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Effect of Second-Order Hydrodynamics on Floating Offshore Wind Turbines: Preprint (open access)

Effect of Second-Order Hydrodynamics on Floating Offshore Wind Turbines: Preprint

Offshore winds are generally stronger and more consistent than winds on land, making the offshore environment attractive for wind energy development. A large part of the offshore wind resource is however located in deep water, where floating turbines are the only economical way of harvesting the energy. The design of offshore floating wind turbines relies on the use of modeling tools that can simulate the entire coupled system behavior. At present, most of these tools include only first-order hydrodynamic theory. However, observations of supposed second-order hydrodynamic responses in wave-tank tests performed by the DeepCwind consortium suggest that second-order effects might be critical. In this paper, the methodology used by the oil and gas industry has been modified to apply to the analysis of floating wind turbines, and is used to assess the effect of second-order hydrodynamics on floating offshore wind turbines. The method relies on combined use of the frequency-domain tool WAMIT and the time-domain tool FAST. The proposed assessment method has been applied to two different floating wind concepts, a spar and a tension-leg-platform (TLP), both supporting the NREL 5-MW baseline wind turbine. Results showing the hydrodynamic forces and motion response for these systems are presented and analysed, and …
Date: July 1, 2013
Creator: Roald, L.; Jonkman, J.; Robertson, A, & Chokani, N.
Object Type: Article
System: The UNT Digital Library
GMTI processing using back projection. (open access)

GMTI processing using back projection.

Backprojection has long been applied to SAR image formation. It has equal utility in forming the range-velocity maps for Ground Moving Target Indicator (GMTI) radar processing. In particular, it overcomes the problem of targets migrating through range resolution cells.
Date: July 1, 2013
Creator: Doerry, Armin Walter
Object Type: Report
System: The UNT Digital Library
ASME Material Challenges for Advanced Reactor Concepts (open access)

ASME Material Challenges for Advanced Reactor Concepts

This study presents the material Challenges associated with Advanced Reactor Concept (ARC) such as the Advanced High Temperature Reactor (AHTR). ACR are the next generation concepts focusing on power production and providing thermal energy for industrial applications. The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The heat exchanger required for AHTR is subjected to a unique set of conditions that bring with them several design challenges not encountered in standard heat exchangers. The corrosive molten salts, especially at higher temperatures, require materials throughout the system to avoid corrosion, and adverse high-temperature effects such as creep. Given the very high steam generator pressure of the supercritical steam cycle, it is anticipated that water tube and molten salt shell steam generators heat exchanger will be used. In this paper, the ASME Section III and the American Society of Mechanical Engineers (ASME) Section VIII requirements (acceptance criteria) are discussed. Also, the ASME material acceptance criteria (ASME Section II, Part D) for high temperature environment are presented. Finally, lack of ASME acceptance criteria for thermal design and analysis are discussed.
Date: July 1, 2013
Creator: Sabharwall, Piyush & Siahpush, Ali
Object Type: Article
System: The UNT Digital Library

Reliability of Bonded Interfaces

Presentation details the thermal performance and the reliability of electrical interconnects.
Date: July 1, 2013
Creator: DeVoto, D.
Object Type: Presentation
System: The UNT Digital Library
Electric Ground Support Equipment Advanced Battery Technology Demonstration Project at the Ontario Airport (open access)

Electric Ground Support Equipment Advanced Battery Technology Demonstration Project at the Ontario Airport

The intent of the electric Ground Support Equipment (eGSE) demonstration is to evaluate the day-to-day vehicle performance of electric baggage tractors using two advanced battery technologies to demonstrate possible replacements for the flooded lead-acid (FLA) batteries utilized throughout the industry. These advanced battery technologies have the potential to resolve barriers to the widespread adoption of eGSE deployment. Validation testing had not previously been performed within fleet operations to determine if the performance of current advanced batteries is sufficient to withstand the duty cycle of electric baggage tractors. This report summarizes the work performed and data accumulated during this demonstration in an effort to validate the capabilities of advanced battery technologies. This report summarizes the work performed and data accumulated during this demonstration in an effort to validate the capabilities of advanced battery technologies. The demonstration project also grew the relationship with Southwest Airlines (SWA), our demonstration partner at Ontario International Airport (ONT), located in Ontario, California. The results of this study have encouraged a proposal for a future demonstration project with SWA.
Date: July 1, 2013
Creator: Gray, Tyler; Diez, Jeremy; Wishart, Jeffrey & Francfort, James
Object Type: Report
System: The UNT Digital Library
Path Integral for Stochastic Inflation: Non-Perturbative Volume Weighting, Complex Histories, Initial Conditions and the End of Inflation (open access)

Path Integral for Stochastic Inflation: Non-Perturbative Volume Weighting, Complex Histories, Initial Conditions and the End of Inflation

None
Date: July 1, 2013
Creator: Gratton, Steven & /KIPAC, Menlo Park /Cambridge U.
Object Type: Article
System: The UNT Digital Library
Fuel Synthesis Catalysis Laboratory (Fact Sheet) (open access)

Fuel Synthesis Catalysis Laboratory (Fact Sheet)

This fact sheet provides information about Fuel Synthesis Catalysis Laboratory capabilities and applications at NREL's National Bioenergy Center.
Date: July 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
New Automotive Air Conditioning System Simulation Tool Developed in MATLAB/Simulink (open access)

New Automotive Air Conditioning System Simulation Tool Developed in MATLAB/Simulink

Further improvements in vehicle fuel efficiency require accurate evaluation of the vehicle's transient total power requirement. When operated, the air conditioning (A/C) system is the largest auxiliary load on a vehicle; therefore, accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation software, such as 'Autonomie,' has been used by OEMs to evaluate vehicles' energy performance. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software Matlab/Simulink was used to develop new and more efficient vehicle energy system controls. The various modeling methods used for the new simulation tool are described in detail. Comparison with measured data is provided to demonstrate the validity of the model.
Date: July 1, 2013
Creator: Kiss, T.; Chaney, L. & Meyer, J.
Object Type: Article
System: The UNT Digital Library
Spatially varying embedded stochastic galerkin methods for steady-state PDEs. (open access)

Spatially varying embedded stochastic galerkin methods for steady-state PDEs.

Existing discretizations for stochastic PDEs, based on a tensor product between the deterministic basis and the stochastic basis, treat the required resolution of uncertainty as uniform across the physical domain. However, solutions to many PDEs of interest exhibit spatially localized features that may result in uncertainty being severely over or under-resolved by existing discretizations. In this report, we explore the mechanics and accuracy of using a spatially varying stochastic expansion. This is achieved through an adaptive refinement algorithm where simple error estimates are used to independently drive refinement of the stochastic basis at each point in the physical domain. Results are presented comparing the accuracy of the adaptive techinque to the accuracy achieved using uniform refinement.
Date: July 1, 2013
Creator: Cyr, Eric Christopher
Object Type: Report
System: The UNT Digital Library
GOMA 6.0 : a full-Newton finite element program for free and moving boundary problems with coupled fluid/solid momentum, energy, mass, and chemical species transport : user%3CU%2B2019%3Es guide. (open access)

GOMA 6.0 : a full-Newton finite element program for free and moving boundary problems with coupled fluid/solid momentum, energy, mass, and chemical species transport : user%3CU%2B2019%3Es guide.

Goma 6.0 is a finite element program which excels in analyses of multiphysical processes, particularly those involving the major branches of mechanics (viz. fluid/solid mechanics, energy transport and chemical species transport). Goma is based on a full-Newton-coupled algorithm which allows for simultaneous solution of the governing principles, making the code ideally suited for problems involving closely coupled bulk mechanics and interfacial phenomena. Example applications include, but are not limited to, coating and polymer processing flows, super-alloy processing, welding/soldering, electrochemical processes, and solid-network or solution film drying. This document serves as a user's guide and reference.
Date: July 1, 2013
Creator: Schunk, Peter Randall; Rao, Rekha Ranjana; Chen, Ken Shuang; Labreche, Duane A.; Sun, Amy Cha-Tien; Hopkins, Matthew Morgan et al.
Object Type: Report
System: The UNT Digital Library
Continuously Optimized Reliable Energy (CORE) Microgrid: Models & Tools (Fact Sheet) (open access)

Continuously Optimized Reliable Energy (CORE) Microgrid: Models & Tools (Fact Sheet)

This brochure describes Continuously Optimized Reliable Energy (CORE), a trademarked process NREL employs to produce conceptual microgrid designs. This systems-based process enables designs to be optimized for economic value, energy surety, and sustainability. Capabilities NREL offers in support of microgrid design are explained.
Date: July 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Innovation Impact: Breakthrough Research Results (open access)

Innovation Impact: Breakthrough Research Results

The Innovation Impact brochure captures key breakthrough results across NREL's primary areas of renewable energy and energy efficiency research: solar, wind, bioenergy, transportation, buildings, analysis, and manufacturing technologies.
Date: July 1, 2013
Creator: unknown
Object Type: Pamphlet
System: The UNT Digital Library
Reducing uncertainty in high-resolution sea ice models. (open access)

Reducing uncertainty in high-resolution sea ice models.

Arctic sea ice is an important component of the global climate system, reflecting a significant amount of solar radiation, insulating the ocean from the atmosphere and influencing ocean circulation by modifying the salinity of the upper ocean. The thickness and extent of Arctic sea ice have shown a significant decline in recent decades with implications for global climate as well as regional geopolitics. Increasing interest in exploration as well as climate feedback effects make predictive mathematical modeling of sea ice a task of tremendous practical import. Satellite data obtained over the last few decades have provided a wealth of information on sea ice motion and deformation. The data clearly show that ice deformation is focused along narrow linear features and this type of deformation is not well-represented in existing models. To improve sea ice dynamics we have incorporated an anisotropic rheology into the Los Alamos National Laboratory global sea ice model, CICE. Sensitivity analyses were performed using the Design Analysis Kit for Optimization and Terascale Applications (DAKOTA) to determine the impact of material parameters on sea ice response functions. Two material strength parameters that exhibited the most significant impact on responses were further analyzed to evaluate their influence on quantitative …
Date: July 1, 2013
Creator: Peterson, Kara J. & Bochev, Pavel Blagoveston
Object Type: Report
System: The UNT Digital Library

Integrated Vehicle Thermal Management - Combining Fluid Loops in Electric Drive Vehicles

Plug-in hybrid electric vehicles and electric vehicles have increased vehicle thermal management complexity, using separate coolant loop for advanced power electronics and electric motors. Additional thermal components result in higher costs. Multiple cooling loops lead to reduced range due to increased weight. Energy is required to meet thermal requirements. This presentation for the 2013 Annual Merit Review discusses integrated vehicle thermal management by combining fluid loops in electric drive vehicles.
Date: July 1, 2013
Creator: Rugh, J. P.
Object Type: Presentation
System: The UNT Digital Library
Next Generation Solvent Development for Caustic-Side Solvent Extraction of Cesium (open access)

Next Generation Solvent Development for Caustic-Side Solvent Extraction of Cesium

This report summarizes the FY 2010 and 2011 accomplishments at Oak Ridge National Laboratory (ORNL) in developing the Next Generation Caustic-Side Solvent Extraction (NG-CSSX) process, referred to commonly as the Next Generation Solvent (NGS), under funding from the U.S. Department of Energy, Office of Environmental Management (DOE-EM), Office of Technology Innovation and Development. The primary product of this effort is a process solvent and preliminary flowsheet capable of meeting a target decontamination factor (DF) of 40,000 for worst-case Savannah River Site (SRS) waste with a concentration factor of 15 or higher in the 18-stage equipment configuration of the SRS Modular Caustic-Side Solvent Extraction Unit (MCU). In addition, the NG-CSSX process may be readily adapted for use in the SRS Salt Waste Processing Facility (SWPF) or in supplemental tank-waste treatment at Hanford upon appropriate solvent or flowsheet modifications. Efforts in FY 2010 focused on developing a solvent composition and process flowsheet for MCU implementation. In FY 2011 accomplishments at ORNL involved a wide array of chemical-development activities and testing up through single-stage hydraulic and mass-transfer tests in 5-cm centrifugal contactors. Under subcontract from ORNL, Argonne National Laboratory (ANL) designed a preliminary flowsheet using ORNL cesium distribution data, and Tennessee Technological University …
Date: July 1, 2013
Creator: Duncan, Nathan C; Delmau, Laetitia Helene; Ensor, Dale; Lee, Denise L; Birdwell Jr, Joseph F; Hill, Talon G et al.
Object Type: Report
System: The UNT Digital Library
High temperature storage loop : final design report. (open access)

High temperature storage loop : final design report.

A three year plan for thermal energy storage (TES) research was created at Sandia National Laboratories in the spring of 2012. This plan included a strategic goal of providing test capability for Sandia and for the nation in which to evaluate high temperature storage (>650%C2%B0C) technology. The plan was to scope, design, and build a flow loop that would be compatible with a multitude of high temperature heat transfer/storage fluids. The High Temperature Storage Loop (HTSL) would be reconfigurable so that it was useful for not only storage testing, but also for high temperature receiver testing and high efficiency power cycle testing as well. In that way, HTSL was part of a much larger strategy for Sandia to provide a research and testing platform that would be integral for the evaluation of individual technologies funded under the SunShot program. DOE's SunShot program seeks to reduce the price of solar technologies to 6<U+00A2>/kWhr to be cost competitive with carbon-based fuels. The HTSL project sought to provide evaluation capability for these SunShot supported technologies. This report includes the scoping, design, and budgetary costing aspects of this effort
Date: July 1, 2013
Creator: Gill, David Dennis & Kolb, William J.
Object Type: Report
System: The UNT Digital Library
Status of the Combined Third and Fourth NGNP Fuel Irradiations In the Advanced Test Reactor (open access)

Status of the Combined Third and Fourth NGNP Fuel Irradiations In the Advanced Test Reactor

The United States Department of Energy’s Next Generation Nuclear Plant (NGNP) Advanced Gas Reactor (AGR) Fuel Development and Qualification Program is irradiating up to seven low enriched uranium (LEU) tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States. The experiments will be irradiated over the next several years to demonstrate and qualify new TRISO coated particle fuel for use in high temperature gas reactors. The goals of the experiments are to provide irradiation performance data to support fuel process development, to qualify fuel for normal operating conditions, to support development and validation of fuel performance and fission product transport models and codes, and to provide irradiated fuel and materials for post irradiation examination (PIE) and safety testing. The experiments, which will each consist of several independent capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control of each capsule. The sweep gas will also have on-line fission product monitoring on its effluent to track performance of the fuel in each individual …
Date: July 1, 2013
Creator: Grover, S. Blaine; Petti, David A. & Davenport, Michael E.
Object Type: Article
System: The UNT Digital Library
Demand Response Performance of GE Hybrid Heat Pump Water Heater (open access)

Demand Response Performance of GE Hybrid Heat Pump Water Heater

This report describes a project to evaluate and document the DR performance of HPWH as compared to ERWH for two primary types of DR events: peak curtailments and balancing reserves. The experiments were conducted with GE second-generation “Brillion”-enabled GeoSpring hybrid water heaters in the PNNL Lab Homes, with one GE GeoSpring water heater operating in “Standard” electric resistance mode to represent the baseline and one GE GeoSpring water heater operating in “Heat Pump” mode to provide the comparison to heat pump-only demand response. It is expected that “Hybrid” DR performance, which would engage both the heat pump and electric elements, could be interpolated from these two experimental extremes. Signals were sent simultaneously to the two water heaters in the side-by-side PNNL Lab Homes under highly controlled, simulated occupancy conditions. This report presents the results of the evaluation, which documents the demand-response capability of the GE GeoSpring HPWH for peak load reduction and regulation services. The sections describe the experimental protocol and test apparatus used to collect data, present the baselining procedure, discuss the results of the simulated DR events for the HPWH and ERWH, and synthesize key conclusions based on the collected data.
Date: July 1, 2013
Creator: Widder, Sarah H.; Parker, Graham B.; Petersen, Joseph M. & Baechler, Michael C.
Object Type: Report
System: The UNT Digital Library
Alternative Fuels Data Center (Fact Sheet) (open access)

Alternative Fuels Data Center (Fact Sheet)

Fact sheet describes the Alternative Fuels Data Center, which provides information, data, and tools to help fleets and other transportation decision makers find ways to reduce petroleum consumption through the use of alternative and renewable fuels, advanced vehicles, and other fuel-saving measures.
Date: July 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Using System Dynamics to Define, Study, and Implement Smart Control Strategies on the Electric Power Grid (open access)

Using System Dynamics to Define, Study, and Implement Smart Control Strategies on the Electric Power Grid

The United States electric power grid is the most complex and expansive control system in the world. Local generation control occurs at individual units based on response time and unit economics, larger regional control coordinates unit response to error conditions, and high level large-area regional control is ultimately administered by a network of humans guided by economic and resiliency related factors. Under normal operating conditions, the grid is a relatively slow moving entity that exhibits high inertia to outside stimuli, and behaves along repeatable diurnal and seasonal patterns. However, that paradigm is quickly changing because of the increasing implementation of renewable generation sources. Renewable generators by nature cannot be tightly controlled or scheduled. They appear like a negative load to the system with all of the variability associated with load on a larger scale. Also, grid-reactive loads (i.e. smart devices) can alter their consumption based on price or demand rules adding more variability to system behavior. This paper demonstrates how a systems dynamic modeling approach capable of operating over multiple time scales, can provide valuable insight into developing new “smart-grid” control strategies and devices needed to accommodate renewable generation and regulate the frequency of the grid.
Date: July 1, 2013
Creator: Roybal, Lyle G. & Jeffers, Robert F
Object Type: Article
System: The UNT Digital Library
The INL Nuclear and Radiological Activity Center (open access)

The INL Nuclear and Radiological Activity Center

Since 1949 Idaho National Laboratory (INL) and its
Date: July 1, 2013
Creator: Chichester, D. L.; Sanders, J.; Turnage, J. A. & A., M.
Object Type: Article
System: The UNT Digital Library
Search for CP Violation using T-odd Correlations in D0 \to K+ K-pi+ pi- decays at BaBar (open access)

Search for CP Violation using T-odd Correlations in D0 \to K+ K-pi+ pi- decays at BaBar

None
Date: July 1, 2013
Creator: Martinelli, Maurizio
Object Type: Article
System: The UNT Digital Library
Novel Combination of Enzyme Systems Could Lower Biofuel Costs (Fact Sheet) (open access)

Novel Combination of Enzyme Systems Could Lower Biofuel Costs (Fact Sheet)

Two biomass-degrading enzyme systems that work in very different ways are shown to be more effective at releasing plant sugars when used together.
Date: July 1, 2013
Creator: unknown
Object Type: Report
System: The UNT Digital Library
HOM Damping Coupler Design for the 400-MHz RF Dipole Compact Crab Cavity for the LHC HiLumi Upgrade (open access)

HOM Damping Coupler Design for the 400-MHz RF Dipole Compact Crab Cavity for the LHC HiLumi Upgrade

None
Date: July 1, 2013
Creator: Li, Zenghai; Ge, Lixin; Delayen, J. R. & Silva, S. U. de
Object Type: Article
System: The UNT Digital Library