective cloud systems and associated weather hazards over the Great Plains.

  11. Distribution and Habitat Associations of Billfish and Swordfish Larvae across Mesoscale Features in the Gulf

    E-Print Network [OSTI]

    Rooker, Jay R.

    Distribution and Habitat Associations of Billfish and Swordfish Larvae across Mesoscale Features additive models (GAMs). Mesoscale features in the NGoM affected the distribution and abundance of billfish and Swordfish Larvae across Mesoscale Features in the Gulf of Mexico. PLoS ONE 7(4): e34180. doi:10.1371/journal

  12. Mixed Layer Cooling in Mesoscale Oceanic Eddies during Hurricanes Katrina and Rita

    E-Print Network [OSTI]

    Miami, University of

    Mixed Layer Cooling in Mesoscale Oceanic Eddies during Hurricanes Katrina and Rita BENJAMIN JAIMES. Introduction Isotherm topography and energetic geostrophic flow in mesoscale oceanic features in the Gulf. 2000; Shay et al. 2000). The dependence of hurricane-induced OML cooling on the presence of mesoscale

  13. ATM678, Mesoscale Dynamics, Spring 2014 Class time: TR 11:30am to 1pm

    E-Print Network [OSTI]

    Moelders, Nicole

    ATM678, Mesoscale Dynamics, Spring 2014 Class time: TR 11:30am to 1pm Classroom: Elvy auditorium, Akasofu 319 Course Description: The class provides a comprehensive explanation of mesoscale air motions ­ their phenology, basic physics and mechanisms, why they build and how mesoscale motions interact with the micro

  14. Mesoscale-resolving simulations of summer and winter bora events in the Adriatic Sea

    E-Print Network [OSTI]

    Cushman-Roisin, Benoit

    Mesoscale-resolving simulations of summer and winter bora events in the Adriatic Sea Benoit CushmanCAST model on a 1.2-min grid (about 2-km resolution) and resolve the mesoscale variability because the grid-Roisin, B., and K. A. Korotenko (2007), Mesoscale-resolving simulations of summer and winter bora events

  15. Near-Inertial Wave Wake of Hurricanes Katrina and Rita over Mesoscale Oceanic Eddies

    E-Print Network [OSTI]

    Miami, University of

    Near-Inertial Wave Wake of Hurricanes Katrina and Rita over Mesoscale Oceanic Eddies BENJAMIN; Jaimes and Shay 2009, hereafter JS09). These robust mesoscale oceanic features are present at any time (Jaimes 2009). This mesoscale ocean variability imposed important dynamical constraints on the OML

  16. Analysis of a mesoscale infiltration and water seepage test in unsaturated fractured rock: Spatial variabilities

    E-Print Network [OSTI]

    Zhou, Quanlin

    Analysis of a mesoscale infiltration and water seepage test in unsaturated fractured rock: Spatial 2006 Abstract A mesoscale (21 m in flow distance) infiltration and seepage test was recently conducted flow in fractured rock at mesoscale or a larger scale is not necessarily conditional explicitly

  17. Mesoscale circulations and atmospheric CO2 variations in the Tapajos Region, Para, Brazil

    E-Print Network [OSTI]

    Collett Jr., Jeffrey L.

    Mesoscale circulations and atmospheric CO2 variations in the Tapajo´s Region, Para´, Brazil Lixin; published 2 November 2005. [1] We have investigated mesoscale circulations and atmospheric CO2 variations over a heterogeneous landscape of forests, pastures, and large rivers during the Santare´m Mesoscale

  18. Mesoscale eddies northeast of the Hawaiian archipelago from satellite altimeter observations

    E-Print Network [OSTI]

    Qiu, Bo

    Mesoscale eddies northeast of the Hawaiian archipelago from satellite altimeter observations; published 16 March 2010. [1] Enhanced mesoscale eddy activity northeast of the Hawaiian archipelago by 5° longitude subregions revealed the dominant mesoscale periods ranging from 90 days near 18°N

  19. On the role of mesoscale eddies in the ventilation of Antarctic intermediate water

    E-Print Network [OSTI]

    Fischlin, Andreas

    On the role of mesoscale eddies in the ventilation of Antarctic intermediate water Zouhair Lachkar Mesoscale eddies CFC-11 Ventilation Southern Ocean a b s t r a c t The spatial distribution of Antarctic and ventilation are substantially affected by mesoscale eddies. To diagnose the role of eddies, we made global CFC

  20. Small and mesoscale properties of a substorm onset auroral arc H. U. Frey,1

    E-Print Network [OSTI]

    California at Berkeley, University of

    Small and mesoscale properties of a substorm onset auroral arc H. U. Frey,1 O. Amm,2 C. C. Chaston; revised 22 June 2010; accepted 28 June 2010; published 7 October 2010. [1] We present small and mesoscale. Good agreement could be reached for the mesoscale arc properties. A qualitative analysis

  1. Self-Assembly of Mesoscale Isomers: The Role of Pathways and Degrees of Freedom

    E-Print Network [OSTI]

    Menon, Govind

    Self-Assembly of Mesoscale Isomers: The Role of Pathways and Degrees of Freedom Shivendra Pandey1 geometric path sampling and a mesoscale experimental model to investigate the self-assembly of a model. Citation: Pandey S, Johnson D, Kaplan R, Klobusicky J, Menon G, et al. (2014) Self-Assembly of Mesoscale

  2. Seasonal Mesoscale and Submesoscale Eddy Variability along the North Pacific Subtropical Countercurrent

    E-Print Network [OSTI]

    Qiu, Bo

    Seasonal Mesoscale and Submesoscale Eddy Variability along the North Pacific Subtropical abundant in mesoscale eddies, but also exhibits prominent submesoscale eddy features. Output from a 1 the seasonal STCC variability in the mesoscale versus submesoscale ranges. Resolving the eddy scales of .150 km

  3. Deriving Mesoscale Surface Current Fields from Multi-Sensor Satellite Data , B. Seppke b

    E-Print Network [OSTI]

    Hamburg,.Universität

    Deriving Mesoscale Surface Current Fields from Multi-Sensor Satellite Data M. Gade a , B. Seppke b of mesoscale surface currents in the southestern Baltic Sea (Southern Baltic Proper). Marine surface films of the two-dimensional data sets may therefore allow for the calculation of mesoscale ocean current fields

  4. Sensitivity of Mesoscale Surface Dynamics to Surface Soil and Vegetation Contrasts over the Carolina Sandhills

    E-Print Network [OSTI]

    Raman, Sethu

    Sensitivity of Mesoscale Surface Dynamics to Surface Soil and Vegetation Contrasts over in mesoscale summertime precipitation over this region. Numerical simulations are analyzed to investigate the relationships between mesoscale surface dynamics and the transition from clay to sandy soils over this region

  5. Global Observations of Nonlinear Mesoscale Eddies Dudley B. Chelton, Michael G. Schlax and Roger M. Samelson

    E-Print Network [OSTI]

    Kurapov, Alexander

    Global Observations of Nonlinear Mesoscale Eddies Dudley B. Chelton, Michael G. Schlax and Roger M mesoscale variability in the global ocean. The prevalence of eddy-like structures with scales of O(100 km mesoscale features based on their SSH signatures yields 35,891 eddies with lifetimes 16 weeks. These long

  6. ATMOSPHERIC DUST AND MESOSCALE/MICROSCALE METEOROLOGY. A. Spiga1 , S.R. Lewis1

    E-Print Network [OSTI]

    Spiga, Aymeric

    ATMOSPHERIC DUST AND MESOSCALE/MICROSCALE METEOROLOGY. A. Spiga1 , S.R. Lewis1 , and F. For- get2 to advances in computational resources and modeling techniques. Note also that mesoscale modeling and Large: general circulation models, mesoscale models, microscale models [Large-Eddy Simulations]. Figure 1

  7. Mesoscale and clusters of synchrony in networks of bursting neurons Igor Belykh1

    E-Print Network [OSTI]

    Belykh, Igor

    Mesoscale and clusters of synchrony in networks of bursting neurons Igor Belykh1 and Martin Hasler2 with relatively large clusters, leading potentially to cluster synchronization at the mesoscale network level. We represent the microscale level, cooperative rhythms of neuronal subpopulations define the mesoscale level

  8. ach year across the US, mesoscale weather events--flash floods, tornadoes, hail,

    E-Print Network [OSTI]

    Plale, Beth

    E ach year across the US, mesoscale weather events--flash floods, tornadoes, hail, strong winds of mesoscale weather research; its disparate, high-volume data sets and streams; or the tremendous urgent need for a comprehensive national cyberinfrastructure in mesoscale meteorology--particularly one

  9. Mesoscale simulations of gravity waves during the 20082009 major stratospheric sudden warming

    E-Print Network [OSTI]

    Limpasuvan, Varavut

    Mesoscale simulations of gravity waves during the 2008­2009 major stratospheric sudden warming September 2011. [1] A series of 24 h mesoscale simulations (of 10 km horizontal and 400 m vertical. Yamashita (2011), Mesoscale simulations of gravity waves during the 2008­2009 major stratospheric sudden

  10. PHYSICAL REVIEW A 83, 043827 (2011) Quantum fluctuations and saturable absorption in mesoscale lasers

    E-Print Network [OSTI]

    Levi, Anthony F. J.

    2011-01-01

    PHYSICAL REVIEW A 83, 043827 (2011) Quantum fluctuations and saturable absorption in mesoscale in mesoscale lasers. The time evolution of the density matrix is obtained from numerical integration and field behavior of mesoscale lasers. Using only semiclassical master equations and specific device parameters

  11. Satellite observations of mesoscale ocean features and copropagating atmospheric surface fields in the tropical belt

    E-Print Network [OSTI]

    Xie, Shang-Ping

    Satellite observations of mesoscale ocean features and copropagating atmospheric surface fields speed and sea surface temperature (SST) over mesoscale ocean features in certain frontal regions. The aim of this study is to determine to what extent mesoscale ocean dynamics modifies the surface wind

  12. Influence of mesoscale eddies on ichthyoplankton assemblages in the Gulf of Alaska

    E-Print Network [OSTI]

    Influence of mesoscale eddies on ichthyoplankton assemblages in the Gulf of Alaska ELIZABETH ATWOOD 98115, USA ABSTRACT Mesoscale eddies (100­200 km in diameter) propa- gating along the shelf in these eddies was examined using data from a cruise in 2005 that sampled three eastern Gulf of Alaska mesoscale

  13. CORIOLIS EFFECTS IN MESOSCALE SHALLOW LAYER FLOWS J. C. R. Hunt

    E-Print Network [OSTI]

    Hunt, Julian

    CORIOLIS EFFECTS IN MESOSCALE SHALLOW LAYER FLOWS J. C. R. Hunt ¢¡ £ ,A. Orr , D. Cresswell layer or inversion layer, is developed for idealised and steady, but typical, mesoscale atmospheric estimates for a wide range of perturbed mesoscale flows, especially where the surface conditions change

  14. CONVERGENCE AND STABILITY IN UPSCALING OF FLOW WITH INERTIA FROM PORESCALE TO MESOSCALE

    E-Print Network [OSTI]

    Peszynska, Malgorzata

    CONVERGENCE AND STABILITY IN UPSCALING OF FLOW WITH INERTIA FROM PORESCALE TO MESOSCALE MAl with inertia from porescale (microscale) to Darcy scale (lab scale, mesoscale). In particular, we solve Navier-Darcy model with inertia at mesoscale. 1. Introduction. In [1] we presented a proof-of-concept algorithm

  15. Melting and crystallization in Ni nanoclusters: The mesoscale regime Yue Qi and Tahir C agin

    E-Print Network [OSTI]

    Goddard III, William A.

    Melting and crystallization in Ni nanoclusters: The mesoscale regime Yue Qi and Tahir C¸ agin to a mesoscale nanocrystal regime well-defined bulk and surface properties above 750 atoms 2.7 nm . We find that the mesoscale nanocrystals melt via surface processes, leading to Tm,N Tm,bulk N 1/3 , dropping from Tm

  16. Modeled biogeochemical responses to mesoscale eddies in the South China Sea

    E-Print Network [OSTI]

    Xiu, Peng

    Modeled biogeochemical responses to mesoscale eddies in the South China Sea Peng Xiu1 and Fei Chai1] Mesoscale eddies are observed each year in the South China Sea (SCS); however, their contributions physicalbiogeochemical model to evaluate the eddy impact. We first track the modeled mesoscale eddies in the SCS

  17. PROBCAST: A Web-Based Portal to Mesoscale Probabilistic Forecasts Clifford Mass1

    E-Print Network [OSTI]

    Mass, Clifford F.

    1 PROBCAST: A Web-Based Portal to Mesoscale Probabilistic Forecasts Clifford Mass1 , Susan Joslyn over the Pacific Northwest. PROBCAST products are derived from the output of a mesoscale ensemble-processing of mesoscale, short-range ensembles. The NAS report also noted current deficiencies in the communication

  18. Author , Short title EFFECTS OF MESOSCALE TEXTURE ON APPARENT SURFACE GLOSS

    E-Print Network [OSTI]

    Ferwerda, James A.

    Author , Short title 1 EFFECTS OF MESOSCALE TEXTURE ON APPARENT SURFACE GLOSS James A. Ferwerda to it. We first measure both the microscale reflectance properties and mesoscale texture of flat, latex these images as stimuli in perceptual experiments to systematically study how surface mesoscale properties

  19. A Diagnostic Suite of Models for the Evaluation of Oceanic Mesoscale Eddy Parameterizations

    E-Print Network [OSTI]

    Fox-Kemper, Baylor

    A Diagnostic Suite of Models for the Evaluation of Oceanic Mesoscale Eddy Parameterizations by S. D of Oceanic Mesoscale Eddy Parameterizations written by S. D. Bachman has been approved for the Department and Oceanic Sciences) A Diagnostic Suite of Models for the Evaluation of Oceanic Mesoscale Eddy

  20. A new model to simulate the Martian mesoscale and microscale atmospheric circulation: Validation and first results

    E-Print Network [OSTI]

    Spiga, Aymeric

    A new model to simulate the Martian mesoscale and microscale atmospheric circulation: Validation) Mesoscale Model is a new versatile simulator of the Martian atmosphere and environment at horizontal scales, and photochemistry cycles. Since LMD-GCM large-scale simulations are also used to drive the mesoscale model

  1. Development of a Piezoelectrically-Actuated Mesoscale Robot Quadruped Michael Goldfarb, Michael Gogola, Gregory Fischer

    E-Print Network [OSTI]

    Simaan, Nabil

    Development of a Piezoelectrically-Actuated Mesoscale Robot Quadruped Michael Goldfarb, Michael approach that offers a high locomotive efficiency, and is therefore well suited to mesoscale robot design actuated mesoscale robot quadruped. The design described utilizes a lightly damped skeletal structure

  2. Persistence of iron limitation in the western subarctic Pacific SEEDS II mesoscale fertilization experiment

    E-Print Network [OSTI]

    Cochlan, William P.

    Persistence of iron limitation in the western subarctic Pacific SEEDS II mesoscale fertilization t The cumulative evidence from more than a dozen mesoscale iron-enrichment studies in high nitrate low chlorophyll diatoms, vary greatly among these mesoscale experiments even though similar amounts of iron were added

  3. Atomistic and Mesoscale Modeling of Dislocation B.S., Huazhong University of Science and Technology (1995)

    E-Print Network [OSTI]

    Cai, Wei

    1995-01-01

    Atomistic and Mesoscale Modeling of Dislocation Mobility by Wei Cai B.S., Huazhong University by . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sow-Hsin Chen Chairman, Department Committee on Graduate Students #12;2 #12;Atomistic and Mesoscale theories and simulations of dislocations in Si and BCC transition metals, with emphasis on the atomistic-mesoscale

  4. Deep-Sea Research I 53 (2006) 321332 Effects of mesoscale phytoplankton variability on the copepods

    E-Print Network [OSTI]

    Thomas, Andrew

    2006-01-01

    Deep-Sea Research I 53 (2006) 321­332 Effects of mesoscale phytoplankton variability encompassing the spring phytoplankton bloom. Satellite imagery indicates high mesoscale variability hypothesized that phytoplankton ingestion by N. flemingeri and N. plumchrus would vary in response to mesoscale

  5. New Efficient Sparse SpaceTime Algorithms for Superparameterization on Mesoscales

    E-Print Network [OSTI]

    Xing, Yulong

    New Efficient Sparse Space­Time Algorithms for Superparameterization on Mesoscales YULONG XING-scale and mesoscale processes provided by a cloud-resolving model (CRM) embedded in each column of a large-scale model for limited-area mesoscale ensemble forecasting. 1. Introduction Atmospheric processes of weather and climate

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

    E-Print Network [OSTI]

    Ju, Yiguang

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

  7. Segmentation of mesoscale ocean surface dynamics using satellite SST and SSH observations

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Segmentation of mesoscale ocean surface dynamics using satellite SST and SSH observations Pierre about ocean circulation, espe- cially mesoscale ocean dynamics which may involve strong spatio- temporal to which mesoscale ocean dynamics may be decomposed into a mixture of dynamical modes, characterized

  8. Mesoscale Simulation of Grain David Kinderlehrer, Jeehyun Lee, Irene Livshits and Shlomo Ta'asan

    E-Print Network [OSTI]

    Mesoscale Simulation of Grain Growth David Kinderlehrer, Jeehyun Lee, Irene Livshits and Shlomo Ta'asan WILEY-VCH Verlag Berlin GmbH September 4, 2003 #12;2 0.1 Introduction The mesoscale simulation of grain of the statistics it provides, we are led to the companion issue of coarse graining in mesoscale simulations. We

  9. The Importance of Mesoscale Circulations Generated by SubgridScale Landscape Heterogeneities in General Circulations Models

    E-Print Network [OSTI]

    Fridlind, Ann

    jcl92c.tex The Importance of Mesoscale Circulations Generated by Subgrid­Scale Landscape Oceanography, Cook Campus, Rutgers University, New Brunswick, NJ 08903, USA. #12; Abstract A mesoscale. These results emphasize the need to parameterize mesoscale processes induced by landscape discontinuities

  10. Mesoscale energetics and ows induced by sea-land and mountain-valley contrasts

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Mesoscale energetics and ¯ows induced by sea-land and mountain-valley contrasts S. Federico1 , G. A in determining the development of thermally forced mesoscale circula- tions (TFMCs) over a mountainous peninsula dynamics (climatology; mesoscale meteorology) 1 Introduction In the early hours of the morning the sun

  11. DETECTING AND TRACKING OF MESOSCALE OCEANIC FEATURES IN THE MIAMI ISOPYCNIC CIRCULATION OCEAN MODEL

    E-Print Network [OSTI]

    Tandon, Amit

    DETECTING AND TRACKING OF MESOSCALE OCEANIC FEATURES IN THE MIAMI ISOPYCNIC CIRCULATION OCEAN MODEL developed to automatically detect, locate and track mesoscale eddies spatially and temporally. Using an invaluable tool to assess mesoscale oceanic features. Key Words ­ Scientific Visualization, Eddy Detection

  12. Mesoscale transport properties induced by near critical resistive pressure-gradient-driven turbulence in toroidal geometry

    E-Print Network [OSTI]

    Martín-Solís, José Ramón

    Mesoscale transport properties induced by near critical resistive pressure diffusive equation for mesoscale tracer-particle transport. The indices of the fractional derivates a mesoscale regime. That is, for time scales above the fluctuation scales reaching to the trans- port scales

  13. Heat transport and weakening of atmospheric stability induced by mesoscale flows

    E-Print Network [OSTI]

    Pielke, Roger A.

    Heat transport and weakening of atmospheric stability induced by mesoscale flows G. A. Dalu boundary layer (CBL) is transported upward into the midtroposphere by mesoscale flows, and how the air, and diffusion, associated with the mesoscale flow, is more clearly shown when the forcing is periodic in time

  14. Draft Chapter from Mesoscale Dynamic Meteorology By Prof. Yu-lang Lin, North Carolina State University

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    1 Draft Chapter from Mesoscale Dynamic Meteorology By Prof. Yu-lang Lin, North Carolina State University Chapter 1 Overview 1.1 Introduction The so-called mesometeorology or mesoscale meteorology as mesoscale phenomena by others (e.g. Orlanski 1975; Thunis and Bornstein 1996). Therefore, a more precise

  15. MESOSCALE ANALYSIS OF A CAROLINA COASTAL FRONT SETHU RAMAN, NEERAJA C. REDDY and DEVDUTTA S. NIYOGI

    E-Print Network [OSTI]

    Niyogi, Dev

    MESOSCALE ANALYSIS OF A CAROLINA COASTAL FRONT SETHU RAMAN, NEERAJA C. REDDY and DEVDUTTA S. NIYOGI the shore. Key words: GALE, Coastal front, Atmospheric boundary layer, Gulf Stream, Mesoscale analysis turbulent heat fluxes. These strong gradients in heat fluxes enhance mesoscale circulation

  16. Mesoscale eddies in the northeastern Pacific tropical-subtropical transition zone: Statistical characterization from satellite altimetry

    E-Print Network [OSTI]

    Mesoscale eddies in the northeastern Pacific tropical-subtropical transition zone: Statistical February 2012; revised 24 August 2012; accepted 6 September 2012; published 24 October 2012. [1] Mesoscale cycle. Although mesoscale eddies in these areas have been previously reported, this study provides

  17. Mesoscale distribution of zooplankton biomass in the northeast Atlantic Ocean determined with an Optical Plankton Counter

    E-Print Network [OSTI]

    Mesoscale distribution of zooplankton biomass in the northeast Atlantic Ocean determined Available online 2 June 2009 Keywords: Zooplankton Biomass Size distribution Mesoscale eddies Optical plankton counter Pelagic environment Northeast Atlantic Ocean a b s t r a c t We examined the mesoscale

  18. Large-Scale Errors and Mesoscale Predictability in Pacific Northwest Snowstorms DALE R. DURRAN

    E-Print Network [OSTI]

    Large-Scale Errors and Mesoscale Predictability in Pacific Northwest Snowstorms DALE R. DURRAN The development of mesoscale numerical weather prediction (NWP) models over the last two decades has made- search communities. Nevertheless, the predictability of the mesoscale features captured in such forecasts

  19. Fast Explicit Operator Splitting Method for Convection-Diffusion Equations

    E-Print Network [OSTI]

    Kurganov, Alexander

    to the one- and two-dimensional systems of convection-diffusion equations which model the polymer flooding) processes in fluid mechanics, astrophysics, me- teorology, multiphase flow in oil reservoirs, polymer flow

  20. Identification of Robust Routes using Convective Weather Forcasts

    E-Print Network [OSTI]

    Michalek, Diana

    Convective weather is responsible for large delays and widespread disruptions in the U.S. National Airspace System (NAS), especially during summer months when travel demand is high. This has been the motivation for Air ...

  1. Identification of Robust Terminal-Area Routes in Convective Weather

    E-Print Network [OSTI]

    Balakrishnan, Hamsa

    Convective weather is responsible for large delays and widespread disruptions in the U.S. National Airspace System, especially during summer. Traffic flow management algorithms require reliable forecasts of route blockage ...

  2. Review of structure representation and reconstruction on mesoscale and microscale

    SciTech Connect (OSTI)

    Li, Dongsheng

    2014-05-01

    Structure representation and reconstruction on mesoscale and microscale is critical in material design, advanced manufacturing and multiscale modeling. Microstructure reconstruction has been applied in different areas of materials science and technology, structural materials, energy materials, geology, hydrology, etc. This review summarizes the microstructure descriptors and formulations used to represent and algorithms to reconstruct structures at microscale and mesoscale. In the stochastic methods using correlation function, different optimization approaches have been adapted for objective function minimization. A variety of reconstruction approaches are compared in efficiency and accuracy.

  3. Eddy heat fluxes at Drake Passage due to mesoscale motions 

    E-Print Network [OSTI]

    Rojas Recabal, Ricardo Luis

    1982-01-01

    EDDY HEAT FLUKES AT DRAKE PASSAGE DUE TO MESOSCALE MOTIONS A Thesis by RICARDO LUIS ROJAS RECABAL Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May... 1982 Major Subject: Oceanography EDDY HEAT FLUXES AT DRAKE PASSAGE DUE TO MESOSCALE NOTIONS A Thesis by RICARDO LUIS ROJAS RECABAL Approved as to style and content by: was )W-~ Member em er May 1982 ABSTRACT Eddy Heat Fluxes at Drake Passage...

  4. Use of a fictitious Marangoni number for natural convection simulation

    E-Print Network [OSTI]

    Arias, Francisco J.; Parks, Geoffrey T.

    2015-05-14

    - portance in many engineering and scientific applications such as energy transfer, boilers, nuclear reactor systems, energy storage devices, etc. In the design of such systems numerical simulation using computational fluid dynamics (CFD) and experimental... spacing of vertical, natural convection cooled, parallel plates. ASME J. Heat Transfer, 106 (1) (1984), pp. 116–123 [19] C.T. Tran, T.N. Dinh, Simulation of core melt pool formation in a reactor pressure vessel lower head using an effective convective...

  5. Screening properties of four mesoscale smoothed charge models, with application to dissipative particle dynamics

    E-Print Network [OSTI]

    Patrick B. Warren; Andrey Vlasov

    2014-02-25

    We extend our previous study [J. Chem. Phys. 138, 204907 (2013)] to quantify the screening properties of four mesoscale smoothed charge models used in dissipative particle dynamics. Using a combination of the hypernetted chain integral equation closure and the random phase approximation, we identify regions where the models exhibit a real-valued screening length, and the extent to which this agrees with the Debye length in the physical system. We find that the second moment of the smoothed charge distribution is a good predictor of this behaviour. We are thus able to recommend a consistent set of parameters for the models.

  6. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatist...

    E-Print Network [OSTI]

    Raftery, Adrian

    permission. Calibrated Probabilistic Mesoscale Weather Field Forecasting: The Geostatist... Yulia Gel; Adrian

  7. Laminar boundary layers in convective heat transport

    E-Print Network [OSTI]

    Christian Seis

    2012-12-12

    We study Rayleigh-Benard convection in the high-Rayleigh-number and high-Prandtl-number regime, i.e., we consider a fluid in a container that is exposed to strong heating of the bottom and cooling of the top plate in the absence of inertia effects. While the dynamics in the bulk are characterized by a chaotic convective heat flow, the boundary layers at the horizontal container plates are essentially conducting and thus the fluid is motionless. Consequently, the average temperature exhibits a linear profile in the boundary layers. In this article, we rigorously investigate the average temperature and oscillations in the boundary layer via local bounds on the temperature field. Moreover, we deduce that the temperature profile is indeed essentially linear close to the horizontal container plates. Our results are uniform in the system parameters (e.g. the Rayleigh number) up to logarithmic correction terms. An important tool in our analysis is a new Hardy-type estimate for the convecting velocity field, which can be used to control the fluid motion in the layer. The bounds on the temperature field are derived with the help of local maximal regularity estimates for convection-diffusion equations.

  8. The Phenix ultimate natural convection test

    SciTech Connect (OSTI)

    Gauthe, P.; Pialla, D.; Tenchine, D.; Vasile, A.; Rochwerger, D.

    2012-07-01

    The French sodium cooled fast reactor Phenix was shut down in 2009 after 35 years of operation. Before decommissioning, a final set of tests were performed by the CEA during 9 months. Several topics were involved such as thermal hydraulics, core physics and fuel behaviour. Among these ultimate experiments, two thermal hydraulic tests were performed: an asymmetrical test consisting in a trip of one secondary pump and a natural convection test in the primary circuit. Recognizing the unique opportunity offered by these Phenix ultimate tests, IAEA decided in 2007 to launch a Coordinated Research Project (CRP) devoted to benchmarking analyses with system codes on the Phenix natural convection test. One objective of the natural convection test in Phenix reactor is the assessment of the CATHARE system code for safety studies on future and advanced sodium cooled fast reactors. The aim of this paper is to describe this test, which was performed on June 22-23, 2009, and the associated benchmark specifications for the CRP work. The paper reminds briefly the Phenix reactor with the main physical parameters and the instrumentation used during the natural convection test. After that, the test scenario is described: - initial state at a power of 120 MWth, - test beginning resulting from a manual dry out of the two steam generators, - manual scram, - manual trip on the three primary pumps without back-up by pony motors, - setting and development of natural convection in the primary circuit, in a first phase without significant heat sink in the secondary circuits and in a second phase with significant heat sink in the secondary circuits, by opening the casing of steam generators to create an efficient heat sink, by air natural circulation in the steam generators casing. The benchmark case ends after this second phase, which corresponds to the experimental test duration of nearly 7 hours. The paper presents also the benchmark specifications data supplied by the CEA to all participants of this CRP in order to perform calculations (core, primary circuit, primary pumps, IHX, shutdown system, operating parameters, test scenario and real test conditions). Finally, main test results and analyses are presented including the evolution of the core and of the heat exchangers inlet and outlet temperatures, and some local temperature measurements. The natural convection has been easily set up in the pool type reactor Phenix with different boundary conditions at the secondary side, with or without heat sink. The data obtained during this unique test represent some very useful and precious results for the development of SFR in a wide range of thematic such as numerical methods dedicated to thermal-hydraulics safety analyses (system codes, CFD codes and coupling system and CFD codes) and instrumentation. (authors)

  9. Characterization of Caribbean Meso-Scale Eddies Jose M. Lopez

    E-Print Network [OSTI]

    Gilbes, Fernando

    Characterization of Caribbean Meso-Scale Eddies Jose M. Lopez Department of Marine Sciences, P will be subjected to 3-D spectrofluorometry and scanning spectrophotometry for CDOM characterization (J. Corredor, J. Morell). Current structure across fronts and eddies will be characterized by means of ship-lowered ADCP

  10. Wind resource assessment with a mesoscale non-hydrostatic model

    E-Print Network [OSTI]

    Boyer, Edmond

    Wind resource assessment with a mesoscale non- hydrostatic model Vincent Guénard, Center for Energy is developed for assessing the wind resource and its uncertainty. The work focuses on an existing wind farm mast measurements. The wind speed and turbulence fields are discussed. It is shown that the k

  11. Numerical Simulation in Applied Geophysics. From the Mesoscale to the

    E-Print Network [OSTI]

    Santos, Juan

    Seismic wave propagation is a common technique used in hydrocarbon exploration geophysics, mining's crust and induce attenuation, dispersion and anisotropy of the seismic waves observed at the macroscale process. Numerical Simulation in Applied Geophysics. From the Mesoscale to the Macroscale ­ p. #12

  12. LANSCE School on Neutron Scattering: Materials at the Mesoscale

    E-Print Network [OSTI]

    1 11th LANSCE School on Neutron Scattering: Materials at the Mesoscale Lujan Center Los Alamos. Please name the applicant for admission to the 11th LANSCE School on Neutron Scattering: Last, First LANSCE School on Neutron Scattering including: drive and motivation, ability to work with others

  13. Life Cycle of a Mesoscale Circular Gust Front Observed by a C-Band Doppler Radar in West Africa

    E-Print Network [OSTI]

    Lothon, Marie

    On 10 July 2006, during the Special Observation Period (SOP) of the African Monsoon Multidisciplinary Analysis (AMMA) campaign, a small convective system initiated over Niamey and propagated westward in the vicinity of ...

  14. Coastal mesoscale changes on Matagorda Island 

    E-Print Network [OSTI]

    Lariscy, Kevin William

    2001-01-01

    and the dune systems. The data indicates that Matagorda Island is currently experiencing a net aggradational phase, as part of a geomorphic system undergoing dynamic equilibrium....

  15. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1985-01-01

    Natural convection can provide adequate heat distribution in many situtations that arise in buildings. This is appropriate, for example, in passive solar buildings where some rooms tend to be more strongly solar heated than others or to reduce the number of heating units required in a building. Natural airflow and heat transport through doorways and other internal building apertures is predictable and can be accounted for in the design. The nature of natural convection is described, and a design chart is presented appropriate to a simple, single-doorway situation. Natural convective loops that can occur in buildings are described and a few design guidelines are presented.

  16. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.; Yamaguchi, K.

    1983-01-01

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

  17. Penetrative turbulence associated with mesoscale surface heat flux variations

    E-Print Network [OSTI]

    Alam, Jahrul M

    2015-01-01

    This article investigates penetrative turbulence in the atmospheric boundary layer. Using a large eddy simulation approach, we study characteristics of the mixed layer with respect to surface heat flux variations in the range from 231.48 W/m$^2$ to 925.92 W/m$^2$, and observe that the surface heterogeneity on a spatial scale of $20$ km leads to downscale turbulent kinetic energy cascade. Coherent fluctuations of mesoscale horizontal wind is observed at 100m above the ground. Such a surface induced temporal oscillations in the horizontal wind suggest a rapid jump in mesocale wind forecasts, which is difficult to parameterize using traditional one-dimensional ensemble-mean models. Although the present work is idealized at a typical scale (20km) of surface heterogeneity, the results help develop effective subgrid scale parameterization schemes for classical weather forecasting mesoscale models.

  18. Quantum fluctuations and saturable absorption in mesoscale lasers

    SciTech Connect (OSTI)

    Roy-Choudhury, Kaushik [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States); Levi, A. F. J. [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States); Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089-2533 (United States)

    2011-04-15

    We present a quantum-mechanical treatment of fluctuations and saturable absorption in mesoscale lasers. The time evolution of the density matrix is obtained from numerical integration and field-field and intensity-intensity correlations are calculated to obtain steady-state linewidth and photon statistics. Inclusion of a saturable absorber in the otherwise homogeneous medium is shown to suppress lasing, increase fluctuations, and enhance spontaneous emission near threshold.

  19. Mesoscale Modeling of LX-17 Under Isentropic Compression

    SciTech Connect (OSTI)

    Springer, H K; Willey, T M; Friedman, G; Fried, L E; Vandersall, K S; Baer, M R

    2010-03-06

    Mesoscale simulations of LX-17 incorporating different equilibrium mixture models were used to investigate the unreacted equation-of-state (UEOS) of TATB. Candidate TATB UEOS were calculated using the equilibrium mixture models and benchmarked with mesoscale simulations of isentropic compression experiments (ICE). X-ray computed tomography (XRCT) data provided the basis for initializing the simulations with realistic microstructural details. Three equilibrium mixture models were used in this study. The single constituent with conservation equations (SCCE) model was based on a mass-fraction weighted specific volume and the conservation of mass, momentum, and energy. The single constituent equation-of-state (SCEOS) model was based on a mass-fraction weighted specific volume and the equation-of-state of the constituents. The kinetic energy averaging (KEA) model was based on a mass-fraction weighted particle velocity mixture rule and the conservation equations. The SCEOS model yielded the stiffest TATB EOS (0.121{micro} + 0.4958{micro}{sup 2} + 2.0473{micro}{sup 3}) and, when incorporated in mesoscale simulations of the ICE, demonstrated the best agreement with VISAR velocity data for both specimen thicknesses. The SCCE model yielded a relatively more compliant EOS (0.1999{micro}-0.6967{micro}{sup 2} + 4.9546{micro}{sup 3}) and the KEA model yielded the most compliant EOS (0.1999{micro}-0.6967{micro}{sup 2}+4.9546{micro}{sup 3}) of all the equilibrium mixture models. Mesoscale simulations with the lower density TATB adiabatic EOS data demonstrated the least agreement with VISAR velocity data.

  20. Mesoscale modeling of metal-loaded high explosives

    SciTech Connect (OSTI)

    Bdzil, John Bohdan [Los Alamos National Laboratory; Lieberthal, Brandon [UNIV OF ILLINOIS; Srewart, Donald S [UNIV OF ILLINOIS

    2010-01-01

    We describe a 3D approach to modeling multi-phase blast explosive, which is primarily condensed explosive by volume with inert embedded particles. These embedded particles are uniform in size and placed on the array of a regular lattice. The asymptotic theory of detonation shock dynamics governs the detonation shock propagation in the explosive. Mesoscale hydrodynamic simulations are used to show how the particles are compressed, deformed, and accelerated by the high-speed detonation products flow.

  1. Heat distribution by natural convection

    SciTech Connect (OSTI)

    Balcomb, J.D.

    1985-01-01

    Natural convection can provide adequate heat distribution in many situations that arise in buildings. This is appropriate, for example, in passive solar buildings where some rooms tend to be more strongly solar heated than others. Natural convection can also be used to reduce the number of auxiliary heating units required in a building. Natural airflow and heat transport through doorways and other internal building apertures are predictable and can be accounted for in the design. The nature of natural convection is described, and a design chart is presented appropriate to a simple, single-doorway situation. Experimental results are summarized based on the monitoring of 15 passive solar buildings which employ a wide variety of geometrical configurations including natural convective loops.

  2. Determining Greenland Ice Sheet sensitivity to regional climate change: one-way coupling of a 3-D thermo-mechanical ice sheet model with a mesoscale climate model

    E-Print Network [OSTI]

    Schlegel, Nicole-Jeanne

    2011-01-01

    ice sheet model with a mesoscale climate model By Nicole-ice sheet model with a mesoscale climate model Copyrightice sheet model with a mesoscale climate model by Nicole-

  3. Convective heat flow probe

    DOE Patents [OSTI]

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

    1984-01-09

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

  4. Laminar boundary layers in convective heat transport

    E-Print Network [OSTI]

    Seis, Christian

    2012-01-01

    We study Rayleigh-Benard convection in the high-Rayleigh-number and high-Prandtl-number regime, i.e., we consider a fluid in a container that is exposed to strong heating of the bottom and cooling of the top plate in the absence of inertia effects. While the dynamics in the bulk are characterized by a chaotic convective heat flow, the boundary layers at the horizontal container plates are essentially conducting and thus the fluid is motionless. Consequently, the average temperature exhibits a linear profile in the boundary layers. In this article, we rigorously investigate the average temperature and oscillations in the boundary layer via local bounds on the temperature field. Moreover, we deduce that the temperature profile is indeed essentially linear close to the horizontal container plates. Our results are uniform in the system parameters (e.g. the Rayleigh number) up to logarithmic correction terms. An important tool in our analysis is a new Hardy-type estimate for the convecting velocity field, which ca...

  5. Silicon Micromachined Dimensional Calibration Artifact for Mesoscale...

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

    and fuel injector assemblies in the automotive industry, and chip-scale packaging and MEMS (Micro-Electro-Mechanical-Systems) assemblies in the electronics industry. Not only do...

  6. Natural convection heat transfer within horizontal spent nuclear fuel assemblies

    SciTech Connect (OSTI)

    Canaan, R.E.

    1995-12-01

    Natural convection heat transfer is experimentally investigated in an enclosed horizontal rod bundle, which characterizes a spent nuclear fuel assembly during dry storage and/or transport conditions. The basic test section consists of a square array of sixty-four stainless steel tubular heaters enclosed within a water-cooled rectangular copper heat exchanger. The heaters are supplied with a uniform power generation per unit length while the surrounding enclosure is maintained at a uniform temperature. The test section resides within a vacuum/pressure chamber in order to subject the assembly to a range of pressure statepoints and various backfill gases. The objective of this experimental study is to obtain convection correlations which can be used in order to easily incorporate convective effects into analytical models of horizontal spent fuel systems, and also to investigate the physical nature of natural convection in enclosed horizontal rod bundles in general. The resulting data consist of: (1) measured temperatures within the assembly as a function of power, pressure, and backfill gas; (2) the relative radiative contribution for the range of observed temperatures; (3) correlations of convective Nusselt number and Rayleigh number for the rod bundle as a whole; and (4) correlations of convective Nusselt number as a function of Rayleigh number for individual rods within the array.

  7. New ALS Technique Gives Nanoscale Views of Complex Systems

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

    Nanoscale Views of Complex Systems Print Studying and identifying molecules at the mesoscale has always been challenging-even the best microscopes and spectrometers have...

  8. New ALS Technique Gives Nanoscale Views of Complex Systems

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

    Systems Print Wednesday, 28 May 2014 00:00 Studying and identifying molecules at the mesoscale has always been challenging-even the best microscopes and spectrometers have...

  9. Inferring the mesoscale structure of layered, edge-valued and time-varying networks

    E-Print Network [OSTI]

    Peixoto, Tiago P

    2015-01-01

    Many network systems are composed of interdependent but distinct types of interactions, which cannot be fully understood in isolation. These different types of interactions are often represented as layers, attributes on the edges or as a time-dependence of the network structure. Although they are crucial for a more comprehensive scientific understanding, these representations offer substantial challenges. Namely, it is an open problem how to precisely characterize the large or mesoscale structure of network systems in relation to these additional aspects. Furthermore, the direct incorporation of these features invariably increases the effective dimension of the network description, and hence aggravates the problem of overfitting, i.e. the use of overly-complex characterizations that mistake purely random fluctuations for actual structure. In this work, we propose a robust and principled method to tackle these problems, by constructing generative models of modular network structure, incorporating layered, attr...

  10. FREE CONVECTIVE LAMINAR FLOW WITHIN THE TROMBE WALL CHANNEL

    E-Print Network [OSTI]

    Akbari, H.

    2011-01-01

    Foreign FREE CONVECTIVE LAMINAR FLOW WITHIN THE TROMBE WALLEnergy. -i- FREE CONVECTIVE LAMINAR FLOW WITHIN THE TROMBEABSTRACT Free convective laminar heat transfer between the

  11. The Retrieval of Ice Water Content from Radar Reflectivity Factor and Temperature and Its Use in Evaluating a Mesoscale Model

    E-Print Network [OSTI]

    Hogan, Robin

    in Evaluating a Mesoscale Model ROBIN J. HOGAN, MARION P. MITTERMAIER,* AND ANTHONY J. ILLINGWORTH Department-GHz radar with the values held in the Met Office mesoscale forecast model, for eight precipitating

  12. TextureCam: A Smart Camera for Microscale, Mesoscale, and Deep Space Applications. David R. Thomp-, William Abbey2

    E-Print Network [OSTI]

    Wagstaff, Kiri L.

    TextureCam: A Smart Camera for Microscale, Mesoscale, and Deep Space Applications. David R. Thomp variable illumination. #12;Mesoscale Geologic Surface Classification: Re- cent tests on images collected

  13. NATURE |VOL 407 |12 OCTOBER 2000 |www.nature.com 695 A mesoscale phytoplankton bloom in the

    E-Print Network [OSTI]

    Kudela, Raphael M.

    NATURE |VOL 407 |12 OCTOBER 2000 |www.nature.com 695 articles A mesoscale phytoplankton bloom report the results of a mesoscale iron fertilization experiment in the polar Southern Ocean, where

  14. Environment and the Lifetime of Tropical Deep Convection in a Cloud-Permitting Regional Model Simulation

    SciTech Connect (OSTI)

    Hagos, Samson M.; Feng, Zhe; McFarlane, Sally A.; Leung, Lai-Yung R.

    2013-08-01

    By applying a cloud tracking algorithm to tropical convective systems simulated by a regional high resolution model, the study documents environmental conditions before and after convective systems are initiated over ocean and land by following them during their lifetime. The comparative roles of various environmental fields in affecting the lifetime of convection are also quantified. The statistics of lifetime, maximum area, propagation speed and direction of the simulated deep convection agrees well with geostationary satellite observations. Over ocean, convective systems enhance surface fluxes through the associated wind gusts as well as cooling and drying of the boundary layer. A significant relationship is found between the mean surface fluxes during their lifetime and the longevity of the systems which in turn is related to the initial intensity of the moist updraft and to a lesser extent upper level shear. Over land, on the other hand, convective activity suppresses surface fluxes through cloud cover and the lifetime of convection is related to the upper level shear during their lifetime and strength of the heat fluxes several hours before the initiation of convection. For systems of equal lifetime, those over land are significantly more intense than those over ocean especially during early stages of their lifetime.

  15. Deriving effective mesoscale potentials from atomistic simulations

    E-Print Network [OSTI]

    Dirk Reith; Mathias Puetz; Florian Mueller-Plathe

    2002-11-20

    We demonstrate how an iterative method for potential inversion from distribution functions developed for simple liquid systems can be generalized to polymer systems. It uses the differences in the potentials of mean force between the distribution functions generated from a guessed potential and the true (simulated) distribution functions to improve the effective potential successively. The optimization algorithm is very powerful: convergence is reached for every trial function in few iterations. As an extensive test case we coarse-grained an atomistic all-atom model of poly (isoprene) (PI) using a 13:1 reduction of the degrees of freedom. This procedure was performed for PI solutions as well as for a PI melt. Comparisons of the obtained force fields are drawn. They prove that it is not possible to use a single force field for different concentration regimes.

  16. Generation of strong mesoscale eddies by weak ocean gyres by Michael A. Spall1

    E-Print Network [OSTI]

    Generation of strong mesoscale eddies by weak ocean gyres by Michael A. Spall1 ABSTRACT The generation of strong mesoscale variability through instability of the large-scale circulation in the interior of oceanic gyres is addressed. While previous studies have shown that eddies generated from weakly sheared

  17. Development of fine-resolution analyses and expanded large-scale...

    Office of Scientific and Technical Information (OSTI)

    realistically reproduces the intensity, structure, and time evolution of clouds and precipitation associated with a mesoscale convective system. Evaluations also show that the...

  18. Physically consistent simulation of mesoscale chemical kinetics: The non-negative FIS-{alpha} method

    SciTech Connect (OSTI)

    Dana, Saswati, E-mail: saswatid@rishi.serc.iisc.ernet.in [Supercomputer Education and Research Centre, Indian Institute of Science, Bangalore 560012 (India); Raha, Soumyendu, E-mail: raha@serc.iisc.ernet.in [Supercomputer Education and Research Centre, Indian Institute of Science, Bangalore 560012 (India)

    2011-10-01

    Biochemical pathways involving chemical kinetics in medium concentrations (i.e., at mesoscale) of the reacting molecules can be approximated as chemical Langevin equations (CLE) systems. We address the physically consistent non-negative simulation of the CLE sample paths as well as the issue of non-Lipschitz diffusion coefficients when a species approaches depletion and any stiffness due to faster reactions. The non-negative Fully Implicit Stochastic {alpha} (FIS {alpha}) method in which stopped reaction channels due to depleted reactants are deleted until a reactant concentration rises again, for non-negativity preservation and in which a positive definite Jacobian is maintained to deal with possible stiffness, is proposed and analysed. The method is illustrated with the computation of active Protein Kinase C response in the Protein Kinase C pathway.

  19. Spatial Intermittency of Surface Layer Wind Fluctuations at Mesoscale Range Rachel Baile* and Jean-Francois Muzy

    E-Print Network [OSTI]

    Boyer, Edmond

    Spatial Intermittency of Surface Layer Wind Fluctuations at Mesoscale Range Rachel Bai¨le* and Jean and to confirm an intermittent nature of mesoscale fluctuations similar to the one observed in fully developed involving a wide range of spatiotemporal scales. The modeling of wind speed behavior in the mesoscale range

  20. Anatomy and evolution of a cyclonic mesoscale eddy observed in the northeastern Pacific tropical-subtropical transition zone

    E-Print Network [OSTI]

    Anatomy and evolution of a cyclonic mesoscale eddy observed in the northeastern Pacific tropical and evolution of a cyclonic mesoscale eddy observed in the northeastern Pacific tropical-subtropical transition zone, J. Geophys. Res. Oceans, 118, doi:10.1002/ 2013JC009339. 1. Introduction [2] Mesoscale eddy

  1. FeCycle: Attempting an iron biogeochemical budget from a mesoscale SF6 tracer experiment in unperturbed low iron waters

    E-Print Network [OSTI]

    Wilhelm, Steven W.

    FeCycle: Attempting an iron biogeochemical budget from a mesoscale SF6 tracer experiment to ocean physics. In summer 2003 we conducted FeCycle, a 10-day mesoscale tracer release in HNLC waters SE biogeochemical budget from a mesoscale SF6 tracer experiment in unperturbed low iron waters, Global Biogeochem

  2. Development and Evaluation of a Coupled Photosynthesis-Based Gas Exchange Evapotranspiration Model (GEM) for Mesoscale Weather Forecasting Applications

    E-Print Network [OSTI]

    Niyogi, Dev

    (GEM) for Mesoscale Weather Forecasting Applications DEV NIYOGI Department of Agronomy, and Department form 13 May 2008) ABSTRACT Current land surface schemes used for mesoscale weather forecast models use model (GEM) as a land surface scheme for mesoscale weather forecasting model applications. The GEM

  3. IEEE TRANSACTIONS ON ROBOTICS, VOL. 25, NO. 5, OCTOBER 2009 1047 A New Mechanism for Mesoscale Legged

    E-Print Network [OSTI]

    IEEE TRANSACTIONS ON ROBOTICS, VOL. 25, NO. 5, OCTOBER 2009 1047 A New Mechanism for Mesoscale for a novel mechanism for robotic legged locomotion at the mesoscale (from hundreds of microns to tens mesoscale locomotion tasks, in- cluding endoscopic capsule robot locomotion in the gastrointestinal tract

  4. Effect of mesoscale topography over the Tibetan Plateau on summer precipitation in China: A regional model study

    E-Print Network [OSTI]

    Wang, Yuqing

    Effect of mesoscale topography over the Tibetan Plateau on summer precipitation in China 2008; accepted 27 August 2008; published 8 October 2008. [1] The effect of mesoscale topography over and topography. In the sensitivity simulation, the mesoscale feature in topography over the TP was smoothed out

  5. Characterization of Mesoscale Coiled-Coil Peptide-Porphyrin Brian J. Pepe-Mooney, Bashkim Kokona, and Robert Fairman*

    E-Print Network [OSTI]

    Fairman, Robert

    Characterization of Mesoscale Coiled-Coil Peptide-Porphyrin Complexes Brian J. Pepe-Mooney, Bashkim-assemble to form mesoscale filaments and serve as a scaffold for porphyrin interaction. In our earlier work mesoscale fibrils were formed, taking advantage of the types of porphyrin interactions that are present

  6. Nature of the Mesoscale Boundary Layer Height and Water Vapor Variability Observed 14 June 2002 during the IHOP_2002 Campaign

    E-Print Network [OSTI]

    Nature of the Mesoscale Boundary Layer Height and Water Vapor Variability Observed 14 June 2002, Boulder, Colorado (Manuscript received 4 September 2007, in final form 23 June 2008) ABSTRACT Mesoscale at the mesoscale, with the spatial pattern and the magnitude of the variability changing from day to day. On 14

  7. MESOSCALE VARIABILITIES IN SEA SURFACE CURRENT FIELDS DERIVED THROUGH MULTI-SENSOR TRACKING OF SEA SURFACE FILMS

    E-Print Network [OSTI]

    Hamburg,.Universität

    MESOSCALE VARIABILITIES IN SEA SURFACE CURRENT FIELDS DERIVED THROUGH MULTI-SENSOR TRACKING OF SEA have already shown that it is possible to derive mesoscale sea surface current fields by tracking of the `global' currents. 1. INTRODUCTION The investigation of mesoscale turbulent sea surface currents

  8. 978-1-4244-5489-1/10/ $26.00 c 2010 IEEE Understanding Topological Mesoscale Features

    E-Print Network [OSTI]

    Moon, Sue B.

    978-1-4244-5489-1/10/ $26.00 c 2010 IEEE Understanding Topological Mesoscale Features in Community and match them against known roles for evaluation. We apply topological mesoscale information to compare two characteristics, the communities unveil the mesoscale structure of the network and provide insight

  9. Multiscale models for synoptic-mesoscale interactions in the ocean1 , K. Shafer Smith, Andrew J. Majda2

    E-Print Network [OSTI]

    Majda, Andrew J.

    Multiscale models for synoptic-mesoscale interactions in the ocean1 Ian Grooms , K. Shafer Smith of the midlatitude oceanic synoptic scale -- where coherent features such as jets and rings form -- and the mesoscale, defined by the internal deformation scale. The synoptic scale and mesoscale overlap at low and mid

  10. Mesoscale Eddy Energy Locality in an Idealized Ocean Model IAN GROOMS, LOUIS-PHILIPPE NADEAU, AND K. SHAFER SMITH

    E-Print Network [OSTI]

    Smith, K. Shafer

    Mesoscale Eddy Energy Locality in an Idealized Ocean Model IAN GROOMS, LOUIS-PHILIPPE NADEAU, AND K investigates the energy budget of mesoscale eddies in wind-driven two-layer quasigeostrophic simulations of eddy energy are ``nonlocal.'' Many mesoscale parameterizations assume that statistics of the unresolved

  11. Isolating the role of mesoscale eddies in mixing of a passive tracer in an eddy resolving model

    E-Print Network [OSTI]

    Miami, University of

    Isolating the role of mesoscale eddies in mixing of a passive tracer in an eddy resolving model February 2008; published 16 May 2008. [1] This study examines the role of mesoscale eddies in distribution was replaced by a down-gradient diffusive parameterization. Our results demonstrate that advection by mesoscale

  12. Modeling mesoscale eddies V.M. Canuto a,b,*, M.S. Dubovikov a,c

    E-Print Network [OSTI]

    Modeling mesoscale eddies V.M. Canuto a,b,*, M.S. Dubovikov a,c a Goddard Institute for Spaces November 2003 Available online 6 December 2003 Abstract Mesoscale eddies are not resolved in coarse, no generally accepted model exists for the former; in the latter case, mesoscales are modeled with a bolus

  13. THE USE OF SPATIAL CONSTRAINTS IN THE DERIVATION OF MESOSCALE SEA SURFACE CURRENT FIELDS FROM MULTI-SENSOR SATELLITE DATA

    E-Print Network [OSTI]

    Hamburg,.Universität

    THE USE OF SPATIAL CONSTRAINTS IN THE DERIVATION OF MESOSCALE SEA SURFACE CURRENT FIELDS FROM MULTI images are used for the computation of mesoscale surface currents in the Northern and Southern Baltic for the derivation of mesoscale sea surface currents using multi-sensor / multi-channel satellite images by means

  14. Proceedings in Applied Mathematics and Mechanics, 31 October 2007 Parametrization for Mesoscale Ocean Transport through Random Flow

    E-Print Network [OSTI]

    Kramer, Peter

    Proceedings in Applied Mathematics and Mechanics, 31 October 2007 Parametrization for Mesoscale a mathematical approach based on homogenization theory toward representing the effects of mesoscale coherent in parameterizing the transport effects of sub-grid scale flow structures appearing in mesoscale oceanic turbulence

  15. An implicit finite-element model for 3D non-hydrostatic mesoscale ocean M.A. Maidana1

    E-Print Network [OSTI]

    Politècnica de Catalunya, Universitat

    An implicit finite-element model for 3D non-hydrostatic mesoscale ocean flows M.A. Maidana1 , J-dimensional, non-hydrostatic mesoscale ocean flows. The model considered here incorporates surface wind stress and the idea of using unstructured grids for modelling mesoscale ocean dynamics sounds very attractive given

  16. Mesoscale variability in time series data: Satellite-based estimates for the U.S. JGOFS Bermuda Atlantic

    E-Print Network [OSTI]

    Mesoscale variability in time series data: Satellite-based estimates for the U.S. JGOFS Bermuda TOPEX/Poseidon­ERS-1/2) are used to characterize, statistically, the mesoscale variability about the U to better understand the contribution of mesoscale eddies to the time series record and the model- data

  17. Analytical Rescaling of Polymer Dynamics from Mesoscale Simulations

    E-Print Network [OSTI]

    I. Y. Lyubimov; J. McCarty; A. Clark; M. G. Guenza

    2011-03-10

    We present a theoretical approach to scale the artificially fast dynamics of simulated coarse-grained polymer liquids down to its realistic value. As coarse-graining affects entropy and dissipation, two factors enter the rescaling: inclusion of intramolecular vibrational degrees of freedom, and rescaling of the friction coefficient. Because our approach is analytical, it is general and transferable. Translational and rotational diffusion of unentangled and entangled polyethylene melts, predicted from mesoscale simulations of coarse-grained polymer melts using our rescaling procedure, are in quantitative agreement with united atom simulations and with experiments.

  18. Mesoscale simulations of polymer dynamics in microchannel flows

    E-Print Network [OSTI]

    L. Cannavacciuolo; R. G. Winkler; G. Gompper

    2007-09-24

    The non-equilibrium structural and dynamical properties of flexible polymers confined in a square microchannel and exposed to a Poiseuille flow are investigated by mesoscale simulations. The chain length and the flow strength are systematically varied. Two transport regimes are identified, corresponding to weak and strong confinement. For strong confinement, the transport properties are independent of polymer length. The analysis of the long-time tumbling dynamics of short polymers yields non-periodic motion with a sublinear dependence on the flow strength. We find distinct differences for conformational as well as dynamical properties from results obtained for simple shear flow.

  19. Customizing mesoscale self-assembly with 3D printing

    E-Print Network [OSTI]

    M. Poty; G. Lumay; N. Vandewalle

    2013-10-17

    Self-assembly due to capillary forces is a common method for generating 2D mesoscale structures from identical floating particles at the liquid-air interface. Designing building blocks to obtain a desired mesoscopic structure is a scientific challenge. We show herein that it is possible to shape the particles with a low cost 3D printer, for composing specific mesoscopic structures. Our method is based on the creation of capillary multipoles inducing either attractive or repulsive forces. Since capillary interactions can be downscaled, our method opens new ways to low cost microfabrication.

  20. The convective desalination of sea ice

    E-Print Network [OSTI]

    Rees Jones, David

    2014-07-01

    in the interstices of an ice matrix. My focus is on one of the processes by which the salt content of sea ice decreases, namely convective desalination, which is also often called gravity drainage by geophysicists. Modelling convective desalination requires...

  1. NATURAL CONVECTION IN ROOM GEOMETRIES

    SciTech Connect (OSTI)

    Gadgil, A.; Bauman, Fred; Kammerud, R.; Ruberg, K.

    1980-06-01

    Computer programs have been developed to numerically simulate natural convection in room geometries in two and three dimensions. The programs have been validated using published data from the literature, results from a full-scale experiment performed at Massachusetts Institute of Technology, and results from a small-scale experiment reported here. One of the computer programs has been used to study the influence of natural convection on the thermal performance of a single thermal zone in a direct-gain passive solar building. The results indicate that the building heating loads calculated by standard building energy analysis methods may be in error by as much as 50% as a result of their use of common assumptions regarding the convection processes which occur in an enclosure. It is also found that the convective heat transfer coefficients between the air and the enclosure surfaces can be substantially different from the values assumed in the standard building energy analysis methods, and can exhibit significant variations across a given surface.

  2. A mesoscale analysis of the Rayleigh-Plateau instability.

    SciTech Connect (OSTI)

    Pao, Wenxiao (BU); Soteriou, Marios (UTRC); Li, Xiaoyi (UTRC); Karniadakis, George (BU); Arienti, Marco

    2010-11-01

    Capillary pinch-off results carried out with the Many-Body Dissipative Particle Dynamics (MDPD) method are compared with the two-phase continuum discretization of hydrodynamics. The MDPD method provides a mesoscale description of the liquid-gas interface -- molecules can be thought of as grouped in particles with modeled Brownian and dissipative effects. No liquid-gas interface is explicitly defined; surface properties, such as surface tension, result from the MDPD interaction parameters. In side-to-side comparisons, the behavior of the MDPD liquid is demonstrated to replicate the macroscale behavior (thin interface assumption) calculated by the Combined Level Set-Volume of Fluid (CLSVOF) method. For instance, in both the continuum and mesoscale discretizations the most unstable wavelength perturbation leads to pinch-off, whereas a smaller wavelength-to-diameter ratio, as expected, does not. The behavior of the virial pressure in MDPD will be discussed in relation to the hydrodynamic capillary pressure that results from the thin interface assumption.

  3. Dances and Balls: Fancy Dress Ball - 1 

    E-Print Network [OSTI]

    Unknown

    2006-01-01

    Two mesoscale convective systems (MCSs) passed over the Houston Lightning Detection and Ranging (LDAR) network on 31 October 2005 and 21 April 2006. As the MCSs traverse the LDAR network, the systems slowly mature with a weakening convective line...

  4. Mesoscale solubilization and critical phenomena in binary and quasi binary solutions of hydrotropes

    E-Print Network [OSTI]

    Andreas E. Robertson; Dung H. Phan; Joseph E. Macaluso; Vladimir N. Kuryakov; Elena V. Jouravleva; Christopher E. Bertrand; Igor K. Yudin; Mikhail A. Anisimov

    2015-03-24

    Hydrotropes are substances consisting of amphiphilic molecules that are too small to self assemble in equilibrium structures in aqueous solutions, but can form dynamic molecular clusters H bonded with water molecules. Some hydrotropes, such as low molecular weight alcohols and amines, can solubilize hydrophobic compounds in aqueous solutions at a mesoscopic scale, around 100 nm, with formation of long lived mesoscale droplets. In this work, we report on the studies of near critical and phase behavior of binary, 2,6-lutidine - H2O, and quasibinary, 2,6-lutidine - H2O - D2O, and tert-butanol - 2-butanol - H2O solutions in the presence of a solubilized hydrophobic impurity, cyclohexane. In additional to visual observation of fluid phase equilibria, two experimental techniques were used - light scattering and small - angle neutron scattering. It was found that the increase of the tert-butanol to 2-butanol ratio affects the liquid - liquid equilibria in the quasi-binary system at ambient pressure in the same way as the increase of pressure modifies the phase behavior of binary 2-butanol - H2O solutions. The correlation length of critical fluctuations near the liquid-liquid separation and the size of mesoscale droplets of solubilized cyclohexane were obtained by dynamic light scattering and by small - angle neutron scattering. It is shown that the effect of the presence of small amounts of cyclohexane on the near - critical phase behavior is twofold - the transition temperature changes towards increasing the two-phase domain, and long-lived mesoscopic inhomogeneities emerge in the macroscopically homogeneous domain. These homogeneities remain unchanged upon approach to the critical point of macroscopic phase separation and do not alter the universal nature of criticality. However, a larger amount of cyclohexane generates additional liquid-liquid phase separation at lower temperatures.

  5. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    N/m 2 per 10000km) against crosswind SST gradients ( ? C peroverlaid with contours crosswind SST gradients ( ? C perpositive (negative) crosswind SST gradients at 0.4 ? C per

  6. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    a shifted maximum wind stress offshore when compare to Fig.strengthening winds while extending offshore. A seasonalthe shift of wind stress peak offshore (Fig. 3.30) changes

  7. Mesoscale coupled ocean-atmosphere feedbacks in boundary current systems

    E-Print Network [OSTI]

    Putrasahan, Dian Ariyani

    2012-01-01

    to about 600km offshore, beyond which wind stress curla shifted maximum wind stress offshore when compare to Fig.strengthening winds while extending offshore. A seasonal

  8. ARM - Midlatitude Continental Convective Clouds (comstock-hvps)

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

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

    2012-01-06

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

  9. ARM - Midlatitude Continental Convective Clouds (comstock-hvps)

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

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

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

  10. Air-sea interaction at contrasting sites in the Eastern Tropical Pacific : mesoscale variability and atmospheric convection at 10°N

    E-Print Network [OSTI]

    Farrar, J. Thomas (John Thomas), 1976-

    2007-01-01

    The role of ocean dynamics in driving air-sea interaction is examined at two contrasting sites on 125°W in the eastern tropical Pacific Ocean using data from the Pan American Climate Study (PACS) field program. Analysis ...

  11. Mesoscale Benchmark Demonstration Problem 1: Mesoscale Simulations of Intra-granular Fission Gas Bubbles in UO2 under Post-irradiation Thermal Annealing

    SciTech Connect (OSTI)

    Li, Yulan; Hu, Shenyang Y.; Montgomery, Robert; Gao, Fei; Sun, Xin; Tonks, Michael; Biner, Bullent; Millet, Paul; Tikare, Veena; Radhakrishnan, Balasubramaniam; Andersson , David

    2012-04-11

    A study was conducted to evaluate the capabilities of different numerical methods used to represent microstructure behavior at the mesoscale for irradiated material using an idealized benchmark problem. The purpose of the mesoscale benchmark problem was to provide a common basis to assess several mesoscale methods with the objective of identifying the strengths and areas of improvement in the predictive modeling of microstructure evolution. In this work, mesoscale models (phase-field, Potts, and kinetic Monte Carlo) developed by PNNL, INL, SNL, and ORNL were used to calculate the evolution kinetics of intra-granular fission gas bubbles in UO2 fuel under post-irradiation thermal annealing conditions. The benchmark problem was constructed to include important microstructural evolution mechanisms on the kinetics of intra-granular fission gas bubble behavior such as the atomic diffusion of Xe atoms, U vacancies, and O vacancies, the effect of vacancy capture and emission from defects, and the elastic interaction of non-equilibrium gas bubbles. An idealized set of assumptions was imposed on the benchmark problem to simplify the mechanisms considered. The capability and numerical efficiency of different models are compared against selected experimental and simulation results. These comparisons find that the phase-field methods, by the nature of the free energy formulation, are able to represent a larger subset of the mechanisms influencing the intra-granular bubble growth and coarsening mechanisms in the idealized benchmark problem as compared to the Potts and kinetic Monte Carlo methods. It is recognized that the mesoscale benchmark problem as formulated does not specifically highlight the strengths of the discrete particle modeling used in the Potts and kinetic Monte Carlo methods. Future efforts are recommended to construct increasingly more complex mesoscale benchmark problems to further verify and validate the predictive capabilities of the mesoscale modeling methods used in this study.

  12. An analytical coarse-graining method which preserves the free energy, structural correlations, and thermodynamic state of polymer melts from the atomistic to the mesoscale

    SciTech Connect (OSTI)

    McCarty, J.; Clark, A. J.; Copperman, J.; Guenza, M. G.

    2014-05-28

    Structural and thermodynamic consistency of coarse-graining models across multiple length scales is essential for the predictive role of multi-scale modeling and molecular dynamic simulations that use mesoscale descriptions. Our approach is a coarse-grained model based on integral equation theory, which can represent polymer chains at variable levels of chemical details. The model is analytical and depends on molecular and thermodynamic parameters of the system under study, as well as on the direct correlation function in the k ? 0 limit, c{sub 0}. A numerical solution to the PRISM integral equations is used to determine c{sub 0}, by adjusting the value of the effective hard sphere diameter, d{sub HS}, to agree with the predicted equation of state. This single quantity parameterizes the coarse-grained potential, which is used to perform mesoscale simulations that are directly compared with atomistic-level simulations of the same system. We test our coarse-graining formalism by comparing structural correlations, isothermal compressibility, equation of state, Helmholtz and Gibbs free energies, and potential energy and entropy using both united atom and coarse-grained descriptions. We find quantitative agreement between the analytical formalism for the thermodynamic properties, and the results of Molecular Dynamics simulations, independent of the chosen level of representation. In the mesoscale description, the potential energy of the soft-particle interaction becomes a free energy in the coarse-grained coordinates which preserves the excess free energy from an ideal gas across all levels of description. The structural consistency between the united-atom and mesoscale descriptions means the relative entropy between descriptions has been minimized without any variational optimization parameters. The approach is general and applicable to any polymeric system in different thermodynamic conditions.

  13. An analytical coarse-graining method which preserves the free energy, structural correlations, and thermodynamic state of polymer melts from the atomistic to the mesoscale

    E-Print Network [OSTI]

    J. McCarty; A. J. Clark; J. Copperman; M. G. Guenza

    2014-07-03

    Structural and thermodynamic consistency of coarse-graining models across multiple length scales is essential for the predictive role of multi-scale modeling and molecular dynamic simulations that use mesoscale descriptions. Our approach is a coarse-grained model based on integral equation theory, which can represent polymer chains at variable levels of chemical details. The model is analytical and depends on molecular and thermodynamic parameters of the system under study, as well as on the direct correlation function in the k --> 0 limit, c0. A numerical solution to the PRISM integral equations is used to determine c0, by adjusting the value of the effective hard sphere diameter, d, to agree with the predicted equation of state. This single quantity parameterizes the coarse-grained potential, which is used to perform mesoscale simulations that are directly compared with atomistic-level simulations of the same system. We test our coarse-graining formalism by comparing structural correlations, isothermal compressibility, equation of state, Helmholtz and Gibbs free energies, and potential energy and entropy using both united atom and coarse-grained descriptions. We find quantitative agreement between the analytical formalism for the thermodynamic properties, and the results of Molecular Dynamics simulations, independent of the chosen level of representation. In the mesoscale description, the potential energy of the soft-particle interaction becomes a free energy in the coarse-grained coordinates which preserves the excess free energy from an ideal gas across all levels of description. The structural consistency between the united-atom and mesoscale descriptions means the relative entropy between descriptions has been minimized without any variational optimization parameters. The approach is general and applicable to any polymeric system in different thermodynamic conditions.

  14. Midlatitude Continental Convective Clouds Experiment (MC3E)

    SciTech Connect (OSTI)

    Jensen, MP; Petersen, WA; Del Genio, AD; Giangrande, SE; Heymsfield, A; Heymsfield, G; Hou, AY; Kollias, P; Orr, B; Rutledge, SA; Schwaller, MR; Zipser, E

    2010-04-01

    Convective processes play a critical role in the Earth’s energy balance through the redistribution of heat and moisture in the atmosphere and subsequent impacts on the hydrologic cycle. Global observation and accurate representation of these processes in numerical models is vital to improving our current understanding and future simulations of Earth’s climate system. Despite improvements in computing power, current operational weather and global climate models are unable to resolve the natural temporal and spatial scales that are associated with convective and stratiform precipitation processes; therefore, they must turn to parameterization schemes to represent these processes. In turn, the physical basis for these parameterization schemes needs to be evaluated for general application under a variety of atmospheric conditions. Analogously, space-based remote sensing algorithms designed to retrieve related cloud and precipitation information for use in hydrological, climate, and numerical weather prediction applications often rely on physical “parameterizations” that reliably translate indirectly related instrument measurements to the physical quantity of interest (e.g., precipitation rate). Importantly, both spaceborne retrieval algorithms and model convective parameterization schemes traditionally rely on field campaign data sets as a basis for evaluating and improving the physics of their respective approaches. The Midlatitude Continental Convective Clouds Experiment (MC3E) will take place in central Oklahoma during the April–May 2011 period. The experiment is a collaborative effort between the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility and the National Aeronautics and Space Administration’s (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The field campaign leverages the unprecedented observing infrastructure currently available in the central United States, combined with an extensive sounding array, remote sensing and in situ aircraft observations, NASA GPM ground validation remote sensors, and new ARM instrumentation purchased with American Recovery and Reinvestment Act funding. The overarching goal is to provide the most complete characterization of convective cloud systems, precipitation, and the environment that has ever been obtained, providing constraints for model cumulus parameterizations and space-based rainfall retrieval algorithms over land that have never before been available. Several different components of convective cloud and precipitation processes tangible to both the convective parameterization and precipitation retrieval algorithm problem are targeted, such as preconvective environment and convective initiation, updraft/downdraft dynamics, condensate transport and detrainment, precipitation and cloud microphysics, spatial and temporal variability of precipitation, influence on the environment and radiation, and a detailed description of the large-scale forcing.

  15. Dynamics of Mesoscale Magnetic Field in Diffusive Shock Acceleration

    E-Print Network [OSTI]

    P. H. Diamond; M. A. Malkov

    2006-05-15

    We present a theory for the generation of mesoscale ($kr_{g}\\ll 1$, where $r_{g}$ is the cosmic ray gyroradius) magnetic fields during diffusive shock acceleration. The decay or modulational instability of resonantly excited Alfven waves scattering off ambient density perturbations in the shock environment naturally generates larger scale fields. For a broad spectrum of perturbations, the physical mechanism of energy transfer is random refraction, represented by diffusion of Alfven wave packet in $k-$space. The scattering field can be produced directly by the decay instability or by the Drury instability, a hydrodynamic instability driven by the cosmic ray pressure gradient. This process is of interest to acceleration since it generates waves of longer wavelength, and so enables the confinement and acceleration of higher energy particles. This process also limits the intensity of resonantly generated turbulent magnetic field on $r_{g}$ scales.

  16. Mesoscale modeling of colloidal suspensions with adsorbing solutes

    E-Print Network [OSTI]

    Rei Tatsumi; Osamu Koike; Yukio Yamaguchi

    2015-01-14

    We construct a mesoscale model of colloidal suspensions that contain solutes reversibly adsorbing onto the colloidal particle surfaces. The present model describes the coupled dynamics of the colloidal particles, the host fluid, and the solutes through the Newton-Euler equations of motion, the hydrodynamic equations, and the advection-diffusion equation, respectively. The solute adsorption is modeled through a square-well potential, which represents a short-range attractive interaction between a particle and a solute molecule. The present model is formulated to be solved through direct numerical simulations. Some numerical results are presented to validate the simulations. The present model enables investigations of solute adsorption effects in the presence of a fluid flow and an inhomogeneous solute concentration distribution.

  17. Mesoscale polycrystal calculations of damage in spallation in metals

    SciTech Connect (OSTI)

    Tonks, Davis L [Los Alamos National Laboratory; Bingert, John F [Los Alamos National Laboratory; Livescu, Veronica [Los Alamos National Laboratory; Luo, Shengnian [Los Alamos National Laboratory; Bronkhorst, C A [Los Alamos National Laboratory

    2010-01-01

    The goal of this project is to produce a damage model for spallation in metals informed by the polycrystalline grain structure at the mesoscale. Earlier damage models addressed the continuwn macroscale in which these effects were averaged out. In this work we focus on cross sections from recovered samples examined with EBSD (electron backscattered diffraction), which reveal crystal grain orientations and voids. We seek to understand the loading histories of specific sample regions by meshing up the crystal grain structure of these regions and simulating the stress, strain, and damage histories in our hydro code, FLAG. The stresses and strain histories are the fundamental drivers of damage and must be calculated. The calculated final damage structures are compared with those from the recovered samples to validate the simulations.

  18. Strain in the mesoscale kinetic Monte Carlo model for sintering

    E-Print Network [OSTI]

    Bjørk, R; Tikare, V; Olevsky, E; Pryds, N

    2014-01-01

    Shrinkage strains measured from microstructural simulations using the mesoscale kinetic Monte Carlo (kMC) model for solid state sintering are discussed. This model represents the microstructure using digitized discrete sites that are either grain or pore sites. The algorithm used to simulate densification by vacancy annihilation removes an isolated pore site at a grain boundary and collapses a column of sites extending from the vacancy to the surface of sintering compact, through the center of mass of the nearest grain. Using this algorithm, the existing published kMC models are shown to produce anisotropic strains for homogeneous powder compacts with aspect ratios different from unity. It is shown that the line direction biases shrinkage strains in proportion the compact dimension aspect ratios. A new algorithm that corrects this bias in strains is proposed; the direction for collapsing the column is determined by choosing a random sample face and subsequently a random point on that face as the end point for...

  19. Chaotic flow in a 2D natural convection loop with heat flux boundaries William F. Louisos a,b,

    E-Print Network [OSTI]

    Danforth, Chris

    . Examples of natural convection cells occurring in engineering devices include solar water heaters, nu into the system while the upper half is cooled by an equal-but- opposite heat flux out of the system. Water between landmass and an adjacent body of water; mantle convection of the Earth's asthenosphere which

  20. J2.3 USING SPATIOTEMPORAL RELATIONAL DATA MINING TO IDENTIFY THE KEY PARAMETERS FOR ANTICIPATING ROTATION INITIATION IN

    E-Print Network [OSTI]

    McGovern, Amy

    1 and cause, in part, the $13B (Pielke and Carbone, 2002) of economic impact due to mesoscale storms. The current primary instrumentation for observing mesoscale convection is the WSR- 88D NEXRAD radar system system for mesoscale data (Xue et al. 2000, 2001, 2003). When assimilated data is available in larger

  1. Design of a high-speed, meso-scale nanopositioners driven by electromagnetic actuators

    E-Print Network [OSTI]

    Golda, Dariusz, 1979-

    2008-01-01

    The purpose of this thesis is to generate the design and fabrication knowledge that is required to engineer high-speed, six-axis, meso-scale nanopositioners that are driven by electromagnetic actuators. When compared to ...

  2. Enhancement of Mesoscale Eddy Stirring at Steering Levels in the Southern Ocean

    E-Print Network [OSTI]

    Marshall, John C.

    Meridional cross sections of effective diffusivity in the Southern Ocean are presented and discussed. The effective diffusivity, K[subscript eff], characterizes the rate at which mesoscale eddies stir properties on interior ...

  3. Tests of an ensemble Kalman filter for mesoscale and regional-scale data assimilation 

    E-Print Network [OSTI]

    Meng, Zhiyong

    2007-09-17

    This dissertation examines the performance of an ensemble Kalman filter (EnKF) implemented in a mesoscale model in increasingly realistic contexts from under a perfect model assumption and in the presence of significant model error with synthetic...

  4. Rationalizing the Spatial Distribution of Mesoscale Eddy Diffusivity in Terms of Mixing Length Theory

    E-Print Network [OSTI]

    Bates, Michael

    Observations and theory suggest that lateral mixing by mesoscale ocean eddies only reaches its maximum potential at steering levels, surfaces at which the propagation speed of eddies approaches that of the mean flow. Away ...

  5. Coastal Wave Generation and Wave Breaking over Terrain: Two Problems in Mesoscale Wave Dynamics 

    E-Print Network [OSTI]

    Qian, Tingting

    2010-07-14

    Two problems in mesoscale wave dynamics are addressed: (i) wave-turbulence interaction in a breaking mountain wave and (ii) gravity wave generation associated with coastal heating gradients. The mean and turbulent structures in a breaking mountain...

  6. Mesoscale fracture fabric and paleostress along the San Andreas fault at SAFOD 

    E-Print Network [OSTI]

    Almeida, Rafael Vladimir

    2009-05-15

    Spot cores from Phase 1 drilling of the main borehole at the San Andreas Fault Observatory at Depth (SAFOD) were mapped to characterize the mesoscale structure and infer paleostress at depth. Cores were oriented by comparing ...

  7. Characteristics of convective cells over the coastal regions of southeast Texas 

    E-Print Network [OSTI]

    Robinson, Michael

    1998-01-01

    Vertical profiles of radar reflectivity and cloud-to-ground lightning characteristics associated with convective cells were analyzed for mesoscate systems occurring over the coastal regions of southeast Texas during the ...

  8. Representation of the mesoscale wind field using a line integral technique 

    E-Print Network [OSTI]

    Trares, John S

    1982-01-01

    REPPESENTATION OF THE MESOSCALE WIND FIELD USING A LINE INTEGRAL TECHNII1UE A Thesis by JOHN SEBASTIAN TRARES, JR. Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER... t May 1982 ABSTRACT Representation of the Mesoscale Wind Field Using a Line Integral Technique. (May 1982) John Sebastian Trares, Jr. , B. S. , University of Missouri Chairman of Advisory Committee: Or. Phanindramohan Das An interpolated...

  9. Mesoscale divergence, vorticity, and vertical motion compared to radar and rainfall patterns 

    E-Print Network [OSTI]

    Withers, Donald Mead

    1971-01-01

    !e degree of PIASTER OF SCIENCE August 1971 Major Subject: PJeteorology MESOSCALE DIVERGENCE& VORTICITY& AND VERTICAL MOTION COMPARED TO RADAR AND RAINI'ALL PATTERNS A Thesis by DONALD MEAD NITHERS Approved as to style and content by: 88.... ( (Chairman of Committee) (Member) (Head of Depa ent) (Member) August 1971 ASS TRACT Mesoscale Divergence, Vorticity, and Vertica] Motion Compared to Radar and Rainfall Patterns. (August 1971) Donald Mead Nithers, B. S. , University of Oklahoma...

  10. Development and validation of a vertically two-dimensional mesoscale numerical model 

    E-Print Network [OSTI]

    Walters, Michael Kent

    1985-01-01

    DEVELOPMENT AND VALIDATION OF A VERTICALLY TWO-DIMENSIONAL MESOSCALE NUMERICAL MODEL A Thesis by MICHAEL KENT WALTERS Submitted to the Graduate College of Texas AsM University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE August 1985 Major Subject: Meteorology DEVELOPMENT AND VALIDATION OF A VERTICALLY TWO-DIMENSIONAL MESOSCALE NUMERICAL MODEL A Thesis by MICHAEL KENT WALTERS Approved as to style and content by: Dusan Djuric (Chair of Committee) WP...

  11. Moist processes and the quasi-hydrostatic approximation in a mesoscale numerical model 

    E-Print Network [OSTI]

    Kennedy, Charles Joseph

    1987-01-01

    MOIST PROCESSES AND THE QUASI-HYDROSTATIC APPROXIMATION IN A MESOSCALE NUMERICAL MODEL A Thesis by CHARLES JOSEPH KENNEDY Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE December 1987 Major Subject: Meteorology MOIST PROCESSES AND THE QUASI-HYDROSTATIC APPROXIMATION IN A MESOSCALE NUMERICAL MODEL A Thesis by CHARLES JOSEPH KENNEDY Approved as to style and content by: Dusan Djuric (Chair...

  12. A study of wind variability in the lower troposphere through power spectrum analysis at mesoscale frequencies 

    E-Print Network [OSTI]

    Cornett, John Sheldon

    1966-01-01

    A STUDY OF WIND VARIABILITY IN THE LOWER TROPOSPHERE THROUGH POWER SPECTRUM ANALYSIS AT MESOSCALE FREQUENCIES A Thesis By JOHN SHELDON CORNETT Submitted to the Graduate College of the Texas A&M University in Partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE January 1966 Major Subject: Meteorology A STUDY OP WIND VARIABILITY IN THE LOWER TROPOSPHERE THROUGH POWER SPECTRUM ANALYSIS AT MESOSCALE FREQUENCIES A Thesis By JOHN SHELDON CORNETT Approved as to style...

  13. Interactions between cumulus convection and its environment as revealed by the MC3E sounding array

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xie, Shaocheng; Zhang, Yunyan; Giangrande, Scott E.; Jensen, Michael P.; McCoy, Renata; Zhang, Minghua

    2014-10-27

    This study attempts to understand interactions between midlatitude convective systems and their environments through a heat and moisture budget analysis using the sounding data collected from the Midlatitude Continental Convective Clouds Experiment (MC3E) in central Oklahoma. Distinct large-scale structures and diabatic heating and drying profiles are presented for cases of weaker and elevated thunderstorms as well as intense squall line and supercell thunderstorm events during the campaign. The elevated cell events were nocturnal convective systems occurring in an environment having low convective available potential energy (CAPE) and a very dry boundary layer. In contrast, deeper convective events happened during themore »morning into early afternoon within an environment associated with large CAPE and a near-saturated boundary layer. As the systems reached maturity, the diagnosed diabatic heating in the latter deep convective cases was much stronger and of greater vertical extent than the former. Both groups showed considerable diabatic cooling in the lower troposphere, associated with the evaporation of precipitation and low-level clouds. The horizontal advection of moisture also played a dominant role in moistening the lower troposphere, particularly for the deeper convective events, wherein the near surface southeasterly flow allows persistent low-level moisture return from the Gulf of Mexico to support convection. The moisture convergence often was present before these systems develop, suggesting a strong correlation between the large-scale moisture convergence and convection. As a result, sensitivity tests indicated that the uncertainty in the surface precipitation and the size of analysis domain mainly affected the magnitude of these analyzed fields rather than their vertical structures.« less

  14. Interactions between Cumulus Convection and Its Environment as Revealed by the MC3E Sounding Array

    SciTech Connect (OSTI)

    Xie, Shaocheng [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Jensen, Michael P. [Brookhaven National Laboratory (BNL), Upton, NY (United States); Zhang, Yunyan [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Giangrande, Scott E. [Brookhaven National Laboratory (BNL), Upton, NY (United States); McCoy, Renata [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Zhang, Minghua [Stony Brook Univ., Stony Brook, NY (United States)

    2014-10-27

    This study attempts to understand interactions between midlatitude convective systems and their environments through a heat and moisture budget analysis using the sounding data collected from the Midlatitude Continental Convective Clouds Experiment (MC3E) in central Oklahoma. Distinct large-scale structures and diabatic heating and drying profiles are presented for cases of weaker and elevated thunderstorms as well as intense squall line and supercell thunderstorm events during the campaign. The elevated cell events were nocturnal convective systems occurring in an environment having low convective available potential energy (CAPE) and a very dry boundary layer. In contrast, deeper convective events happened during the morning into early afternoon within an environment associated with large CAPE and a near-saturated boundary layer. As the systems reached maturity, the diagnosed diabatic heating in the latter deep convective cases was much stronger and of greater vertical extent than the former. Both groups showed considerable diabatic cooling in the lower troposphere, associated with the evaporation of precipitation and low-level clouds. The horizontal advection of moisture also played a dominant role in moistening the lower troposphere, particularly for the deeper convective events, wherein the near surface southeasterly flow allows persistent low-level moisture return from the Gulf of Mexico to support convection. The moisture convergence often was present before these systems develop, suggesting a strong correlation between the large-scale moisture convergence and convection. Sensitivity tests indicated that the uncertainty in the surface precipitation and the size of analysis domain mainly affected the magnitude of these analyzed fields rather than their vertical structures.

  15. Impact of the Position of a Radiator to Energy Consumption and Thermal Comfort in a Mixed Radiant and Convective Heating System 

    E-Print Network [OSTI]

    Gong, X.; Claridge, D. E.

    2005-01-01

    Heating energy consumption in winter is an important component of the whole building energy consumption in the severe cold zone in north China. This paper presents a heating water system of a hotel building in Harbin, finishes the testing of its...

  16. Mesoscale Structures at Complex Fluid-Fluid Interfaces: a Novel Lattice Boltzmann / Molecular Dynamics Coupling

    E-Print Network [OSTI]

    Marcello Sega; Mauro Sbragaglia; Sofia Sergeevna Kantorovich; Alexey Olegovich Ivanov

    2014-02-19

    Complex fluid-fluid interfaces featuring mesoscale structures with adsorbed particles are key components of newly designed materials which are continuously enriching the field of soft matter. Simulation tools which are able to cope with the different scales characterizing these systems are fundamental requirements for efficient theoretical investigations. In this paper we present a novel simulation method, based on the approach of Ahlrichs and D\\"unweg [Ahlrichs and D\\"unweg, Int. J. Mod. Phys. C, 1998, 9, 1429], that couples the "Shan-Chen" multicomponent Lattice Boltzmann technique to off-lattice molecular dynamics to simulate efficiently complex fluid-fluid interfaces. We demonstrate how this approach can be used to study a wide class of challenging problems. Several examples are given, with an accent on bicontinuous phases formation in polyelectrolyte solutions and ferrofluid emulsions. We also show that the introduction of solvation free energies in the particle-fluid interaction unveils the hidden, multiscale nature of the particle-fluid coupling, allowing to treat symmetrically (and interchangeably) the on-lattice and off-lattice components of the system.

  17. Development of Ensemble Neural Network Convection Parameterizations for Climate Models

    SciTech Connect (OSTI)

    Fox-Rabinovitz, M. S.; Krasnopolsky, V. M.

    2012-05-02

    The novel neural network (NN) approach has been formulated and used for development of a NN ensemble stochastic convection parametrization for climate models. This fast parametrization is built based on data from Cloud Resolving Model (CRM) simulations initialized with and forced by TOGA-COARE data. The SAM (System for Atmospheric Modeling), developed by D. Randall, M. Khairoutdinov, and their collaborators, has been used for CRM simulations. The observational data are also used for validation of model simulations. The SAM-simulated data have been averaged and projected onto the GCM space of atmospheric states to implicitly define a stochastic convection parametrization. This parametrization is emulated using an ensemble of NNs. An ensemble of NNs with different NN parameters has been trained and tested. The inherent uncertainty of the stochastic convection parametrization derived in such a way is estimated. Due to these inherent uncertainties, NN ensemble is used to constitute a stochastic NN convection parametrization. The developed NN convection parametrization have been validated in a diagnostic CAM (CAM-NN) run vs. the control CAM run. Actually, CAM inputs have been used, at every time step of the control/original CAM integration, for parallel calculations of the NN convection parametrization (CAM-NN) to produce its outputs as a diagnostic byproduct. Total precipitation (P) and cloudiness (CLD) time series, diurnal cycles, and P and CLD distributions for the large Tropical Pacific Ocean for the parallel CAM-NN and CAM runs show similarity and consistency with the NCEP reanalysis. The P and CLD distributions for the tropical area for the parallel runs have been analyzed first for the TOGA-COARE boreal winter season (November 1992 through February 1993) and then for the winter seasons of the follow-up parallel decadal simulations. The obtained results are encouraging and practically meaningful. They show the validity of the NN approach. This constitutes an important practical conclusion of the study: the obtained results on NN ensembles as a stochastic physics parametrization show a realistic possibility of development of NN convection parametrization for climate (and NWP) models based on learning cloud physics from CRM/SAM simulated data.

  18. MICRO-SEISMOMETERS VIA ADVANCED MESO-SCALE FABRICATION

    SciTech Connect (OSTI)

    Garcia, Caesar A; Onaran, Guclu; Avenson, Brad; Hall, Neal

    2014-11-07

    The Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) seek revolutionary sensing innovations for the monitoring of nuclear detonations. Performance specifications are to be consistent with those obtainable by only an elite few products available today, but with orders of magnitude reduction in size, weight, power, and cost. The proposed commercial innovation calls upon several technologies including the combination of meso-scale fabrication and assembly, photonics-based displacement / motion detection methods, and the use of digital control electronics . Early Phase II development has demonstrated verified and repeatable sub 2ng noise floor from 3Hz to 100Hz, compact integration of 3-axis prototypes, and robust deployment exercises. Ongoing developments are focusing on low frequency challenges, low power consumption, ultra-miniature size, and low cross axis sensitivity. We are also addressing the rigorous set of specifications required for repeatable and reliable long-term explosion monitoring, including thermal stability, reduced recovery time from mass re-centering and large mechanical shocks, sensitivity stability, and transportability. Successful implementation will result in small, hand-held demonstration units with the ability to address national security needs of the DOE/NNSA. Additional applications envisioned include military/defense, scientific instrumentation, oil and gas exploration, inertial navigation, and civil infrastructure monitoring.

  19. Emergent Mesoscale Phenomena in Magnetized Accretion Disc Turbulence

    E-Print Network [OSTI]

    Simon, Jacob B; Armitage, Philip J

    2012-01-01

    We study how the structure and variability of magnetohydrodynamic (MHD) turbulence in accretion discs converge with domain size. Our results are based on a series of vertically stratified local simulations, computed using the Athena code, that have fixed spatial resolution, but varying radial and azimuthal extent (from \\Delta R = 0.5H to 16H, where H is the vertical scale height). We show that elementary local diagnostics of the turbulence, including the Shakura-Sunyaev {\\alpha} parameter, the ratio of Maxwell stress to magnetic energy, and the ratio of magnetic to fluid stresses, converge to within the precision of our measurements for spatial domains of radial size Lx \\geq 2H. We obtain {\\alpha} = 0.02-0.03, consistent with recent results. Very small domains (Lx = 0.5H) return anomalous results, independent of spatial resolution. The convergence with domain size is only valid for a limited set of diagnostics: larger spatial domains admit the emergence of dynamically important mesoscale structures. In our la...

  20. Mesoscale and Large-Eddy Simulations for Wind Energy

    SciTech Connect (OSTI)

    Marjanovic, N

    2011-02-22

    Operational wind power forecasting, turbine micrositing, and turbine design require high-resolution simulations of atmospheric flow over complex terrain. The use of both Reynolds-Averaged Navier Stokes (RANS) and large-eddy (LES) simulations is explored for wind energy applications using the Weather Research and Forecasting (WRF) model. To adequately resolve terrain and turbulence in the atmospheric boundary layer, grid nesting is used to refine the grid from mesoscale to finer scales. This paper examines the performance of the grid nesting configuration, turbulence closures, and resolution (up to as fine as 100 m horizontal spacing) for simulations of synoptically and locally driven wind ramping events at a West Coast North American wind farm. Interestingly, little improvement is found when using higher resolution simulations or better resolved turbulence closures in comparison to observation data available for this particular site. This is true for week-long simulations as well, where finer resolution runs show only small changes in the distribution of wind speeds or turbulence intensities. It appears that the relatively simple topography of this site is adequately resolved by all model grids (even as coarse as 2.7 km) so that all resolutions are able to model the physics at similar accuracy. The accuracy of the results is shown in this paper to be more dependent on the parameterization of the land-surface characteristics such as soil moisture rather than on grid resolution.

  1. Experimental study of internal wave generation by convection in water

    E-Print Network [OSTI]

    2015-01-01

    study of internal wave generation by convection in waterstudies of internal wave generation by convective turbulenceintermittent generation of internal waves. We also computed

  2. The reduction of plankton biomass induced by mesoscale stirring: a modeling study in the Benguela upwelling

    E-Print Network [OSTI]

    Ismael Hernández-Carrasco; Vincent Rossi; Emilio Hernández-García; Veronique Garçon; Cristóbal López

    2013-11-05

    Recent studies, both based on remote sensed data and coupled models, showed a reduction of biological productivity due to vigorous horizontal stirring in upwelling areas. In order to better understand this phenomenon, we consider a system of oceanic flow from the Benguela area coupled with a simple biogeochemical model of Nutrient-Phyto-Zooplankton (NPZ) type. For the flow three different surface velocity fields are considered: one derived from satellite altimetry data, and the other two from a regional numerical model at two different spatial resolutions. We compute horizontal particle dispersion in terms of Lyapunov Exponents, and analyzed their correlations with phytoplankton concentrations. Our modelling approach confirms that in the south Benguela there is a reduction of biological activity when stirring is increased. Two-dimensional offshore advection and latitudinal difference in Primary Production, also mediated by the flow, seem to be the dominant processes involved. We estimate that mesoscale processes are responsible for 30 to 50% of the offshore fluxes of biological tracers. In the northern area, other factors not taken into account in our simulation are influencing the ecosystem. We suggest explanations for these results in the context of studies performed in other eastern boundary upwelling areas.

  3. The Impacts of Indirect Soil Moisture Assimilation and Direct Surface Temperature and Humidity Assimilation on a Mesoscale Model Simulation of an Indian

    E-Print Network [OSTI]

    Niyogi, Dev

    Assimilation on a Mesoscale Model Simulation of an Indian Monsoon Depression VINODKUMAR AND A. CHANDRASEKAR-generation Pennsylvania State University­NCAR Mesoscale Model (MM5) simulation utilized the humidity and temperature

  4. Bull. Disas. Prey. Res. Inst., Kyoto Univ., Vol. 45, Part 2,3 No. 391, February, 1996 61 A Simple Water Balance Model for a Mesoscale Catchment

    E-Print Network [OSTI]

    Takada, Shoji

    A Simple Water Balance Model for a Mesoscale Catchment Based on Heterogeneous Soil Water Storage Capacity, for the mesoscale catchments of Japan and Thailand. Sensitivity analysis of the model parameters has been conducted

  5. Mesoscale Variations of the Atmospheric Snow Line over the Northern Sierra Nevada: Multiyear Statistics, Case Study, and Mechanisms

    E-Print Network [OSTI]

    Minder, Justin

    Mesoscale Variations of the Atmospheric Snow Line over the Northern Sierra Nevada: Multiyear to rainfall, the snow line, can intersect the terrain at an elevation hundreds of meters below its elevation in the free air upwind. This mesoscale lowering of the snow line affects both the accumulation of mountain

  6. arXiv:1207.3736v1[math.DS]16Jul2012 Meso-scale obstructions to

    E-Print Network [OSTI]

    arXiv:1207.3736v1[math.DS]16Jul2012 Meso-scale obstructions to stability of 1D center manifolds, the impact of meso-scale structural properties on the dynamics of complex networks. As a motivational exam

  7. Convective heat transfer inside passive solar buildings

    SciTech Connect (OSTI)

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

    1983-11-01

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

  8. Convective heat transfer inside passive solar buildings

    SciTech Connect (OSTI)

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

    1983-01-01

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

  9. Transient Mixed Convection Validation for NGNP

    SciTech Connect (OSTI)

    Smith, Barton; Schultz, Richard

    2015-10-19

    The results of this project are best described by the papers and dissertations that resulted from the work. They are included in their entirety in this document. They are: (1) Jeff Harris PhD dissertation (focused mainly on forced convection); (2) Blake Lance PhD dissertation (focused mainly on mixed and transient convection). This dissertation is in multi-paper format and includes the article currently submitted and one to be submitted shortly; and, (3) JFE paper on CFD Validation Benchmark for Forced Convection.

  10. Analyses of the role of grain boundaries in mesoscale dynamic fracture resistance of SiCSi3N4 intergranular nanocomposites

    E-Print Network [OSTI]

    Tomar, Vikas

    Analyses of the role of grain boundaries in mesoscale dynamic fracture resistance of SiC­Si3N4 with SiC dispersions as well as Si3N4 matrix of mesoscale dimensions ($1 lm) are considered to have, cohesive finite element method (CFEM) based mesoscale dynamic fracture anal- yses of SiC­Si3N4

  11. Generated using version 3.2 of the official AMS LATEX template Mesoscale Predictability and Initial-Condition Error Growth in1

    E-Print Network [OSTI]

    Generated using version 3.2 of the official AMS LATEX template Mesoscale Predictability and Initial;ABSTRACT5 Early investigations suggested that mesoscale atmospheric motions would have very limited6 cascade. In contrast, subsequent studies proposed that many mesoscale cir-8 culations inherit

  12. Effects of urban land cover modifications in a mesoscale meteorological model on surface temperature and heat fluxes in the Phoenix metropolitan area.

    E-Print Network [OSTI]

    Hall, Sharon J.

    Effects of urban land cover modifications in a mesoscale meteorological model on surface between the two simulations. Mesoscale atmospheric models such as the Pennsylvania State University for the Phoenix metropolitan area was implemented in the fifth- generation PSU/NCAR mesoscale meteorological model

  13. Bull. Disas. Prey. Res. Inst., Kyoto Univ., Vol. 45, Part 2,3 No 390, February, 1996 39 Mesoscale Numerical Study over the HEIFE Area

    E-Print Network [OSTI]

    Takada, Shoji

    Mesoscale Numerical Study over the HEIFE Area Part 1: Three Dimensional Wind Field By Zhong CHEN1),Jiayi, 1996) Abstract In this study the three dimensional mesoscale model, which is based on the Peking University Mesoscale Model, was used to simulate the wind field in the HEIFE experimental region. Simulations

  14. Mesoscale Patterns Formed by Evaporation of a Polymer Solution in the Proximity of a Sphere on a Smooth Substrate: Molecular Weight

    E-Print Network [OSTI]

    Lin, Zhiqun

    Mesoscale Patterns Formed by Evaporation of a Polymer Solution in the Proximity of a Sphere evaporation as a simple, lithography- and external-field- free route to well-ordered mesoscale structures weight (MW) effect on the mesoscale polymer patterns formed by drying a drop of polymer solution

  15. Mesoscale model cloud scheme assessment using satellite observations Jean-Pierre Chaboureau, Jean-Pierre Cammas, Patrick J. Mascart, and Jean-Pierre Pinty

    E-Print Network [OSTI]

    Chaboureau, Jean-Pierre

    Mesoscale model cloud scheme assessment using satellite observations Jean-Pierre Chaboureau, Jean of the mesoscale nonhydrostatic (Meso-NH) model has been conducted by comparing synthetic METEOSAT brightness combines the output from a bulk explicit cloud scheme routinely used in mesoscale simulations

  16. REVIEWS OF GEOPHYSICS: U.S. NATIONAL REPORT TO INTERNATIONAL UNION OF GEODESY AND GEOPHYSICS COOL SEASON CYCLOGENESIS AND ASSOCIATED MESOSCALE WEATHER

    E-Print Network [OSTI]

    Businger, Steven

    -1994 COOL SEASON CYCLOGENESIS AND ASSOCIATED MESOSCALE WEATHER Steven Businger Department of Meteorology (NWS) and a profusion of recent field experiments1 are bringing an explosion of mesoscale2 observations to probe the mesoscale structure and evolution of winter cyclones in recent years. Many recent advances

  17. A STUDY OF ICE ACCUMULATION AND STABILITY IN MARTIAN CRATERS UNDER PAST ORBITAL CONDITIONS USING THE LMD MESOSCALE MODEL. J.-B. Madeleine1

    E-Print Network [OSTI]

    Madeleine, Jean-Baptiste

    THE LMD MESOSCALE MODEL. J.-B. Madeleine1 , J. W. Head1 , A. Spiga2 , J. L. Dickson1 and F. Forget2 , 1 formed, using geolog- ical observations [e.g., 1-4] and mesoscale climate simulations [5 provide essential constraints on the mesoscale climate which prevailed during their formation

  18. arXiv:1205.6074v1[physics.bio-ph]28May2012 Mesoscale symmetries explain dynamical equivalence of food webs

    E-Print Network [OSTI]

    arXiv:1205.6074v1[physics.bio-ph]28May2012 Mesoscale symmetries explain dynamical equivalence is to identify mesoscale structures that have distinct dynamical implications. In this paper we present show that this equivalence is rooted in mesoscale symmetries that exist in these webs. Certain

  19. Journal of the Meteorological Society of Japan, Vol. 82, No. 5, pp. 1389--1397, 2004 1389 Mesoscale Assimilation of TMI Rainfall Data with 4DVAR

    E-Print Network [OSTI]

    Pu, Zhaoxia

    Journal of the Meteorological Society of Japan, Vol. 82, No. 5, pp. 1389--1397, 2004 1389 Mesoscale rainfall data into a mesoscale model, using a four-dimensional variational data assimilation (4DVAR on mesoscale forecasts (e.g., Supertyphoon Paka in 1997 (Pu et al. 2002)), as the global analysis provide

  20. Interannual variability of summer biochemical enhancement in relation to mesoscale eddies at the shelf break in the vicinity of the Pribilof Islands,

    E-Print Network [OSTI]

    Interannual variability of summer biochemical enhancement in relation to mesoscale eddies the 1300-km-long eastern shelf break accompanied by a mesoscale eddy field (Okkonen, 2001a). Eddies occur., 2002). Mesoscale eddies, which penetrate to depths of at least 1000 m (Roden, 1995; Mizobata et al

  1. Dynamical model of mesoscales in z-coordinates V.M. Canuto a,b,*, M.S. Dubovikov a,c

    E-Print Network [OSTI]

    Dynamical model of mesoscales in z-coordinates V.M. Canuto a,b,*, M.S. Dubovikov a,c a NASA Abstract Using the equations of the dynamical mesoscale model developed previously [Ocean Modell. (2004) 8, 1­ 30], we derive a mesoscale model in z-coordinates to be used in coarse resolution OGCMs. We

  2. Steering in computational science: mesoscale modelling and J. CHIN{, J. HARTING{, S. JHA{, P. V. COVENEY{, A. R. PORTER{ and S. M. PICKLES{{

    E-Print Network [OSTI]

    Harting, Jens

    Steering in computational science: mesoscale modelling and simulation J. CHIN{, J. HARTING{, S. JHA steering for high performance computing applications. Lattice-Boltzmann mesoscale fluid simulations, there is currently considerable interest in mesoscale models. These models coarse grain most of the atomic

  3. Mesoscale Predictability of an Extreme Warm-Season Precipitation Event FUQING ZHANG, ANDREW M. ODINS, AND JOHN W. NIELSEN-GAMMON

    E-Print Network [OSTI]

    Mesoscale Predictability of an Extreme Warm-Season Precipitation Event FUQING ZHANG, ANDREW M Station, Texas (Manuscript received 22 November 2004, in final form 28 August 2005) ABSTRACT A mesoscale model is used to investigate the mesoscale predictability of an extreme precipitation event over central

  4. Midlatitude Continental Convective Clouds Experiment (MC3E)

    SciTech Connect (OSTI)

    Jensen, MP; Petersen, WA; Del Genio, AD; Giangrande, SE; Heymsfield, A; Heymsfield, G; Hou, AY; Kollias, P; Orr, B; Rutledge, SA; Schwaller, MR; Zipser, E

    2010-04-10

    The Midlatitude Continental Convective Clouds Experiment (MC3E) will take place in central Oklahoma during the April–May 2011 period. The experiment is a collaborative effort between the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility and the National Aeronautics and Space Administration’s (NASA) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The field campaign leverages the unprecedented observing infrastructure currently available in the central United States, combined with an extensive sounding array, remote sensing and in situ aircraft observations, NASA GPM ground validation remote sensors, and new ARM instrumentation purchased with American Recovery and Reinvestment Act funding. The overarching goal is to provide the most complete characterization of convective cloud systems, precipitation, and the environment that has ever been obtained, providing constraints for model cumulus parameterizations and space-based rainfall retrieval algorithms over land that have never before been available.

  5. Convective Cooling and Passive Stack Improvements in Motors (Presentation)

    SciTech Connect (OSTI)

    Bennion, K.

    2014-06-01

    This presentation discusses current research at NREL in convective cooling and passive stack improvements in motors.

  6. Vortex Tubes of Turbulent Solar Convection

    E-Print Network [OSTI]

    Kitiashvili, I N; Mansour, N N; Lele, S K; Wray, A A

    2011-01-01

    Investigation of turbulent properties of solar convection is extremely important for understanding of the multi-scale dynamics observed on the solar surface. In particular, recent high-resolution observations revealed ubiquitous vortical structures, and numerical simulations demonstrated links between the vortex tube dynamics and magnetic field organization, and also importance of vortex tube interactions in the mechanism of acoustic wave excitation on the Sun. In this paper we investigate mechanisms of formation of vortex tubes in highly-turbulent convective flows near the solar surface by using realistic radiative hydrodynamic LES simulations. Analysis of data, obtained by the simulations, indicates two basic processes of the vortex tube formation: 1) development of small-scale convective instability inside convective granules, and 2) a Kelvin-Helmholtz type instability of shearing flows in intergranular lanes. Our analysis shows that vortex stretching during these processes is a primary source of generatio...

  7. Circulation and convection in the Irminger Sea

    E-Print Network [OSTI]

    Våge, Kjetil

    2010-01-01

    Aspects of the circulation and convection in the Irminger Sea are investigated using a variety of in-situ, satellite, and atmospheric reanalysis products. Westerly Greenland tip jet events are intense, small-scale wind ...

  8. Stochastic and mesoscopic models for tropical convection

    E-Print Network [OSTI]

    Majda, Andrew J.

    Courant Institute of Mathematical Sciences and Center for Atmosphere and Ocean Sciences, New York penetrative convection to heights of 5­10 km with associated anvil towers of clouds. Observational data

  9. Modeling convection in the Greenland Sea

    E-Print Network [OSTI]

    Bhushan, Vikas

    1998-01-01

    A detailed examination of the development of a deep convection event observed in the Greenland Sea in 1988-89 is carried out through a combination of modeling, scale estimates, and data analysis. We develop a prognostic ...

  10. Convective cores in galactic cooling flows

    E-Print Network [OSTI]

    A. Kritsuk; T. Plewa; E. Mueller

    2001-05-02

    We use hydrodynamic simulations with adaptive grid refinement to study the dependence of hot gas flows in X-ray luminous giant elliptical galaxies on the efficiency of heat supply to the gas. We consider a number of potential heating mechanisms including Type Ia supernovae and sporadic nuclear activity of a central supermassive black hole. As a starting point for this research we use an equilibrium hydrostatic recycling model (Kritsuk 1996). We show that a compact cooling inflow develops, if the heating is slightly insufficient to counterbalance radiative cooling of the hot gas in the central few kiloparsecs. An excessive heating in the centre, instead, drives a convectively unstable outflow. We model the onset of the instability and a quasi-steady convective regime in the core of the galaxy in two-dimensions assuming axial symmetry. Provided the power of net energy supply in the core is not too high, the convection remains subsonic. The convective pattern is dominated by buoyancy driven large-scale mushroom-like structures. Unlike in the case of a cooling inflow, the X-ray surface brightness of an (on average) isentropic convective core does not display a sharp maximum at the centre. A hybrid model, which combines a subsonic peripheral cooling inflow with an inner convective core, appears to be stable. We also discuss observational implications of these results.

  11. Mixed convection heat transfer from thermal sources mounted on horizontal and vertical surfaces

    SciTech Connect (OSTI)

    Tewari, S.S.; Jaluria, Y. )

    1990-11-01

    An experimental study is carried out on the fundamental aspects of the conjugate, mixed convective heat transfer from two finite width heat sources, which are of negligible thickness, have a uniform heat flux input at the surface, and are located on a flat plate in a horizontal or the vertical orientation. The heat sources are wide in the transverse direction and, therefore, a two-dimensional flow circumstance is simulated. The mixed convection parameter is varied over a fairly wide range to include the buoyancy-dominated and the mixed convection regimes. The circumstances of pure natural convection are also investigated. The convective mechanisms have been studied in detail by measuring the surface temperatures and determining the heat transfer coefficients for the two heated strips, which represent isolated thermal sources. Experimental results indicate that a stronger upstream heat source causes an increase in the surface temperature of a relatively weaker heat source, located downstream, by reducing it convective heat transfer coefficient. The influence of the upstream source is found to be strongly dependent on the surface orientation, especially in the pure natural convection and the buoyancy dominated regimes. The two heat sources are found to be essentially independent on the surface orientation, especially in the pure natural convection and the buoyancy dominated regimes. The two heat sources are found to be essentially independent of each other, in terms of thermal effects, at a separation distance of more than about three strip widths for both the orientations. The results obtained are relevant to many engineering applications, such as the cooling of electronic systems, positioning of heating elements in furnaces, and safety considerations in enclosure fires.

  12. Film condensation of saturated and superheated vapors along isothermal vertical surfaces in mixed convection

    SciTech Connect (OSTI)

    Winkler, C.M.; Chen, T.S.; Minkowycz, W.J.

    1999-09-01

    An analysis for condensation from an isothermal vertical flat plate in mixed convection is reported. The entire mixed convection regime is divided into two regions. One region covers the forced-convection-dominated regime, and the other covers the free-convection-dominated regime. The governing system of equations is first transformed into a dimensionless form by the nonsimilar transformation, separately for each regime, and then solved using the local nonsimilarity method along with a finite difference scheme. Two nonsimilarity parameters are introduced. The parameter {xi}{sub f} = Gr{sub x}/Re{sub x}{sup 2} characterizes the effect of buoyancy force on forced convection, while the parameter {xi}{sub n} = Re{sub x}/Gr{sub x}{sup 1/2} characterizes the effect of forced flow on free convection. Numerical results for pure steam and refrigerant R-134a are presented for both saturated and superheated cases. It is found that the buoyancy force significantly increases the wall shear stress and condensate mass flux. To a lesser degree, the buoyancy force also increases the wall heat flux. Superheating is found to have an insignificant effect on wall heat flux for a pure vapor.

  13. Tropical precipitation variability and convectively coupled equatorial waves1 on submonthly time-scales in reanalyses and TRMM2

    E-Print Network [OSTI]

    Alexander, M. Joan

    convection plays a vital role in global climate by driving large-scale circulation,41 releasing latent heat, modulating radiative forcing, and most importantly redistributing water in42 the earth system. Due to complex

  14. Mesoscale modelling for an offshore wind farm Jake Badger*, Rebecca Barthelmie, Sten Frandsen, Merete Bruun Christiansen

    E-Print Network [OSTI]

    Mesoscale modelling for an offshore wind farm Jake Badger*, Rebecca Barthelmie, Sten Frandsen for an offshore wind farm in a coastal location. Spatial gradients and vertical profiles between 25 m and 70 m offshore wind farms tend to be placed within the coastal zone, the region within around 50km from

  15. Mesoscale Spectra of Mars's Atmosphere Derived from MGS TES Infrared Radiances TAKESHI IMAMURA

    E-Print Network [OSTI]

    and potential energy spectra as a function of horizontal wavenumber. Each spectrum has two different wave spectra of the atmospheric potential energy of Mars at mesoscales (wavelengths of 64­957 km) were obtained-scale ends, the spectra sometimes show prominent steepening with slopes from 2 to 3. The power peaks

  16. Are mesoscale eddies in shelf seas formed by baroclinic instability of tidal fronts?

    E-Print Network [OSTI]

    Williams, Ric

    Are mesoscale eddies in shelf seas formed by baroclinic instability of tidal fronts? G. Badin,1 R; accepted 23 July 2009; published 27 October 2009. [1] The formation of eddies along tidal fronts signals are dampened by air-sea interaction and eroded by wind and tidal mixing. High-resolution CTD

  17. Modeling of mesoscale coupled oceanatmosphere interaction and its feedback to ocean in the western Arabian Sea

    E-Print Network [OSTI]

    Jochum, Markus

    horizontal SST gradients in the ocean, developing in response to the southwest monsoon winds. This summertime of the ocean. The observed relationship between the near-surface winds and mesoscale SSTs generate Ekman pump by seasonally reversing monsoonal winds, which drive an in- tense oceanic response off the coast of Africa

  18. Wind ringing of the ocean in presence of mesoscale eddies P. Klein and G. Lapeyre

    E-Print Network [OSTI]

    Lapeyre, Guillaume

    Wind ringing of the ocean in presence of mesoscale eddies P. Klein and G. Lapeyre Laboratoire de frequency (HF) winds on the inertial motions and the consequences on the large-scale oceanic circulation the impact of HF winds on the inertial motions. However the eddies efficiently and permanently concentrate

  19. Analysis and Simulation of a Meso-scale Model of Diffusive Resistance of Bacterial Biofilms to

    E-Print Network [OSTI]

    Demaret, Laurent

    Analysis and Simulation of a Meso-scale Model of Diffusive Resistance of Bacterial Biofilms Most bacteria live in biofilm communities, which offer protection against harmful external impacts mathematical model that focuses on the diffusive resistance that a growing biofilm exerts against penetration

  20. Temporal Changes in Wind as Objects for Evaluating Mesoscale Numerical Weather Prediction

    E-Print Network [OSTI]

    Knievel, Jason Clark

    Temporal Changes in Wind as Objects for Evaluating Mesoscale Numerical Weather Prediction DARAN L changes in simulated and observed 10-m (AGL) winds. The method is demon- strated on a 1-yr collection of 1-day simulations by the fifth-generation Pennsylvania State University­ National Center for Atmospheric

  1. M. Bahrami ENSC 388 (F09) Forced Convection Heat Transfer 1 Forced Convection Heat Transfer

    E-Print Network [OSTI]

    Bahrami, Majid

    surface, and the type of the fluid flow (laminar or turbulent). Fig. 1: Forced convection fluid. Whereas in forced convection, the fluid is forced to flow over a surface or in a tube Boundary Layer Consider the flow of a fluid over a flat plate, the velocity and the temperature

  2. Coupling a Mesoscale Numerical Weather Prediction Model with Large-Eddy Simulation for Realistic Wind Plant Aerodynamics Simulations (Poster)

    SciTech Connect (OSTI)

    Draxl, C.; Churchfield, M.; Mirocha, J.; Lee, S.; Lundquist, J.; Michalakes, J.; Moriarty, P.; Purkayastha, A.; Sprague, M.; Vanderwende, B.

    2014-06-01

    Wind plant aerodynamics are influenced by a combination of microscale and mesoscale phenomena. Incorporating mesoscale atmospheric forcing (e.g., diurnal cycles and frontal passages) into wind plant simulations can lead to a more accurate representation of microscale flows, aerodynamics, and wind turbine/plant performance. Our goal is to couple a numerical weather prediction model that can represent mesoscale flow [specifically the Weather Research and Forecasting model] with a microscale LES model (OpenFOAM) that can predict microscale turbulence and wake losses.

  3. Surface energy fluxes at Central Florida during the convection and precipitation electrification experiment. Final Report

    SciTech Connect (OSTI)

    Nie, D.; Demetriades-shah, T.D.; Kanemasu, E.T.

    1993-04-01

    One of the objectives of CaPE is to better understand the convective process in central and south Florida during the warm season. The energy and moisture exchanges between the surface and the atmosphere are closely related to this process. Some recent studies have shown that the surface energy balance plays an important role in the climatic fields (Shukla and Mintz; Sud and Smith; Sato et. al). Surface energy fluxes and related surface processes such as evapotranspiration and sensible heat transfer directly effect the temperature, humidity, cloud formation and precipitation. For example, mesoscale circulation around a discontinuity in vegetation type were shown to be stronger with wet soil than with dry soil using an evapotranspiration model (Pinty et. al). In order to better describe the processes in the atmosphere at various scales and improve the ability of modeling and predicting weather related events, it is crucial to understand the mechanism of surface energy transfer in relation to atmospheric events. Surface energy flux measurements are required to fully understand the interactions between the atmosphere and the surface.

  4. Laser induced ponderomotive convection in water

    E-Print Network [OSTI]

    Shneider, M N

    2015-01-01

    A new mechanism for inducing convection during IR laser interaction with water or any absorbing polar liquid is described theoretically. The numerical simulations performed using the developed model show that the ponderomotive force produces water flow in the direction of the laser beam propagation. In the later stage of interaction, when water temperature rises, the Archimedes force becomes first comparable and then dominant producing convection directed against the vector of gravitational acceleration (upward). The theoretical estimates and the numerical simulations predict fluid dynamics that is similar to the observed in the previous experiments.

  5. Thermal convection in a liquid metal battery

    E-Print Network [OSTI]

    Shen, Yuxin

    2015-01-01

    Generation of thermal convection flow in the liquid metal battery, a device recently proposed as a promising solution for the problem of the short-term energy storage, is analyzed using a numerical model. It is found that convection caused by Joule heating of electrolyte during charging or discharging is virtually unavoidable. It exists in laboratory prototypes larger than a few cm in size and should become much stronger in larger-scale batteries. The phenomenon needs further investigation in view of its positive (enhanced mixing of reactants) and negative (loss of efficiency and possible disruption of operation due to the flow-induced deformation of the electrolyte layer) effects.

  6. Generation and Trapping of Gravity Waves from Convection with Comparison to Parameterization

    E-Print Network [OSTI]

    Alexander, M. Joan

    Generation and Trapping of Gravity Waves from Convection with Comparison to Parameterization M (GCMs) add realism by describing wave generation by tropospheric convection. Because the convection in GCMs is itself a parameterized process, these convectively generated wave parameterizations necessarily

  7. Numerical models of Rayleigh-Taylor instabilities superimposed upon convection

    E-Print Network [OSTI]

    Schmeling, Harro

    one R.T.-overturn to multiple convective with salt tectonics (R.T.), plutonism (R.T.), plate overturns. Secondly, how is the temperature field tectonics and mantle flows (convection) (see e.g. affected

  8. Layer inflow into precipitating convection over the western tropical Pacific

    E-Print Network [OSTI]

    Mechem, David B.; Houze, Robert A. Jr.; Chen, Shuyi S.

    2002-07-01

    A conceptual model of tropical convection frequently used in convective parametrization schemes is that of a parcel process in which boundary-layer air, characterized by high equivalent potential temperature, ascends to ...

  9. Mixed convection transport from an isolated heat source module on a horizontal plate

    SciTech Connect (OSTI)

    Kang, B.H.; Jaluria, Y.; Tewari, S.S. )

    1990-08-01

    An experimental study of the mixed convective heat transfer from an isolated source of finite thickness, located on a horizontal surface in an externally induced forced flow, has been carried out. This problem is of particular interest in the cooling of electronic components and also in the thermal transport associated with various manufacturing systems, such as ovens and furnaces. The temperature distribution in the flow as well as the surface temperature variation are studied in detail. The dependence of the heat transfer rate on the mixed convection parameter and on the thickness of the heated element or source, particularly in the vicinity of the source, is investigated. The results obtained indicate that the heat transfer rate and fluid flow characteristics vary strongly with the mixed convection variables. The transition from a natural convection dominated flow to a forced convection dominated flow is studied experimentally and the basic characteristics of the two regimes determined. This transition has a strong influence on the temperature of the surface and on the heat transfer rate. As expected, the forced convection dominated flow is seen to be significantly more effective in the cooling of a heat dissipating component than a natural convection dominated flow. The location of the maximum temperature on the module surface, which corresponds to the minimum local heat transfer coefficient, is determined and discussed in terms of the underlying physical mechanisms. The results obtained are also compared with these for an element of negligible thickness and the effect of a significant module thickness on the transport is determined. Several other important aspects of fundamental and applied interest are studied in this investigation.

  10. New ALS Technique Gives Nanoscale Views of Complex Systems

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

    to the formation of the planets and solar system. The potential of SINS is great for battery research, as an understanding of battery chemistry on the mesoscale could provide...

  11. Deep convective parameterization: Some issues (and some solutions?)

    E-Print Network [OSTI]

    Plant, Robert

    are basically an exercise in engineering / tuning fairly bad Deep convective parameterization ­ p.1/4 #12;Aim in engineering / tuning fairly bad The reality is that deep convective parameterizations are basicallyDeep convective parameterization: Some issues (and some solutions?) Bob Plant Department

  12. Convection in Stars Proceedings IAU Symposium No. 239, 2007

    E-Print Network [OSTI]

    Arnett, W. David

    and the geometric parameters in mixing length theory, and the solar Ne abundance problem. Explicit comparisons convection (with nuclear burning). The simulations are run long enough so that a robust statistical state will be made with convective driving of waves, convective zone growth by entrainment, the velocity scale

  13. Convective injection into stratospheric intrusions Cameron R. Homeyer,1

    E-Print Network [OSTI]

    Pan, Laura

    Convective injection into stratospheric intrusions Cameron R. Homeyer,1 Kenneth P. Bowman,1 Laura L, are not entirely understood. This study presents direct observations of moist convection penetrating into stratospheric intrusions. The characteristics of convective injection are shown by using in situ aircraft

  14. Stellar convective cores as dark matter probes

    E-Print Network [OSTI]

    Jordi Casanellas; Isa M. Brandão; Yveline Lebreton

    2015-05-06

    The recent detection of a convective core in a main-sequence solar-type star is used here to test particular models of dark matter (DM) particles, those with masses and scattering cross sections in the range of interest for the DM interpretation of the positive results in several DM direct detection experiments. If DM particles do not effectively self-annihilate after accumulating inside low-mass stars (e.g. in the asymmetric DM scenario) their conduction provides an efficient mechanism of energy transport in the stellar core. For main-sequence stars with masses between 1.1 and 1.3 Msun, this mechanism may lead to the suppression of the inner convective region expected to be present in standard stellar evolution theory. The asteroseismic analysis of the acoustic oscillations of a star can prove the presence/absence of such a convective core, as it was demonstrated for the first time with the Kepler field main-sequence solar-like pulsator, KIC 2009505. Studying this star we found that the asymmetric DM interpretation of the results in the CoGeNT experiment is incompatible with the confirmed presence of a small convective core in KIC 2009505.

  15. The Midlatitude Continental Convective Clouds Experiment (MC3E) sounding network: operations, processing and analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jensen, M. P.; Toto, T.; Troyan, D.; Ciesielski, P. E.; Holdridge, D.; Kyrouac, J.; Schatz, J.; Zhang, Y.; Xie, S.

    2015-01-27

    The Midlatitude Continental Convective Clouds Experiment (MC3E) took place during the spring of 2011 centered in north-central Oklahoma, USA. The main goal of this field campaign was to capture the dynamical and microphysical characteristics of precipitating convective systems in the US Central Plains. A major component of the campaign was a six-site radiosonde array designed to capture the large-scale variability of the atmospheric state with the intent of deriving model forcing data sets. Over the course of the 46-day MC3E campaign, a total of 1362 radiosondes were launched from the enhanced sonde network. This manuscript provides details on the instrumentationmore »used as part of the sounding array, the data processing activities including quality checks and humidity bias corrections and an analysis of the impacts of bias correction and algorithm assumptions on the determination of convective levels and indices. It is found that corrections for known radiosonde humidity biases and assumptions regarding the characteristics of the surface convective parcel result in significant differences in the derived values of convective levels and indices in many soundings. In addition, the impact of including the humidity corrections and quality controls on the thermodynamic profiles that are used in the derivation of a large-scale model forcing data set are investigated. The results show a significant impact on the derived large-scale vertical velocity field illustrating the importance of addressing these humidity biases.« less

  16. The Midlatitude Continental Convective Clouds Experiment (MC3E) sounding network: operations, processing and analysis

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Jensen, M. P.; Toto, T.; Troyan, D.; Ciesielski, P. E.; Holdridge, D.; Kyrouac, J.; Schatz, J.

    2014-09-12

    The Midlatitude Continental Convective Clouds Experiment (MC3E) took place during the spring of 2011 centered in north-central Oklahoma, USA. The main goal of this field campaign was to capture the dynamical and microphysical characteristics of precipitating convective systems in the Central Plains. A major component of the campaign was a 6-site radiosonde array designed to capture the large-scale variability of the atmospheric state with the intent of deriving model forcing datasets. Over the course of the 46 day MC3E campaign, a total of 1362 radiosondes were launched from the enhanced sonde network. This manuscript describes the details of the instrumentationmore »used as part of the sounding array, the data processing activities including quality checks and humidity bias corrections and an analysis of the impacts of bias correction and algorithm assumptions on the determination of convective levels and indices. It is found that corrections for known radiosonde humidity biases and assumptions regarding the characteristics of the surface convective parcel result in significant differences in the derived values of convective levels and indices in many soundings.« less

  17. Buoyancy Effects on the Scaling Characteristics of Atmospheric Boundary Layer Wind Fields in the Mesoscale Range

    E-Print Network [OSTI]

    Kiliyanpilakkil, V P; Ruiz-Columbié, A; Araya, G; Castillo, L; Hirth, B; Burgett, W

    2015-01-01

    We have analyzed long-term wind speed time-series from five field sites up to a height of 300 m from the ground. Structure function-based scaling analysis has revealed that the scaling exponents in the mesoscale regime systematically depend on height. This anomalous behavior is shown to be caused by the buoyancy effects. In the framework of the extended self-similarity, the relative scaling exponents portray quasi-universal behavior.

  18. MESO-SCALE MODELING OF THE INFLUENCE OF INTERGRANULAR GAS BUBBLES ON EFFECTIVE THERMAL CONDUCTIVITY

    SciTech Connect (OSTI)

    Paul C. Millett; Michael Tonks

    2011-06-01

    Using a mesoscale modeling approach, we have investigated how intergranular fission gas bubbles, as observed in high-burnup nuclear fuel, modify the effective thermal conductivity in a polycrystalline material. The calculations reveal that intergranular porosity has a significantly higher resistance to heat transfer compared to randomly-distributed porosity. A model is developed to describe this conductivity reduction that considers an effective grain boundary Kapitza resistance as a function of the fractional coverage of grain boundaries by bubbles.

  19. Convective Heat Transfer Augmentation by Flexible fins in Laminar Channel Pulsating flow

    E-Print Network [OSTI]

    Joshi, Rakshitha U; Bhardwaj, Rajneesh

    2015-01-01

    Fluid-structure interaction (FSI) of thin flexible fins coupled with convective heat transfer has applications in energy harvesting and in understanding functioning of several biological systems. We numerically investigate FSI of the thin flexible fins involving large-scale flow-induced deformation as a potential heat transfer enhancement technique. An in-house, strongly-coupled fluid-structure interaction (FSI) solver is employed in which flow and structure solvers are based on sharp-interface immersed boundary and finite element method, respectively. We consider twin flexible fins in a heated channel with laminar pulsating cross flow. The vortex ring past the fin sweep higher sources of vorticity generated on the channel walls out into the downstream - promoting the mixing of the fluid. The moving fin assists in convective mixing, augmenting convection in bulk and at the walls; and thereby reducing thermal boundary layer thickness and improving heat transfer at the channel walls. The thermal augmentation is...

  20. Macroscale modeling and mesoscale observations of plasma density structures in the polar cap

    SciTech Connect (OSTI)

    Basu, S.; Basu, S.; Sojka, J.J.; Schunk, R.W.; MacKenzie, E.

    1995-04-15

    The seasonal and UT variation of mesoscale structures (10 km - 100 m) in the central polar cap has been obtained from an analysis of 250-MHz intensity scintillation observations made at Thule, Greenland. It has been established earlier that mesoscale structures causing scintillations of satellite signals may develop at the edges of macroscale structures (several hundred km) such as discrete polar cap plasma density enhancements or patches through the gradient drift instability process. As such, the authrs examined the seasonal and UT variation of polar cap patches simulated by using the USU Time Dependent Ionospheric Model (TDIM) under conditions of southward B(sub z). A fairly remarkable similarity is found between the scintillation observations and the model predictions of patch occurrence. For instance, both the patch and scintillation occurrences are minimized during the winter solstice (northern hemisphere) between 0800-1200 UT while also having their largest seasonal intensity between 2000-2400 UT. Little UT dependence of patches and scintillations is seen at equinox with high intensity being observed throughout the day, while during local summer the intensity of macroscale patches and mesoscale irregularities are found to be a minimum at all UT. These results indicate that macroscale features in the polar cap are routinely associated with plasma instabilities giving rise to smaller scale structures and that the specific patch formation mechanism assumed in the simulation is consistent with the observations.

  1. Boundaries of the Peruvian Oxygen Minimum Zone shaped by coherent mesoscale dynamics

    E-Print Network [OSTI]

    Bettencourt, João H; García, Emilio Hernández; Montes, Ivonne; Sudre, Joël; Dewitte, Boris; Paulmier, Aurélien; Garçon, Véronique

    2015-01-01

    Dissolved oxygen in sea water is a major factor affecting marine habitats and biogeochemical cycles. Oceanic zones with oxygen deficits represent significant portions of the area and volume of the oceans and are thought to be expanding. The Peruvian oxygen minimum zone is one of the most pronounced and lies in a region of strong mesoscale activity in the form of vortices and frontal regions, whose effect in the dynamics of the oxygen minimum zone is largely unknown. Here, we study this issue from a modeling approach and a Lagrangian point of view, using a coupled physical-biogeochemical simulation of the Peruvian oxygen minimum zone and finite-size Lyapunov exponent fields to understand the link between mesoscale dynamics and oxygen variations. Our results show that, at depths between 380 and 600 meters, mesoscale structures have a relevant dual role. First, their mean positions and paths delimit and maintain the oxygen minimum zone boundaries. Second, their high frequency fluctuations entrain oxygen across t...

  2. Numerical Investigation of Natural Convection Loss in Cavity-Type Solar Receivers

    E-Print Network [OSTI]

    Numerical Investigation of Natural Convection Loss in Cavity-Type Solar Receivers S-mail: Sawat.Paitoonsurikarn@anu.edu.au Abstract In solar thermal systems, especially for high concentration by various previously proposed empirical models. The Clausing model (1981) shows the closest prediction

  3. Measurements of Snow Crystal Growth Dynamics in a Free-fall Convection Chamber

    E-Print Network [OSTI]

    Libbrecht, Kenneth G.

    Measurements of Snow Crystal Growth Dynamics in a Free-fall Convection Chamber Kenneth G. Libbrecht example of this phenomenon is the formation of snow crystals, which are ice crystals that grow from water vapor in an inert background gas. Although this is a relatively simple physical system, snow crystals

  4. Penetrative internally heated convection in two and three dimensions

    E-Print Network [OSTI]

    Goluskin, David

    2015-01-01

    Convection of an internally heated fluid, confined between top and bottom plates of equal temperature, is studied by direct numerical simulation in two and three dimensions. The unstably stratified upper region drives convection that penetrates into the stably stratified lower region. The fraction of produced heat escaping across the bottom plate, which is one half without convection, initially decreases as convection strengthens. Entering the turbulent regime, this decrease reverses in two dimensions but continues monotonically in three dimensions. The mean fluid temperature, which grows proportionally to the heating rate ($H$) without convection, grows like $H^{4/5}$ when convection is strong in both two and three dimensions. The ratio of the heating rate to the fluid temperature is likened to the Nusselt number of Rayleigh-B\\'enard convection. Simulations are reported for Prandtl numbers between 0.1 and 10 and for Rayleigh numbers (defined in terms of the heating rate) up to $5\\times10^{10}$.

  5. In Situ Decommissioning Sensor Network, Meso-Scale Test Bed - Phase 3 Fluid Injection Test Summary Report

    SciTech Connect (OSTI)

    Serrato, M. G.

    2013-09-27

    The DOE Office of Environmental management (DOE EM) faces the challenge of decommissioning thousands of excess nuclear facilities, many of which are highly contaminated. A number of these excess facilities are massive and robust concrete structures that are suitable for isolating the contained contamination for hundreds of years, and a permanent decommissioning end state option for these facilities is in situ decommissioning (ISD). The ISD option is feasible for a limited, but meaningfull number of DOE contaminated facilities for which there is substantial incremental environmental, safety, and cost benefits versus alternate actions to demolish and excavate the entire facility and transport the rubble to a radioactive waste landfill. A general description of an ISD project encompasses an entombed facility; in some cases limited to the blow-grade portion of a facility. However, monitoring of the ISD structures is needed to demonstrate that the building retains its structural integrity and the contaminants remain entombed within the grout stabilization matrix. The DOE EM Office of Deactivation and Decommissioning and Facility Engineering (EM-13) Program Goal is to develop a monitoring system to demonstrate long-term performance of closed nuclear facilities using the ISD approach. The Savannah River National Laboratory (SRNL) has designed and implemented the In Situ Decommissioning Sensor Network, Meso-Scale Test Bed (ISDSN-MSTB) to address the feasibility of deploying a long-term monitoring system into an ISD closed nuclear facility. The ISDSN-MSTB goal is to demonstrate the feasibility of installing and operating a remote sensor network to assess cementitious material durability, moisture-fluid flow through the cementitious material, and resulting transport potential for contaminate mobility in a decommissioned closed nuclear facility. The original ISDSN-MSTB installation and remote sensor network operation was demonstrated in FY 2011-12 at the ISDSN-MSTB test cube located at the Florida International University Applied Research Center, Miami, FL (FIU-ARC). A follow-on fluid injection test was developed to detect fluid and ion migration in a cementitious material/grouted test cube using a limited number of existing embedded sensor systems. This In Situ Decommissioning Sensor Network, Meso-Scale Test Bed (ISDSN-MSTB) - Phase 3 Fluid Injection Test Summary Report summarizes the test implementation, acquired and processed data, and results from the activated embedded sensor systems used during the fluid injection test. The ISDSN-MSTB Phase 3 Fluid Injection Test was conducted from August 27 through September 6, 2013 at the FIU-ARC ISDSN-MSTB test cube. The fluid injection test activated a portion of the existing embedded sensor systems in the ISDSN-MSTB test cube: Electrical Resistivity Tomography-Thermocouple Sensor Arrays, Advance Tensiometer Sensors, and Fiber Loop Ringdown Optical Sensors. These embedded sensor systems were activated 15 months after initial placement. All sensor systems were remotely operated and data acquisition was completed through the established Sensor Remote Access System (SRAS) hosted on the DOE D&D Knowledge Management Information Tool (D&D DKM-IT) server. The ISDN Phase 3 Fluid Injection Test successfully demonstrated the feasibility of embedding sensor systems to assess moisture-fluid flow and resulting transport potential for contaminate mobility through a cementitious material/grout monolith. The ISDSN embedded sensor systems activated for the fluid injection test highlighted the robustness of the sensor systems and the importance of configuring systems in-depth (i.e., complementary sensors and measurements) to alleviate data acquisition gaps.

  6. Simulating the Transition from Drizzling Marine Stratocumulus to Boundary Layer Cumulus with a Mesoscale Model

    E-Print Network [OSTI]

    Mechem, David B.; Kogan, Yefim L.

    2003-10-01

    variability is analogous to the drizzle-induced cloud breakup produced in large eddy simulation studies. The dynamics of the pure stratocumulus cloud are dictated by the model's subgrid parameterization, while the more convective regime exhibits appreciable...

  7. The annual cycle in equatorial convection and sea surface temperature

    SciTech Connect (OSTI)

    Mitchell, T.P.; Wallace, J.M. (Washington Univ., Seattle (United States) NASA, Goddard Space Flight Center, Greenbelt, MD (United States))

    1992-10-01

    The coupled atmosphere-ocean system in the equatorial eastern Pacific and Atlantic exhibits a distinct annual cycle that is reflected in contrasting conditions at the times of the two equinoxes. The contrasts are so strong that they dominate the annual march of zonally averaged outgoing long wave radiation for the equatorial belt. The March equinox corresponds to the warm season when the equatorial cold tongues in the eastern Pacific and Atlantic area absent. With the onset of summer monsoon convection over Colombia, Central America, and West Africa in May-June, northward surface winds strengthen over the eastern Pacific and Atlantic, the equatorial cold tongues reappear, and the marine convection shifts from the equatorial belt to the intertropical convergence zones (ITCZs) along 8 deg N. On the basis of observational evidence concerning the timing and year-to-year regularity of the surface wind changes during the development of the cold tongues, it is argued that (1) the increase in the northward surface winds in response to the onset of the northern summer monsoon may be instrumental in reestablishing the cold tongues, and (2) positive feedbacks involving both the zonal and meridional wind components contribute to the remarkable robustness of the cold tongue-ITCZs complexes in both oceans. 36 refs.

  8. Convection of a stratified colloidal suspension

    SciTech Connect (OSTI)

    Cherepanov, I. N.; Smorodin, B. L., E-mail: bsmorodin@yandex.ru [Perm National Research University (Russian Federation)

    2013-11-15

    The convection of a colloidal suspension, which is a binary mixture of a carrier medium with an admixture of nanoparticles having a large positive thermal diffusion parameter, has been studied for the case of the heating of a horizontal cell from below and periodic conditions at the vertical boundaries corresponding to the experimental situation of ring channels. Bifurcation diagrams have been constructed for vibrational and monotonic regimes of the convection of the colloidal mixture. The time dependences of the maximum stream function and the stream function at a fixed point of the cell, as well as the spatial distributions of the concentration field of the colloid admixture, have been obtained. It has been shown that a stable regime of traveling waves exists in a certain region of the parameters of the problem (Boltzmann and Rayleigh numbers characterizing the gravitational stratification and intensity of the thermal effect, respectively)

  9. Magnetic flux concentrations from turbulent stratified convection

    E-Print Network [OSTI]

    Käpylä, P J; Kleeorin, N; Käpylä, M J; Rogachevskii, I

    2015-01-01

    (abridged) Context: The mechanisms that cause the formation of sunspots are still unclear. Aims: We study the self-organisation of initially uniform sub-equipartition magnetic fields by highly stratified turbulent convection. Methods: We perform simulations of magnetoconvection in Cartesian domains that are $8.5$-$24$ Mm deep and $34$-$96$ Mm wide. We impose either a vertical or a horizontal uniform magnetic field in a convection-driven turbulent flow. Results: We find that super-equipartition magnetic flux concentrations are formed near the surface with domain depths of $12.5$ and $24$ Mm. The size of the concentrations increases as the box size increases and the largest structures ($20$ Mm horizontally) are obtained in the 24 Mm deep models. The field strength in the concentrations is in the range of $3$-$5$ kG. The concentrations grow approximately linearly in time. The effective magnetic pressure measured in the simulations is positive near the surface and negative in the bulk of the convection zone. Its ...

  10. Convective Dynamo Simulation with a Grand Minimum

    E-Print Network [OSTI]

    Augustson, Kyle; Miesch, Mark; Toomre, Juri

    2015-01-01

    The global-scale dynamo action achieved in a simulation of a Sun-like star rotating at thrice the solar rate is assessed. The 3-D MHD Anelastic Spherical Harmonic (ASH) code, augmented with a viscosity minimization scheme, is employed to capture convection and dynamo processes in this G-type star. The simulation is carried out in a spherical shell that encompasses 3.8 density scale heights of the solar convection zone. It is found that dynamo action with a high degree of time variation occurs, with many periodic polarity reversals occurring roughly every 6.2 years. The magnetic energy also rises and falls with a regular period. The magnetic energy cycles arise from a Lorentz-force feedback on the differential rotation, whereas the processes leading to polarity reversals are more complex, appearing to arise from the interaction of convection with the mean toroidal fields. Moreover, an equatorial migration of toroidal field is found, which is linked to the changing differential rotation, and potentially to a no...

  11. P h y s i c a l O c e a n o g r a p h y D i v i s i o n Role of Mesoscale Eddies on Decadal Variability of the South

    E-Print Network [OSTI]

    P h y s i c a l O c e a n o g r a p h y D i v i s i o n Role of Mesoscale Eddies on Decadal representation of mesoscale eddies in the ocean. Therefore, the impact of mesoscale eddies on climate variability the mesoscale eddies are properly parameterized in CMIP5 models. Our overall goal is to explore the impact

  12. Effects of convection on the mean solar structure

    E-Print Network [OSTI]

    Christensen-Dalsgaard, J

    1996-01-01

    The overall framework for the study of solar convection and oscillations is the spherically symmetric component of solar structure. I discuss those properties of the solar interior which depend on convection and other possible hydrodynamical motion and the increasingly detailed information about the structure which is provided by helioseismic data. The most basic dependence of solar models on convection is the calibration to fix the solar radius. The dominant causes for differences in oscillation frequencies between the Sun and solar models seem to be located near the top of the convection zone. However, there is also evidence for possible weak mixing below the convection zone and perhaps in the solar core. The former, at least, might be induced by penetration of convective motion into the stable layers below.

  13. Dynamic mesoscale model of dipolar fluids via fluctuating hydrodynamics

    SciTech Connect (OSTI)

    Persson, Rasmus A. X.; Chu, Jhih-Wei, E-mail: jwchu@nctu.edu.tw [Institute of Bioinformatics and Systems Biology, National Chiao Tung University, Hsinchu 30068, Taiwan (China); Department of Biological Science and Technology, National Chiao Tung University, Hsinchu 30068, Taiwan (China); Voulgarakis, Nikolaos K. [Department of Mathematics, Washington State University, Richland, Washington 99372 (United States)

    2014-11-07

    Fluctuating hydrodynamics (FHD) is a general framework of mesoscopic modeling and simulation based on conservational laws and constitutive equations of linear and nonlinear responses. However, explicit representation of electrical forces in FHD has yet to appear. In this work, we devised an Ansatz for the dynamics of dipole moment densities that is linked with the Poisson equation of the electrical potential ? in coupling to the other equations of FHD. The resulting ?-FHD equations then serve as a platform for integrating the essential forces, including electrostatics in addition to hydrodynamics, pressure-volume equation of state, surface tension, and solvent-particle interactions that govern the emergent behaviors of molecular systems at an intermediate scale. This unique merit of ?-FHD is illustrated by showing that the water dielectric function and ion hydration free energies in homogeneous and heterogenous systems can be captured accurately via the mesoscopic simulation. Furthermore, we show that the field variables of ?-FHD can be mapped from the trajectory of an all-atom molecular dynamics simulation such that model development and parametrization can be based on the information obtained at a finer-grained scale. With the aforementioned multiscale capabilities and a spatial resolution as high as 5 Å, the ?-FHD equations represent a useful semi-explicit solvent model for the modeling and simulation of complex systems, such as biomolecular machines and nanofluidics.

  14. Nesting large-eddy simulations within mesoscale simulations for wind energy applications

    SciTech Connect (OSTI)

    Lundquist, J K; Mirocha, J D; Chow, F K; Kosovic, B; Lundquist, K A

    2008-09-08

    With increasing demand for more accurate atmospheric simulations for wind turbine micrositing, for operational wind power forecasting, and for more reliable turbine design, simulations of atmospheric flow with resolution of tens of meters or higher are required. These time-dependent large-eddy simulations (LES), which resolve individual atmospheric eddies on length scales smaller than turbine blades and account for complex terrain, are possible with a range of commercial and open-source software, including the Weather Research and Forecasting (WRF) model. In addition to 'local' sources of turbulence within an LES domain, changing weather conditions outside the domain can also affect flow, suggesting that a mesoscale model provide boundary conditions to the large-eddy simulations. Nesting a large-eddy simulation within a mesoscale model requires nuanced representations of turbulence. Our group has improved the Weather and Research Forecasting model's (WRF) LES capability by implementing the Nonlinear Backscatter and Anisotropy (NBA) subfilter stress model following Kosovic (1997) and an explicit filtering and reconstruction technique to compute the Resolvable Subfilter-Scale (RSFS) stresses (following Chow et al, 2005). We have also implemented an immersed boundary method (IBM) in WRF to accommodate complex terrain. These new models improve WRF's LES capabilities over complex terrain and in stable atmospheric conditions. We demonstrate approaches to nesting LES within a mesoscale simulation for farms of wind turbines in hilly regions. Results are sensitive to the nesting method, indicating that care must be taken to provide appropriate boundary conditions, and to allow adequate spin-up of turbulence in the LES domain.

  15. Mesoscale Origin of the Enhanced Cycling-Stability of the Si-Conductive Polymer Anode for Li-ion Batteries

    SciTech Connect (OSTI)

    Gu, Meng; Xiao, Xingcheng; Liu, Gao; Thevuthasan, Suntharampillai; Baer, Donald R.; Zhang, Jiguang; Liu, Jun; Browning, Nigel D.; Wang, Chong M.

    2014-01-14

    Electrode used in lithium-ion battery is invariably a composite of multifunctional components. The performance of the electrode is controlled by the interactive function of all components at mesoscale. Fundamental understanding of mesoscale phenomenon sets the basis for innovative designing of new materials. Here we report the achievement and origin of a significant performance enhancement of electrode for lithium ion batteries based on Si nanoparticles wrapped with conductive polymer. This new material is in marked contrast with conventional material, which exhibit fast capacity fade. In-situ TEM unveils that the enhanced cycling stability of the conductive polymer-Si composite is associated with mesoscale concordant function of Si nanoparticles and the conductive polymer. Reversible accommodation of the volume changes of Si by the conductive polymer allows good electrical contact between all the particles during the cycling process. In contrast, the failure of the conventional Si-electrode is probed to be the inadequate electrical contact.

  16. VOLUME 84, NUMBER 7 P H Y S I C A L R E V I E W L E T T E R S 14 FEBRUARY 2000 Dislocation Patterning: From Micro-to Mesoscale Description

    E-Print Network [OSTI]

    Groma, István

    Patterning: From Micro- to Mesoscale Description I. Groma and B. Bakó Eötvös University, Department the problem on a mesoscale. Numerical results obtained in double slip configu- ration indicate the development to stress that the proposed mesoscale evolu- tion equations are derived from the equations of motion

  17. 3128 VOLUME 11J O U R N A L O F C L I M A T E Mesoscale Disturbance and Ecological Response to Decadal Climatic Variability in the

    E-Print Network [OSTI]

    3128 VOLUME 11J O U R N A L O F C L I M A T E Mesoscale Disturbance and Ecological Response ( 102 km2 ) to mesoscale (104 ­106 km2 ). Climate­disturbance relations are more variable and complex than previously assumed. During the past three centuries, mesoscale outbreaks of the western spruce

  18. Soil Moisture Impacts on Convective Precipitation in Oklahoma 

    E-Print Network [OSTI]

    Ford, Trenton

    2015-07-24

    of the States” instilled in me a lifelong curiosity in Geography. v NOMENCLATURE CAPE Convective Available Potential Energy CIN Convective Inhibition CTP Convective Triggering Potential DDR Directional Difference Ratio DM Dry Moderate DP Dry Polar.... The black line represents the 1-to-1 fit, while the dashed line represents the least squares fit. .………………………..119 Figure 5.3. Boxplots of DDR from each directional difference over dry soil events. The black, dashed line represents the 0 value, by which...

  19. Transport coefficients of off-lattice mesoscale-hydrodynamics simulation techniques

    E-Print Network [OSTI]

    Hiroshi Noguchi; Gerhard Gompper

    2008-04-14

    The viscosity and self-diffusion constant of particle-based mesoscale hydrodynamic methods, multi-particle collision dynamics (MPC) and dissipative particle dynamics (DPD), are investigated, both with and without angular-momentum conservation. Analytical results are derived for fluids with an ideal-gas equation of state and a finite-time-step dynamics, and compared with simulation data. In particular, the viscosity is derived in a general form for all variants of the MPC method. In general, very good agreement between theory and simulations is obtained.

  20. Interactions between cumulus convection and its environment as...

    Office of Scientific and Technical Information (OSTI)

    Convective Clouds Experiment (MC3E) in central Oklahoma. Distinct large-scale structures and diabatic heating and drying profiles are presented for cases of weaker and...

  1. Objectives of Work Packages WP1: Thermal convection

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    MAGMA Objectives of Work Packages WP1: Thermal convection Coordinator: O. Cadek · To enhance air-pollution assessment in the urban environment · To study the solar radiation impact

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

    E-Print Network [OSTI]

    Gadgil, Ashok; Bauman, Fred; Kammerud, Ronald

    2008-01-01

    CONVECTION IN PASSIVE SOLAR BUILDINGS: ANALYSIS AND RESULTSCONVECTION IN PASSIVE SOLAR BUILDINGS: EXPERIMENTS, ANALYSISin a direct gain passive solar building; this is described

  3. Convectively generated zonal jets by thunderstorms on Jupiter

    E-Print Network [OSTI]

    Zhang, Xi Arthur; Showman, Adam

    2011-01-01

    formation of equatorial jets in freely decaying shallowof moist convection with zonal jets on Jupiter and Saturn,Generation of equatorial jets by large-scale latent heating

  4. Development of fine-resolution analyses and expanded large-scale...

    Office of Scientific and Technical Information (OSTI)

    the impact of the grid-scale and subgrid-scale dynamic components on simulated precipitation and cloud fields associated with a mesoscale convective system. It is found that...

  5. Numerical simulation of the 16-19 October 1994 southeast Texas heavy rain event: precipitation results and diagnosis of the lifting mechanism 

    E-Print Network [OSTI]

    Petroski, Thomas John

    2000-01-01

    During the period 16-19 October 1994, a mesoscale convective system (MCS) developed within a weakly forced large-scale environment over relatively flat terrain. This resulted in extreme rainfall totals and subsequent ...

  6. Mesoscale Equipartition of kinetic energy in Quantum Turbulence

    E-Print Network [OSTI]

    Salort, Julien; Lévêque, Emmanuel; 10.1209/0295-5075/94/24001

    2012-01-01

    The turbulence of superfluid helium is investigated numerically at finite temperature. Direct numerical simulations are performed with a "truncated HVBK" model, which combines the continuous description of the Hall-Vinen-Bekeravich-Khalatnikov equations with the additional constraint that this continuous description cannot extend beyond a quantum length scale associated with the mean spacing between individual superfluid vortices. A good agreement is found with experimental measurements of the vortex density. Besides, by varying the turbulence intensity only, it is observed that the inter-vortex spacing varies with the Reynolds number as $Re^{-3/4}$, like the viscous length scale in classical turbulence. In the high temperature limit, Kolmogorov's inertial cascade is recovered, as expected from previous numerical and experimental studies. As the temperature decreases, the inertial cascade remains present at large scales while, at small scales, the system evolves towards a statistical equipartition of kinetic ...

  7. What Goes Up Must Come Down: The Lifecycle of Convective Clouds (492nd Brookhaven Lecture)

    SciTech Connect (OSTI)

    Jensen, Michael [BNL Environmental Sciences

    2014-02-19

    Some clouds look like cotton balls and others like anvils. Some bring rain, some snow and sleet, and others, just shade. But, whether big and billowy or dark and stormy, clouds affect far more than the weather each day. Armed with measurements of clouds’ updrafts and downdrafts—which resemble airflow in a convection oven—and many other atmospheric interactions, scientists from Brookhaven Lab and other institutions around the world are developing models that are crucial for understanding Earth’s climate and forecasting future climate change. During his lecture, Dr. Jensen provides an overview of the importance of clouds in the Earth’s climate system before explaining how convective clouds form, grow, and dissipate. His discussion includes findings from the Midlatitude Continental Convective Clouds Experiment (MC3E), a major collaborative experiment between U.S. Department of Energy (DOE) and NASA scientists to document precipitation, clouds, winds, and moisture in 3-D for a holistic view of convective clouds and their environment.

  8. Natural convection airflow measurement and theory

    SciTech Connect (OSTI)

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

    1984-01-01

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

  9. Atmospheric Radiation Measurement Convective and Orographically Induced

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O DBiomass and BiofuelsPhysicist47 Industrial1Convective and

  10. ARM - Evaluation Product - Convective Vertical Velocity

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments? WeDatastreamstps DocumentationAtlanticENA Contacts ENA RelatedProductsCalibrated KAZRProductsConvective

  11. A New Model for Mixing By Double-Diffusive Convection (Semi-Convection). III. Thermal and Compositional Transport Through Non-Layered ODDC

    E-Print Network [OSTI]

    Moll, Ryan; Stellmach, Stephan

    2015-01-01

    Oscillatory double-diffusive convection (ODDC) (also known as semi- convection) refers to a type of double diffusive instability that occurs in regions of planetary and stellar interiors which have a destabilizing thermal stratification and a stabilizing mean molecular weight stratification. In this series of papers, we use an extensive suite of three-dimensional (3D) numerical simulations to quantify the transport of heat and chemical species by ODDC. Rosenblum et al. (2011) first showed that ODDC can either spontaneously form layers, which significantly enhance the transport of heat and chemical species compared to mi- croscopic transport, or remain in a state dominated by large scale gravity waves, in which there is a more modest enhancement of the turbulent transport rates. Subsequent studies in this series have focused on identifying under what condi- tions layers form (Mirouh et al. 2012), and quantifying transport through layered systems (Wood et al. 2013). Here we proceed to characterize transport thr...

  12. Coherent neutron scattering and collective dynamics on mesoscale

    SciTech Connect (OSTI)

    Novikov, Vladimir [ORNL; Schweizer, Kenneth S [ORNL; Sokolov, Alexei P [ORNL

    2013-01-01

    By combining, and modestly extending, a variety of theoretical concepts for the dynamics of liquids in the supercooled regime, we formulate a simple analytic model for the temperature and wavevector dependent collective density fluctuation relaxation time that is measurable using coherent dynamic neutron scattering. Comparison with experiments on the ionic glass-forming liquid Ca K NO3 in the lightly supercooled regime suggests the model captures the key physics in both the local cage and mesoscopic regimes, including the unusual wavevector dependence of the collective structural relaxation time. The model is consistent with the idea that the decoupling between diffusion and viscosity is reflected in a different temperature dependence of the collective relaxation time at intermediate wavevectors and near the main (cage) peak of the static structure factor. More generally, our analysis provides support for the ideas that decoupling information and growing dynamic length scales can be at least qualitatively deduced by analyzing the collective relaxation time as a function of temperature and wavevector, and that there is a strong link between dynamic heterogeneity phenomena at the single and many particle level. Though very simple, the model can be applied to other systems, such as molecular liquids.

  13. Mesoscale computational studies of membrane bilayer remodeling by curvature-inducing proteins

    E-Print Network [OSTI]

    N. Ramakrishnan; P. B. Sunil Kumar; Ravi Radhakrishnan

    2015-10-16

    Biological membranes constitute boundaries of cells and cell organelles. Physico-chemical mechanisms at the atomic scale are dictated by protein-lipid interaction strength, lipid composition, lipid distribution in the vicinity of the protein, shape and amino acid composition of the protein, and its amino acid contents. The specificity of molecular interactions together with the cooperativity of multiple proteins induce and stabilize complex membrane shapes at the mesoscale. These shapes span a wide spectrum ranging from the spherical plasma membrane to the complex cisternae of the Golgi apparatus. Mapping the relation between the protein-induced deformations at the molecular scale and the resulting mesoscale morphologies is key to bridging cellular experiments across the various length scales. In this review, we focus on the theoretical and computational methods used to understand the phenomenology underlying protein-driven membrane remodeling. The suite of methods discussed here can be tailored to applications in specific cellular settings such as endocytosis during cargo trafficking and tubulation of filopodial structures in migrating cells, which makes these methods a powerful complement to experimental studies.

  14. Air convection noise of pencil-beam interferometer for long trace profiler

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.; Irick, Steve C.; MacDowell, Alastair A.; McKinney, Wayne R.; Takacs, Peter Z.

    2006-01-01

    Air Convection Noise of Pencil-beam Interferometer for Longwe investigate the effect of air convection on laser-beamshown that the NPD spectra due to air convection have a very

  15. Design and fabrication of a meso-scale stirling engine and combustor.

    SciTech Connect (OSTI)

    Echekki, Tarek (Sandia National Laboratories, Livermore, CA); Haroldsen, Brent L. (Sandia National Laboratories, Livermore, CA); Krafcik, Karen L. (Sandia National Laboratories, Livermore, CA); Morales, Alfredo Martin; Mills, Bernice E.; Liu, Shiling; Lee, Jeremiah C. (Sandia National Laboratories, Livermore, CA); Karpetis, Adionos N. (Sandia National Laboratories, Livermore, CA); Chen, Jacqueline H. (Sandia National Laboratories, Livermore, CA); Ceremuga, Joseph T. (Sandia National Laboratories, Livermore, CA); Raber, Thomas N.; Hekmuuaty, Michelle A.

    2005-05-01

    Power sources capable of supplying tens of watts are needed for a wide variety of applications including portable electronics, sensors, micro aerial vehicles, and mini-robotics systems. The utility of these devices is often limited by the energy and power density capabilities of batteries. A small combustion engine using liquid hydrocarbon fuel could potentially increase both power and energy density by an order of magnitude or more. This report describes initial development work on a meso-scale external combustion engine based on the Stirling cycle. Although other engine designs perform better at macro-scales, we believe the Stirling engine cycle is better suited to small-scale applications. The ideal Stirling cycle requires efficient heat transfer. Consequently, unlike other thermodynamic cycles, the high heat transfer rates that are inherent with miniature devices are an advantage for the Stirling cycle. Furthermore, since the Stirling engine uses external combustion, the combustor and engine can be scaled and optimized semi-independently. Continuous combustion minimizes issues with flame initiation and propagation. It also allows consideration of a variety of techniques to promote combustion that would be difficult in a miniature internal combustion engine. The project included design and fabrication of both the engine and the combustor. Two engine designs were developed. The first used a cylindrical piston design fabricated with conventional machining processes. The second design, based on the Wankel rotor geometry, was fabricated by through-mold electroforming of nickel in SU8 and LIGA micromolds. These technologies provided the requisite precision and tight tolerances needed for efficient micro-engine operation. Electroformed nickel is ideal for micro-engine applications because of its high strength and ductility. A rotary geometry was chosen because its planar geometry was more compatible with the fabrication process. SU8 lithography provided rapid prototypes to verify the design. A final high precision engine was created via LIGA. The micro-combustor was based on an excess enthalpy concept. Development of a micro-combustor included both modeling and experiments. We developed a suite of simulation tools both in support of the design of the prototype combustors, and to investigate more fundamental aspects of combustion at small scales. Issues of heat management and integration with the micro-scale Stirling engine were pursued using CFD simulations. We found that by choice of the operating conditions and channel dimensions energy conversion occurs by catalysis-dominated or catalysis-then-homogeneous phase combustion. The purpose of the experimental effort in micro-combustion was to study the feasibility and explore the design parameters of excess enthalpy combustors. The efforts were guided by the necessity for a practical device that could be implemented in a miniature power generator, or as a stand-alone device used for heat generation. Several devices were fabricated and successfully tested using methane as the fuel.

  16. CONVECTIVE STABILITY OF GALAXY-CLUSTER PLASMAS Benjamin D. Chandran

    E-Print Network [OSTI]

    Chandran, Ben

    criterion by causing heat to diffuse primarily along magnetic field lines. We extend earlier analyses a cluster's age. In the cooling flow model, plasma heating is neglected, and the rate at which plasma cools nuclei and cosmic rays drive convection in galaxy-cluster plasmas and that convection heats cluster cores

  17. Toward the Long-range Prediction of Severe Convective Windstorms

    E-Print Network [OSTI]

    Kuligowski, Bob

    Toward the Long-range Prediction of Severe Convective Windstorms Ken Pryor Department review pertaining to severe convective windstorm (SCW) structure and evolution. · Identify potential for the development of a long-range SCW prediction technique. #12;Background · Severe windstorms resulting from large

  18. ON THE INTERACTION BETWEEN CONVECTION AND MAGNETIC FIELDS Fausto Cattaneo

    E-Print Network [OSTI]

    Emonet, Thierry

    found in these different regimes are described and analyzed. Subject headings: convection -- Sun: magnetic fields -- Sun: photosphere 1. INTRODUCTION Magnetic activity is exhibited by late-type stars with deep convective envelopes, but the fine structure of the magnetic field can only be detected on the Sun

  19. Accepted Manuscript Simulations of stellar convection with CO5BOLD

    E-Print Network [OSTI]

    Wedemeyer-Böhm, Sven

    ­ the top of the deep-reaching solar convection zone. Convection plays a role for the thermal structure of the solar interior and the dynamo acting there, for the stratification of the photosphere, where most stratification leads to completely dif- ferent conditions in the interior, the photosphere, and the corona

  20. Characterizing the convective velocity fields in massive stars

    SciTech Connect (OSTI)

    Chatzopoulos, Emmanouil; Graziani, Carlo; Couch, Sean M., E-mail: manolis@astro.as.utexas.edu [Department of Astronomy and Astrophysics, Flash Center for Computational Science, University of Chicago, Chicago, IL 60637 (United States)

    2014-11-01

    We apply the mathematical formalism of vector spherical harmonics decomposition to convective stellar velocity fields from multidimensional hydrodynamics simulations and show that the resulting power spectra furnish a robust and stable statistical description of stellar convective turbulence. Analysis of the power spectra helps identify key physical parameters of the convective process such as the dominant scale of the turbulent motions that influence the structure of massive evolved pre-supernova stars. We introduce the numerical method that can be used to calculate vector spherical harmonics power spectra from two-dimensional (2D) and three-dimensional (3D) convective shell simulation data. Using this method we study the properties of oxygen shell burning and convection for a 15 M {sub ?} star simulated by the hydrodynamics code FLASH in 2D and 3D. We discuss the importance of realistic initial conditions to achieving successful core-collapse supernova explosions in multidimensional simulations. We show that the calculated power spectra can be used to generate realizations of the velocity fields of presupernova convective shells. We find that the slope of the solenoidal mode power spectrum remains mostly constant throughout the evolution of convection in the oxygen shell in both 2D and 3D simulations. We also find that the characteristic radial scales of the convective elements are smaller in 3D than in 2D, while the angular scales are larger in 3D.