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  1. Vanuatu: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Country Profile Name Vanuatu Population 243,304 GDP 743,000,000 Energy Consumption 0.00 Quadrillion Btu 2-letter ISO code VU 3-letter ISO code VUT Numeric ISO...

  2. wake data

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

    wake data - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear Energy

  3. Coalescing Wind Turbine Wakes

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

    Lee, S.; Churchfield, M.; Sirnivas, S.; Moriarty, P.; Nielsen, F. G.; Skaare, B.; Byklum, E.

    2015-06-18

    A team of researchers from the National Renewable Energy Laboratory and Statoil used large-eddy simulations to numerically investigate the merging wakes from upstream offshore wind turbines. Merging wakes are typical phenomena in wind farm flows in which neighboring turbine wakes consolidate to form complex flow patterns that are as yet not well understood. In the present study, three 6-MW turbines in a row were subjected to a neutrally stable atmospheric boundary layer flow. As a result, the wake from the farthest upstream turbine conjoined the downstream wake, which significantly altered the subsequent velocity deficit structures, turbulence intensity, and the globalmore » meandering behavior. The complexity increased even more when the combined wakes from the two upstream turbines mixed with the wake generated by the last turbine, thereby forming a "triplet" structure. Although the influence of the wake generated by the first turbine decayed with downstream distance, the mutated wakes from the second turbine continued to influence the downstream wake. Two mirror-image angles of wind directions that yielded partial wakes impinging on the downstream turbines yielded asymmetric wake profiles that could be attributed to the changing flow directions in the rotor plane induced by the Coriolis force. In conclusion, the turbine wakes persisted for extended distances in the present study, which is a result of low aerodynamic surface roughness typically found in offshore conditions« less

  4. Coalescing Wind Turbine Wakes

    SciTech Connect (OSTI)

    Lee, S.; Churchfield, M.; Sirnivas, S.; Moriarty, P.; Nielsen, F. G.; Skaare, B.; Byklum, E.

    2015-06-18

    A team of researchers from the National Renewable Energy Laboratory and Statoil used large-eddy simulations to numerically investigate the merging wakes from upstream offshore wind turbines. Merging wakes are typical phenomena in wind farm flows in which neighboring turbine wakes consolidate to form complex flow patterns that are as yet not well understood. In the present study, three 6-MW turbines in a row were subjected to a neutrally stable atmospheric boundary layer flow. As a result, the wake from the farthest upstream turbine conjoined the downstream wake, which significantly altered the subsequent velocity deficit structures, turbulence intensity, and the global meandering behavior. The complexity increased even more when the combined wakes from the two upstream turbines mixed with the wake generated by the last turbine, thereby forming a "triplet" structure. Although the influence of the wake generated by the first turbine decayed with downstream distance, the mutated wakes from the second turbine continued to influence the downstream wake. Two mirror-image angles of wind directions that yielded partial wakes impinging on the downstream turbines yielded asymmetric wake profiles that could be attributed to the changing flow directions in the rotor plane induced by the Coriolis force. In conclusion, the turbine wakes persisted for extended distances in the present study, which is a result of low aerodynamic surface roughness typically found in offshore conditions

  5. Spectral coherence in windturbine wakes

    SciTech Connect (OSTI)

    Hojstrup, J.

    1996-12-31

    This paper describes an experiment at a Danish wind farm to investigate the lateral and vertical coherences in the nonequilibrium turbulence of a wind turbine wake. Two meteorological masts were instrumented for measuring profiles of mean speed, turbulence, and temperature. Results are provided graphically for turbulence intensities, velocity spectra, lateral coherence, and vertical coherence. The turbulence was somewhat influenced by the wake, or possibly from aggregated wakes further upstream, even at 14.5 diameters. Lateral coherence (separation 5m) seemed to be unaffected by the wake at 7.5 diameters, but the flow was less coherent in the near wake. The wake appeared to have little influence on vertical coherence (separation 13m). Simple, conventional models for coherence appeared to be adequate descriptions for wake turbulence except for the near wake situation. 3 refs., 7 figs., 1 tab.

  6. Vietnam National Coal Mineral Industries Group Vinacomin | Open...

    Open Energy Info (EERE)

    National Coal Mineral Industries Group Vinacomin Jump to: navigation, search Name: Vietnam National Coal-Mineral Industries Group (Vinacomin) Place: Vietnam Product: Vietnam-based...

  7. SNL Wake Imaging System Solves Wind Turbine Wake Formation Mysteries |

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

    Department of Energy SNL Wake Imaging System Solves Wind Turbine Wake Formation Mysteries SNL Wake Imaging System Solves Wind Turbine Wake Formation Mysteries May 18, 2015 - 4:20pm Addthis Illustration showing a utility-scale wind turbine in a field. A square brown steel shed behind the base of the turbine's tower houses the laser that emits a laser light sheet (illustrated by a green triangle) that travels from the shed to above the turbine downwind of the turbine. A white van parked

  8. Sandia Wake-Imaging System

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

    Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs ... Sandia Wake-Imaging System HomeTag:Sandia ...

  9. Wind farm array wake losses

    SciTech Connect (OSTI)

    Baker, R.W.; McCarthy, E.F.

    1997-12-31

    A wind turbine wake study was conducted in the summer of 1987 at an Altamont Pass wind electric generating facility. The wind speed deficits, turbulence, and power deficits from an array consisting of several rows of wind turbines is discussed. A total of nine different test configurations were evaluated for a downwind spacing ranging from 7 rotor diameters (RD) to 34 RD and a cross wind spacing of 1.3 RD and 2.7 RD. Wake power deficits of 15% were measured at 16 RD and power losses of a few percent were even measurable at 27 RD for the closer cross wind spacing. For several rows of turbines separated by 7-9 RD the wake zones overlapped and formed compound wakes with higher velocity deficits. The wind speed and direction turbulence in the wake was much higher than the ambient turbulence. The results from this study are compared to the findings from other similar field measurements.

  10. Wake Control System Based on Wake Tracking - Energy Innovation Portal

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

    Wind Energy Wind Energy Find More Like This Return to Search Wake Control System Based on Wake Tracking National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary There is a growing interest in the design of wind plant control systems to coordinate the controls of individual turbines to achieve improvements in the overall wind plant performance, such as total power production. Currently, individual turbine controls are adjusted to improve the total

  11. Eyes Witness Report on South Vietnam

    ScienceCinema (OSTI)

    None

    2011-04-25

    Mons. Nielson, conseiller des Etats Unis auprès de L'ONU, apporte son témoignage et exprime son opinion quand à la guerre du Vietnam (Sud)

  12. Vietnam-USAID Country Report | Open Energy Information

    Open Energy Info (EERE)

    deployment programs, Pathways analysis Resource Type: Publications Website: usaid.eco-asia.orgprogramscdcpreportsIdeas-to-ActionannexesAnnex Country: Vietnam UN...

  13. Attachment L-7b Vietnam Design Requirements Document is an Official

    National Nuclear Security Administration (NNSA)

    b Vietnam Design Requirements Document is an Official Use Only document please see Section ... The Government considers the Vietnam Design Requirements Document, Attachment L-7b an ...

  14. U.S.-Vietnam Climate Change Working Group | Open Energy Information

    Open Energy Info (EERE)

    -Vietnam Climate Change Working Group Jump to: navigation, search Name U.S.-Vietnam Climate Change Working Group AgencyCompany Organization United States Geological Survey,...

  15. Advancing Development and Greenhouse Gas Reductions in Vietnams...

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

    ... Reductions in Vietnam's Wind Sector EXECUTIVE SUMMARY Clean energy development is a key component of Vietnam's Green Growth Strategy, which establishes a target to reduce ...

  16. Vietnam-IISD NAMA Support | Open Energy Information

    Open Energy Info (EERE)

    Name Vietnam-IISDNAMA Support AgencyCompany Organization International Institute for Sustainable Development (IISD) Sector Climate Topics Background analysis, Low emission...

  17. Forestry and Poverty Data in Vietnam: Status, Gaps, and Potential...

    Open Energy Info (EERE)

    Type: Dataset, Publications Website: recoftc.orgsitefileadmindocspublicationsTheGreyZone2009Forest Country: Vietnam UN Region: South-Eastern Asia Coordinates:...

  18. Vietnam-Danish Government Sector Programmes | Open Energy Information

    Open Energy Info (EERE)

    Low emission development planning, -LEDS, Policiesdeployment programs Program End 2012 Country Vietnam South-Eastern Asia References Denmark1 Promoting wind energy in...

  19. Vietnam-Renewable Energy Action Plan | Open Energy Information

    Open Energy Info (EERE)

    Renewable Energy Action Plan Jump to: navigation, search Name Vietnam-Renewable Energy Action Plan AgencyCompany Organization World Bank Sector Energy Focus Area Renewable Energy...

  20. Vietnam-UNEP Risoe-Technology Needs Assessment Program | Open...

    Open Energy Info (EERE)

    UNEP Risoe-Technology Needs Assessment Program Jump to: navigation, search Name Vietnam-UNEP Risoe-Technology Needs Assessment Program AgencyCompany Organization UNEP-Risoe...

  1. Impacts of Climate Change on Agriculture and Adaptation in Vietnam...

    Open Energy Info (EERE)

    Climate Change on Agriculture and Adaptation in Vietnam Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Impacts of Climate Change on Agriculture and Adaptation in...

  2. Vietnam-Sub National Planning for Climate Change (cities, states...

    Open Energy Info (EERE)

    Climate Change (cities, states, districts) Jump to: navigation, search Name Vietnam-Sub National Planning for Climate Change (cities, states, districts) AgencyCompany...

  3. Forest Tenure Reform in Vietnam | Open Energy Information

    Open Energy Info (EERE)

    Land Focus Area Forestry Topics Resource assessment, Background analysis Resource Type Lessons learnedbest practices Website http:recoftc.orgsitefilead Country Vietnam UN...

  4. DIELECTRIC WAKE FIELD RESONATOR ACCELERATOR MODULE

    SciTech Connect (OSTI)

    Hirshfield, Jay L.

    2013-11-06

    Results are presented from experiments, and numerical analysis of wake fields set up by electron bunches passing through a cylindrical or rectangular dielectric-lined structure. These bunches excite many TM-modes, with Ez components of the wake fields sharply localized on the axis of the structure periodically behind the bunches. The experiment with the cylindrical structure, carried out at ATF Brookhaven National Laboratory, used up to three 50 MeV bunches spaced by one wake field period (21 cm) to study the superposition of wake fields by measuring the energy loss of each bunch after it passed through the 53-cm long dielectric element. The millimeter-wave spectrum of radiation excited by the passage of bunches is also studied. Numerical analysis was aimed not only to simulate the behavior of our device, but in general to predict dielectric wake field accelerator performance. It is shown that one needs to match the radius of the cylindrical dielectric channel with the bunch longitudinal rms-length to achieve optimal performance.

  5. The Influence of Rotor Blade Design on Wake Development

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

    Influence of Rotor Blade Design on Wake Development - Sandia Energy Energy Search Icon ... Twitter Google + Vimeo GovDelivery SlideShare The Influence of Rotor Blade Design on Wake ...

  6. Sandia Energy - Developing a Fast-Running Turbine Wake Model

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

    Developing a Fast-Running Turbine Wake Model Home Renewable Energy Energy Water Power News News & Events Developing a Fast-Running Turbine Wake Model Previous Next Developing a...

  7. Active Wake Redirection Control to Improve Energy Yield (Poster)

    SciTech Connect (OSTI)

    Churchfield, M. J.; Fleming, P.; DeGeorge, E.; Bulder, B; White, S. M.

    2014-10-01

    Wake effects can dramatically reduce the efficiency of waked turbines relative to the unwaked turbines. Wakes can be deflected, or 'redirected,' by applying yaw misalignment to the turbines. Yaw misalignment causes part of the rotor thrust vector to be pointed in the cross-stream direction, deflecting the flow and the wake. Yaw misalignment reduces power production, but the global increase in wind plant power due to decreased wake effect creates a net increase in power production. It is also a fairly simple control idea to implement at existing or new wind plants. We performed high-fidelity computational fluid dynamics simulations of the wake flow of the proposed Fishermen's Atlantic City Windfarm (FACW) that predict that under certain waking conditions, wake redirection can increase plant efficiency by 10%. This means that by applying wake redirection control, for a given watersheet area, a wind plant can either produce more power, or the same amount of power can be produced with a smaller watersheet area. With the power increase may come increased loads, though, due to the yaw misalignment. If misalignment is applied properly, or if layered with individual blade pitch control, though, the load increase can be mitigated. In this talk we will discuss the concept of wake redirection through yaw misalignment and present our CFD results of the FACW project. We will also discuss the implications of wake redirection control on annual energy production, and finally we will discuss plans to implement wake redirection control at FACW when it is operational.

  8. Dissipation of turbulence in the wake of a wind turbine

    SciTech Connect (OSTI)

    Lundquist, J. K.; Bariteau, L.

    2014-11-06

    The wake of a wind turbine is characterized by increased turbulence and decreased wind speed. Turbines are generally deployed in large groups in wind farms, and so the behaviour of an individual wake as it merges with other wakes and propagates downwind is critical in assessing wind-farm power production. This evolution depends on the rate of turbulence dissipation in the wind-turbine wake, which has not been previously quantified in field-scale measurements. In situ measurements of winds and turbulence dissipation from the wake region of a multi-MW turbine were collected using a tethered lifting system (TLS) carrying a payload of high-rate turbulence probes. Ambient flow measurements were provided from sonic anemometers on a meteorological tower located near the turbine. Good agreement between the tower measurements and the TLS measurements was established for a case without a wind-turbine wake. When an operating wind turbine is located between the tower and the TLS so that the wake propagates to the TLS, the TLS measures dissipation rates one to two orders of magnitude higher in the wake than outside of the wake. These data, collected between two and three rotor diameters D downwind of the turbine, document the significant enhancement of turbulent kinetic energy dissipation rate within the wind-turbine wake. These wake measurements suggest that it may be useful to pursue modelling approaches that account for enhanced dissipation. Furthermore. comparisons of wake and non-wake dissipation rates to mean wind speed, wind-speed variance, and turbulence intensity are presented to facilitate the inclusion of these measurements in wake modelling schemes.

  9. Dissipation of turbulence in the wake of a wind turbine

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

    Lundquist, J. K.; Bariteau, L.

    2014-11-06

    The wake of a wind turbine is characterized by increased turbulence and decreased wind speed. Turbines are generally deployed in large groups in wind farms, and so the behaviour of an individual wake as it merges with other wakes and propagates downwind is critical in assessing wind-farm power production. This evolution depends on the rate of turbulence dissipation in the wind-turbine wake, which has not been previously quantified in field-scale measurements. In situ measurements of winds and turbulence dissipation from the wake region of a multi-MW turbine were collected using a tethered lifting system (TLS) carrying a payload of high-ratemore » turbulence probes. Ambient flow measurements were provided from sonic anemometers on a meteorological tower located near the turbine. Good agreement between the tower measurements and the TLS measurements was established for a case without a wind-turbine wake. When an operating wind turbine is located between the tower and the TLS so that the wake propagates to the TLS, the TLS measures dissipation rates one to two orders of magnitude higher in the wake than outside of the wake. These data, collected between two and three rotor diameters D downwind of the turbine, document the significant enhancement of turbulent kinetic energy dissipation rate within the wind-turbine wake. These wake measurements suggest that it may be useful to pursue modelling approaches that account for enhanced dissipation. Furthermore. comparisons of wake and non-wake dissipation rates to mean wind speed, wind-speed variance, and turbulence intensity are presented to facilitate the inclusion of these measurements in wake modelling schemes.« less

  10. Proposed Training Plan to Improve Building Energy Efficiency in Vietnam

    SciTech Connect (OSTI)

    Yu, Sha; Evans, Meredydd

    2013-01-01

    Vietnam has experienced fast growth in energy consumption in the past decade, with annual growth rate of over 12 percent. This is accompanied by the fast increase in commercial energy use, driven by rapid industrialization, expansion of motorized transport, and increasing energy use in residential and commercial buildings. Meanwhile, Vietnam is experiencing rapid urbanization at a rate of 3.4 percent per year; and the majority of the growth centered in and near major cities such as Hanoi and Ho Chi Minh City. This has resulted in a construction boom in Vietnam.

  11. Wake fields in SLAC Linac Collimators

    SciTech Connect (OSTI)

    Novokhatski, Alexander; Decker, F. -J.; Smith, H.; Sullivan, M.

    2014-12-02

    When a beam travels near collimator jaws, it gets an energy loss and a transverse kick due to the backreaction of the beam field diffracted from the jaws. The effect becomes very important for an intense short bunch when a tight collimation of the background beam halo is required. In the Linac Coherent Light Source at SLAC a collimation system is used to protect the undulators from radiation due to particles in the beam halo. The halo is most likely formed from gun dark current or dark current in some of the accelerating sections. However, collimators are also responsible for the generation of wake fields. The wake field effect from the collimators not only brings an additional energy jitter and change in the trajectory of the beam, but it also rotates the beam on the phase plane, which consequently leads to a degradation of the performance of the Free Electron Laser at the Linac Coherent Light Source. In this paper, we describe a model of the wake field radiation in the SLAC linac collimators. We use the results of a numerical simulation to illustrate the model. Based on the model, we derive simple formulas for the bunch energy loss and the average kick. In addition, we also present results from experimental measurements that confirm our model.

  12. Vietnam-Nordic Partnership Initiative | Open Energy Information

    Open Energy Info (EERE)

    can be matched with up-scaled host country mitigation action through two programs in Peru and Vietnam. The NPI program in Peru will focus on exploring possibilities to lower CO2...

  13. Flow visualization study of the MOD-2 wind turbine wake

    SciTech Connect (OSTI)

    Liu H.T.; Waite, J.W.; Hiester, T.R.; Tacheron, P.H.; Srnsky, R.A.

    1983-06-01

    The specific objectives of the study reported were: to determine the geometry of the MOD-2 wind turbine wake in terms of wake height and width as a function of downstream distance under two conditions of atmospheric stability; to estimate the mean velocity deficit at several downstream stations in the turbine wake; and to investigate the behavior of the rotor-generated vortices, particularly their configuration and persistence. The background of the wake problem is briefly examined, including a discussion of the critical issues that the flow visualization study addresses. Experimental techniques and data analysis methods are described in detail. (LEW)

  14. Virtual LIDAR Model Helps Researchers Plan for Wake Steering...

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

    Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 ... Facility to investigate the use of wind turbine yaw control to direct wakes, a promising ...

  15. Virtual LIDAR model helps researchers plan for the Wake Steering...

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

    Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 ... Facility to investigate the use of wind turbine yaw control to direct wakes, a promising ...

  16. Visualizing Wind Farm Wake Losses using SCADA Data

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

    Continuous Reliability Enhancement for Wind Visualizing Wind Farm Wake Losses using SCADA ... the Department of Energy's Continuous Reliability Enhancement for Wind (CREW) project. ...

  17. Sandia Energy - Post-Processing and Analysis of Wake Measurements...

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

    Post-Processing and Analysis of Wake Measurements Around a Scaled Turbine Home Renewable Energy Energy Water Power Partnership News News & Events Post-Processing and Analysis of...

  18. Forest Carbon Partnership Facility | Open Energy Information

    Open Energy Info (EERE)

    Madagascar, Mexico, Moldova, Mozambique, Nepal, Nicaragua, Panama, Papua New Guinea, Paraguay, Peru, Republic of the Congo, Suriname, Tanzania, Thailand, Uganda, Vanuatu, Vietnam...

  19. Geometrical Wake of a Smooth Flat Collimator

    SciTech Connect (OSTI)

    Stupakov, G.V.; /SLAC

    2011-09-09

    A transverse geometrical wake generated by a beam passing through a smooth flat collimator with a gradually varying gap between the upper and lower walls is considered. Based on generalization of the approach recently developed for a smooth circular taper we reduce the electromagnetic problem of the impedance calculation to the solution of two much simpler static problems - a magnetostatic and an electrostatic ones. The solution shows that in the limit of not very large frequencies, the impedance increases with the ratio h/d where h is the width and d is the distance between the collimating jaws. Numerical results are presented for the NLC Post Linac collimator.

  20. Thermal wake/vessel detection technique

    DOE Patents [OSTI]

    Roskovensky, John K.; Nandy, Prabal; Post, Brian N

    2012-01-10

    A computer-automated method for detecting a vessel in water based on an image of a portion of Earth includes generating a thermal anomaly mask. The thermal anomaly mask flags each pixel of the image initially deemed to be a wake pixel based on a comparison of a thermal value of each pixel against other thermal values of other pixels localized about each pixel. Contiguous pixels flagged by the thermal anomaly mask are grouped into pixel clusters. A shape of each of the pixel clusters is analyzed to determine whether each of the pixel clusters represents a possible vessel detection event. The possible vessel detection events are represented visually within the image.

  1. Wake potentials of the ILC Interaction Region

    SciTech Connect (OSTI)

    Novokhatski, A.; /SLAC

    2011-08-16

    The vacuum chamber of the ILC Interaction Region (IR) is optimized for best detector performance. It has special shaping to minimize additional backgrounds due to the metal part of the chamber. Also, for the same reason this thin vacuum chamber does not have water cooling. Therefore, small amounts of power, which may be deposited in the chamber, can be enough to raise the chamber to a high temperature. One of the sources of 'heating' power is the electromagnetic field of the beam. This field diffracts by non-regularities of the beam pipe and excites free-propagating fields, which are then absorbed by the pipe wall. In addition we have a heating power of the image currents due to finite conductivity of the metallic wall. We will discuss these effects as updating the previous results. The conclusions of this report are: (1) The amount of the beam energy loss in IR is almost equal to the energy loss in one ILC (TESLA) accelerating cryo-module; (2) Addition energy spread at IR is very small; (3) Spectrum of the wake fields is limited 300 GHz; (4) Average power of the wake fields excited in IR is 30 W for nominal ILC parameters; and (5) Pulse power in this case is 6 kilowatts.

  2. Manufacturing's Wake-Up Call | Department of Energy

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

    Manufacturing's Wake-Up Call Manufacturing's Wake-Up Call booz_and_um_aug2011.pdf (609.61 KB) More Documents & Publications Visiting Speaker Program - January 12, 2009 CEMI Days Factsheet Report to the President on Capturing Domestic Competitive Advantage in Advanced Manufacturing

  3. Advancing Development and Greenhouse Gas Reductions in Vietnam's Wind Sector

    SciTech Connect (OSTI)

    Bilello, D.; Katz, J.; Esterly, S.; Ogonowski, M.

    2014-09-01

    Clean energy development is a key component of Vietnam's Green Growth Strategy, which establishes a target to reduce greenhouse gas (GHG) emissions from domestic energy activities by 20-30 percent by 2030 relative to a business-as-usual scenario. Vietnam has significant wind energy resources, which, if developed, could help the country reach this target while providing ancillary economic, social, and environmental benefits. Given Vietnam's ambitious clean energy goals and the relatively nascent state of wind energy development in the country, this paper seeks to fulfill two primary objectives: to distill timely and useful information to provincial-level planners, analysts, and project developers as they evaluate opportunities to develop local wind resources; and, to provide insights to policymakers on how coordinated efforts may help advance large-scale wind development, deliver near-term GHG emission reductions, and promote national objectives in the context of a low emission development framework.

  4. Wind Turbine Wake-Redirection Control at the Fishermen's Atlantic City Windfarm: Preprint

    SciTech Connect (OSTI)

    Churchfield, M.; Fleming, P.; Bulder, B.; White, S.

    2015-05-06

    In this paper, we will present our work towards designing a control strategy to mitigate wind turbine wake effects by redirecting the wakes, specifically applied to the Fishermen’s Atlantic City Windfarm (FACW), proposed for deployment off the shore of Atlantic City, New Jersey. As wind turbines extract energy from the air, they create low-speed wakes that extend behind them. Full wake recovery Full wake recovery to the undisturbed wind speed takes a significant distance. In a wind energy plant the wakes of upstream turbines may travel downstream to the next row of turbines, effectively subjecting them to lower wind speeds, meaning these waked turbines will produce less power.

  5. Wake Fields in the Super B Factory Interaction Region

    SciTech Connect (OSTI)

    Weathersby, Stephen; Novokhatski, Alexander; /SLAC

    2011-06-02

    The geometry of storage ring collider interaction regions present an impedance to beam fields resulting in the generation of additional electromagnetic fields (higher order modes or wake fields) which affect the beam energy and trajectory. These affects are computed for the Super B interaction region by evaluating longitudinal loss factors and averaged transverse kicks for short range wake fields. Results indicate at least a factor of 2 lower wake field power generation in comparison with the interaction region geometry of the PEP-II B-factory collider. Wake field reduction is a consderation in the Super B design. Transverse kicks are consistent with an attractive potential from the crotch nearest the beam trajectory. The longitudinal loss factor scales as the -2.5 power of the bunch length. A factor of 60 loss factor reduction is possible with crotch geometry based on an intersecting tubes model.

  6. Ionization-Induced Electron Trapping inUltrarelativistic Plasma Wakes

    SciTech Connect (OSTI)

    Oz, E.; Deng, S.; Katsouleas, T.; Muggli, P.; Barnes, C.D.; Blumenfeld, I.; Decker, F.J.; Emma, P.; Hogan, M.J.; Ischebeck, R.; Iverson, R.H.; Kirby, N.; Krejcik, P.; O'Connell, C.; Siemann, R.H.; Walz, D.; Auerbach, D.; Clayton, C.E.; Huang, C.; Johnson, D.K.; Joshi, C.; /UCLA

    2007-04-06

    The onset of trapping of electrons born inside a highly relativistic, 3D beam-driven plasma wake is investigated. Trapping occurs in the transition regions of a Li plasma confined by He gas. Li plasma electrons support the wake, and higher ionization potential He atoms are ionized as the beam is focused by Li ions and can be trapped. As the wake amplitude is increased, the onset of trapping is observed. Some electrons gain up to 7.6 GeV in a 30.5 cm plasma. The experimentally inferred trapping threshold is at a wake amplitude of 36 GV/m, in good agreement with an analytical model and PIC simulations.

  7. Sandia Energy - CFD-Populated Empirical Turbine Wake Model

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

    parameters that effect tidal turbine wakes, such as yaw angle to incident flow and vertical blockage ratio, may be incorporated as part of future revisions of the CFD populated...

  8. Sandia Energy - Wake-Imaging System Progresses to Outdoor Scaled...

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

    data collected will improve the physical understanding and modeling of wind-turbine wake impacts on the power production and loads of down-wind turbines in a wind plant. Schematic...

  9. Challenges to institutionalizing strategic environmental assessment: The case of Vietnam

    SciTech Connect (OSTI)

    Slunge, Daniel; Tran, Trang Thi Huyen

    2014-09-15

    Building on new institutional theory, this paper develops an analytical framework for analyzing constraints to the institutionalization of strategic environmental assessment (SEA) at four different institutional levels. The framework is tested in an empirical analysis of the environmental assessment system in Vietnam, which is a frontrunner among developing countries regarding the introduction and use of SEA. Building on interviews with Vietnamese and international experts, as well as an extensive literature review, we identify institutional constraints which challenge the effective use of SEA in Vietnam. We conclude that commonly identified constraints, such as inadequate training, technical guidelines, baseline data and financial resources, are strongly linked to constraints at higher institutional levels, such as incentives to not share information between ministries and severe restrictions on access to information and public participation. Without a thorough understanding of these institutional constraints, there is a risk that attempts to improve the use of SEA are misdirected. Thus, a careful institutional analysis should guide efforts to introduce and improve the use of SEA in Vietnam and other developing countries. The analytical framework for analyzing constraints to institutionalization of SEA presented in this paper represents a systematic effort in this direction. - Highlights: • A framework for analyzing constraints to institutionalizing SEA is developed • Empirical analysis of the strategic environmental assessment system in Vietnam • Constraints in the action arena linked to deeper institutional constraints • Institutional analysis needed prior to introducing SEA in developing countries.

  10. Plasma wake field XUV radiation source

    DOE Patents [OSTI]

    Prono, Daniel S.; Jones, Michael E.

    1997-01-01

    A XUV radiation source uses an interaction of electron beam pulses with a gas to create a plasma radiator. A flowing gas system (10) defines a circulation loop (12) with a device (14), such as a high pressure pump or the like, for circulating the gas. A nozzle or jet (16) produces a sonic atmospheric pressure flow and increases the density of the gas for interacting with an electron beam. An electron beam is formed by a conventional radio frequency (rf) accelerator (26) and electron pulses are conventionally formed by a beam buncher (28). The rf energy is thus converted to electron beam energy, the beam energy is used to create and then thermalize an atmospheric density flowing gas to a fully ionized plasma by interaction of beam pulses with the plasma wake field, and the energetic plasma then loses energy by line radiation at XUV wavelengths Collection and focusing optics (18) are used to collect XUV radiation emitted as line radiation when the high energy density plasma loses energy that was transferred from the electron beam pulses to the plasma.

  11. NNSA Continues to Assist Vietnam in Enhancing its Nuclear/Radiological...

    National Nuclear Security Administration (NNSA)

    NNSA Continues to Assist Vietnam in Enhancing its NuclearRadiological Emergency Program August 27, 2014 WASHINGTON, D.C. - The National Nuclear Security Administration (NNSA) is ...

  12. Vietnam-NIES Low-Carbon Society Scenarios 2050 | Open Energy...

    Open Energy Info (EERE)

    NIES Low-Carbon Society Scenarios 2050 Jump to: navigation, search Name Vietnam-NIES Low-Carbon Society Scenarios 2050 AgencyCompany Organization National Institute for...

  13. Hydrokinetic canal measurements: inflow velocity, wake flow velocity, and turbulence

    SciTech Connect (OSTI)

    Gunawan, Budi

    2014-06-11

    The dataset consist of acoustic Doppler current profiler (ADCP) velocity measurements in the wake of a 3-meter diameter vertical-axis hydrokinetic turbine deployed in Roza Canal, Yakima, WA, USA. A normalized hub-centerline wake velocity profile and two cross-section velocity contours, 10 meters and 20 meters downstream of the turbine, are presented. Mean velocities and turbulence data, measured using acoustic Doppler velocimeter (ADV) at 50 meters upstream of the turbine, are also presented. Canal dimensions and hydraulic properties, and turbine-related information are also included.

  14. Review of Wind Turbine Wake Models and Future Directions (Presentation)

    SciTech Connect (OSTI)

    Churchfield, M. J.

    2013-08-01

    This presentation gives a brief overview to wind turbine wake modeling, ranging from models used in the 1980s up to the present. The presentation shows the strengths and weaknesses of various models and discusses the needs of the wind energy industry and research sectors. Both power production and loads analysis are discussed.

  15. Attachment L-7b Vietnam Design Requirements Document is an Official

    National Nuclear Security Administration (NNSA)

    b Vietnam Design Requirements Document is an Official Use Only document please see Section NNS-L-2000 for instructions to Obtain. Section NNS-L-2000 (a) (8) Official Use Only (OUO) Document. The Government considers the Vietnam Design Requirements Document, Attachment L-7b an OUO Document and it cannot be made available to the public via any public webpages (e.g. FebBizOpps, FedConnect, DICCE2 acquisition webpage, Reading Room). The Vietnam Design Requirements Document (DRD) may assist Offerors

  16. Surface wake in the random-phase approximation

    SciTech Connect (OSTI)

    Garcia de Abajo, F.J. ); Echenique, P.M. )

    1993-11-01

    The scalar-electric-potential distribution set up by an ion traveling in the vicinity of a plane solid-vacuum interface, that is, the surface-wake potential, is investigated with the specular-reflection model to describe the response of the surface and with the random-phase approximation for the dielectric function of the bulk material. This permits us to address the study of the low-velocity surface wake: the static potential is found to have a dip at the position of the ion; that dip is shifted towards the direction opposite to the velocity vector for velocities smaller than the threshold of creation of plasmons ([approx]1.3[ital v][sub [ital F

  17. Semiclassical eigenenergies in the wake of fast ions in solids

    SciTech Connect (OSTI)

    Mueller, J.; Burgdoerfer, J.; Noid, D.W. (Tennessee Univ., Knoxville, TN (USA). Dept. of Physics Oak Ridge National Lab., TN (USA))

    1990-01-01

    We compare the semiclassical and quantum mechanical eigenenergies of an electron in the wake of a fast, highly charged ion traversing a solid. The classical dynamics of this system shows a transition from regular to chaotic motion as a function of the binding energy. The transition can also be seen in the quantal spectra. We find evidence for a connection between bifurcation of tori and disorder in the energy level sequences. 21 refs., 4 figs.

  18. Windmill wake turbulence decay: a preliminary theoretical model

    SciTech Connect (OSTI)

    Bossanyi, E.A.

    1983-02-01

    The results are given of initial theoretical attempts to predict dynamic wake characteristics, particularly turbulence decay, downstream of wind turbine generators in order to assess the potential for acoustic noise generation in clusters or arrays of turbines. These results must be considered preliminary, because the model described is at least partially based on the assumption of isotropy in the turbine wakes; however, anisotrpic conditions may actually exist, particularly in the near-wake regions. The results indicate that some excess spectral energy may still exist. The turbine-generated turbulence from one machine can reach the next machine in the cluster and, depending on the turbulent wavelengths critical for acoustic noise production and perhaps structural excitation, this may be a cause for concern. Such a situation is most likely to occur in the evening or morining, during the transition from the daytime to the nocturnal boundary layer and vice-versa, particularly at more elevated sites where the winds tend to increase after dark.

  19. Overview of cleaner production as a result of clean technology research in Vietnam

    SciTech Connect (OSTI)

    Sam, D.V.; Nhan, T.V.; Lan, N.N.

    1996-12-31

    Vietnam is beginning its industrialization process, and it currently lacks the capital necessary for expensive pollution control and treatment systems. Pollution strategies are critical for the country. This study evaluates the present status of industry and the pollution problems associated with industrial development in Vietnam. The purpose of the study is to identify sectors that may have potential for promoting cleaner production practices. 4 refs.

  20. Multidisciplinary Research on Wake Control in Wind Power Plants at NREL

    SciTech Connect (OSTI)

    Gebraad, Pieter; Fleming, Paul; Wright, Alan; Dykes, Katherine; van Wingerden, Jan-Willem

    2015-07-08

    Presentation slides given at WINDFARMS 2015. The presentation gives an overview of National Renewable Energy Laboratory's work on wake control in wind power plants.

  1. High-Efficiency Absorber for Damping the Transverse Wake Fields

    SciTech Connect (OSTI)

    Novokhatski, A.; Seeman, J.; Weathersby, S.; /SLAC

    2007-02-28

    Transverse wake fields generated by intense beams may propagate long distances in the vacuum chamber and dissipate power in different shielded elements such as bellows, vacuum valves or vacuum pumps. Induced heating in these elements may be high enough to deteriorate vacuum conditions. We have developed a broadband water-cooled bellows-absorber to capture and damp these harmful transverse fields without impacting the longitudinal beam impedance. Experimental results at the PEP-II SLAC B-factory demonstrate high efficiency of this device. This absorber may be useful in other machines like synchrotron light sources or International Linear Collider.

  2. Imaging doppler lidar for wind turbine wake profiling

    SciTech Connect (OSTI)

    Bossert, David J.

    2015-11-19

    An imaging Doppler lidar (IDL) enables the measurement of the velocity distribution of a large volume, in parallel, and at high spatial resolution in the wake of a wind turbine. Because the IDL is non-scanning, it can be orders of magnitude faster than conventional coherent lidar approaches. Scattering can be obtained from naturally occurring aerosol particles. Furthermore, the wind velocity can be measured directly from Doppler shifts of the laser light, so the measurement can be accomplished at large standoff and at wide fields-of-view.

  3. Building on and spinning off: Sandia National Labs` creation of sensors for Vietnam

    SciTech Connect (OSTI)

    Ullrich, R.

    1996-12-31

    This paper discusses Sandia National Laboratories` development of new technologies for use in the Vietnam War - specifically the seismic sensors deployed to detect troop and vehicle movement - first along the Ho Chi Minh Trail and later in perimeter defense for American military encampments in South Vietnam. Although the sensor story is a small one, it is interesting because it dovetails nicely with our understanding of the war in Vietnam and its frustrations; of the creation of new technologies for war and American enthusiasm for that technology; and of a technological military and the organizational research and a m am development structure created to support it. Within the defense establishment, the sensors were proposed within the context of a larger concept - that of a barrier to prevent the infiltration of troops and supplies from North Vietnam to the South. All of the discussion of the best way to fight in Vietnam is couched in the perception that this was a different kind of war than America was used to fighting. The emphasis was on countering the problems posed by guerrilla/revolutionary warfare and eventually by the apparent constraints of being involved in a military action, not an outright war. The American response was to find the right technology to do the job - to control the war by applying a technological tincture to its wounds and to make the war familiar and fightable on American terms. And, when doubts were raised about the effectiveness of applying existing technologies (namely, the bombing of North Vietnam and Laos), the doubters turned to new technologies. The sensors that were developed for use in Vietnam were a direct product of this sort of thinking - on the part of the engineers at Sandia who created the sensors, the civilian scientific advisors who recommended them, and, ultimately, the soldiers in the field who had to use them.

  4. Simulation Comparison of Wake Mitigation Control Strategies for a Two-Turbine Case

    SciTech Connect (OSTI)

    Fleming, Paul; Gebraad, Pieter M. O.; Lee, Sang; van Wingerden, Jan-Willem; Johnson, Kathryn; Churchfield, Matt; Michalakes, John; Spalart, Philippe; Moriarty, Patrick

    2015-12-01

    Wind turbines arranged in a wind plant impact each other through their wakes. Wind plant control is an active research field that attempts to improve wind plant performance by coordinating control of individual turbines to take into account these turbine–wake interactions. High-fidelity simulations of a two-turbine fully waked scenario are used to investigate several wake mitigation strategies, in this paper, including modification of yaw and tilt angles of an upstream turbine to induce wake skew, as well as repositioning of the downstream turbine. The simulation results are compared through change relative to a baseline operation in terms of overall power capture and loading on the upstream and downstream turbine. Results demonstrated improved power production for all methods. Moreover, analysis of control options, including individual pitch control, shows potential to minimize the increase of, or even reduce, turbine loads.

  5. An evaluation of the environmental impact assessment system in Vietnam: The gap between theory and practice

    SciTech Connect (OSTI)

    Clausen, Alison; Vu, Hoang Hoa; Pedrono, Miguel

    2011-03-15

    Vietnam has one of the fastest growing economies in the world and has achieved significant socio-economic development in recent years. However this growth is placing increased pressure on an already depleted natural environment. Environmental impact assessment (EIA) is recognised by the Government and international organizations as an important tool in the management of the impacts of future development on the country's natural resource base. The Government's commitment to EIA has been demonstrated through the development and adoption of the Law on Environment Protection (Revised) in 2005 which sets out the requirements for EIA and which represents a major step in the development of a robust legislative framework for EIA in Vietnam. The Law on Environment Protection (Revised) 2005 has now been operational for several years and we have undertaken an evaluation of the resulting EIA system in Vietnam. We argue that while significant improvements have been achieved in the EIA policy framework, an important gap remains between EIA theory and practice. We contend that the basis of the current EIA legislation is strong and that future developments of the EIA system in Vietnam should focus on improving capacity of EIA practitioners rather than further substantial legislative change. Such improvements would allow the Vietnamese EIA system to emerge as an effective and efficient tool for environmental management in Vietnam and as a model EIA framework for other developing countries.

  6. Energy Spread Reduction of Electron Beams Produced via Laser Wake

    SciTech Connect (OSTI)

    Pollock, Bradley Bolt

    2012-01-01

    Laser wakefield acceleration of electrons holds great promise for producing ultra-compact stages of GeV scale, high quality electron beams for applications such as x-ray free electron lasers and high energy colliders. Ultra-high intensity laser pulses can be self-guided by relativistic plasma waves over tens of vacuum diffraction lengths, to give >1 GeV energy in cm-scale low density plasma using ionization-induced injection to inject charge into the wake at low densities. This thesis describes a series of experiments which investigates the physics of LWFA in the self-guided blowout regime. Beginning with high density gas jet experiments the scaling of the LWFA-produced electron beam energy with plasma electron density is found to be in excellent agreement with both phenomenological theory and with 3-D PIC simulations. It is also determined that self-trapping of background electrons into the wake exhibits a threshold as a function of the electron density, and at the densities required to produce electron beams with energies exceeding 1 GeV a different mechanism is required to trap charge into low density wakes. By introducing small concentrations of high-Z gas to the nominal He background the ionization-induced injection mechanism is enabled. Electron trapping is observed at densities as low as 1.3 x 1018 cm-3 in a gas cell target, and 1.45 GeV electrons are demonstrated for the first time from LWFA. This is currently the highest electron energy ever produced from LWFA. The ionization-induced trapping mechanism is also shown to generate quasi-continuous electron beam energies, which is undesirable for accelerator applications. By limiting the region over which ionization-induced trapping occurs, the energy spread of the electron beams can be controlled. The development of a novel two-stage gas cell target provides the capability to tailor the gas composition in the longitudinal direction, and confine the trapping process to occur only in a

  7. COAXIAL TWO-CHANNEL DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Hirshfield, Jay L.

    2013-04-30

    Theory, computations, and experimental apparatus are presented that describe and are intended to confirm novel properties of a coaxial two-channel dielectric wake field accelerator. In this configuration, an annular drive beam in the outer coaxial channel excites multimode wakefields which, in the inner channel, can accelerate a test beam to an energy much higher than the energy of the drive beam. This high transformer ratio is the result of judicious choice of the dielectric structure parameters, and of the phase separation between drive bunches and test bunches. A structure with cm-scale wakefields has been build for tests at the Argonne Wakefield Accelerator Laboratory, and a structure with mm-scale wakefields has been built for tests at the SLAC FACET facility. Both tests await scheduling by the respective facilities.

  8. Kinetic electron and ion instability of the lunar wake simulated at physical mass ratio

    SciTech Connect (OSTI)

    Haakonsen, Christian Bernt Hutchinson, Ian H. Zhou, Chuteng

    2015-03-15

    The solar wind wake behind the moon is studied with 1D electrostatic particle-in-cell (PIC) simulations using a physical ion to electron mass ratio (unlike prior investigations); the simulations also apply more generally to supersonic flow of dense magnetized plasma past non-magnetic objects. A hybrid electrostatic Boltzmann electron treatment is first used to investigate the ion stability in the absence of kinetic electron effects, showing that the ions are two-stream unstable for downstream wake distances (in lunar radii) greater than about three times the solar wind Mach number. Simulations with PIC electrons are then used to show that kinetic electron effects can lead to disruption of the ion beams at least three times closer to the moon than in the hybrid simulations. This disruption occurs as the result of a novel wake phenomenon: the non-linear growth of electron holes spawned from a narrow dimple in the electron velocity distribution. Most of the holes arising from the dimple are small and quickly leave the wake, approximately following the unperturbed electron phase-space trajectories, but some holes originating near the center of the wake remain and grow large enough to trigger disruption of the ion beams. Non-linear kinetic-electron effects are therefore essential to a comprehensive understanding of the 1D electrostatic stability of such wakes, and possible observational signatures in ARTEMIS data from the lunar wake are discussed.

  9. Effect of nonlinear chirped Gaussian laser pulse on plasma wake field generation

    SciTech Connect (OSTI)

    Afhami, Saeedeh; Eslami, Esmaeil

    2014-08-15

    An ultrashort laser pulse propagating in plasma can excite a nonlinear plasma wake field which can accelerate charged particles up to GeV energies within a compact space compared to the conventional accelerator devices. In this paper, the effect of different kinds of nonlinear chirped Gaussian laser pulse on wake field generation is investigated. The numerical analysis of our results depicts that the excitation of plasma wave with large and highly amplitude can be accomplished by nonlinear chirped pulses. The maximum amplitude of excited wake in nonlinear chirped pulse is approximately three times more than that of linear chirped pulse. In order to achieve high wake field generation, chirp parameters and functions should be set to optimal values.

  10. The 21 cm signature of shock heated and diffuse cosmic string wakes

    SciTech Connect (OSTI)

    Hernndez, Oscar F.; Brandenberger, Robert H. E-mail: rhb@physics.mcgill.ca

    2012-07-01

    The analysis of the 21 cm signature of cosmic string wakes is extended in several ways. First we consider the constraints on G? from the absorption signal of shock heated wakes laid down much later than matter radiation equality. Secondly we analyze the signal of diffuse wake, that is those wakes in which there is a baryon overdensity but which have not shock heated. Finally we compare the size of these signals to the expected thermal noise per pixel which dominates over the background cosmic gas brightness temperature and find that the cosmic string signal will exceed the thermal noise of an individual pixel in the Square Kilometre Array for string tensions G? > 2.5 10{sup ?8}.

  11. Methods for estimating wake flow and effluent dispersion near simple block-like buildings

    SciTech Connect (OSTI)

    Hosker, R.P. Jr.

    1981-05-01

    This report is intended as an interim guide for those who routinely face air quality problems associated with near-building exhaust stack placement and height, and the resulting concentration patterns. Available data and methods for estimating wake flow and effluent dispersion near isolated block-like structures are consolidated. The near-building and wake flows are described, and quantitative estimates for frontal eddy size, height and extent of roof and wake cavities, and far wake behavior are provided. Concentration calculation methods for upwind, near-building, and downwind pollutant sources are given. For an upwind source, it is possible to estimate the required stack height, and to place upper limits on the likely near-building concentration. The influences of near-building source location and characteristics relative to the building geometry and orientation are considered. Methods to estimate effective stack height, upper limits for concentration due to flush roof vents, and the effect of changes in rooftop stack height are summarized. Current wake and wake cavity models are presented. Numerous graphs of important expressions have been prepared to facilitate computations and quick estimates of flow patterns and concentration levels for specific simple buildings. Detailed recommendations for additional work are given.

  12. Synergistic Effects of Turbine Wakes and Atmospheric Stability on Power Production at an Onshore Wind Farm

    SciTech Connect (OSTI)

    Wharton, S; Lundquist, J K; Marjanovic, N

    2012-01-25

    This report examines the complex interactions between atmospheric stability and turbine-induced wakes on downwind turbine wind speed and power production at a West Coast North American multi-MW wind farm. Wakes are generated when the upwind flow field is distorted by the mechanical movement of the wind turbine blades. This has two consequences for downwind turbines: (1) the downwind turbine encounters wind flows with reduced velocity and (2) the downwind turbine encounters increased turbulence across multiple length scales via mechanical turbulence production by the upwind turbine. This increase in turbulence on top of ambient levels may increase aerodynamic fatigue loads on the blades and reduce the lifetime of turbine component parts. Furthermore, ambient atmospheric conditions, including atmospheric stability, i.e., thermal stratification in the lower boundary layer, play an important role in wake dissipation. Higher levels of ambient turbulence (i.e., a convective or unstable boundary layer) lead to higher turbulent mixing in the wake and a faster recovery in the velocity flow field downwind of a turbine. Lower levels of ambient turbulence, as in a stable boundary layer, will lead to more persistent wakes. The wake of a wind turbine can be divided into two regions: the near wake and far wake, as illustrated in Figure 1. The near wake is formed when the turbine structure alters the shape of the flow field and usually persists one rotor diameter (D) downstream. The difference between the air inside and outside of the near wake results in a shear layer. This shear layer thickens as it moves downstream and forms turbulent eddies of multiple length scales. As the wake travels downstream, it expands depending on the level of ambient turbulence and meanders (i.e., travels in non-uniform path). Schepers estimates that the wake is fully expanded at a distance of 2.25 D and the far wake region begins at 2-5 D downstream. The actual distance traveled before the wake

  13. Wake of the MOD-0A1 wind turbine at two rotor diameters downwind on December 3, 1981

    SciTech Connect (OSTI)

    Connell, J.R.; George, R.L.

    1982-11-01

    The wake of the MOD-0A1 wind turbine at Clayton, New Mexico has been measured using a vertical plane array of anemometers in a crosswind plane at a distance of two rotor diameters directly downwind of the turbine. Rotor blade vortices were well mixed into the wake turbulence and were not separately detectable. Wake swirl about the along-wind axis had a value not greater than 0.025 rad/s. Extra turbulence energy existed in the edge of the wake at a frequency of about n=0.025 Hz. The cross-wake plane analyses of wind speeds revealed a nearly circular inner portion and a strongly elliptical portion. The elliptical portion major axis was horizontal. An estimate of the average rate of reenergizing of the wake, using measurements of mean wind energy flow and turbine power, suggests that entrainment with ambient air may have been rapid. Some wake characteristics were compared with the corresponding ones for several simple wake models based upon concepts of mixing of ambient air into a wake or an equivalent coaxial jet. (LEW)

  14. Wake-up effects in Si-doped hafnium oxide ferroelectric thin films

    SciTech Connect (OSTI)

    Zhou, Dayu, E-mail: zhoudayu@dlut.edu.cn [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China) [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Key Laboratory for Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024 (China); State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China); Xu, Jin [Department of Electronic Engineering, Dalian Neusoft University of Information, Dalian 116023 (China)] [Department of Electronic Engineering, Dalian Neusoft University of Information, Dalian 116023 (China); Li, Qing; Guan, Yan [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China)] [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Cao, Fei; Dong, Xianlin [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China)] [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Mller, Johannes [Fraunhofer IPMS-CNT, Koengisbruecker Strasse 180, 01109 Dresden (Germany)] [Fraunhofer IPMS-CNT, Koengisbruecker Strasse 180, 01109 Dresden (Germany); Schenk, Tony; Schrder, Uwe [Namlab gGmbH/TU Dresden, Noethnitzer Strasse 64, 01187 Dresden (Germany)] [Namlab gGmbH/TU Dresden, Noethnitzer Strasse 64, 01187 Dresden (Germany)

    2013-11-04

    Hafnium oxide based ferroelectric thin films have shown potential as a promising alternative material for non-volatile memory applications. This work reports the switching stability of a Si-doped HfO{sub 2} film under bipolar pulsed-field operation. High field cycling causes a wake-up in virgin pinched polarization hysteresis loops, demonstrated by an enhancement in remanent polarization and a shift of negative coercive voltage. The rate of wake-up is accelerated by either reducing the frequency or increasing the amplitude of the cycling field. We suggest de-pinning of domains due to reduction of the defect concentration at bottom electrode interface as origin of the wake-up.

  15. Wake deficit measurements on the Jess and Souza Ranches, Altamont Pass

    SciTech Connect (OSTI)

    Nierenburg, R. (Altamont Energy Corp., San Rafael, CA (USA))

    1990-04-01

    This report is ninth in a series of documents presenting the findings of field test under DOE's Cooperative Field Test Program (CFTP) with the wind industry. This report provides results of a project conducted by Altamont Energy Corp. (AEC) to measure wake deficits on the Jess and Sousa Ranches in Altamont Pass, CA. This research enhances and complements other DOE-funded projects to refine estimates of wind turbine array effects. This project will help explain turbine performance variability caused by wake effects. 4 refs., 28 figs., 106 tabs.

  16. Wake Flow Simulations for a Mid-Sized Rim Driven Wind Turbine

    SciTech Connect (OSTI)

    Rob O. Hovsapian; Various

    2014-06-01

    The onshore land where wind farms with conventional wind turbines can be places is limited by various factors including a requirement for relatively high wind speed for turbines' efficient operations. Where such a requirement cannot be met, mid-and small-sized turbines can be a solution. In the current paper simulations for near and for wakes behind a mid-sized Rim Driven Wind Turbine developed by Keuka Energy LLC is analyzed. The purposes of this study is to better understand the wake structure for more efficient wind farm planning. Simulations are conducted with the commercial CFD software STARCCM+

  17. Wind Turbine Wake Measurements in the Operating Region of a Tail Vain

    SciTech Connect (OSTI)

    Larwood, S.

    2001-01-22

    In conjunction with the National Renewable Energy Laboratory's (NREL's) Unsteady Aerodynamics Experiment (UAE) at NASA Ames, we measured the wake of an upwind 10-meter (m) diameter wind turbine in the typical region of a tail vane. The experiment was performed in a 24.4-by-36.6-m wind tunnel. We placed two sonic anemometers 0.58 rotor diameters downwind of the rotor at hub height. One was positioned nominally behind the nacelle at 9% radius and the second was placed 2-m outboard at 49% radius. The tunnel wind speed was varied from 5 to 25 meters per second (m/s) and the turbine rotor speed was held at 72 revolutions per minute (rpm). We varied yaw from 0{degree} to 60{degree}. The data showed unsteadiness in the wake due to the nacelle wake. Also, the unsteadiness increased with the onset of blade stall. The axial induction factor in the wake showed that the turbine was operating within the windmill brake state of actuator disk momentum theory. Little variation in unsteadiness was shown under yawed conditions. We also discovered that lateral velocity behind the nacelle was negative and would result in an unfurling normal force on a tail vane. The vertical velocity was shown to change sign under yawed conditions, conceivably as a result of the opposing blade root vortex.

  18. Observations of wake characteristics at the Goodnoe Hills MOD-2 array

    SciTech Connect (OSTI)

    Buck, J.W.; Renne, D.S.

    1985-08-01

    The array of three MOD-2 wind turbines and two meteorological towers at Goodnoe Hills, Washington, provides an opportunity to evaluate turbine and wake interactions in a real environment. The triangular arrangement of the three turbines provides opportunities to study the effect of wakes on the performance of a downwind turbine at three different distances: 5, 7, and 10 rotor diameters (D), where 1 D is 300 ft. The information obtained from this test configuration is critical to future wind farm activities and is a key objective of the MOD-2 test program. This report describes the analysis of data measured at the turbines and towers from August 29 to November 12, 1982. The data are 2-min averages of 1-s values. Background flow characteristics were also examined to determine if flow variations across the site could mask wake measurements. For this analysis, one year's data gathered at the meteorological towers were analyzed. The results show some differences between characteristics measured at the towers, but these differences were not great enough to consider in evaluating wakes at the towers.

  19. Sandia Wake-Imaging System Successfully Deployed at Scaled Wind Farm

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

    Technology Facility Wake-Imaging System Successfully Deployed at Scaled Wind Farm Technology Facility - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid

  20. Virtual LIDAR Model Helps Researchers Plan for Wake Steering Experiment at

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

    SWiFT Model Helps Researchers Plan for Wake Steering Experiment at SWiFT - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear

  1. Virtual LIDAR model helps researchers plan for the Wake Steering Experiment

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

    at SWiFT model helps researchers plan for the Wake Steering Experiment at SWiFT - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing

  2. Multiple self-injection in the acceleration of monoenergetic electrons by a laser wake field

    SciTech Connect (OSTI)

    Oguchi, A.; Takano, K.; Hotta, E.; Zhidkov, A.; Nemoto, K.; Nakajima, K.

    2008-04-15

    Multiple electron self-injection in laser wake-field acceleration is studied via fully relativistic two- and three-dimensional particle-in-cell simulation. The electron density modulation in the laser wake originating from oscillations of the laser pulse waist and relativistic effects can provoke the parametric resonance in the electron fluid momentum. This may result in repetitive trapping of plasma electrons in the acceleration phase of the laser wake: multiple electron self-injection. The maximal energy of the accelerated electrons depends strongly on the total charge of the injected electrons. A low energy spread, less than 1%, for an almost 1 GeV energy electron beam with charge about 10 pC is found numerically in the plasma channel irradiated by a 25 TW laser pulse, while a 200 TW laser pulse produces a few nC beam with only 150 MeV energy. Essentially thermalization of accelerated electrons is also a result of charge loading.

  3. Comparison of the Dynamic Wake Meandering Model, Large-Eddy Simulation, and Field Data at the Egmond aan Zee Offshore Wind Plant: Preprint

    SciTech Connect (OSTI)

    Churchfield, M. J.; Moriarty, P. J.; Hao, Y.; Lackner, M. A.; Barthelmie, R.; Lundquist, J.; Oxley, G. S.

    2014-12-01

    The focus of this work is the comparison of the dynamic wake meandering model and large-eddy simulation with field data from the Egmond aan Zee offshore wind plant composed of 36 3-MW turbines. The field data includes meteorological mast measurements, SCADA information from all turbines, and strain-gauge data from two turbines. The dynamic wake meandering model and large-eddy simulation are means of computing unsteady wind plant aerodynamics, including the important unsteady meandering of wakes as they convect downstream and interact with other turbines and wakes. Both of these models are coupled to a turbine model such that power and mechanical loads of each turbine in the wind plant are computed. We are interested in how accurately different types of waking (e.g., direct versus partial waking), can be modeled, and how background turbulence level affects these loads. We show that both the dynamic wake meandering model and large-eddy simulation appear to underpredict power and overpredict fatigue loads because of wake effects, but it is unclear that they are really in error. This discrepancy may be caused by wind-direction uncertainty in the field data, which tends to make wake effects appear less pronounced.

  4. In the wake of high-profile battery fires, a safer approach emerges >

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

    Archived News Stories > The Energy Materials Center at Cornell Archived News Stories Latest News The perfect atom sandwich requires an extra layer › Cornell boasts 22 'highly cited' researchers › Postdoc brings open access issue to the table › In This Section EMC2 News Archived News Stories In the wake of high-profile battery fires, a safer approach emerges May 14th, 2014 › ACS News Service Weekly PressPac "Suppression of Lithium Dendrite Growth Using Cross-Linked

  5. Wind Plant Power Optimization through Yaw Control using a Parametric Model for Wake Effects -- A CFD Simulation Study

    SciTech Connect (OSTI)

    Gebraad, P. M. O.; Teeuwisse, F. W.; van Wingerden, J. W.; Fleming, Paul A.; Ruben, S. D.; Marden, J. R.; Pao, L. Y.

    2016-01-01

    This article presents a wind plant control strategy that optimizes the yaw settings of wind turbines for improved energy production of the whole wind plant by taking into account wake effects. The optimization controller is based on a novel internal parametric model for wake effects, called the FLOw Redirection and Induction in Steady-state (FLORIS) model. The FLORIS model predicts the steady-state wake locations and the effective flow velocities at each turbine, and the resulting turbine electrical energy production levels, as a function of the axial induction and the yaw angle of the different rotors. The FLORIS model has a limited number of parameters that are estimated based on turbine electrical power production data. In high-fidelity computational fluid dynamics simulations of a small wind plant, we demonstrate that the optimization control based on the FLORIS model increases the energy production of the wind plant, with a reduction of loads on the turbines as an additional effect.

  6. The influence of magnetic fields on the wake field and stopping power of an ion-beam pulse in plasmas

    SciTech Connect (OSTI)

    Zhao, Xiao-ying; Zhang, Ya-ling; Duan, Wen-shan; Qi, Xin E-mail: lyang@impcas.ac.cn; Shi, Jian; Zhang, Ling-yu; Yang, Lei E-mail: lyang@impcas.ac.cn

    2015-09-15

    We performed two-dimensional particle-in-cell simulations to investigate how a magnetic field affects the wake field and stopping power of an ion-beam pulse moving in plasmas. The corresponding density of plasma electrons is investigated. At a weak magnetic field, the wakes exhibit typical V-shaped cone structures. As the magnetic field strengthens, the wakes spread and lose their typical V-shaped structures. At a sufficiently strong magnetic field, the wakes exhibit conversed V-shaped structures. Additionally, strengthening the magnetic field reduces the stopping power in regions of low and high beam density. However, the influence of the magnetic field becomes complicated in regions of moderate beam density. The stopping power increases in a weak magnetic field, but it decreases in a strong magnetic field. At high beam density and moderate magnetic field, two low-density channels of plasma electrons appear on both sides of the incident beam pulse trajectory. This is because electrons near the beam pulses will be attracted and move along with the beam pulses, while other electrons nearby are restricted by the magnetic field and cannot fill the gap.

  7. Sandia Wake Imaging System Field Test Report: 2015 Deployment at the Scaled Wind Farm Technology (SWiFT) Facility.

    SciTech Connect (OSTI)

    Naughton, Brian Thomas; Herges, Thomas

    2015-10-01

    This report presents the objectives, configuration, procedures, reporting , roles , and responsibilities and subsequent results for the field demonstration of the Sandia Wake Imaging System (SWIS) at the Sandia Scaled Wind Farm Technology (SWiFT) facility near Lubbock, Texas in June and July 2015.

  8. High redshift signatures in the 21 cm forest due to cosmic string wakes

    SciTech Connect (OSTI)

    Tashiro, Hiroyuki; Sekiguchi, Toyokazu; Silk, Joseph E-mail: toyokazu.sekiguchi@nagoya-u.jp

    2014-01-01

    Cosmic strings induce minihalo formation in the early universe. The resultant minihalos cluster in string wakes and create a ''21 cm forest'' against the cosmic microwave background (CMB) spectrum. Such a 21 cm forest can contribute to angular fluctuations of redshifted 21 cm signals integrated along the line of sight. We calculate the root-mean-square amplitude of the 21 cm fluctuations due to strings and show that these fluctuations can dominate signals from minihalos due to primordial density fluctuations at high redshift (z?>10), even if the string tension is below the current upper bound, G? < 1.5 10{sup ?7}. Our results also predict that the Square Kilometre Array (SKA) can potentially detect the 21 cm fluctuations due to strings with G? ? 7.5 10{sup ?8} for the single frequency band case and 4.0 10{sup ?8} for the multi-frequency band case.

  9. Large Eddy Simulation of Wind Turbine Wakes. Detailed Comparisons of Two Codes Focusing on Effects of Numerics and Subgrid Modeling

    SciTech Connect (OSTI)

    Martinez-Tossas, Luis A.; Churchfield, Matthew J.; Meneveau, Charles

    2015-06-18

    In this work we report on results from a detailed comparative numerical study from two Large Eddy Simulation (LES) codes using the Actuator Line Model (ALM). The study focuses on prediction of wind turbine wakes and their breakdown when subject to uniform inflow. Previous studies have shown relative insensitivity to subgrid modeling in the context of a finite-volume code. The present study uses the low dissipation pseudo-spectral LES code from Johns Hopkins University (LESGO) and the second-order, finite-volume OpenFOAMcode (SOWFA) from the National Renewable Energy Laboratory. When subject to uniform inflow, the loads on the blades are found to be unaffected by subgrid models or numerics, as expected. The turbulence in the wake and the location of transition to a turbulent state are affected by the subgrid-scale model and the numerics.

  10. Large Eddy Simulation of Wind Turbine Wakes. Detailed Comparisons of Two Codes Focusing on Effects of Numerics and Subgrid Modeling

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

    Martinez-Tossas, Luis A.; Churchfield, Matthew J.; Meneveau, Charles

    2015-06-18

    In this work we report on results from a detailed comparative numerical study from two Large Eddy Simulation (LES) codes using the Actuator Line Model (ALM). The study focuses on prediction of wind turbine wakes and their breakdown when subject to uniform inflow. Previous studies have shown relative insensitivity to subgrid modeling in the context of a finite-volume code. The present study uses the low dissipation pseudo-spectral LES code from Johns Hopkins University (LESGO) and the second-order, finite-volume OpenFOAMcode (SOWFA) from the National Renewable Energy Laboratory. When subject to uniform inflow, the loads on the blades are found to bemore » unaffected by subgrid models or numerics, as expected. The turbulence in the wake and the location of transition to a turbulent state are affected by the subgrid-scale model and the numerics.« less

  11. Preliminary Analysis on Linac Oscillation Data LI05-19 and Wake Field Energy Loss in FACET Commissioning 2012

    SciTech Connect (OSTI)

    Sun, Yipeng; /SLAC

    2012-07-23

    In this note, preliminary analysis on linac ocsillation data in FACET linac LI05-09 plus LI11-19 is presented. Several quadrupoles are identified to possibly have different strength, compared with their designed strength in the MAD optics model. The beam energy loss due to longitudinal wake fields in the S-band linac is also analytically calculated, also by LITRACK numerical simulations.

  12. Wind Plant Power Optimization through Yaw Control using a Parametric Model for Wake Effects -- A CFD Simulation Study

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

    Gebraad, P. M. O.; Teeuwisse, F. W.; van Wingerden, J. W.; Fleming, Paul A.; Ruben, S. D.; Marden, J. R.; Pao, L. Y.

    2016-01-01

    This article presents a wind plant control strategy that optimizes the yaw settings of wind turbines for improved energy production of the whole wind plant by taking into account wake effects. The optimization controller is based on a novel internal parametric model for wake effects, called the FLOw Redirection and Induction in Steady-state (FLORIS) model. The FLORIS model predicts the steady-state wake locations and the effective flow velocities at each turbine, and the resulting turbine electrical energy production levels, as a function of the axial induction and the yaw angle of the different rotors. The FLORIS model has a limitedmore » number of parameters that are estimated based on turbine electrical power production data. In high-fidelity computational fluid dynamics simulations of a small wind plant, we demonstrate that the optimization control based on the FLORIS model increases the energy production of the wind plant, with a reduction of loads on the turbines as an additional effect.« less

  13. Large-Eddy Simulation Study of Wake Propagation and Power Production in an Array of Tidal-Current Turbines: Preprint

    SciTech Connect (OSTI)

    Churchfield, M. J.; Li, Y.; Moriarty, P. J.

    2012-07-01

    This paper presents our initial work in performing large-eddy simulations of tidal turbine array flows. First, a horizontally-periodic precursor simulation is performed to create turbulent flow data. Then that data is used as inflow into a tidal turbine array two rows deep and infinitely wide. The turbines are modeled using rotating actuator lines, and the finite-volume method is used to solve the governing equations. In studying the wakes created by the turbines, we observed that the vertical shear of the inflow combined with wake rotation causes lateral wake asymmetry. Also, various turbine configurations are simulated, and the total power production relative to isolated turbines is examined. Staggering consecutive rows of turbines in the simulated configurations allows the greatest efficiency using the least downstream row spacing. Counter-rotating consecutive downstream turbines in a non-staggered array shows a small benefit. This work has identified areas for improvement, such as the use of a larger precursor domain to better capture elongated turbulent structures, the inclusion of salinity and temperature equations to account for density stratification and its effect on turbulence, improved wall shear stress modelling, and the examination of more array configurations.

  14. A summary of recent refinements to the WAKE dispersion model, a component of the HGSYSTEM/UF{sub 6} model suite

    SciTech Connect (OSTI)

    Yambert, M.W.; Lombardi, D.A.; Goode, W.D. Jr.; Bloom, S.G.

    1998-08-01

    The original WAKE dispersion model a component of the HGSYSTEM/UF{sub 6} model suite, is based on Shell Research Ltd.`s HGSYSTEM Version 3.0 and was developed by the US Department of Energy for use in estimating downwind dispersion of materials due to accidental releases from gaseous diffusion plant (GDP) process buildings. The model is applicable to scenarios involving both ground-level and elevated releases into building wake cavities of non-reactive plumes that are either neutrally or positively buoyant. Over the 2-year period since its creation, the WAKE model has been used to perform consequence analyses for Safety Analysis Reports (SARs) associated with gaseous diffusion plants in Portsmouth (PORTS), Paducah (PGDP), and Oak Ridge. These applications have identified the need for additional model capabilities (such as the treatment of complex terrain and time-variant releases) not present in the original utilities which, in turn, has resulted in numerous modifications to these codes as well as the development of additional, stand-alone postprocessing utilities. Consequently, application of the model has become increasingly complex as the number of executable, input, and output files associated with a single model run has steadily grown. In response to these problems, a streamlined version of the WAKE model has been developed which integrates all calculations that are currently performed by the existing WAKE, and the various post-processing utilities. This report summarizes the efforts involved in developing this revised version of the WAKE model.

  15. Quantifying error of lidar and sodar Doppler beam swinging measurements of wind turbine wakes using computational fluid dynamics

    SciTech Connect (OSTI)

    Lundquist, J. K.; Churchfield, M. J.; Lee, S.; Clifton, A.

    2015-02-23

    Wind-profiling lidars are now regularly used in boundary-layer meteorology and in applications such as wind energy and air quality. Lidar wind profilers exploit the Doppler shift of laser light backscattered from particulates carried by the wind to measure a line-of-sight (LOS) velocity. The Doppler beam swinging (DBS) technique, used by many commercial systems, considers measurements of this LOS velocity in multiple radial directions in order to estimate horizontal and vertical winds. The method relies on the assumption of homogeneous flow across the region sampled by the beams. Using such a system in inhomogeneous flow, such as wind turbine wakes or complex terrain, will result in errors.

    To quantify the errors expected from such violation of the assumption of horizontal homogeneity, we simulate inhomogeneous flow in the atmospheric boundary layer, notably stably stratified flow past a wind turbine, with a mean wind speed of 6.5 m s-1 at the turbine hub-height of 80 m. This slightly stable case results in 15° of wind direction change across the turbine rotor disk. The resulting flow field is sampled in the same fashion that a lidar samples the atmosphere with the DBS approach, including the lidar range weighting function, enabling quantification of the error in the DBS observations. The observations from the instruments located upwind have small errors, which are ameliorated with time averaging. However, the downwind observations, particularly within the first two rotor diameters downwind from the wind turbine, suffer from errors due to the heterogeneity of the wind turbine wake. Errors in the stream-wise component of the flow approach 30% of the hub-height inflow wind speed close to the rotor disk. Errors in the cross-stream and vertical velocity components are also significant: cross-stream component errors are on the order of 15% of the hub-height inflow wind speed (1.0 m s−1) and errors in the vertical velocity measurement

  16. Quantifying error of lidar and sodar Doppler beam swinging measurements of wind turbine wakes using computational fluid dynamics

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

    Lundquist, J. K.; Churchfield, M. J.; Lee, S.; Clifton, A.

    2015-02-23

    Wind-profiling lidars are now regularly used in boundary-layer meteorology and in applications such as wind energy and air quality. Lidar wind profilers exploit the Doppler shift of laser light backscattered from particulates carried by the wind to measure a line-of-sight (LOS) velocity. The Doppler beam swinging (DBS) technique, used by many commercial systems, considers measurements of this LOS velocity in multiple radial directions in order to estimate horizontal and vertical winds. The method relies on the assumption of homogeneous flow across the region sampled by the beams. Using such a system in inhomogeneous flow, such as wind turbine wakes ormore » complex terrain, will result in errors. To quantify the errors expected from such violation of the assumption of horizontal homogeneity, we simulate inhomogeneous flow in the atmospheric boundary layer, notably stably stratified flow past a wind turbine, with a mean wind speed of 6.5 m s-1 at the turbine hub-height of 80 m. This slightly stable case results in 15° of wind direction change across the turbine rotor disk. The resulting flow field is sampled in the same fashion that a lidar samples the atmosphere with the DBS approach, including the lidar range weighting function, enabling quantification of the error in the DBS observations. The observations from the instruments located upwind have small errors, which are ameliorated with time averaging. However, the downwind observations, particularly within the first two rotor diameters downwind from the wind turbine, suffer from errors due to the heterogeneity of the wind turbine wake. Errors in the stream-wise component of the flow approach 30% of the hub-height inflow wind speed close to the rotor disk. Errors in the cross-stream and vertical velocity components are also significant: cross-stream component errors are on the order of 15% of the hub-height inflow wind speed (1.0 m s−1) and errors in the vertical velocity measurement exceed the actual

  17. Implementation and assessment of turbine wake models in the Weather Research and Forecasting model for both mesoscale and large-eddy simulation

    SciTech Connect (OSTI)

    Singer, M; Mirocha, J; Lundquist, J; Cleve, J

    2010-03-03

    Flow dynamics in large wind projects are influenced by the turbines located within. The turbine wakes, regions characterized by lower wind speeds and higher levels of turbulence than the surrounding free stream flow, can extend several rotor diameters downstream, and may meander and widen with increasing distance from the turbine. Turbine wakes can also reduce the power generated by downstream turbines and accelerate fatigue and damage to turbine components. An improved understanding of wake formation and transport within wind parks is essential for maximizing power output and increasing turbine lifespan. Moreover, the influence of wakes from large wind projects on neighboring wind farms, agricultural activities, and local climate are all areas of concern that can likewise be addressed by wake modeling. This work describes the formulation and application of an actuator disk model for studying flow dynamics of both individual turbines and arrays of turbines within wind projects. The actuator disk model is implemented in the Weather Research and Forecasting (WRF) model, which is an open-source atmospheric simulation code applicable to a wide range of scales, from mesoscale to large-eddy simulation. Preliminary results demonstrate the applicability of the actuator disk model within WRF to a moderately high-resolution large-eddy simulation study of a small array of turbines.

  18. Numerical performance analysis of acoustic Doppler velocity profilers in the wake of an axial-flow marine hydrokinetic turbine

    SciTech Connect (OSTI)

    Richmond, Marshall C.; Harding, Samuel F.; Romero Gomez, Pedro DJ

    2015-09-01

    The use of acoustic Doppler current profilers (ADCPs) for the characterization of flow conditions in the vicinity of both experimental and full scale marine hydrokinetic (MHK) turbines is becoming increasingly prevalent. The computation of a three dimensional velocity measurement from divergent acoustic beams requires the assumption that the flow conditions are homogeneous between all beams at a particular axial distance from the instrument. In the near wake of MHK devices, the mean fluid motion is observed to be highly spatially dependent as a result of torque generation and energy extraction. This paper examines the performance of ADCP measurements in such scenarios through the modelling of a virtual ADCP (VADCP) instrument in the velocity field in the wake of an MHK turbine resolved using unsteady computational fluid dynamics (CFD). This is achieved by sampling the CFD velocity field at equivalent locations to the sample bins of an ADCP and performing the coordinate transformation from beam coordinates to instrument coordinates and finally to global coordinates. The error in the mean velocity calculated by the VADCP relative to the reference velocity along the instrument axis is calculated for a range of instrument locations and orientations. The stream-wise velocity deficit and tangential swirl velocity caused by the rotor rotation lead to significant misrepresentation of the true flow velocity profiles by the VADCP, with the most significant errors in the transverse (cross-flow) velocity direction.

  19. Development and Validation of a New Blade Element Momentum Skewed-Wake Model within AeroDyn: Preprint

    SciTech Connect (OSTI)

    Ning, S. A.; Hayman, G.; Damiani, R.; Jonkman, J.

    2014-12-01

    Blade element momentum methods, though conceptually simple, are highly useful for analyzing wind turbines aerodynamics and are widely used in many design and analysis applications. A new version of AeroDyn is being developed to take advantage of new robust solution methodologies, conform to a new modularization framework for National Renewable Energy Laboratory's FAST, utilize advanced skewed-wake analysis methods, fix limitations with previous implementations, and to enable modeling of highly flexible and nonstraight blades. This paper reviews blade element momentum theory and several of the options available for analyzing skewed inflow. AeroDyn implementation details are described for the benefit of users and developers. These new options are compared to solutions from the previous version of AeroDyn and to experimental data. Finally, recommendations are given on how one might select from the various available solution approaches.

  20. Investigating wind turbine impacts on near-wake flow using profiling Lidar data and large-eddy simulations with an actuator disk model

    SciTech Connect (OSTI)

    Mirocha, Jeffrey D.; Rajewski, Daniel A.; Marjanovic, Nikola; Lundquist, Julie K.; Kosovic, Branko; Draxl, Caroline; Churchfield, Matthew J.

    2015-08-27

    In this study, wind turbine impacts on the atmospheric flow are investigated using data from the Crop Wind Energy Experiment (CWEX-11) and large-eddy simulations (LESs) utilizing a generalized actuator disk (GAD) wind turbine model. CWEX-11 employed velocity-azimuth display (VAD) data from two Doppler lidar systems to sample vertical profiles of flow parameters across the rotor depth both upstream and in the wake of an operating 1.5 MW wind turbine. Lidar and surface observations obtained during four days of July 2011 are analyzed to characterize the turbine impacts on wind speed and flow variability, and to examine the sensitivity of these changes to atmospheric stability. Significant velocity deficits (VD) are observed at the downstream location during both convective and stable portions of four diurnal cycles, with large, sustained deficits occurring during stable conditions. Variances of the streamwise velocity component, σu, likewise show large increases downstream during both stable and unstable conditions, with stable conditions supporting sustained small increases of σu , while convective conditions featured both larger magnitudes and increased variability, due to the large coherent structures in the background flow. Two representative case studies, one stable and one convective, are simulated using LES with a GAD model at 6 m resolution to evaluate the compatibility of the simulation framework with validation using vertically profiling lidar data in the near wake region. Virtual lidars were employed to sample the simulated flow field in a manner consistent with the VAD technique. Simulations reasonably reproduced aggregated wake VD characteristics, albeit with smaller magnitudes than observed, while σu values in the wake are more significantly underestimated. The results illuminate the limitations of using a GAD in combination with coarse model resolution in the simulation of near wake physics, and validation thereof using VAD data.

  1. Investigating wind turbine impacts on near-wake flow using profiling Lidar data and large-eddy simulations with an actuator disk model

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

    Mirocha, Jeffrey D.; Rajewski, Daniel A.; Marjanovic, Nikola; Lundquist, Julie K.; Kosovic, Branko; Draxl, Caroline; Churchfield, Matthew J.

    2015-08-27

    In this study, wind turbine impacts on the atmospheric flow are investigated using data from the Crop Wind Energy Experiment (CWEX-11) and large-eddy simulations (LESs) utilizing a generalized actuator disk (GAD) wind turbine model. CWEX-11 employed velocity-azimuth display (VAD) data from two Doppler lidar systems to sample vertical profiles of flow parameters across the rotor depth both upstream and in the wake of an operating 1.5 MW wind turbine. Lidar and surface observations obtained during four days of July 2011 are analyzed to characterize the turbine impacts on wind speed and flow variability, and to examine the sensitivity of thesemore » changes to atmospheric stability. Significant velocity deficits (VD) are observed at the downstream location during both convective and stable portions of four diurnal cycles, with large, sustained deficits occurring during stable conditions. Variances of the streamwise velocity component, σu, likewise show large increases downstream during both stable and unstable conditions, with stable conditions supporting sustained small increases of σu , while convective conditions featured both larger magnitudes and increased variability, due to the large coherent structures in the background flow. Two representative case studies, one stable and one convective, are simulated using LES with a GAD model at 6 m resolution to evaluate the compatibility of the simulation framework with validation using vertically profiling lidar data in the near wake region. Virtual lidars were employed to sample the simulated flow field in a manner consistent with the VAD technique. Simulations reasonably reproduced aggregated wake VD characteristics, albeit with smaller magnitudes than observed, while σu values in the wake are more significantly underestimated. The results illuminate the limitations of using a GAD in combination with coarse model resolution in the simulation of near wake physics, and validation thereof using VAD data.« less

  2. Assessing world energy in the wake of the Iran/Iraq war: an oil shortage proves elusive. [Monograph

    SciTech Connect (OSTI)

    Randol, W.L.; Verleger, P.K. Jr.; Clayman, M.

    1981-01-01

    A reassessment of world energy supplies was made in the wake of curtailed exports during the Iran/Iraq war and the corresponding increase in world oil prices, the drop in oil consumption, the widening economic recession, and US decontrol of oil. The report concludes that present worldwide levels of oil production are adequate to satisfy projected levels of consumption through 1981. This leaves the world energy system in balance even if oil exports from Iran and Iraq remain at minimal levels for the year. Past overestimation of demand makes it more likely that this year's consumption will fall short of the projection. The way in which Saudi Arabia's output is cut will be the key to oil pricing in 1981, the authors feel, but the likely approach will be a gradual reduction in production that will allow the Saudis to regain control of OPEC. The effects of a receding demand for oil have been intensified by high US interest rates and the spreading recession. The effect of immediate decontrol of petroleum is likely to compound the trend for reduced consumption and a corresponding increase in efficiency. 2 figures, 2 tables.

  3. Wake Imaging Measurement System

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

    Imaging Measurement System - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced

  4. Wake Steering Experiment

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

    Steering Experiment - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Energy Defense Waste Management Programs Advanced Nuclear

  5. Wake Imaging Measurement System

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

    Imaging Measurement System - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us ... Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear ...

  6. SNL Wake Imaging System Solves Wind Turbine Wake Formation Mysteries...

    Broader source: Energy.gov (indexed) [DOE]

    Illustration showing a utility-scale wind turbine in a field. A square brown steel shed ... a green triangle) that travels from the shed to above the turbine downwind of the turbine. ...

  7. Soderberg_RecontresDeVietnam

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

    1. FIG. 2: The antineutrino mode (top) and neutrino QE MiniBooNE MiniBooNE MicroBooNE: Physics 16 * Prove effectiveness of electrongamma separation technique (e.g. - using dE...

  8. Manufacturing's Wake-Up Call

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

    ... Source: Bureau of Labor Statistics, Booz & Company GDP increases to as much as 25 ... flow, usage of materials and energy, energy conservation, and other components of productivity. ...

  9. Vietnam: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    MWhyear 66 2008 NREL Coal Reserves 165.35 Million Short Tons 53 2008 EIA Natural Gas Reserves 680,000,000,000 Cubic Meters (cu m) 31 2010 CIA World Factbook Oil Reserves...

  10. Synchrotron Radiation Wake in Free Space

    SciTech Connect (OSTI)

    Stupakov, G.V.; /SLAC

    2011-08-31

    In this paper, we derive the transverse radiation force of a bunch of ultrarelativistic charged particles coherently radiating in free space assuming that the bending radius is much larger than the beam dimensions. In contrast to a similar recent study, where the authors decompose the total transverse force and find only a part that is responsible for the distortion of the beam orbit, we derive a full expression for the force and leave the issues of the beam dynamics for a separate consideration. Another approach to the calculation of the transverse force has been previously developed. In many cases considered in this paper, the calculations are extremely cumbersome; they were systematically performed with the use of symbolic engine of the computer program MATHEMATICA.

  11. TWO-CHANNEL DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-05-30

    Experimental results are reported for test beam acceleration and deflection in a two-channel, cm-scale, rectangular dielectric-lined wakefield accelerator structure energized by a 14-MeV drive beam. The dominant waveguide mode of the structure is at {approx}30 GHz, and the structure is configured to exhibit a high transformer ratio ({approx}12:1). Accelerated bunches in the narrow secondary channel of the structure are continuously energized via Cherenkov radiation that is emitted by a drive bunch moving in the wider primary channel. Observed energy gains and losses, transverse deflections, and changes in the test bunch charge distribution compare favorably with predictions of theory.

  12. In the wake of the Exxon Valdez

    SciTech Connect (OSTI)

    Davidson, A.

    1990-01-01

    On March 24, 1989, the oil tanker Exxon Valdez went aground on Bligh Reef in Prince William Sound, Alaska, releasing more than ten million gallons of oil. This book begins with a dramatic, minute-by-minute account of the wreck itself and the woefully ineffective oil spill response plans. It explores the reactions and interactions of the oil industry and government officials. It includes interviews of Exxon executives, state and federal decision-makers, environmental scientists, and Native villagers. Drawing on these exclusive accounts plus the myriad public documents generated by the disaster, a compelling account of an environmental crisis beyond control and its devastating toll on Alaska's people, wildlife, and landscape is presented.

  13. Technique for ship/wake detection

    DOE Patents [OSTI]

    Roskovensky, John K.

    2012-05-01

    An automated ship detection technique includes accessing data associated with an image of a portion of Earth. The data includes reflectance values. A first portion of pixels within the image are masked with a cloud and land mask based on spectral flatness of the reflectance values associated with the pixels. A given pixel selected from the first portion of pixels is unmasked when a threshold number of localized pixels surrounding the given pixel are not masked by the cloud and land mask. A spatial variability image is generated based on spatial derivatives of the reflectance values of the pixels which remain unmasked by the cloud and land mask. The spatial variability image is thresholded to identify one or more regions within the image as possible ship detection regions.

  14. Wake Electric Membership Corp | Open Energy Information

    Open Energy Info (EERE)

    North Carolina Service Territory: North Carolina Phone Number: 919.863.6499 or toll free 800.743.3155 Website: www.wemc.com Facebook: https:ebill.wemc.comwoViewer...

  15. First Wake Data Captured During Wake Steering Experiment at the SWiFT

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

    Emergencies First Responders NNSA's first responders include the Radiological Assistance Program (RAP) and the Search Response Team (SRT). These teams provide specialized national-level first responder technical and operational capabilities, and conduct specialized operations, during the initial phases of a response to a radiological or nuclear incident in coordination with federal, state and local authorities. The first responders conduct detection, identification, and analysis of radiological

  16. Vietnam-Facilitating Implementation and Readiness for Mitigation...

    Open Energy Info (EERE)

    six to eight developing countries to strengthen their national low carbon development strategies and get a "quick start" on NAMAs. The focus will be on reducing emissions of...

  17. Vietnam-The World Bank Partnership for Market Readiness (PMR...

    Open Energy Info (EERE)

    Morocco Implement climate change mitigation policy as part of National Plan against Global Warming. PMR Support: Establish MRV framework. Identify and develop crediting NAMAs...

  18. Vietnam-Danish Government Baseline Workstream | Open Energy Informatio...

    Open Energy Info (EERE)

    Government Partner Danish Ministry for Climate, Energy, and Building; The Danish Energy Agency Sector Energy Topics Implementation, Low emission development planning Program...

  19. Vietnam-Strengthening Planning Capacity for Low Carbon Growth...

    Open Energy Info (EERE)

    Growth in Developing Asia AgencyCompany Organization Asian Development Bank Partner Japan, United Kingdom Sector Climate, Energy Focus Area Non-renewable Energy, Buildings,...

  20. Vietnam-Integrated Action Plan to Reduce Vehicle Emissions |...

    Open Energy Info (EERE)

    and reduce air pollution. Furthermore, they are required to ensure that Viet Nam's air quality meets the average standards set by the Association of Southeast Asian Nation...

  1. Vietnam-EU-UNDP Low Emission Capacity Building Programme (LECBP...

    Open Energy Info (EERE)

    Programme (UNDP), German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU), Australian Department of Climate Change and Energy Efficiency (DCCEE),...

  2. Vietnam-The Mitigation Action Implementation Network (MAIN) ...

    Open Energy Info (EERE)

    of Energy Thailand, Ministry of Industry Thailand, Ministry of Natural Resources and Environment Thailand, Pollution Control Department, Ministry of Natural Resources and...

  3. Vietnam-Development Policy Operation (DPO) Financing | Open Energy...

    Open Energy Info (EERE)

    Policy Operation Financing AgencyCompany Organization France Agency of Development (AFD) Partner JICA, CIDA, WB, Korean Exim, AusAid Sector Climate Focus Area Non-renewable...

  4. Vietnam-Low Emissions Asian Development (LEAD) Program | Open...

    Open Energy Info (EERE)

    the growth of greenhouse gas emissions. The LEAD program supports and enhances country-led development programs, plans, and policies, and complements efforts of other...

  5. Vietnam-World Bank Climate Projects | Open Energy Information

    Open Energy Info (EERE)

    electricity access will be improved by upgrading, and strengthening the 110 KV sub-transmission line, and substations, restoring five existing hydropower plants, and, by...

  6. Vietnam-NAMA Programme for the Construction Sector in Asia |...

    Open Energy Info (EERE)

    United Nations Environment Programme (UNEP) Sector Climate Focus Area Renewable Energy, Buildings, Industry Topics Low emission development planning, -LEDS, -NAMA, Market...

  7. Vietnam Research Center for Energy and Environment | Open Energy...

    Open Energy Info (EERE)

    of renewable and clean energy development and energy efficiency. RCEE focuses on climate change issues too, like policies on clean development mechanism (CDM), and developing...

  8. Vietnam-Enhancing Capacity for Low Emission Development Strategies...

    Open Energy Info (EERE)

    illustrates the U.S. perspective on LEDS: Integrated development goals and objectives, national greenhouse gas inventory, and economic and resource data Long-term projections of...

  9. Vietnam-Strengthening Public and Private Climate Finance in Asia...

    Open Energy Info (EERE)

    to support climate-resilient development in the developing world. Mitigation investment is substantial in parts of Asia, but lacking elsewhere; adaptation investment flows...

  10. Multizone subsea completions in the Dai Hung field, Vietnam

    SciTech Connect (OSTI)

    Lay, K.R.

    1996-09-01

    The early production phase of the Dai Hung field development resulted in the drilling and completion of five subsea wells. Because of the complex nature of the reservoirs, selective multizone completions were installed for effective reservoir data acquisition and reservoir management. The downhole completion designs used equipment that was primarily of existing proven design and downhole equipment installation was successfully achieved in a single trip. Ongoing reservoir management will be aided by the use of a subsea wireline system to facilitate data acquisition.

  11. Brief: Multizone subsea completions in the Dai Hung field, Vietnam

    SciTech Connect (OSTI)

    Lay, K.R.

    1996-04-01

    The early production phase of the Dai Hung field development involved drilling and completion of five subsea wells. Owing to the complex nature of the reservoirs, selective multizone completions were installed for effective reservoir data acquisition and reservoir management. Downhole completion designs used equipment that was primarily of existing proven design, and downhole equipment was installed in a single trip. Ongoing reservoir management will be aided by use of a subsea wireline system to facilitate data acquisition.

  12. Vietnam-Lowering Emissions in Asia's Forests (LEAF) | Open Energy...

    Open Energy Info (EERE)

    assessing, improving, and implementing REDD+- related forest policies; improving forest management; and encouraging equitable sharing of REDD+ benefits. The program will tailor...

  13. Vietnam-Clean Technology Fund (CTF) | Open Energy Information

    Open Energy Info (EERE)

    and Development, Inter-American Development Bank, World Bank Sector Climate, Energy Focus Area Energy Efficiency, Geothermal, Transportation Topics Background analysis,...

  14. Smart Companies "Wake up" Night Shift Workers Make More Mistakes...

    Office of Environmental Management (EM)

    to Accidents A study from Circadian Technologies, http:www.circadian.commediaPress.html, a consulting firm which specializes in advising the nation's largest companies on how...

  15. Wake County, North Carolina: Energy Resources | Open Energy Informatio...

    Open Energy Info (EERE)

    Solutions Formerly LED Lighting Fixtures LLF Eaton Powerware INI Power Systems Methane Power Inc Microcell Corp North Carolina State Energy Office North Carolina State...

  16. Radar imagery from the 1994 Lock Linnhe ship wake experiment

    SciTech Connect (OSTI)

    Mullenhoff, C.J.; Lehman, S.K.; Jones, H.

    1994-11-15

    The 1994 Loch Linnhe radar ocean imaging trials were held from September 4 through September 17. Two ships were used: the R.V. Colonel Templer, and the RMAS Collie. Thorn EMI, Inc., fielded a dual band, dual polarization radar on a hillside overlooking the loch. A primary purpose of the experiment was to obtain highly visible images of ship generated internal waves. Presented here is imagery for a few of the good ship runs, as well as a study of the environment of the visibility of ship generated internal waves.

  17. Wake fields effects for the eRHIC project

    SciTech Connect (OSTI)

    Fedotov A. V.; Belomestnykh, S.; Kayran, D.; Litvinenko, V.; Ptitsyn, V.

    2012-05-20

    An Energy Recovery Linac (ERL) with a high peak electron bunch current is proposed for the Electron-Ion collider (eRHIC) project at the Brookhaven National Laboratory. The present design is based on the multi-pass electron beam transport in existing tunnel of the Relativistic Heavy Ion Collider (RHIC). As a result of a high peak current and a very long beam transport, consideration of various collective beam dynamics effects becomes important. Here we summarize effects of the coherent synchrotron radiation, resistive wall, accelerating cavities and wall roughness on the resulting energy spread and energy loss for several scenarios of the eRHIC project.

  18. Mesurement of the Decelerating Wake in a Plasma Wakefield Accelerator...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Country of Publication: United States Language: English Subject: 43 PARTICLE ACCELERATORS; ACCELERATION; ACCELERATORS; ELECTRON BEAMS; ELECTRONS; METERS; ...

  19. Wake Forest, North Carolina: Energy Resources | Open Energy Informatio...

    Open Energy Info (EERE)

    Forest, North Carolina: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 35.9798734, -78.5097228 Show Map Loading map... "minzoom":false,"mappin...

  20. Mesurement of the Decelerating Wake in a Plasma Wakefield Accelerator...

    Office of Scientific and Technical Information (OSTI)

    Publication Date: 2008-09-24 OSTI Identifier: 938638 Report Number(s): SLAC-PUB-13390 TRN: ... Concepts Workshop (AAC08), Santa Cruz, California, 27 Jul - 2 Aug 2008 Research ...

  1. Parallel computation of transverse wakes in linear colliders

    SciTech Connect (OSTI)

    Zhan, Xiaowei; Ko, Kwok

    1996-11-01

    SLAC has proposed the detuned structure (DS) as one possible design to control the emittance growth of long bunch trains due to transverse wakefields in the Next Linear Collider (NLC). The DS consists of 206 cells with tapering from cell to cell of the order of few microns to provide Gaussian detuning of the dipole modes. The decoherence of these modes leads to two orders of magnitude reduction in wakefield experienced by the trailing bunch. To model such a large heterogeneous structure realistically is impractical with finite-difference codes using structured grids. The authors have calculated the wakefield in the DS on a parallel computer with a finite-element code using an unstructured grid. The parallel implementation issues are presented along with simulation results that include contributions from higher dipole bands and wall dissipation.

  2. Horizontal-Axis Wind Turbine Wake Sensitivity to Different Blade...

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

    U inflow angle at blade section relative to plane of rotation + , degrees angular velocity of rotor, rads SW iF T Scaled Wind Farm Technology x time average of...

  3. Sandia Wake-Imaging System Successfully Deployed at Scaled Wind...

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

    ... a full-scale field demonstration at the Sandia Scaled Wind Farm Technology (SWiFT) facility in Lubbock, Texas, in July. This successful field demonstration was a culmination of ...

  4. Vietnam-GTZ RE Policy and Wind Power Development Project | Open...

    Open Energy Info (EERE)

    on behalf of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) Partner Ministry of Industry and Trade (MoIT), The Electricity...

  5. Opportunities and Challenges to Scaling-up Wind Power in Vietnam...

    Open Energy Info (EERE)

    AgencyCompany Organization Asian Development Bank Sector Energy Focus Area Renewable Energy, Wind Topics Co-benefits assessment, Market analysis, Pathways analysis, Background...

  6. Vietnam-Low Carbon Asia Research Network (LoCARNet) | Open Energy...

    Open Energy Info (EERE)

    Energy, Land Focus Area Agriculture, Biomass, Buildings, Economic Development, Energy Efficiency, Forestry, Geothermal, Greenhouse Gas, Hydrogen, Industry, Land Use, People and...

  7. Vietnam-EC-LEDS in the Agriculture Sector | Open Energy Information

    Open Energy Info (EERE)

    Sector Climate, Land Focus Area Agriculture, Economic Development, Greenhouse Gas, Land Use Topics Adaptation, Implementation, Low emission development planning, -LEDS,...

  8. Smart Companies “Wake up” Night Shift Workers Make More Mistakes & More Prone to Accidents

    Broader source: Energy.gov [DOE]

    A study from Circadian Technologies, http://www.circadian.com/media/Press.html, a consulting firm which specializes in advising the nation's largest companies on how to manage their extended-hours operations, estimates that maintaining the practice may be costing companies a steep $206 billion annually -- $8,600 per worker.

  9. Study of electron trapping by a transversely ellipsoidal bubble in the laser wake-field acceleration

    SciTech Connect (OSTI)

    Cho, Myung-Hoon; Kim, Young-Kuk; Hur, Min Sup

    2013-09-15

    We present electron trapping in an ellipsoidal bubble which is not well explained by the spherical bubble model by [Kostyukov et al., Phys. Rev. Lett. 103, 175003 (2009)]. The formation of an ellipsoidal bubble, which is elongated transversely, frequently occurs when the spot size of the laser pulse is large compared to the plasma wavelength. First, we introduce the relation between the bubble size and the field slope inside the bubble in longitudinal and transverse directions. Then, we provide an ellipsoidal model of the bubble potential and investigate the electron trapping condition by numerical integration of the equations of motion. We found that the ellipsoidal model gives a significantly less restrictive trapping condition than that of the spherical bubble model. The trapping condition is compared with three-dimensional particle-in-cell simulations and the electron trajectory in test potential simulations.

  10. A Minnesota Blizzard Provides Insight into Utility-Scale Wind Turbine Wakes

    Broader source: Energy.gov [DOE]

    Starting in 2012, researchers tried placing spotlights downwind from the 2.5-megawatt (MW) wind turbine in Rosemount, Minnesota. The research team was attempting to study turbulent airflow around a turbine in the field.

  11. Observation of Magnetized Soliton Remnants in the Wake of Intense Laser Pulse Propagation through Plasmas

    SciTech Connect (OSTI)

    Romagnani, L.; Bigongiari, A.; Kar, S.; Borghesi, M.; Bulanov, S. V.; Esirkepov, T. Zh.; Cecchetti, C. A.; Galimberti, M.; Jung, R.; Osterholz, J.; Willi, O.; Liseykina, T. V.; Macchi, A.; Pegoraro, F.

    2010-10-22

    Slowly evolving, regularly spaced patterns have been observed in proton projection images of plasma channels drilled by intense (> or approx. 10{sup 19} W cm{sup -2}) short ({approx}1 ps) laser pulses propagating in an ionized gas jet. The nature and geometry of the electromagnetic fields generating such patterns have been inferred by simulating the laser-plasma interaction and the following plasma evolution with a two-dimensional particle-in-cell code and the probe proton deflections by particle tracing. The analysis suggests the formation of rows of magnetized soliton remnants, with a quasistatic magnetic field associated with vortexlike electron currents resembling those of magnetic vortices.

  12. In the wake of high-profile battery fires, a safer approach emerges...

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

    Credit:MartinPetitiStockThinkstock As news reports of lithium-ion battery (LIB) fires in Boeing Dreamliner planes and Tesla electric cars remind us, these batteries - which are ...

  13. Solar Decathlon Team Leading the Way Toward Sustainable Living, Even in the Wake of Disasters

    Broader source: Energy.gov [DOE]

    For this year’s Solar Decathlon, the University of Illinois at Urbana-Champaign is returning to the National Mall with the Re_home, which offers a more sustainable housing solution for communities following a natural disaster.

  14. Analysis of the three-dimensional structure of a bubble wake using PIV and Galilean decomposition

    SciTech Connect (OSTI)

    Hassan, Y.A.; Schmidl, W.D.; Ortiz-Villafuerte, J.; Scharf, J.R.

    1999-07-01

    Bubbly flow plays a key role in a variety of natural and industrial processes. An accurate and complete description of the phase interactions in two-phase bubbly flow is not available at this time. These phase interactions are, in general, always three-dimensional and unsteady. Therefore, measurement techniques utilized to obtain qualitative and quantitative data from two-phase flow should be able to acquire transient and three-dimensional data, in order to provide information to test theoretical models and numerical simulations. Even for dilute bubble flows, in which bubble interaction is at a minimum, the turbulent motion of the liquid generated by the bubble is yet to be completely understood. For many years, the design of systems with bubbly flows was based primarily on empiricism. Dilute bubbly flows are an extension of single bubble dynamics, and therefore improvements in the description and modeling of single bubble motion, the flow field around the bubble, and the dynamical interactions between the bubble and the flow will consequently improve bubbly flow modeling. The improved understanding of the physical phenomena will have far-reaching benefits in upgrading the operation and efficiency of current processes and in supporting the development of new and innovative approaches. A stereoscopic particle image velocimetry measurement of the flow generated by the passage of a single air-bubble rising in stagnant water, in a circular pipe is presented. Three-dimensional velocity fields within the measurement zone were obtained. Ensemble-averaged instantaneous velocities for a specific bubble path were calculated and interpolated to obtain mean three-dimensional velocity fields. A Galilean velocity decomposition is used to study the vorticity generated in the flow.

  15. Waking the sleeping giant: Introducing new heat exchanger technology into the residential air-conditioning marketplace

    SciTech Connect (OSTI)

    Chapp, T.; Voss, M.; Stephens, C.

    1998-07-01

    The Air Conditioning Industry has made tremendous strides in improvements to the energy efficiency and reliability of its product offerings over the past 40 years. These improvement can be attributed to enhancements of components, optimization of the energy cycle, and modernized and refined manufacturing techniques. During this same period, energy consumption for space cooling has grown significantly. In January of 1992, the minimum efficiency requirement for central air conditioning equipment was raised to 10 SEER. This efficiency level is likely to increase further under the auspices of the National Appliance Energy Conservation Act (NAECA). A new type of heat exchanger was developed for air conditioning equipment by Modine Manufacturing Company in the early 1990's. Despite significant advantages in terms of energy efficiency, dehumidification, durability, and refrigerant charge there has been little interest expressed by the air conditioning industry. A cooperative effort between Modine, various utilities, and several state energy offices has been organized to test and demonstrate the viability of this heat exchanger design throughout the nation. This paper will review the fundamentals of heat exchanger design and document this simple, yet novel technology. These experiences involving equipment retrofits have been documented with respect to the performance potential of air conditioning system constructed with PF{trademark} Heat Exchangers (generically referred to as microchannel heat exchangers) from both an energy efficiency as well as a comfort perspective. The paper will also detail the current plan to introduce 16 to 24 systems into an extended field test throughout the US which commenced in the Fall of 1997.

  16. Wake potentials and impedances for the ATA (Advanced Test Accelerator) induction cell

    SciTech Connect (OSTI)

    Craig, G.D.

    1990-09-04

    The AMOS Wakefield Code is used to calculate the impedances of the induction cell used in the Advanced Test Accelerator (ATA) at Livermore. We present the wakefields and impedances for multipoles m = 0, 1 and 2. The ATA cell is calculated to have a maximum transverse impedance of approximately 1000 {Omega}/m at 875 MHz with a quality factor Q = 5. The sensitivity of the impedance spectra to modeling variations is discussed.

  17. The Facility for 500 MeV Plasma Wake-Field Acceleration Experiments at Budker INP

    SciTech Connect (OSTI)

    Petrenko, A. V.; Lotov, K. V.; Logatchov, P. V.; Burdakov, A. V.

    2010-11-04

    The experimental PWFA facility currently under construction at the Budker INP is described. The objective is to use electron and positron beams extracted from the VEPP-5 damping ring in PWFA experiments. Due to longitudinal beam compression many PWFA schemes including the efficient blowout regime as well as multibunch regime can be studied. The simulations of beam dynamics in the facility are presented. Also we propose a simple technique for longitudinal beam slicing using dipole kickers and collimator in the damping ring.

  18. A VERY DEEP CHANDRA OBSERVATION OF A1795: THE COLD FRONT AND COOLING WAKE

    SciTech Connect (OSTI)

    Ehlert, Steven; McDonald, Michael; Miller, Eric D.; Bautz, Mark W.; David, Laurence P.

    2015-02-01

    We present a new analysis of very deep Chandra observations of the galaxy cluster A1795. Utilizing nearly 750 ks of net ACIS imaging, we are able to resolve the thermodynamic structure of the intracluster medium (ICM) on length scales of ∼1 kpc near the cool core. We find several previously unresolved structures, including a high pressure feature to the north of the Brightest Cluster Galaxy (BCG) that appears to arise from the bulk motion of A1795's cool core. To the south of the cool core, we find low temperature (∼3 keV), diffuse ICM gas extending for distances of ∼50 kpc spatially coincident with previously identified filaments of Hα emission. Gas at similar temperatures is also detected in adjacent regions without any Hα emission. The X-ray gas coincident with the Hα filament has been measured to be cooling spectroscopically at a rate of ∼1 M{sub ⊙} yr{sup −1}, consistent with measurements of the star formation rate in this region as inferred from ultraviolet (UV) observations, suggesting that the star formation in this filament as inferred by its Hα and UV emission can trace its origin to the rapid cooling of dense, X-ray emitting gas. The Hα filament is not a unique site of cooler ICM, however, as ICM at similar temperatures and even higher metallicities not cospatial with Hα emission is observed just to the west of the Hα filament, suggesting that it may have been uplifted by A1795's central active galaxy. Further simulations of cool core sloshing and active galactic nucleus feedback operating in concert with one another will be necessary to understand how such a dynamic cool core region may have originated and why the Hα emission is so localized with respect to the cool X-ray gas.

  19. The Oil Pollution Act of 1990: Legislation in the wake of a crisis

    SciTech Connect (OSTI)

    Grumbles, B.H.; Manley, J.M.

    1995-12-31

    The pattern is nothing new. Congress, like any other institution, needs nudging-sometimes gentle, sometimes jolting-before it responds. An environmental crisis prompts a congressional reaction, sometimes an overreaction. The discovery of contamination at Love Canal prompted enactment of Superfund; the disaster at Bhopal, India, led to the Emergency Planning and Community Right to Know Act; and the collision of the Exxon Valdez brought about the enactment of the Oil Pollution Act of 1990. For better or for worse, the pattern of environmental crisis and legislative response remains. March 24, 1989, marked the beginning of a new age in federal and state oil spill law. After the Exxon Valdez ran aground on Bligh reef and spewed 11 million gallons of crude oil into Prince William Sound, Alaska congressional debate on comprehensive federal legislation would never be the same. The stalemate that characterized previous congressional efforts seemed to disappear overnight. Major differences between the two chambers were either eliminated or reduced, and only 4 major issues had to be negotiated: international protocols; technical requirements relating to double hulls; cargo owner liability; state and private industry roles in oil spill contingency planning, response and cleanup efforts. This article discusses the legal manuvering and major provisions of the Oil Pollution Act of 1990.

  20. ARM - Lesson Plans: Effects of Solar Radiation on Land and Sea

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

    However, on some of the larger islands of Melanesia (Fiji, Vanuatu, Solomons, and Papua New Guinea), the effect of land and sea on temperature is noticeable, particularly on fine ...

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

    VietNam 2004 5th Rencontres du Vietnam Particle Physics and Astrophysics Conference D. Schmitz Status of MiniBooNE

  2. Addressing the Growing Cancer Burden in the Wake of the AIDS Epidemic in Botswana: The BOTSOGO Collaborative Partnership

    SciTech Connect (OSTI)

    Efstathiou, Jason A.; Bvochora-Nsingo, Memory; Gierga, David P.; Alphonse Kayembe, Mukendi K.; Mmalane, Mompati; Russell, Anthony H.; Paly, Jonathan J.; Brown, Carolyn; Musimar, Zola; Abramson, Jeremy S.; Bruce, Kathy A.; Karumekayi, Talkmore; Clayman, Rebecca; Hodgeman, Ryan; Kasese, Joseph; Makufa, Remigio; Bigger, Elizabeth; Suneja, Gita; Busse, Paul M.; and others

    2014-07-01

    Botswana has experienced a dramatic increase in HIV-related malignancies over the past decade. The BOTSOGO collaboration sought to establish a sustainable partnership with the Botswana oncology community to improve cancer care. This collaboration is anchored by regular tumor boards and on-site visits that have resulted in the introduction of new approaches to treatment and perceived improvements in care, providing a model for partnership between academic oncology centers and high-burden countries with limited resources.

  3. Secretary Chu Thanks Utility Staff and Line Workers For Their Efforts to Restore Power in the Wake of Hurricane Sandy

    Broader source: Energy.gov [DOE]

    As utility companies continue to work to restore power outages, Secretary Chu stopped by Pepco yesterday to personally thank the workers for their hard work.

  4. ASEAN-IEA Activities | Open Energy Information

    Open Energy Info (EERE)

    Policiesdeployment programs, Technology characterizations Resource Type Workshop, Training materials Country Indonesia, Malaysia, Singapore, Thailand, Philippines, Vietnam,...

  5. Red Sun Energy | Open Energy Information

    Open Energy Info (EERE)

    Red Sun Energy Place: Long An Province, Vietnam Product: A Vietnam-based PV module manufacturer References: Red Sun Energy1 This article is a stub. You can help OpenEI by...

  6. Regional nonprofits receive sizeable monetary boost

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

    deserved as a result of that war's widespread unpopularity at the time. "A lot of New Mexicans served in Vietnam," Hopwood noted. "The very first soldier who fell in Vietnam, Turk...

  7. Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code: Preprint

    SciTech Connect (OSTI)

    Maniaci, D. C.; Li, Y.

    2012-04-01

    This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. It summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30 degrees of yaw.

  8. Investigating the Influence of the Added Mass Effect to Marine Hydrokinetic Horizontal-Axis Turbines Using a General Dynamic Wake Wind Turbine Code

    SciTech Connect (OSTI)

    Maniaci, D. C.; Li, Y.

    2011-10-01

    This paper describes a recent study to investigate the applicability of a horizontal-axis wind turbine (HAWT) structural dynamics and unsteady aerodynamics analysis program (FAST and AeroDyn respectively) to modeling the forces on marine hydrokinetic (MHK) turbines. This paper summarizes the added mass model that has been added to AeroDyn. The added mass model only includes flow acceleration perpendicular to the rotor disc, and ignores added mass forces caused by blade deflection. A model of the National Renewable Energy Laboratory's (NREL) Unsteady Aerodynamics Experiment (UAE) Phase VI wind turbine was analyzed using FAST and AeroDyn with sea water conditions and the new added mass model. The results of this analysis exhibited a 3.6% change in thrust for a rapid pitch case and a slight change in amplitude and phase of thrust for a case with 30{sup o} of yaw.

  9. UNEP-Risoe-Economics of GHG Limitations: Country Study Series...

    Open Energy Info (EERE)

    Gas Limitations1 Country study series: Argentina, Ecuador, Estonia, Hungary, Indonesia, Mauritius, Senegal, Vietnam Parallel country studies: Botswana, Tanzania, Zambia...

  10. Asian Development Outlook 2010 | Open Energy Information

    Open Energy Info (EERE)

    Turkmenistan, Uzbekistan, China, South Korea, Mongolia, Afghanistan, Bangladesh, Bhutan, India, Maldives, Pakistan, Sri Lanka, Nepal, Cambodia, Indonesia, Malaysia, Laos, Vietnam,...

  11. FLORIS

    Energy Science and Technology Software Center (OSTI)

    2014-05-11

    FLORIS is an engineering model of wind turbine wake interactions which accounts for the effects of turbines on the flow through the creation of wakes an accounting for both velocity deficit and wake redirection through yaw

  12. Sandia Energy Wind Energy

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

    ss-voucher-pilot-opensfeed 0 Sandia Wake-Imaging System Successfully Deployed at Scaled Wind Farm Technology Facility http:energy.sandia.govsandia-wake-imaging-system-successf...

  13. Sandia Energy Wind News

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

    Sandia Wake-Imaging System Successfully Deployed at Scaled Wind Farm Technology Facility http:energy.sandia.govsandia-wake-imaging-system-successfully-deployed-at-scaled-wind-fa...

  14. Comments on: SWiFT Facility Prepared for More-Efficient Operations...

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

    swift-facility-prepared-for-more-efficient-operations-advanced-turbine-turbine-wake-interaction-control-research...

  15. Wakefields of Sub-Picosecond Electron Bunches

    SciTech Connect (OSTI)

    Bane, Karl L.F.; /SLAC

    2006-04-19

    We discuss wakefields excited by short bunches in accelerators. In particular, we review some of what has been learned in recent years concerning diffraction wakes, roughness impedance, coherent synchrotron radiation wakes, and the resistive wall wake, focusing on analytical solutions where possible. As examples, we apply formulas for these wakes to various parts of the Linac Coherent Light Source (LCLS) project. The longitudinal accelerator structure wake of the SLAC linac is an important ingredient in the LCLS bunch compression process. Of the wakes in the undulator region, the dominant one is the resistive wall wake of the beam pipe.

  16. Analysis of Technology Transfer in CDM Projects | Open Energy...

    Open Energy Info (EERE)

    countries, including Bolivia, Ecuador, Guatemala, Honduras, Indonesia, Kenya, Malaysia, Mexico, Pakistan, South Africa, Sri Lanka, Thailand and Vietnam and significantly lower...

  17. LEDSGP/about | Open Energy Information

    Open Energy Info (EERE)

    Democratic Republic of Congo Department of Science, Education, Natural Resources & Environment, Ministry of Planning and Investment of Vietnam European Commission German Agency...

  18. File:NREL-asia-tilt.pdf | Open Energy Information

    Open Energy Info (EERE)

    Countries Bhutan, China, Nepal, Mongolia, India, North Korea, South Korea, Vietnam, Laos, Thailand, Cambodia, Philippines, Bangladesh UN Region Southern Asia, Eastern Asia,...

  19. File:NREL-asia-dir.pdf | Open Energy Information

    Open Energy Info (EERE)

    Countries Bhutan, China, Nepal, Mongolia, India, North Korea, South Korea, Vietnam, Laos, Thailand, Cambodia, Philippines, Bangladesh UN Region Southern Asia, Eastern Asia,...

  20. File:NREL-asia-glo.pdf | Open Energy Information

    Open Energy Info (EERE)

    Countries Bhutan, China, Nepal, Mongolia, India, North Korea, South Korea, Vietnam, Laos, Thailand, Cambodia, Philippines, Bangladesh UN Region Southern Asia, Eastern Asia,...

  1. Nonproliferation | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    dispose of dangerous nuclear and radiological material, and detect and control the proliferation of related WMD technology and expertise. Vietnam Removal Working in close...

  2. BACKGROUND GLOBAL STEEL OVERCAPACITY and OIL COUNTRY TUBULAR...

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

    Oil Country Tubular Goods (OCTG) producers filed anti- dumping cases against South Korea, India, the Philippines, Saudi Arabia, Taiwan, Thailand, Turkey, Ukraine and Vietnam. ...

  3. Development of Sea Level Rise Scenarios for Climate Change Assessments...

    Open Energy Info (EERE)

    Sea Level Rise Scenarios for Climate Change Assessments of the Mekong Delta, Vietnam Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Development of Sea Level Rise...

  4. 27264_ESNet_HEP_NP_Cover_final3_102113

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

    ... With ESnet's knowledge and experience, these local partnerships made possible the Eastern ... Russia, Saudi Arabia, Slovenia, Spain, Taiwan, Thailand, Turkey, Ukraine, and Vietnam. ...

  5. Chile-Danish Government Baseline Workstream | Open Energy Information

    Open Energy Info (EERE)

    Kenya, Mexico, South Africa, Thailand and Vietnam), to share practices on setting national greenhouse gas emissions baseline scenarios. The aim of the workstream is to...

  6. Viet Nam Rural Electrification | Open Energy Information

    Open Energy Info (EERE)

    Rural Electrification Location of project Vietnam Energy Services Lighting, Cooking and water heating, Space heating, Cooling Year initiated 2009 Organization Asian Development...

  7. UNEP-Risoe-Economics of GHG Limitations: Country Study Series...

    Open Energy Info (EERE)

    Econo References Economics of Greenhouse Gas Limitations1 Country study series: Argentina, Ecuador, Estonia, Hungary, Indonesia, Mauritius, Senegal, Vietnam Parallel country...

  8. Argonne National Laboratory Develops Extreme-Scale Wind Farm...

    Broader source: Energy.gov (indexed) [DOE]

    A wake of a wind turbine modeled by the actuator line model in Nek5000 A wake of a wind turbine modeled by the actuator line model in Nek5000 This is an excerpt from the Third ...

  9. A Minnesota Blizzard Provides Insight into Utility-Scale Wind...

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

    A Minnesota Blizzard Provides Insight into Utility-Scale Wind Turbine Wakes A Minnesota Blizzard Provides Insight into Utility-Scale Wind Turbine Wakes September 12, 2014 - 11:22am ...

  10. Plasma Wakefield Acceleration: How it Works

    SciTech Connect (OSTI)

    2014-11-05

    This animation explains how electrons can be efficiently accelerated to high energy using wakes created in a plasma.

  11. Design, Integration, Communication and Construction Engineering 2

    National Nuclear Security Administration (NNSA)

    1, 2016 QUESTIONS SUBMITTED BY DICCE2 INDUSTRY DAY ATTENDEES on 9/23/15 1. The sample task is Vietnam. Is either of the incumbent contractor's currently working there? Conflict? a. The Vietnam project is not a sample task, it is a real project that will be awarded as a Task Order. Neither incumbents are currently working in Vietnam under any NSDD contract. 2. If required to go to a High Risk site, will security and life support be a contractor responsibility? a. Each contractor makes a safety

  12. Design, Integration, Communication and Construction Engineering 2

    National Nuclear Security Administration (NNSA)

    8, 2016 QUESTIONS SUBMITTED AFTER DICCE2 REQUEST FOR PROPOSAL RELEASE DATE OF 2/1/2016 1. Section L Attachment L-7a Vietnam Statement of Work. Does each lane already have adequate electric to power proposed RPM equipment? If not which building should power be routed from? a. Response: This information is contained in the Vietnam Design Requirements Document, specifically section 3.1.4. 2. Section L Attachment L-7a Vietnam Statement of Work. Does each lane where the RPM units are being installed

  13. armed forces

    National Nuclear Security Administration (NNSA)

    organization that takes World War II, Korean War and Vietnam War veterans to the U.S. capital to see the memorials built in their honor at zero cost to the veteran.

  14. veterans

    National Nuclear Security Administration (NNSA)

    organization that takes World War II, Korean War and Vietnam War veterans to the U.S. capital to see the memorials built in their honor at zero cost to the veteran.

  15. TTW 11-9-06

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

    ... Dennis Hurtt U.S. Army 1964-1967 I wish all veterans a safe Veterans' Day on November 11 and ask everyone to remember Korea, Vietnam, Afghanistan and Iraq veterans and the ...

  16. [pic] EERE Web Site Statistics - Lose Your Excuse

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

    ... Federation|52|0%| |25.|Spain|52|0%| |26.|Indonesia|52|0%| |27.|Thailand|52|0%| |28.|Vietnam|51|0%| |29.|Belgium|48|0%| |30.|France|47|0%| |31.|Philippines|46|0%| ...

  17. Patricia Hagerty, Aviation Program Analyst

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

    United States. Pat has two bachelor's degrees from the University of Montana; she is a certified general aviation private pilot and a Vietnam Era Veteran of the U.S. Coast Guard.

  18. Y-12s Training and Technology ? TAT and John Ray

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

    AFB in North Carolina. He completed a tour of Vietnam during the war and a tour of Turkey, earning a bronze medal and the distinguished flying cross. During both tours we lived...

  19. TASK ORDER

    National Nuclear Security Administration (NNSA)

    NA0000XXX Task Order No: DE-DT000XXXX Statement of Work August 7, 2015 Task Order Title: Design, Integration, Construction, Communications, and Engineering (DICCE) Services for Port of Cat Lai, Vietnam. Scope: The Contractor shall design, construct, and integrate fully functional portal monitor and communications systems at designated sites in Vietnam. * Port of Cat Lai Requirements Documents: The following task order requirements describe key milestones and deliverables. For a more complete

  20. NNSA Completes Fourth International Meeting on Next Generation Nuclear

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

    Safeguards | National Nuclear Security Administration | (NNSA) NNSA Completes Fourth International Meeting on Next Generation Nuclear Safeguards July 12, 2012 HANOI, VIETNAM - The U.S. Department of Energy's National Nuclear Security Administration (NNSA), together with the Vietnam Agency for Radiation and Nuclear Safety, announced today the successful completion of the Fourth International Meeting on Next Generation Safeguards. Organized by NNSA's Next Generation Safeguards Initiative

  1. NREL: Technology Deployment - Developing Countries Demonstrate Impacts of

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

    Low Emission Development Strategies Developing Countries Demonstrate Impacts of Low Emission Development Strategies News EC-LEDS Highlights Renewable Energy Resource Data at COP21 Vietnam Makes Strides to Lower Emissions Thru Green Building Code, High-Performance Buildings Colombia Makes Major Strides in Low Emission Development Payments for Forest Environmental Services in Vietnam Preserves Forests, Engages Communities Presidential Engagement on Low Emission Development Strategies in Gabon

  2. Attachment L-7a U.S. DEPARTMENT OF ENERGY NATIONAL NUCLEAR SECURITY ADMINISTRATION

    National Nuclear Security Administration (NNSA)

    AM52-08NAXXXXX Task Order No: DT000XXXX Statement of Work August 7, 2015 Task Order Title: Design, Integration, Construction, Communications, and Engineering (DICCE) Services for Port of Cat Lai, Vietnam. Scope: The Contractor shall design, construct, and integrate fully functional portal monitor and communications systems at designated sites in Vietnam.  Port of Cat Lai Requirements Documents: The following task order requirements describe key milestones and deliverables. For a more complete

  3. Attachment L-7c

    National Nuclear Security Administration (NNSA)

    c [Type here] VIETNAM MOBILIZATION PLAN DE-SOL-0008449 1.0 INTRODUCTION Based on the information presented below, the Statement of Work requirements relating to in- country deployments, and the Work Breakdown Structure (WBS) provided in Table 1, the Offeror shall develop a mobilization plan that describes its approach to a comprehensive Nuclear Smuggling Detection and Deterrence (NSDD) deployment involving Port of Cat Lai seaport in Vietnam. 2.0 REQUIREMENTS The Offeror shall provide a plan for

  4. DE-SOL-0008449 Attachment L-7c

    National Nuclear Security Administration (NNSA)

    DE-SOL-0008449 Attachment L-7c [Type here] VIETNAM MOBILIZATION PLAN DE-SOL-0008449 1.0 INTRODUCTION Based on the information presented below, the Statement of Work requirements relating to in- country deployments, and the Work Breakdown Structure (WBS) provided in Table 1, the Offeror shall develop a mobilization plan that describes its approach to a comprehensive Nuclear Smuggling Detection and Deterrence (NSDD) deployment involving Port of Cat Lai seaport in Vietnam. 2.0 REQUIREMENTS The

  5. Improved input and output couplers for SC acceleration structure

    SciTech Connect (OSTI)

    Solyak, N.; Gonin, I.; Latina, A.; Lunin, A.; Poloubotko, V.; Yakovlev, V.; /Fermilab

    2009-04-01

    Different couplers are described that allow the reduction of both transverse wake potential and RF kick in the SC acceleration structure of ILC. A simple rotation of the couplers reducing the RF kick and transverse wake kick is discussed for both the main linac and bunch compressors, along with possible limitations of this method. Designs of a coupler unit are presented which preserve axial symmetry of the structure, and provide reduced both the RF kick and transverse wake field.

  6. Sandia Energy Technical Highlights

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

    +0000 http:energy.sandia.gov?p34801 http:energy.sandia.govsandia-wake-imaging-system-successfully-deployed-at-scaled-wind-farm-technology-facilityfeed 0 Sandia...

  7. Bowie County, Texas: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Texas De Kalb, Texas Hooks, Texas Leary, Texas Maud, Texas Nash, Texas New Boston, Texas Red Lick, Texas Redwater, Texas Texarkana, Texas Wake Village, Texas Retrieved from "http:...

  8. SWiFT Facility Prepared for More-Efficient Operations & Advanced...

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

    Prepared for More-Efficient Operations & Advanced Turbine-Turbine Wake-Interaction-Control Research - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee ...

  9. Sandia Is Developing a Doppler Global Velocimetry System to Understand...

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

    Is Developing a Doppler Global Velocimetry System to Understand Fundamental Wind-Turbine ... System to Understand Fundamental Wind-Turbine Wake Phenomena HomeComputational ...

  10. Microsoft Word - 2014 Scaled Wind Farm Technology Facility Overview...

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

    ... shapes and frequencies exactly during the reduction process. ... wake with a strong tip vortex, to a disorganized highly ... Using the above described tools, new technologies can be ...

  11. EC Publications

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

    Modeling and Analysis, Renewable Energy, Water Power, Wind Energy slidetemplate default CACTUS simulation of the wake of a three-bladed Darrieus vertical-axis wind turbine

  12. Sandia National Laboratories: Lessons from Fukushima

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

    Sandia helps spread lessons learned from Japanese reactor accident The Fukushima reactor complex in Japan suffered catastrophic failure in 2011 in the wake of an earthquake and ...

  13. Wind Energy

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

    Wind Energy The DTU SpinnerLidar installed in the nacelle of the SWiFT facility A1 turbine Permalink Gallery First Wake Data Captured During Wake Steering Experiment at the SWiFT Facility News, Renewable Energy, SWIFT, Wind Energy, Wind News First Wake Data Captured During Wake Steering Experiment at the SWiFT Facility Researchers at Sandia National Laboratories and the National Renewable Energy Laboratory (NREL) have met a major project milestone as part of the Department of Energy Atmosphere

  14. Modeling

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

    & Capabilities, SWIFT, Systems Analysis, Technical Highlights, Wind Energy, Wind News Sandia Wake-Imaging System Successfully Deployed at Scaled Wind Farm Technology Facility The ...

  15. Sandia National Laboratories Hits Milestone, Gears Up for 2016...

    Office of Environmental Management (EM)

    ... To support A2e's industrial partnership objectives, SWiFT will partner with Windar Photonics and Westergaard Solutions to investigate simultaneous feedforwardfeedbackward wake ...

  16. President Obama Visits DOE to Discuss Preparations for Hurricane...

    Office of Environmental Management (EM)

    The President discussed that in the wake of major disasters like Hurricane Sandy extended power outages can have major impacts on communities and recovery efforts, and that beyond ...

  17. Precise Calculation of Traveling-Wave Periodic Structure

    SciTech Connect (OSTI)

    Wang, L.; Li, Z.; Seryi, A.; /SLAC

    2007-07-06

    The effects of the round edge beam hole on the frequency and wake field are studied using variational method, which allows for rounded iris disk hole without any approximation in shape treatment. The frequency and wake field of accelerating mode and dipole mode are studied for different edge radius cases, including the flat edge shape that is often used to approximately represent the actual structure geometry. The edge hole shape has weak effect on the frequency, but much effect on the wake field. Our study shows that the amounts of wake fields are not precise enough with the assumption of the flat edge beam hole instead of round edge.

  18. Fermilab | Newsroom | Press Releases

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

    National laboratories offer computing time to Japanese physicists in wake of earthquake Fermilab theoretical physicist Paul Mackenzie, spokesperson for the USQCD...

  19. Press Pass - Press Releases

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

    2311 National laboratories offer computing time to Japanese physicists in wake of earthquake 032311 Fermilab hosts STEM Career Expo for high school students April 13: A chance...

  20. Karen Patterson | Department of Energy

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

    Ms. Patterson received her Bachelor's degree in Biology from Randolph-Macon Women's College, a Masters in Biology from Wake Forest University and a Master's of Library and ...

  1. Saluting Daniel Poneman's Service to the Department of Energy...

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

    ... and response capabilities, leading the Department's efforts in the wake of the Fukushima Daiichi disaster in 2011, as well as during and after Hurricane Sandy in 2012. In ...

  2. Slide 1

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

    ... Understanding laser evolution (effect of laser mode and background plasma density on laser propagation): limit cap damage & provide "best" wake for acceleration features of ...

  3. Numerical investigation of electron self-injection in the nonlinear bubble regime

    SciTech Connect (OSTI)

    Benedetti, C.; Schroeder, C. B.; Esarey, E.; Leemans, W. P.; Rossi, F.

    2013-10-15

    The process of electron self-injection in the nonlinear bubble wake generated by a short and intense laser pulse propagating in a uniform underdense plasma is studied by means of fully self-consistent particle-in-cell simulations and test-particle simulations. We consider a wake generated by a non-evolving laser driver traveling with a prescribed velocity, which then sets the structure and the velocity of the wake, so the injection dynamics is decoupled from driver evolution, but a realistic structure for the wakefield is retained. We show that a threshold for self-injection into a non-evolving bubble wake exists, and we characterize the dependence of the self-injection threshold on laser intensity, wake velocity, and plasma temperature for a range of parameters of interest for current and future laser-plasma accelerators.

  4. Analyzing Effects of Turbulence on Power Generation Using Wind Plant Monitoring Data: Preprint

    SciTech Connect (OSTI)

    Zhang, J.; Chowdhury, S.; Hodge, B. M.

    2014-01-01

    In this paper, a methodology is developed to analyze how ambient and wake turbulence affects the power generation of a single wind turbine within an array of turbines. Using monitoring data from a wind power plant, we selected two sets of wind and power data for turbines on the edge of the wind plant that resemble (i) an out-of-wake scenario (i.e., when the turbine directly faces incoming winds) and (ii) an in-wake scenario (i.e., when the turbine is under the wake of other turbines). For each set of data, two surrogate models were then developed to represent the turbine power generation (i) as a function of the wind speed; and (ii) as a function of the wind speed and turbulence intensity. Support vector regression was adopted for the development of the surrogate models. Three types of uncertainties in the turbine power generation were also investigated: (i) the uncertainty in power generation with respect to the published/reported power curve, (ii) the uncertainty in power generation with respect to the estimated power response that accounts for only mean wind speed; and (iii) the uncertainty in power generation with respect to the estimated power response that accounts for both mean wind speed and turbulence intensity. Results show that (i) under the same wind conditions, the turbine generates different power between the in-wake and out-of-wake scenarios, (ii) a turbine generally produces more power under the in-wake scenario than under the out-of-wake scenario, (iii) the power generation is sensitive to turbulence intensity even when the wind speed is greater than the turbine rated speed, and (iv) there is relatively more uncertainty in the power generation under the in-wake scenario than under the out-of-wake scenario.

  5. SOPAC marine geology atlases

    SciTech Connect (OSTI)

    Chase, T.E.; Seekins, B.A.; Young, J.D.; Wahler, J.A.

    1986-07-01

    The US Geological Survey conducted a series of marine geologic and geophysical cruises in the southwest Pacific Ocean in 1982 and 1984 as part of a program with participation by Australia and New Zealand. These two SOPAC expeditions obtained various data, which have been compiled into a series of charts and thematic products for the offshore areas of Tonga, Fiji, Vanuatu, the Solomon Islands, and Papua New Guinea. The maps and charts presently being compiled or revised combine previously collected data with information from the SOPAC expeditions. Regional charts at a scale of approximately 1:3 million are included, and more detailed coverage is available at 1:1 million. Additional geologic information-such as gravity, magnetics, and possibly sediment isopachs-is provided on overlays to the topographic base charts. Reproductions of the seismic reflection data are also included, and tracklines with both time marks and shotpoints will permit correlation with the analog and digital seismic records.

  6. Capturing relativistic wakefield structures in plasmas using ultrashort high-energy electrons as a probe

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

    Zhang, C. J.; Hua, J. F.; Xu, X. L.; Li, F.; Pai, C. -H.; Wan, Y.; Wu, Y. P.; Gu, Y. Q.; Mori, W. B.; Joshi, C.; et al

    2016-07-11

    A new method capable of capturing coherent electric field structures propagating at nearly the speed of light in plasma with a time resolution as small as a few femtoseconds is proposed. This method uses a few femtoseconds long relativistic electron bunch to probe the wake produced in a plasma by an intense laser pulse or an ultra-short relativistic charged particle beam. As the probe bunch traverses the wake, its momentum is modulated by the electric field of the wake, leading to a density variation of the probe after free-space propagation. This variation of probe density produces a snapshot of themore » wake that can directly give many useful information of the wake structure and its evolution. Furthermore, this snapshot allows detailed mapping of the longitudinal and transverse components of the wakefield. We develop a theoretical model for field reconstruction and verify it using 3-dimensional particle-in-cell (PIC) simulations. This model can accurately reconstruct the wakefield structure in the linear regime, and it can also qualitatively map the major features of nonlinear wakes. As a result, the capturing of the injection in a nonlinear wake is demonstrated through 3D PIC simulations as an example of the application of this new method.« less

  7. A Look Inside the Detroit Auto Show | Department of Energy

    Energy Savers [EERE]

    the Detroit Auto Show A Look Inside the Detroit Auto Show January 12, 2011 - 1:15pm Addthis Kerry Duggan Kerry Duggan Waking up at 4:30AM is not my idea of fun. But after I ...

  8. DOE's NREL and LLNL team with NOAA and University of Colorado...

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

    can be critical to advancing turbine design and improving their siting within wind farms. ... To gain new insights into turbine wind wakes, the U.S. Department of Energy's Wind Program ...

  9. Microsoft Word - OUTLOOK_SNV_Dec09 edit dec 13 by mary.docx

    National Nuclear Security Administration (NNSA)

    ... However, oil-price shocks, first during the Arab oil embargo of 1973 and a subsequent decline in imports from the Middle East following the wake of the Iranian revolution in 1979, ...

  10. CSR in the SuperKEKB Damping Ring (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    From the impedances due to CSR, resistive wall and various vacuum components, quasi-Green function wake potentials were constructed and used in simulations of Particle-In-Cell (PIC...

  11. Green Functions for the Radial Electric Component of the Monopole...

    Office of Scientific and Technical Information (OSTI)

    Green Functions for the Radial Electric Component of the Monopole Wake Field in a Round Resistive Chamber Citation Details In-Document Search Title: Green Functions for the Radial...

  12. Sandia Energy - Computational Fluid Dynamics Simulations Provide...

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

    from a VWiS large-eddy simulation. One of the primary roles of Sandia's Scaled Wind Farm Technology (SWiFT) facility will be to conduct detailed experiments on turbine wakes and...

  13. NREL Studies Wind Farm Aerodynamics to Improve Siting (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-04-01

    NREL researchers have used high-tech instruments and high-performance computing to understand atmospheric turbulence and turbine wake behavior in order to improve wind turbine design and siting within wind farms.

  14. EC Publications

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

    Water Power author B. Gunawan, V. Neary, C. Hill, L. Chamarro year 2012 Wake recovery constrains the downstream spacing and density of turbines that can be deployed in turbine ...

  15. CREATING THE NORTHEAST GASOLINE SUPPLY RESERVE | Department of...

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

    diesel, which was used for the first time by first-responders and to fill emergency generators in the wake of Superstorm Sandy. Beyond the Northeast, the Energy Department is not...

  16. OSTI, US Dept of Energy, Office of Scientific and Technical Informatio...

    Office of Scientific and Technical Information (OSTI)

    NREL Topic Wind Power Research Excitement by Kathy Chambers 06 Aug, 2012 in Science Communications 3D model of wind plant aerodynamics that shows low velocity wakes and the result ...

  17. OSTI, US Dept of Energy, Office of Scientific and Technical Informatio...

    Office of Scientific and Technical Information (OSTI)

    Wind Power Topic Wind Power Research Excitement by Kathy Chambers 06 Aug, 2012 in Science Communications 3D model of wind plant aerodynamics that shows low velocity wakes and the ...

  18. Transverse Mode Coupling Instability with chromaticity and space charge

    SciTech Connect (OSTI)

    Balbekov, V.

    2014-10-29

    Transverse mode coupling instability is considered in the paper at different bunch and wake shapes. Exact solution for “hollow” bunch is arrived at and used to develop a proper technique for more realistic distributions. The three-modes approach is proposed for arbitrary bunch with chromaticity included. It is shown that the TMCI threshold and rate depend only slightly on the bunch model used being rather sensitive to the wake shape. Resistive wall wake is considered in detail, and a comparison of the TMCI and collective mode instability with this wake is performed. Space charge tune shift of arbitrary value is included in the consideration providing a firm bridge between the known cases of absent and dominating space charge

  19. ARM - Feature Stories and Releases Article

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

    to help them understand why the rain in the Great Plains falls mainly in the dark. Their marathon of wakefulness is called PECAN, the Plains Elevated Convection at Night field...

  20. Sandia Energy Sensing & Monitoring

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

    SWiFT Facility Prepared for More-Efficient Operations & Advanced Turbine-Turbine Wake-Interaction-Control Research http:energy.sandia.govswift-facility-prepared-for-more-efficie...

  1. Sandia Energy Sensing

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

    SWiFT Facility Prepared for More-Efficient Operations & Advanced Turbine-Turbine Wake-Interaction-Control Research http:energy.sandia.govswift-facility-prepared-for-more-efficie...

  2. Happy Thanksgiving

    Broader source: Energy.gov [DOE]

    Here at the Energy Blog, we're anticipating stuffing our faces with tasty food, succumbing to the unavoidable post-meal slumber and waking up the next day to munch on leftovers.

  3. Spectral diagnostics of laser wakefield in capillary tubes

    SciTech Connect (OSTI)

    Andreev, N.E.; Chegotov, M.V.; Cros, B.; Mora, P.; Vieux, G.

    2006-05-15

    The modification of the spectrum of a probe pulse traveling in a linear plasma wave created in the wake of a pump pulse guided inside a capillary tube is analyzed for the cases of narrow or broad chirped probe spectra. It is shown that in both cases the measurement of the spectrum can be used as a diagnostic for the amplitude of the plasma wave. The results of full-scale numerical modeling confirm the developed analytical theory of wake-field diagnostics.

  4. Women @ Energy: Julie Ezold

    Broader source: Energy.gov [DOE]

    "I always tell high schoolers and college students to find something that excites you; for you will spend more of your waking hours at your job then you will outside of it. It should be everyone’s goal to find a career such that when you wake up and the morning you are looking forward to going into to work." Read more from Julie on her profile here.

  5. SWiFT Facility Prepared for More-Efficient Operations & Advanced

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

    Turbine-Turbine Wake-Interaction-Control Research Prepared for More-Efficient Operations & Advanced Turbine-Turbine Wake-Interaction-Control Research - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy

  6. Sandia Is Developing a Doppler Global Velocimetry System to Understand

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

    Fundamental Wind-Turbine Wake Phenomena Is Developing a Doppler Global Velocimetry System to Understand Fundamental Wind-Turbine Wake Phenomena - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage

  7. NREL Studies Wind Farm Aerodynamics to Improve Siting (Fact Sheet), Innovation Impact: Wind, NREL (National Renewable Energy Laboratory)

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

    Studies Wind Farm Aerodynamics to Improve Siting NREL researchers are using advanced remote sensing instruments and high- performance computing to understand atmospheric turbulence and turbine wake behavior-a key to improving wind turbine design and siting within wind farms. As turbines and wind farms grow in size, they create bigger wakes and present more complex challenges to wind turbine and wind farm designers and operators. NREL researchers have confirmed through both observation and

  8. Bow Wave from Ultraintense Electromagnetic Pulses in Plasmas

    SciTech Connect (OSTI)

    Esirkepov, T. Zh.; Bulanov, S. V.; Kato, Y.

    2008-12-31

    We show a new effect of the bow-wave excitation by an intense short laser pulse propagating in underdense plasma. Because of spreading of the laser pulse energy in transverse direction, the bow wave causes a large-scale transverse modulation of the electron density. This can significantly increase the electric potential of the wake wave since the wake wave is generated in the region much wider than the laser pulse waist.

  9. Investigations of the plasma and structure based accelerators

    SciTech Connect (OSTI)

    Shvets, Gennady

    2012-08-30

    The objective of our research during the reported period was three-fold: (a) theoretical investigation of novel mechanisms of injection into laser wake field accelerators; (b) theoretical investigation of single-shot frequency domain diagnostics of relativistic plasma wakes, specifically in the context of spatio-temporal evolution of the plasma bubble;(c) experimental and theoretical investigation of laser-driven accelerating structure, specifically in the context of the Surface Wave Accelerator Based on SiC (SWABSIC).

  10. Single bunch transverse instability in a circular accelerator with chromaticity and space charge

    SciTech Connect (OSTI)

    Balbekov, V.

    2015-10-21

    The transverse instability of a bunch in a circular accelerator is elaborated in this paper. A new tree-modes model is proposed and developed to describe the most unstable modes of the bunch. This simple and flexible model includes chromaticity and space charge, and can be used with any bunch and wake forms. The dispersion equation for the bunch eigentunes is obtained in form of a third-order algebraic equation. The known head-tail and TMCI modes appear as the limiting cases which are distinctly bounded at zero chromaticity only. It is shown that the instability parameters depend only slightly on the bunch model but they are rather sensitive to the wake shape. In particular, space charge effects are investigated in the paper and it is shown that their influence depends on sign of wake field enhancing the bunch stability if the wake is negative. In addition, the resistive wall wake is considered in detail including a comparison of single and collective effects. A comparison of the results with earlier publications is carried out.