UPGRADING THE CEBAF INJECTOR WITH A NEW BOOSTER, HIGHER VOLTAGE GUN, AND HIGHER FINAL ENERGY (open access)

UPGRADING THE CEBAF INJECTOR WITH A NEW BOOSTER, HIGHER VOLTAGE GUN, AND HIGHER FINAL ENERGY

The Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab will be upgraded from 6 GeV to 12 GeV in the next few years. To meet the requirement of the new machine and to take the opportunity to improve the beam quality, the CEBAF injector will be upgraded with a higher voltage gun, a new booster, and a new accelerating RF module. The CEBAF injector creates and accelerates three beams at different currents simultaneously. The beams are interleaved, each at one third of the RF frequency, traveling through the same beam line. The higher voltage gun will lower the space charge effects. The new booster with optimized beam dynamics will complete the bunching process and provide initial acceleration matched to the new gun voltage. Using our latest SRF design, the new booster has significantly lower x/y coupling effects that should improve our beam setup and operation for the highly sensitive parity experiments scheduled for the CEBAF's future. Finally, the new accelerating RF module will roughly double the injector final energy to match the rest of the 12 GeV accelerator. In this paper we will provide more detail about this upgrade.
Date: July 1, 2012
Creator: Kazimi, Reza; Freyberger, Arne; Hofler, Alicia; Hutton, Andrew & Hannon, Fay
Object Type: Article
System: The UNT Digital Library
USE OF SILICON CARBIDE MONITORS IN ATR IRRADIATION TESTING (open access)

USE OF SILICON CARBIDE MONITORS IN ATR IRRADIATION TESTING

In April 2007, the Department of Energy (DOE) designated the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF) to advance US leadership in nuclear science and technology. By attracting new users from universities, laboratories, and industry, the ATR will support basic and applied nuclear research and development and help address the nation's energy security needs. In support of this new program, the Idaho National Laboratory (INL) has developed in-house capabilities to fabricate, test, and qualify new and enhanced temperature sensors for irradiation testing. Although most efforts emphasize sensors capable of providing real-time data, selected tasks have been completed to enhance sensors provided in irradiation locations where instrumentation leads cannot be included, such as drop-in capsule and Hydraulic Shuttle Irradiation System (HSIS) or 'rabbit' locations. For example, silicon carbide (SiC) monitors are now available to detect peak irradiation temperatures between 200°C and 800°C. Using a resistance measurement approach, specialized equipment installed at INL's High Temperature Test Laboratory (HTTL) and specialized procedures were developed to ensure that accurate peak irradiation temperature measurements are inferred from SiC monitors irradiated at the ATR. Comparison examinations were completed by INL to demonstrate this capability, and several programs currently rely on SiC monitors for …
Date: July 1, 2012
Creator: Davis, K. L.; Chase, B.; Unruh, T.; Knudson, D. & Rempe, J. L.
Object Type: Article
System: The UNT Digital Library
Status of Proof-of-principle Experiment for Coherent Electron Cooling (open access)

Status of Proof-of-principle Experiment for Coherent Electron Cooling

Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, high-intensity hadron colliders. To verify the concept we conduct proof-of-the-principle experiment at RHIC. In this paper, we describe the current experimental setup to be installed into 2 o'clock RHIC interaction regions. We present current design, status of equipment acquisition and estimates for the expected beam parameters.
Date: July 1, 2012
Creator: Pinayev, I.; Ben-Zvi, Ilan; Bengtsson, J.; Elizarov, A.; Fedotov, A. V.; Gassner, D. M. et al.
Object Type: Article
System: The UNT Digital Library
Investigating the performance of catalyst layer micro-structures with different platinum loadings (open access)

Investigating the performance of catalyst layer micro-structures with different platinum loadings

In this study a four-phase micro-structure of a PEFC catalyst layer was reconstructed by randomly placing overlapping spheres for each solid catalyst phase. The micro-structure was mirrored to make a micro-structure. A body-fit computational mesh was produced for the reconstructed micro-structure in OpenFOAM. Associated conservation equations were solved within all the phases with electrochemical reaction as the boundary condition at the interface between ionomer and platinum phases. The study is focused on the platinum loading of CL. The polarization curves of the micro-structure performance have been compared for different platinum loadings. This paper gives increased insight into the relatively greater losses at decreased platinum loadings.
Date: July 1, 2012
Creator: Khakaz-Baboli, Moben; Harvey, David & Pharoah, Jon
Object Type: Article
System: The UNT Digital Library
Developing Government Renewable Energy Projects (open access)

Developing Government Renewable Energy Projects

The US Army Corps of Engineers has retained Idaho National Laboratory (INL) to conduct a study of past INL experiences and complete a report that identifies the processes that are needed for the development of renewable energy projects on government properties. The INL has always maintained expertise in power systems and applied engineering and INL’s renewable energy experiences date back to the 1980’s when our engineers began performing US Air Force wind energy feasibility studies and development projects. Over the last 20+ years of working with Department of Defense and other government agencies to study, design, and build government renewable projects, INL has experienced the do’s and don’ts for being successful with a project. These compiled guidelines for government renewable energy projects could include wind, hydro, geothermal, solar, biomass, or a variety of hybrid systems; however, for the purpose of narrowing the focus of this report, wind projects are the main topic discussed throughout this report. It is our thought that a lot of what is discussed could be applied, possibly with some modifications, to other areas of renewable energy. It is also important to note that individual projects (regardless the type) vary to some degree depending on location, size, …
Date: July 1, 2012
Creator: Myers, Kurt S.; Baldwin, Thomas L.; Bush, Jason W. & Gentle, Jake P.
Object Type: Report
System: The UNT Digital Library
Managing System of Systems Requirements with a Requirements Screening Group (open access)

Managing System of Systems Requirements with a Requirements Screening Group

Figuring out an effective and efficient way to manage not only your Requirement’s Baseline, but also the development of all your individual requirements during a Program’s/Project’s Conceptual and Development Life Cycle Stages can be both daunting and difficult. This is especially so when you are dealing with a complex and large System of Systems (SoS) Program with potentially thousands and thousands of Top Level Requirements as well as an equal number of lower level System, Subsystem and Configuration Item requirements that need to be managed. This task is made even more overwhelming when you have to add in integration with multiple requirements’ development teams (e.g., Integrated Product Development Teams (IPTs)) and/or numerous System/Subsystem Design Teams. One solution for tackling this difficult activity on a recent large System of Systems Program was to develop and make use of a Requirements Screening Group (RSG). This group is essentially a Team made up of co-chairs from the various Stakeholders with an interest in the Program of record that are enabled and accountable for Requirements Development on the Program/Project. The RSG co-chairs, often with the help of individual support team, work together as a Program Board to monitor, make decisions on, and provide guidance …
Date: July 1, 2012
Creator: Barden, Ronald R.
Object Type: Article
System: The UNT Digital Library
Tritium Permeability of Incoloy 800H and Inconel 617 (open access)

Tritium Permeability of Incoloy 800H and Inconel 617

Design of the Next Generation Nuclear Plant (NGNP) reactor and its high-temperature components requires information regarding the permeation of fission generated tritium and hydrogen product through candidate heat exchanger alloys. Release of fission-generated tritium to the environment and the potential contamination of the helium coolant by permeation of product hydrogen into the coolant system represent safety basis and product contamination issues. Of the three potential candidates for high-temperature components of the NGNP reactor design, only permeability for Incoloy 800H has been well documented. Hydrogen permeability data have been published for Inconel 617, but only in two literature reports and for partial pressures of hydrogen greater than one atmosphere, far higher than anticipated in the NGNP reactor. To support engineering design of the NGNP reactor components, the tritium permeability of Inconel 617 and Incoloy 800H was determined using a measurement system designed and fabricated at Idaho National Laboratory. The tritium permeability of Incoloy 800H and Inconel 617, was measured in the temperature range 650 to 950°C and at primary concentrations of 1.5 to 6 parts per million volume tritium in helium. (partial pressures of 10-6 atm)—three orders of magnitude lower partial pressures than used in the hydrogen permeation testing. The measured …
Date: July 1, 2012
Creator: Winston, Philip; Calderoni, Pattrick & Humrickhouse, Paul
Object Type: Report
System: The UNT Digital Library
Raising Photoemission Efficiency with Surface Acoustic Waves (open access)

Raising Photoemission Efficiency with Surface Acoustic Waves

We are developing a novel technique that may help increase the efficiency and reduce costs of photoelectron sources used at electron accelerators. The technique is based on the use of Surface Acoustic Waves (SAW) in piezoelectric materials, such as GaAs, that are commonly used as photocathodes. Piezoelectric fields produced by the traveling SAW spatially separate electrons and holes, reducing their probability of recombination, thereby enhancing the photoemission quantum efficiency of the photocathode. Additional advantages could be increased polarization provided by the enhanced mobility of charge carriers that can be controlled by the SAW and the ionization of optically-generated excitons resulting in the creation of additional electron-hole pairs. It is expected that these novel features will reduce the cost of accelerator operation. A theoretical model for photoemission in the presence of SAW has been developed, and experimental tests of the technique are underway.
Date: July 1, 2012
Creator: A. Afanasev, F. Hassani, C.E. Korman, V.G. Dudnikov, R.P. Johnson, M. Poelker, K.E.L. Surles-Law
Object Type: Article
System: The UNT Digital Library
Statistical Simulation of the Performance and Degradation of a PEMFC Membrane Electrode Assembly (open access)

Statistical Simulation of the Performance and Degradation of a PEMFC Membrane Electrode Assembly

A 1-D MEA Performance model was developed that considered transport of liquid water, agglomerate catalyst structure, and the statistical variation of the MEA characteristic parameters. The model was validated against a low surface area carbon supported catalyst across various platinum loadings and operational conditions. The statistical variation was found to play a significant role in creating noise in the validation data and that there was a coupling effect between movement in material properties with liquid water transport. Further, in studying the low platinum loaded catalyst layers it was found that liquid water played a significant role in the increasing the overall transport losses. The model was then further applied to study platinum dissolution via potential cycling accelerated stress tests, in which the platinum was found to dissolve nearest the membrane effectively resulting in reaction distribution shifts within the layer.
Date: July 1, 2012
Creator: Harvey, David; Bellemare-Davis, Alexander; Karan, Kunal; Jayansankar, Barath; Pharoah, Jon; Colbow, Vesna et al.
Object Type: Article
System: The UNT Digital Library
Improving EM&V for Energy Efficiency Programs (Fact Sheet) (open access)

Improving EM&V for Energy Efficiency Programs (Fact Sheet)

This fact sheet describes the objectives of the U.S. Department of Energy Uniform Methods Project to bring consistency to energy savings calculations in U.S. energy efficiency programs. The U.S. Department of Energy (DOE) is developing a framework and a set of protocols for determining gross energy savings from energy efficiency measures and programs. The protocols represent a refinement of the body of knowledge supporting energy efficiency evaluation, measurement, and verification (EM&V) activities. They have been written by technical experts within the field and reviewed by industry experts. Current EM&V practice allows for multiple methods for calculating energy savings. These methods were developed to meet the needs of energy efficiency program administrators and regulators. Although they served their original objectives well, they have resulted in inconsistent and incomparable savings results - even for identical measures. The goal of the Uniform Methods Project is to strengthen the credibility of energy savings determinations by improving EM&V, increasing the consistency and transparency of how energy savings are determined.
Date: July 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Measure Guideline: Internal Insulation of Masonry Walls (open access)

Measure Guideline: Internal Insulation of Masonry Walls

This measure guideline provides recommendations for interior insulation assemblies that control interstitial condensation and durability risks; recommendations for acceptable thermal performance are also provided. An illustrated guide of high-risk exterior details (which concentrate bulk water), and recommended remediation details is provided. This is followed by a recommended methodology for risk assessment of a masonry interior insulation project: a series of steps are suggested to assess the risks associated with this retrofit, with greater certainty with added steps.
Date: July 1, 2012
Creator: Straube, J. F.; Ueno, K. & Schumacher, C. J.
Object Type: Report
System: The UNT Digital Library
Solar Radiation Research Laboratory (Poster) (open access)

Solar Radiation Research Laboratory (Poster)

SunShot Initiative awardee posters describing the different technologies within the four subprograms of the DOE Solar Program (Photovoltaics, Concentrating Solar Power, Soft Costs, and Systems Integration).
Date: July 1, 2012
Creator: Stoffel, T.; Andreas, A.; Reda, I.; Dooraghi, M.; Habte, A.; Kutchenreiter, M. et al.
Object Type: Article
System: The UNT Digital Library

Role of Smarter Grids in Variable Renewable Resource Integration

This presentation discusses the role of smarter grids in variable renewable resource integration and references material from a forthcoming ISGAN issue paper: Smart Grid Contributions to Variable Renewable Resource Integration, co-written by the presenter and currently in review.
Date: July 1, 2012
Creator: Miller, M.
Object Type: Presentation
System: The UNT Digital Library
LIDAR Wind Speed Measurements of Evolving Wind Fields (open access)

LIDAR Wind Speed Measurements of Evolving Wind Fields

Light Detection and Ranging (LIDAR) systems are able to measure the speed of incoming wind before it interacts with a wind turbine rotor. These preview wind measurements can be used in feedforward control systems designed to reduce turbine loads. However, the degree to which such preview-based control techniques can reduce loads by reacting to turbulence depends on how accurately the incoming wind field can be measured. Past studies have assumed Taylor's frozen turbulence hypothesis, which implies that turbulence remains unchanged as it advects downwind at the mean wind speed. With Taylor's hypothesis applied, the only source of wind speed measurement error is distortion caused by the LIDAR. This study introduces wind evolution, characterized by the longitudinal coherence of the wind, to LIDAR measurement simulations to create a more realistic measurement model. A simple model of wind evolution is applied to a frozen wind field used in previous studies to investigate the effects of varying the intensity of wind evolution. LIDAR measurements are also evaluated with a large eddy simulation of a stable boundary layer provided by the National Center for Atmospheric Research. Simulation results show the combined effects of LIDAR errors and wind evolution for realistic turbine-mounted LIDAR measurement scenarios.
Date: July 1, 2012
Creator: Simley, E. & Pao, L. Y.
Object Type: Report
System: The UNT Digital Library
Rising Above the Water: New Orleans Implements Energy Efficiency and Sustainability Practices Following Hurricanes Katrina and Rita (Fact Sheet) (open access)

Rising Above the Water: New Orleans Implements Energy Efficiency and Sustainability Practices Following Hurricanes Katrina and Rita (Fact Sheet)

This fact sheet describes the technical assistance that the U.S. Department of Energy, through its National Renewable Energy Laboratory, provided to New Orleans, Louisiana, which helped the city incorporate energy efficiency into its rebuilding efforts for K-12 schools and homes following Hurricanes Katrina and Rita. NREL also provided support and analysis on energy policy efforts.
Date: July 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Fast-neutron coded-aperture imaging of special nuclear material configurations (open access)

Fast-neutron coded-aperture imaging of special nuclear material configurations

In the past year, a prototype fast-neutron coded-aperture imager has been developed that has sufficient efficiency and resolution to make the counting of warheads for possible future treaty confirmation scenarios via their fission-neutron emissions practical. The imager is constructed from custom-built pixelated liquid scintillator detectors. The liquid scintillator detectors enable neutron-gamma discrimination via pulse shape, and the pixelated construction enables a sufficient number of pixels for imaging in a compact detector with a manageable number of channels of readout electronics. The imager has been used to image neutron sources at ORNL, special nuclear material (SNM) sources at the Idaho National Laboratory (INL) Zero Power Physics Reactor (ZPPR) facility, and neutron source and shielding configurations at Sandia National Laboratories. This paper reports on the design and construction of the imager, characterization measurements with neutron sources at ORNL, and measurements with SNM at the INL ZPPR facility.
Date: July 1, 2012
Creator: Hausladen, P. A.; Blackston, M. A.; Brubaker, E.; Chichester, D. L.; Marleau, P. & Newby, R. J.
Object Type: Article
System: The UNT Digital Library
HIGH POWER TEST OF RF SEPARATOR FOR 12 GEV UPGRADE OF CEBAF AT JLAB (open access)

HIGH POWER TEST OF RF SEPARATOR FOR 12 GEV UPGRADE OF CEBAF AT JLAB

CEBAF at JLab is in the process of an energy upgrade from 6 GeV to 12 GeV. The existing setup of the RF separator cavities in the 5th pass will not be adequate to extract the highest energy (11 GeV) beam to any two existing halls (A, B or C) while simultaneously delivering to the new hall D in the case of the proposed 12 GeV upgrade of the machine. To restore this capability, we are exploring the possibility of extension of existing normal conducting 499 MHz TEM-type rf separator cavities. Detailed numerical studies suggest that six 2-cell normal conducting structures meet the requirements; each 2-cell structure will require up to 4 kW RF input power in contrast with the current nominal operating power of 1.0 to 2.0 kW. A high power test of 4 kW confirms that the cavity meet the requirement.
Date: July 1, 2012
Creator: Ahmed, S.; Wissmann, M.; Mammosser, J.; Hovater, C.; Spata, M.; Krafft, G. et al.
Object Type: Article
System: The UNT Digital Library
Studies of the Twin Helix Parametric-resonance Ionization Cooling Channel with COSY INFINITY (open access)

Studies of the Twin Helix Parametric-resonance Ionization Cooling Channel with COSY INFINITY

A primary technical challenge to the design of a high luminosity muon collider is an effective beam cooling system. An epicyclic twin-helix channel utilizing parametric-resonance ionization cooling has been proposed for the final 6D cooling stage. A proposed design of this twin-helix channel is presented that utilizes correlated optics between the horizontal and vertical betatron periods to simultaneously focus transverse motion of the beam in both planes. Parametric resonance is induced in both planes via a system of helical quadrupole harmonics. Ionization cooling is achieved via periodically placed wedges of absorbing material, with intermittent rf cavities restoring longitudinal momentum necessary to maintain stable orbit of the beam. COSY INFINITY is utilized to simulate the theory at first order. The motion of particles around a hyperbolic fixed point is tracked. Comparison is made between the EPIC cooling channel and standard ionization cooling effects. Cooling effects are measured, after including stochastic effects, for both a single particle and a distribution of particles.
Date: July 1, 2012
Creator: J.A. Maloney, K.B. Beard, R.P. Johnson, A. Afanasev, S.A. Bogacz, Y.S. Derbenev, V.S. Morozov, B. Erdelyi
Object Type: Article
System: The UNT Digital Library
Verification and Validation of EnergyPlus Conduction Finite Difference and Phase Change Material Models for Opaque Wall Assemblies (open access)

Verification and Validation of EnergyPlus Conduction Finite Difference and Phase Change Material Models for Opaque Wall Assemblies

Phase change materials (PCMs) represent a potential technology to reduce peak loads and HVAC energy consumption in buildings. There are few building energy simulation programs that have the capability to simulate PCM but their accuracy has not been completely tested. This report summarizes NREL efforts to develop diagnostic tests cases to obtain accurate energy simulations when PCMs are modeled in residential buildings.
Date: July 1, 2012
Creator: Tabares-Velasco, P. C.; Christensen, C.; Bianchi, M. & Booten, C.
Object Type: Report
System: The UNT Digital Library
Development and assessment of solar-thermal-activated fuel production. Phase 1, summary. (open access)

Development and assessment of solar-thermal-activated fuel production. Phase 1, summary.

None
Date: July 1, 2012
Creator: Miller, James Edward; Allendorf, Mark D.; Ambrosini, Andrea; Coker, Eric Nicholas; Diver, Richard B., Jr. (, . Diver Solar, LLC, Albuquerque, NM); Ermanoski, Ivan et al.
Object Type: Report
System: The UNT Digital Library
Progress on muon parametric-resonance ionization cooling channel development (open access)

Progress on muon parametric-resonance ionization cooling channel development

Parametric-resonance Ionization Cooling (PIC) is intended as the final 6D cooling stage of a high-luminosity muon collider. To implement PIC, a continuous-field twin-helix magnetic channel was developed. A 6D cooling with stochastic effects off is demonstrated in a GEANT4/G4beamline model of a system where wedge-shaped Be absorbers are placed at the appropriate dispersion points in the twin-helix channel and are followed by short rf cavities. To proceed to cooling simulations with stochastics on, compensation of the beam aberrations from one absorber to another is required. Initial results on aberration compensation using a set of various-order continuous multipole fields are presented. As another avenue to mitigate the aberration effect, we optimize the cooling channel's period length. We observe a parasitic parametric resonance naturally occurring in the channel's horizontal plane due to the periodic beam energy modulation caused by the absorbers and rf. We discuss options for compensating this resonance and/or properly combining it with the induced half-integer parametric resonance needed for PIC.
Date: July 1, 2012
Creator: V.S. Morozov, Ya.S. Derbenev, A. Afanasev, K.B. Beard, R.P. Johnson, B. Erdelyi, J.A. Maloney
Object Type: Article
System: The UNT Digital Library
Comparison of Wind Power and Load Forecasting Error Distributions: Preprint (open access)

Comparison of Wind Power and Load Forecasting Error Distributions: Preprint

The introduction of large amounts of variable and uncertain power sources, such as wind power, into the electricity grid presents a number of challenges for system operations. One issue involves the uncertainty associated with scheduling power that wind will supply in future timeframes. However, this is not an entirely new challenge; load is also variable and uncertain, and is strongly influenced by weather patterns. In this work we make a comparison between the day-ahead forecasting errors encountered in wind power forecasting and load forecasting. The study examines the distribution of errors from operational forecasting systems in two different Independent System Operator (ISO) regions for both wind power and load forecasts at the day-ahead timeframe. The day-ahead timescale is critical in power system operations because it serves the unit commitment function for slow-starting conventional generators.
Date: July 1, 2012
Creator: Hodge, B. M.; Florita, A.; Orwig, K.; Lew, D. & Milligan, M.
Object Type: Article
System: The UNT Digital Library
Ground Testing a Nuclear Thermal Rocket: Design of a sub-scale demonstration experiment (open access)

Ground Testing a Nuclear Thermal Rocket: Design of a sub-scale demonstration experiment

In 2008, the NASA Mars Architecture Team found that the Nuclear Thermal Rocket (NTR) was the preferred propulsion system out of all the combinations of chemical propulsion, solar electric, nuclear electric, aerobrake, and NTR studied. Recently, the National Research Council committee reviewing the NASA Technology Roadmaps recommended the NTR as one of the top 16 technologies that should be pursued by NASA. One of the main issues with developing a NTR for future missions is the ability to economically test the full system on the ground. In the late 1990s, the Sub-surface Active Filtering of Exhaust (SAFE) concept was first proposed by Howe as a method to test NTRs at full power and full duration. The concept relied on firing the NTR into one of the test holes at the Nevada Test Site which had been constructed to test nuclear weapons. In 2011, the cost of testing a NTR and the cost of performing a proof of concept experiment were evaluated.
Date: July 1, 2012
Creator: Bedsun, David; Lee, Debra; Townsend, Margaret; Cooper, Clay A.; Chapman, Jennifer; Samborsky, Ronald et al.
Object Type: Article
System: The UNT Digital Library

In-Use Performance Results of Medium Duty Electric Vehicles

This presentation describes a DOE program to monitor and report on vehicle performance and energy utilization of medium-duty and heavy-duty electric vehicles.
Date: July 1, 2012
Creator: Walkowicz, K.
Object Type: Presentation
System: The UNT Digital Library