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Using EnergyPlus to Perform Dehumidification Analysis on Building America Homes: Preprint (open access)

Using EnergyPlus to Perform Dehumidification Analysis on Building America Homes: Preprint

A parametric study was conducted using EnergyPlus version 6.0 to investigate humidity issues on a typical mid-1990s reference home, a 2006 International Energy Conservation Code home, and a high-performance home in a hot-humid climate. The impacts of various dehumidification equipment and controls are analyzed on the high performance home. The study examined the combined effects of infiltration and mechanical ventilation with balanced and unbalanced mechanical ventilation systems. Indoor relative humidity excursions were examined; specifically, the number of excursions, average excursion length, and maximum excursion length. Space relative humidity, thermal comfort, and whole-house source energy consumption were analyzed for indoor relative humidity set points of 50%, 55%, and 60%. The study showed and explained why similar trends of high humidity were observed in all three homes regardless of energy efficiency, and why humidity problems are not necessarily unique in high-performance homes. Thermal comfort analysis indicated that occupants are unlikely to notice indoor humidity problems. The study confirmed that supplemental dehumidification should be provided to maintain space relative humidity below 60% in a hot-humid climate.
Date: March 1, 2011
Creator: Fang, X.; Winkler, J. & Christensen, D.
Object Type: Article
System: The UNT Digital Library
Central Wind Forecasting Programs in North America by Regional Transmission Organizations and Electric Utilities: Revised Edition (open access)

Central Wind Forecasting Programs in North America by Regional Transmission Organizations and Electric Utilities: Revised Edition

The report and accompanying table addresses the implementation of central wind power forecasting by electric utilities and regional transmission organizations in North America. The first part of the table focuses on electric utilities and regional transmission organizations that have central wind power forecasting in place; the second part focuses on electric utilities and regional transmission organizations that plan to adopt central wind power forecasting in 2010. This is an update of the December 2009 report, NREL/SR-550-46763.
Date: March 1, 2011
Creator: Rogers, J. & Porter, K.
Object Type: Report
System: The UNT Digital Library
Energy Retrofit Field Study and Best Practices in a Hot-Humid Climate (open access)

Energy Retrofit Field Study and Best Practices in a Hot-Humid Climate

Energy efficiency improvement as a component of comprehensive renovation was investigated under U.S. Department of Energy (DOE) funding of the Building America Partnership for Improved Residential Construction (BA-PIRC). Researchers at the Florida Solar Energy Center (FSEC) worked with affordable housing partners renovating foreclosed homes built from the 1950's through the 2000's in the hot-humid climate (within the Southern census region), primarily in Florida. Researchers targeted a 30% improvement in whole-house energy efficiency along with the health and safety, durability, and comfort guidelines outlined in DOE's Builders Challenge Program (Version 1) Quality Criteria.
Date: March 1, 2013
Creator: McIvaine, J.; Sutherland, K. & Martin, E.
Object Type: Report
System: The UNT Digital Library
Advanced Fuels for LWRs: Fully-Ceramic Microencapsulated and Related Concepts FY 2012 Interim Report (open access)

Advanced Fuels for LWRs: Fully-Ceramic Microencapsulated and Related Concepts FY 2012 Interim Report

This report summarizes the progress in the Deep Burn project at Idaho National Laboratory during the first half of fiscal year 2012 (FY2012). The current focus of this work is on Fully-Ceramic Microencapsulated (FCM) fuel containing low-enriched uranium (LEU) uranium nitride (UN) fuel kernels. UO2 fuel kernels have not been ruled out, and will be examined as later work in FY2012. Reactor physics calculations confirmed that the FCM fuel containing 500 mm diameter kernels of UN fuel has positive MTC with a conventional fuel pellet radius of 4.1 mm. The methodology was put into place and validated against MCNP to perform whole-core calculations using DONJON, which can interpolate cross sections from a library generated using DRAGON. Comparisons to MCNP were performed on the whole core to confirm the accuracy of the DRAGON/DONJON schemes. A thermal fluid coupling scheme was also developed and implemented with DONJON. This is currently able to iterate between diffusion calculations and thermal fluid calculations in order to update fuel temperatures and cross sections in whole-core calculations. Now that the DRAGON/DONJON calculation capability is in place and has been validated against MCNP results, and a thermal-hydraulic capability has been implemented in the DONJON methodology, the work will …
Date: March 1, 2012
Creator: Sen, R. Sonat; Boer, Brian; Bess, John D.; Pope, Michael A. & Ougouag, Abderrafi M.
Object Type: Report
System: The UNT Digital Library
Local Energy Plans in Practice: Case Studies of Austin and Denver (open access)

Local Energy Plans in Practice: Case Studies of Austin and Denver

Examines the successes and difficulties that Denver, CO, and Austin, TX , experienced implementing citywide energy plans.
Date: March 1, 2011
Creator: Petersen, D.; Matthews, E. & Weingarden, M.
Object Type: Report
System: The UNT Digital Library
Tritium Formation and Mitigation in High-Temperature Reactor Systems (open access)

Tritium Formation and Mitigation in High-Temperature Reactor Systems

Tritium is a radiologically active isotope of hydrogen. It is formed in nuclear reactors by neutron absorption and ternary fission events and can subsequently escape into the environment. To prevent the tritium contamination of proposed reactor buildings and surrounding sites, this study examines the root causes and potential mitigation strategies for permeation of tritium (such as: materials selection, inert gas sparging, etc...). A model is presented that can be used to predict permeation rates of hydrogen through metallic alloys at temperatures from 450–750 degrees C. Results of the diffusion model are presented for a steady production of tritium
Date: March 1, 2013
Creator: Sabharwall, Piyush; Stoots, Carl & Schmutz, Hans A.
Object Type: Report
System: The UNT Digital Library
Improving Vehicle Efficiency, Reducing Dependence on Foreign Oil (Fact Sheet) (open access)

Improving Vehicle Efficiency, Reducing Dependence on Foreign Oil (Fact Sheet)

This fact sheet provides an overview of the U.S. Department of Energy's Vehicle Technologies Program. Today, the United States spends about $400 billion each year on imported oil. To realize a secure energy future, America must break its dependence on imported oil and its volatile costs. The transportation sector accounts for about 70% of U.S. oil demand and holds tremendous opportunity to increase America's energy security by reducing oil consumption. That's why the U.S. Department of Energy (DOE) conducts research and development (R and D) on vehicle technologies which can stem America's dependence on oil, strengthen the economy, and protect the environment. Hybrid-electric and plug-in hybrid-electric vehicles can significantly improve fuel economy, displacing petroleum. Researchers are making batteries more affordable and recyclable, while enhancing battery range, performance, and life. This research supports President Obama's goal of putting 1 million electric vehicles on the road by 2015. The program is also working with businesses to develop domestic battery and electric-drive component plants to improve America's economic competitiveness globally. The program facilitates deployment of alternative fuels (ethanol, biodiesel, hydrogen, electricity, propane, and natural gas) and fuel infrastructures by partnering with state and local governments, universities, and industry. Reducing vehicle weight directly improves …
Date: March 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The effect of chrome adhesion layer on quartz resonator aging. (open access)

The effect of chrome adhesion layer on quartz resonator aging.

This SAND report documents a late start LDRD designed to determine the possible aging effects of a quartz resonator gold adhesion layer. Sandia uses quartz resonators for applications. These applications require a very stable frequency source with excellent aging (low drift) characteristics. These parts are manufactured by one of our qualified vendors outside Sandia Laboratories, Statek Corp. Over the years we, Sandia and the vendor, have seen aging variations that have not been completely explained by the typical mechanisms known in the industry. One theory was that the resonator metallization may be contributing to the resonator aging. This LDRD would allow us to test and analyze a group of resonators with known differentiating metallization and via accelerated aging determine if a chrome adhesion layer used to accept the final gold plating may contribute to poor aging. We worked with our main vendor to design and manufacture a set of quartz resonators with a wide range of metallization thickness ratios between the chrome and gold that will allow us determine the cause of this aging and which plating thickness ratios provide the best aging performance while not degrading other key characteristics.
Date: March 1, 2011
Creator: Wessendorf, Kurt O. & Ohlhausen, James Anthony
Object Type: Report
System: The UNT Digital Library
Fresh-Core Reload of the Neutron Radiography (NRAD) Reactor with Uranium(20)-Erbium-Zirconium-Hydride Fuel (open access)

Fresh-Core Reload of the Neutron Radiography (NRAD) Reactor with Uranium(20)-Erbium-Zirconium-Hydride Fuel

The neutron radiography (NRAD) reactor is a 250 kW TRIGA® (Training, Research, Isotopes, General Atomics) Mark II , tank-type research reactor currently located in the basement, below the main hot cell, of the Hot Fuel Examination Facility (HFEF) at the Idaho National Laboratory (INL). It is equipped with two beam tubes with separate radiography stations for the performance of neutron radiography irradiation on small test components. The initial critical configuration developed during the fuel loading process, which contains only 56 fuel elements, has been evaluated as an acceptable benchmark experiment. The 60-fuel-element operational core configuration of the NRAD LEU TRIGA reactor has also been evaluated as an acceptable benchmark experiment. Calculated eigenvalues differ significantly (~±1%) from the benchmark eigenvalue and have demonstrated sensitivity to the thermal scattering treatment of hydrogen in the U-Er-Zr-H fuel.
Date: March 1, 2013
Creator: Bess, John D.; Maddock, Thomas L.; Marshall, Margaret A. & Montierth, Leland M.
Object Type: Report
System: The UNT Digital Library
Aligned mesoporous architectures and devices. (open access)

Aligned mesoporous architectures and devices.

This is the final report for the Presidential Early Career Award for Science and Engineering - PECASE (LDRD projects 93369 and 118841) awarded to Professor Yunfeng Lu (Tulane University and University of California-Los Angeles). During the last decade, mesoporous materials with tunable periodic pores have been synthesized using surfactant liquid crystalline as templates, opening a new avenue for a wide spectrum of applications. However, the applications are somewhat limited by the unfavorabe pore orientation of these materials. Although substantial effort has been devoted to align the pore channels, fabrication of mesoporous materials with perpendicular pore channels remains challenging. This project focused on fabrication of mesoporous materials with perpendicularly aligned pore channels. We demonstrated structures for use in water purification, separation, sensors, templated synthesis, microelectronics, optics, controlled release, and highly selective catalysts.
Date: March 1, 2011
Creator: Brinker, C. Jeffrey & Lu, Yunfeng (University of California Los Angeles, Los Angeles, CA)
Object Type: Report
System: The UNT Digital Library
Awareness, Preference, Utilization, and Messaging Research for the Spallation Neutron Source and High Flux Isotope Reactor (open access)

Awareness, Preference, Utilization, and Messaging Research for the Spallation Neutron Source and High Flux Isotope Reactor

Oak Ridge National Laboratory (ORNL) offers the scientific community unique access to two types of world-class neutron sources at a single site - the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR). The 85-MW HFIR provides one of the highest steady-state neutron fluxes of any research reactor in the world, and the SNS is one of the world's most intense pulsed neutron beams. Management of these two resources is the responsibility of the Neutron Sciences Directorate (NScD). NScD commissioned this survey research to develop baseline information regarding awareness of and perceptions about neutron science. Specific areas of investigative interest include the following: (1) awareness levels among those in the scientific community about the two neutron sources that ORNL offers; (2) the level of understanding members of various scientific communities have regarding benefits that neutron scattering techniques offer; and (3) any perceptions that negatively impact utilization of the facilities. NScD leadership identified users of two light sources in North America - the Advanced Photon Source (APS) at Argonne National Laboratory and the National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory - as key publics. Given the type of research in which these scientists engage, they would quite …
Date: March 1, 2011
Creator: Bryant, Rebecca & Kszos, Lynn A
Object Type: Report
System: The UNT Digital Library
STUDY ON AIR INGRESS MITIGATION METHODS IN THE VERY HIGH TEMPERATURE GAS COOLED REACTOR (VHTR) (open access)

STUDY ON AIR INGRESS MITIGATION METHODS IN THE VERY HIGH TEMPERATURE GAS COOLED REACTOR (VHTR)

An air-ingress accident followed by a pipe break is considered as a critical event for a very high temperature gas-cooled reactor (VHTR). Following helium depressurization, it is anticipated that unless countermeasures are taken, air will enter the core through the break leading to oxidation of the in-core graphite structure. Thus, without mitigation features, this accident might lead to severe exothermic chemical reactions of graphite and oxygen. Under extreme circumstances, a loss of core structural integrity may occur along with excessive release of radiological inventory. Idaho National Laboratory under the auspices of the U.S. Department of Energy is performing research and development (R&D) that focuses on key phenomena important during challenging scenarios that may occur in the VHTR. Phenomena Identification and Ranking Table (PIRT) studies to date have identified the air ingress event, following on the heels of a VHTR depressurization, as very important (Oh et al. 2006, Schultz et al. 2006). Consequently, the development of advanced air ingress-related models and verification and validation (V&V) requirements are part of the experimental validation plan. This paper discusses about various air-ingress mitigation concepts applicable for the VHTRs. The study begins with identifying important factors (or phenomena) associated with the air-ingress accident by using …
Date: March 1, 2011
Creator: Oh, Chang H.
Object Type: Article
System: The UNT Digital Library
Energy Use Intensity and its Influence on the Integrated Daylighting Design of a Large Net Zero Energy Building: Preprint (open access)

Energy Use Intensity and its Influence on the Integrated Daylighting Design of a Large Net Zero Energy Building: Preprint

Net-zero energy buildings generate as much energy as they consume and are significant in the sustainable future of building design and construction. The role of daylighting (and its simulation) in the design process becomes critical. In this paper we present the process the National Renewable Energy Laboratory embarked on in the procurement, design, and construction of its newest building, the Research Support Facility (RSF) - particularly the roles of daylighting, electric lighting, and simulation. With a rapid construction schedule, the procurement, design, and construction had to be tightly integrated; with low energy use. We outline the process and measures required to manage a building design that could expect to operate at an efficiency previously unheard of for a building of this type, size, and density. Rigorous simulation of the daylighting and the electric lighting control response was a given, but the oft-ignored disconnect between lighting simulation and whole-building energy use simulation had to be addressed. The RSF project will be thoroughly evaluated for its performance for one year; preliminary data from the postoccupancy monitoring efforts will also be presented with an eye toward the current efficacy of building energy and lighting simulation.
Date: March 1, 2011
Creator: Guglielmetti , R.; Scheib, J.; Pless, S. D.; Torcellini , P. & Petro, R.
Object Type: Article
System: The UNT Digital Library
Systems analysis of past, present, and future chemical terrorism scenarios. (open access)

Systems analysis of past, present, and future chemical terrorism scenarios.

Throughout history, as new chemical threats arose, strategies for the defense against chemical attacks have also evolved. As a part of an Early Career Laboratory Directed Research and Development project, a systems analysis of past, present, and future chemical terrorism scenarios was performed to understand how the chemical threats and attack strategies change over time. For the analysis, the difficulty in executing chemical attack was evaluated within a framework of three major scenario elements. First, historical examples of chemical terrorism were examined to determine how the use of chemical threats, versus other weapons, contributed to the successful execution of the attack. Using the same framework, the future of chemical terrorism was assessed with respect to the impact of globalization and new technologies. Finally, the efficacy of the current defenses against contemporary chemical terrorism was considered briefly. The results of this analysis justify the need for continued diligence in chemical defense.
Date: March 1, 2012
Creator: Hoette, Trisha Marie
Object Type: Report
System: The UNT Digital Library
Dipole corrector magnets for the LBNE beam line (open access)

Dipole corrector magnets for the LBNE beam line

The conceptual design of a new dipole corrector magnet has been thoroughly studied. The planned Long-Baseline Neutrino Experiment (LBNE) beam line will require correctors capable of greater range and linearity than existing correctors, so a new design is proposed based on the horizontal trim dipole correctors built for the Main Injector synchrotron at Fermilab. The gap, pole shape, length, and number of conductor turns remain the same. To allow operation over a wider range of excitations without overheating, the conductor size is increased, and to maintain better linearity, the back leg thickness is increased. The magnetic simulation was done using ANSYS to optimize the shape and the size of the yoke. The thermal performance was also modeled and analyzed.
Date: March 1, 2011
Creator: Yu, M.; Velev, G.; Harding, D. & /Fermilab
Object Type: Article
System: The UNT Digital Library
Recycler barrier RF buckets (open access)

Recycler barrier RF buckets

The Recycler Ring at Fermilab uses a barrier rf systems for all of its rf manipulations. In this paper, I will give an overview of historical perspective on barrier rf system, the longitudinal beam dynamics issues, aspects of rf linearization to produce long flat bunches and methods used for emittance measurements of the beam in the RR barrier rf buckets. Current rf manipulation schemes used for antiproton beam stacking and longitudinal momentum mining of the RR beam for the Tevatron collider operation are explained along with their importance in spectacular success of the Tevatron luminosity performance.
Date: March 1, 2011
Creator: Bhat, C. M.
Object Type: Report
System: The UNT Digital Library
Unraveling the nature of charge excitations in La2CuO4 with momentum-resolved Cu K-edge resonant inelastic X-ray scattering (open access)

Unraveling the nature of charge excitations in La2CuO4 with momentum-resolved Cu K-edge resonant inelastic X-ray scattering

Results of model calculations using exact diagonalization reveal the orbital character of states associated with different Raman loss peaks in Cu K-edge resonant inelastic X-ray scattering (RIXS) from La{sub 2}CuO{sub 4}. The model includes electronic orbitals necessary to highlight non-local Zhang-Rice singlet, charge transfer and d-d excitations, as well as states with apical oxygen 2p{sub z} character. The dispersion of these excitations is discussed with prospects for resonant final state wave-function mapping. A good agreement with experiments emphasizes the substantial multi-orbital character of RIXS profiles in the energy transfer range 1-6 eV.
Date: March 1, 2011
Creator: Chen, Cheng-Chien
Object Type: Article
System: The UNT Digital Library
First high power pulsed tests of a dressed 325 MHz superconducting single spoke resonator at Fermilab (open access)

First high power pulsed tests of a dressed 325 MHz superconducting single spoke resonator at Fermilab

In the recently commissioned superconducting RF cavity test facility at Fermilab (SCTF), a 325 MHz, {beta} = 0.22 superconducting single-spoke resonator (SSR1) has been tested for the first time with its input power coupler. Previously, this cavity had been tested CW with a low power, high Q{sub ext} test coupler; first as a bare cavity in the Fermilab Vertical Test Stand and then fully dressed in the SCTF. For the tests described here, the design input coupler with Q{sub ext} {approx} 10{sup 6} was used. Pulsed power was provided by a Toshiba E3740A 2.5 MW klystron.
Date: March 1, 2011
Creator: Madrak, R.; Branlard, J.; Chase, B.; Darve, C.; Joireman, P.; Khabiboulline, T. et al.
Object Type: Article
System: The UNT Digital Library
SCALE ANALYSIS OF CONVECTIVE MELTING WITH INTERNAL HEAT GENERATION (open access)

SCALE ANALYSIS OF CONVECTIVE MELTING WITH INTERNAL HEAT GENERATION

Using a scale analysis approach, we model phase change (melting) for pure materials which generate internal heat for small Stefan numbers (approximately one). The analysis considers conduction in the solid phase and natural convection, driven by internal heat generation, in the liquid regime. The model is applied for a constant surface temperature boundary condition where the melting temperature is greater than the surface temperature in a cylindrical geometry. We show the time scales in which conduction and convection heat transfer dominate.
Date: March 1, 2011
Creator: Crepeau, John
Object Type: Article
System: The UNT Digital Library
Establishment of Small Wind Regional Test Centers: Preprint (open access)

Establishment of Small Wind Regional Test Centers: Preprint

The rapid growth of the small wind turbine (SWT) market is attracting numerous entrants. Small wind turbine purchasers now have many options but often lack information (such as third-party certification) to select a quality turbine. Most SWTs do not have third-party certification due to the expense and difficulty of the certification process. Until recently, the only SWT certification bodies were in Europe. In North America, testing has been limited to a small number of U.S. Department of Energy (DOE) subsidized tests conducted at the National Wind Technology Center (NWTC) under the ongoing Independent Testing Project. Within the past few years, the DOE, National Renewable Energy Lab (NREL), and some states have worked with the North American SWT industry to create a SWT certification infrastructure. The goal is to increase the number of certified turbines and gain greater consumer confidence in SWT technology. The American Wind Energy Association (AWEA) released the AWEA Small Wind Turbine Performance and Safety Standard (AWEA Standard 9.1 - 2009) in December 2009. The Small Wind Certification Council (SWCC), a North American certification body, began accepting applications for certification to the AWEA standard in February 2010. To reduce certification testing costs, DOE/NREL is providing financial and technical …
Date: March 1, 2011
Creator: Jimenez, T.; Forsyth, T.; Huskey, A.; Mendoza, I.; Sinclair, K. & Smith, J.
Object Type: Article
System: The UNT Digital Library
High Efficiency, Low Cost Solar Cells Manufactured Using 'Silicon Ink' on Thin Crystalline Silicon Wafers (open access)

High Efficiency, Low Cost Solar Cells Manufactured Using 'Silicon Ink' on Thin Crystalline Silicon Wafers

Reported are the development and demonstration of a 17% efficient 25mm x 25mm crystalline Silicon solar cell and a 16% efficient 125mm x 125mm crystalline Silicon solar cell, both produced by Ink-jet printing Silicon Ink on a thin crystalline Silicon wafer. To achieve these objectives, processing approaches were developed to print the Silicon Ink in a predetermined pattern to form a high efficiency selective emitter, remove the solvents in the Silicon Ink and fuse the deposited particle Silicon films. Additionally, standard solar cell manufacturing equipment with slightly modified processes were used to complete the fabrication of the Silicon Ink high efficiency solar cells. Also reported are the development and demonstration of a 18.5% efficient 125mm x 125mm monocrystalline Silicon cell, and a 17% efficient 125mm x 125mm multicrystalline Silicon cell, by utilizing high throughput Ink-jet and screen printing technologies. To achieve these objectives, Innovalight developed new high throughput processing tools to print and fuse both p and n type particle Silicon Inks in a predetermined pat-tern applied either on the front or the back of the cell. Additionally, a customized Ink-jet and screen printing systems, coupled with customized substrate handling solution, customized printing algorithms, and a customized ink drying process, …
Date: March 1, 2011
Creator: Antoniadis, H.
Object Type: Report
System: The UNT Digital Library
Interim Results from a Study of the Impacts of Tin (II) Based Mercury Treatment in a Small Stream Ecosystem: Tims Branch, Savannah River Site (open access)

Interim Results from a Study of the Impacts of Tin (II) Based Mercury Treatment in a Small Stream Ecosystem: Tims Branch, Savannah River Site

A research team is assessing the impacts of an innovative mercury treatment system in Tims Branch, a small southeastern stream. The treatment system, installed in 2007, reduces and removes inorganic mercury from water using tin(II) (stannous) chloride addition followed by air stripping. The system results in discharge of inorganic tin to the ecosystem. This screening study is based on historical information combined with measurements of contaminant concentrations in water, fish, sediment, biofilms and invertebrates. Initial mercury data indicate that first few years of mercury treatment resulted in a significant decrease in mercury concentration in an upper trophic level fish, redfin pickerel, at all sampling locations in the impacted reach. For example, the whole body mercury concentration in redfin pickerel collected from the most impacted pond decreased approximately 72% between 2006 (pre-treatment) and 2010 (post-treatment). Over this same period, mercury concentrations in the fillet of redfin pickerel in this pond were estimated to have decreased from approximately 1.45 {micro}g/g (wet weight basis) to 0.45 {micro}g/g - a decrease from 4.8x to 1.5x the current EPA guideline concentration for mercury in fillet (0.3 {micro}g/g). Thermodynamic modeling, scanning electron microscopy, and other sampling data for tin suggest that particulate tin (IV) oxides are …
Date: March 1, 2012
Creator: Looney, Brian B.; Kling, David; Mills, Gary L.; Bryan, L., Jr.; Mathews, Teresa J.; Peterson, Mark J. et al.
Object Type: Report
System: The UNT Digital Library
Hydra-TH Simulation of Single-Phase Flow and Heat (open access)

Hydra-TH Simulation of Single-Phase Flow and Heat

The focus of this report is on the comparison of n
Date: March 1, 2013
Creator: Bui, Anh & Zhang, Hongbin
Object Type: Report
System: The UNT Digital Library