HCCI engine control by thermal management (open access)

HCCI engine control by thermal management

This work investigates a control system for HCCI engines, where thermal energy from exhaust gas recirculation (EGR) and compression work in the supercharger are either recycled or rejected as needed. HCCI engine operation is analyzed with a detailed chemical kinetics code, HCT (Hydrodynamics, Chemistry and Transport), that has been extensively modified for application to engines. HCT is linked to an optimizer that determines the operating conditions that result in maximum brake thermal efficiency, while meeting the restrictions of low NO{sub x} and peak cylinder pressure. The results show the values of the operating conditions that yield optimum efficiency as a function of torque and RPM. For zero torque (idle), the optimizer determines operating conditions that result in minimum fuel consumption. The optimizer is also used for determining the maximum torque that can be obtained within the operating restrictions of NO{sub x} and peak cylinder pressure. The results show that a thermally controlled HCCI engine can successfully operate over a wide range of conditions at high efficiency and low emissions.
Date: May 11, 2000
Creator: Martinez-Frias, J; Aceves, S M; Flowers, D; Smith, J R & Dibble, R
Object Type: Article
System: The UNT Digital Library
Tearing and MHD Instability During Gun Injection into a Spheromak (open access)

Tearing and MHD Instability During Gun Injection into a Spheromak

Linear stability analysis of a two-cylinder approximation to gun injection--one cylinder to represent the confined spheromak and another to represent the gun--is shown to yield equilibria in which tearing modes exist simultaneously at the magnetic axis and at the geometric (gun) axis, as might be required to sustain helicity injection. These equilibria are MHD stable at the two axes but may have localized MHD instability at an interior minimum in the q profile. The theory predicts two tearing thresholds with successively deeper q minima as the gun current is increased at constant bias flux.
Date: May 11, 2000
Creator: Fowler, T K
Object Type: Report
System: The UNT Digital Library
Hanford Site Climatological Data Summary 1999 with Historical Data (open access)

Hanford Site Climatological Data Summary 1999 with Historical Data

This document presents the climatological data measured at the Hanford Site for claendar year 1999. The information contained includes updated historical climatologies for temperature, precipitation, normal and extreme values of temperature and precipitaion and other meteorological parameters.
Date: May 11, 2000
Creator: Hoitink, Dana J.; Burk, Kenneth W. & Ramsdell, James V.
Object Type: Report
System: The UNT Digital Library
Waste Package Lifting Calculation (open access)

Waste Package Lifting Calculation

The objective of this calculation is to evaluate the structural response of the waste package during the horizontal and vertical lifting operations in order to support the waste package lifting feature design. The scope of this calculation includes the evaluation of the 21 PWR UCF (pressurized water reactor uncanistered fuel) waste package, naval waste package, 5 DHLW/DOE SNF (defense high-level waste/Department of Energy spent nuclear fuel)--short waste package, and 44 BWR (boiling water reactor) UCF waste package. Procedure AP-3.12Q, Revision 0, ICN 0, calculations, is used to develop and document this calculation.
Date: May 11, 2000
Creator: Marr, H.
Object Type: Report
System: The UNT Digital Library
Evaluating the Weatherization Assistance Program in Your State: A Manager's Guide (open access)

Evaluating the Weatherization Assistance Program in Your State: A Manager's Guide

Evaluations of the Weatherization Assistance Program (the Program) serve three major purposes: (1) to document the energy savings and cost effectiveness of the Program, (2) to attract and maintain funding, and (3) to identify opportunities for improving the Program's performance. State managers need detailed and specific information about the performance of their own Program if they are to conduct and market it as effectively as possible. In this evaluation guide, we focus almost entirely on the issues related to the measurement of energy savings. Because the Program's main goal is to reduce the energy use and energy burden of low-income households, the minimum output of an evaluation study should be an estimate of energy savings. If resources are limited, the first priority is to obtain this estimate of savings. Some states may be interested in other issues such as determining Program cost effectiveness, testing the value of various audit types, or identifying the best opportunities for increasing energy savings. Because of limited resources, most will focus only on measuring energy savings.
Date: May 11, 2000
Creator: Berry, L
Object Type: Report
System: The UNT Digital Library
Assessment of Cost Savings of DOE's Return-on-Investment Program (open access)

Assessment of Cost Savings of DOE's Return-on-Investment Program

The US Department of Energy (DOE) Office of Pollution Prevention (EM-77) created a successful internally competed program to fund innovative projects based on projected returns. This is called the Return-on-Investment (ROI) program. EM-77 conducted a successful ROI pilot, developed and implemented sound management practices, and successfully transferred the program to several Operations Offices. Over the past 4 years sites have completed 262 ROI projects (costing $18.8 million) with claimed first-year savings of $88 million and claimed life cycle savings exceeding $300 million. EM-77 requested that Oak Ridge National Laboratory perform an independent evaluation of the site-led, DOE-HQ-funded pollution prevention (P2) ROI program to assist the Department in determining whether claimed savings are real. The approach for conducting this evaluation was to analyze a sample of P2 projects to identify actual project cost savings and other actual benefits--e.g., amount of waste avoided. To determine the projects for review, EM-77 provided a list of EM-funded projects at two Operations Offices: Oak Ridge and Richland. Sixteen projects (eight from each Operations Office) were selected at random from this list for review. Project documentation was requested from the sites, and this was followed by face-to-face interviews with project personnel. of the 16 projects selected …
Date: May 11, 2000
Creator: Yuracko, K. L.
Object Type: Report
System: The UNT Digital Library
Acceptance Test Procedure for New Pumping Instrumentation and Control Skid R (open access)

Acceptance Test Procedure for New Pumping Instrumentation and Control Skid R

This Acceptance Test Procedure (ATP) provides for the inspection and testing of the new Pumping Instrumentation and Control (PIC) skid designed as ''R''. The ATP will be performed after the construction of the PIC skid in the fabrication shop.
Date: May 11, 2000
Creator: Koch, M. R.
Object Type: Report
System: The UNT Digital Library
Spent Nuclear Fuel (SNF) Project Canister Storage Building (CSB) Process Flow Diagram Mass Balance Calculations (open access)

Spent Nuclear Fuel (SNF) Project Canister Storage Building (CSB) Process Flow Diagram Mass Balance Calculations

The purpose of these calculations is to develop the material balances for documentation of the Canister Storage Building (CSB) Process Flow Diagram (PFD) and future reference. The attached mass balances were prepared to support revision two of the PFD for the CSB. The calculations refer to diagram H-2-825869.
Date: May 11, 2000
Creator: KLEM, M.J.
Object Type: Report
System: The UNT Digital Library
White paper updating conclusions of 1998 ILAW performance assessment (open access)

White paper updating conclusions of 1998 ILAW performance assessment

The purpose of this document is to provide a comparison of the estimated immobilized low-activity waste (LAW) disposal system performance against established performance objectives using the beat estimates for parameters and models to describe the system. The principal advances in knowledge since the last performance assessment (known as the 1998 ILAW PA [Mann 1998a]) have been in site specific information and data on the waste form performance for BNFL, Inc. relevant glass formulations. The white paper also estimates the maximum release rates for technetium and other key radionuclides and chemicals from the waste form. Finally, this white paper provides limited information on the impact of changes in waste form loading.
Date: May 11, 2000
Creator: Mann, F. M.
Object Type: Report
System: The UNT Digital Library
PLC and DTAM Software Programs for Pumping Instrumentation and Control Skid P (open access)

PLC and DTAM Software Programs for Pumping Instrumentation and Control Skid P

This document describe the software programs for the Programmable Logic Controller and the Datable Access Module for Pumping Instrumentation and Control skid ''P''. The Appendices contains copies of the printouts of these software programs.
Date: May 11, 2000
Creator: Koch, M. R.
Object Type: Report
System: The UNT Digital Library
Test Report for Acceptance Test Procedure for Pumping Instrumentation and Control Skid Q (open access)

Test Report for Acceptance Test Procedure for Pumping Instrumentation and Control Skid Q

This Acceptance Test Report (ATR) provides the test results for the inspection and testing of the new Pumping Instrumentation and Control (PIC) skid designed as ''Q''. The ATR summaries the results and provides a copy of the ATP and inspections in the Appendix.
Date: May 11, 2000
Creator: Koch, M. R.
Object Type: Report
System: The UNT Digital Library
HEPA Filter Vulnerability Assessment (open access)

HEPA Filter Vulnerability Assessment

This assessment of High Efficiency Particulate Air (HEPA) filter vulnerability was requested by the USDOE Office of River Protection (ORP) to satisfy a DOE-HQ directive to evaluate the effect of filter degradation on the facility authorization basis assumptions. Within the scope of this assessment are ventilation system HEPA filters that are classified as Safety-Class (SC) or Safety-Significant (SS) components that perform an accident mitigation function. The objective of the assessment is to verify whether HEPA filters that perform a safety function during an accident are likely to perform as intended to limit release of hazardous or radioactive materials, considering factors that could degrade the filters. Filter degradation factors considered include aging, wetting of filters, exposure to high temperature, exposure to corrosive or reactive chemicals, and exposure to radiation. Screening and evaluation criteria were developed by a site-wide group of HVAC engineers and HEPA filter experts from published empirical data. For River Protection Project (RPP) filters, the only degradation factor that exceeded the screening threshold was for filter aging. Subsequent evaluation of the effect of filter aging on the filter strength was conducted, and the results were compared with required performance to meet the conditions assumed in the RPP Authorization Basis …
Date: May 11, 2000
Creator: Gustavson, R. D.
Object Type: Report
System: The UNT Digital Library
HEPA Filter Differential Pressure Fan Interlock System Functional Requirements and Technical Design Criteria (open access)

HEPA Filter Differential Pressure Fan Interlock System Functional Requirements and Technical Design Criteria

Double-shell tanks (DSTs) and Double Contained Receiver Tanks (DCRTs) are actively ventilated, along with certain single-shell tanks (SSTs) and other RPP facilities. The exhaust air stream on a typical primary ventilation system is drawn through two stages of high-efficiency particulate air (HEPA) filtration to ensure confinement of airborne radioactive materials. Active ventilation exhaust stacks require a stack CAM interlock to detect releases from postulated accidents, and to shut down the exhaust fan when high radiation levels are detected in the stack airstream. The stack CAM interlock is credited as a mitigating control to stop continued unfiltered radiological and toxicological discharges from the stack, which may result from an accident involving failure of a HEPA filter. This document defines the initial technical design baseline for a HEPA filter AP fan interlock system.
Date: May 11, 2000
Creator: TUCK, J.A.
Object Type: Report
System: The UNT Digital Library
Tank 241-SY-102 January 2000 Compatibility Grab Samples Analytical Results for the Final Report [SEC 1 and 2] (open access)

Tank 241-SY-102 January 2000 Compatibility Grab Samples Analytical Results for the Final Report [SEC 1 and 2]

This document is the format IV, final report for the tank 241-SY-102 (SY-102) grab samples taken in January 2000 to address waste compatibility concerns. Chemical, radiochemical, and physical analyses on the tank SY-102 samples were performed as directed in Comparability Grab Sampling and Analysis Plan for Fiscal Year 2000 (Sasaki 1999). No notification limits were exceeded. Preliminary data on samples 2SY-99-5, -6, and -7 were reported in ''Format II Report on Tank 241-SY-102 Waste Compatibility Grab Samples Taken in January 2000'' (Lockrem 2000). The data presented here represent the final results.
Date: May 11, 2000
Creator: BELL, K.E.
Object Type: Report
System: The UNT Digital Library
Multi Canister Overpack (MCO) Topical Report [SEC 1 THRU 3] (open access)

Multi Canister Overpack (MCO) Topical Report [SEC 1 THRU 3]

In February 1995, the US Department of Energy (DOE) approved the Spent Nuclear Fuel (SNF) Project's ''Path Forward'' recommendation for resolution of the safety and environmental concerns associated with the deteriorating SNF stored in the Hanford Site's K Basins (Hansen 1995). The recommendation included an aggressive series of projects to design, construct, and operate systems and facilitates to permit the safe retrieval, packaging, transport, conditions, and interim storage of the K Basins' SNF. The facilities are the Cold VAcuum Drying Facility (CVDF) in the 100 K Area of the Hanford Site and the Canister Storage building (CSB) in the 200 East Area. The K Basins' SNF is to be cleaned, repackaged in multi-canister overpacks (MCOs), removed from the K Basins, and transported to the CVDF for initial drying. The MCOs would then be moved to the CSB and weld sealed (Loscoe 1996) for interim storage (about 40 years). One of the major tasks associated with the initial Path Forward activities is the development and maintenance of the safety documentation. In addition to meeting the construction needs for new structures, the safety documentation for each must be generated.
Date: May 11, 2000
Creator: LORENZ, B.D.
Object Type: Report
System: The UNT Digital Library
Engineering design of the National Spherical Torus Experiment (open access)

Engineering design of the National Spherical Torus Experiment

NSTX is a proof-of-principle experiment aimed at exploring the physics of the ``spherical torus'' (ST) configuration, which is predicted to exhibit more efficient magnetic confinement than conventional large aspect ratio tokamaks, amongst other advantages. The low aspect ratio (R/a, typically 1.2--2 in ST designs compared to 4--5 in conventional tokamaks) decreases the available cross sectional area through the center of the torus for toroidal and poloidal field coil conductors, vacuum vessel wall, plasma facing components, etc., thus increasing the need to deploy all components within the so-called ``center stack'' in the most efficient manner possible. Several unique design features have been developed for the NSTX center stack, and careful engineering of this region of the machine, utilizing materials up to their engineering allowables, has been key to meeting the desired objectives. The design and construction of the machine has been accomplished in a rapid and cost effective manner thanks to the availability of extensive facilities, a strong experience base from the TFTR era, and good cooperation between institutions.
Date: May 11, 2000
Creator: Neumeyer, C.; Heitzenroeder, P.; J. Spitzer, J. Chrzanowski & al, et
Object Type: Report
System: The UNT Digital Library
The wear-out approach for predicting the remaining lifetime of materials (open access)

The wear-out approach for predicting the remaining lifetime of materials

Failure models based on the Palmgren-Miner concept that material damage is cumulative have been derived and used mainly for fatigue life predictions for metals and composite materials. The authors review the principles underlying such models and suggest ways in which they may be best applied to polymeric materials in temperature environments. They first outline expectations when polymer degradation data can be rigorously time-temperature superposed over a given temperature range. For a step change in temperature after damage has occurred at an initial temperature in this range, the authors show that the remaining lifetime at the second temperature should be linearly related to the aging time prior to the step. This predicted linearity implies that it should be possible to estimate the remaining and therefore the service lifetime of polymers by completing the aging at an accelerated temperature. They refer to this generic temperature-step method as the Wear-out approach. They next outline the expectations for Wear-out experiments when time-temperature superposition is invalid. Experimental Wear-out results are then analyzed for one material where time-temperature superposition is valid and for another where evidence suggests it is invalid. In analyzing the data, they introduce a procedure that they refer to as time-degradation superposition. This …
Date: May 11, 2000
Creator: GILLEN,KENNETH T. & CELINA,MATHIAS C.
Object Type: Article
System: The UNT Digital Library
Numerical prediction of heat-flux to massive calorimeters engulfed in regulatory fires with the cask analysis fire environment (CAFE) model (open access)

Numerical prediction of heat-flux to massive calorimeters engulfed in regulatory fires with the cask analysis fire environment (CAFE) model

Recent observations show that the thermal boundary conditions within large-scale fires are significantly affected by the presence of thermally massive objects. These objects cool the soot and gas near their surfaces, and these effects reduce the incoming radiant heat-flux to values lower than the levels expected from simple {sigma}T{sub fire}{sup 4} models. They also affect the flow and temperature fields in the fire far from their surfaces. The Cask Analysis Fire Environment (CAFE) code has been developed at Sandia National Laboratories to provide an enhanced fire boundary condition for the design of radioactive material packages. CAFE is a set of computer subroutines that use computational fluid mechanics methods to predict convective heat transfer and mixing. It also includes models for fuel and oxygen transport, chemical reaction, and participating-media radiation heat transfer. This code uses two-dimensional computational models so that it has reasonably short turnaround times on standard workstations and is well suited for design and risk studies. In this paper, CAFE is coupled with a commercial finite-element program to model a large cylindrical calorimeter fully engulfed in a pool fire. The time-dependent heat-flux to the calorimeter and the calorimeter surface temperature are determined for several locations around the calorimeter circumference. …
Date: May 11, 2000
Creator: KOSKI,JORMAN A.; SUO-ANTITLA,AHTI; KRAMER,M. ALEX & GREINER,MILES
Object Type: Article
System: The UNT Digital Library
The unusual conduction band minimum formation of Ga(As{sub 0.5{minus}y}P{sub 0.5{minus}y}N{sub 2y}) alloys (open access)

The unusual conduction band minimum formation of Ga(As{sub 0.5{minus}y}P{sub 0.5{minus}y}N{sub 2y}) alloys

The conduction band minimum formation of GaAs{sub 0.5{minus}y}P{sub 0.5{minus}y}N{sub 2y} is investigated for small nitrogen compositions (0.1% < 2y < 1.0%), by using a pseudopotential technique. This formation is caused by two unusual processes both involving the deep-gap impurity level existing in the dilute alloy limit y {r_arrow} 0. The first process is an anticrossing with the {Gamma}{sub Ic}-like extended state of GaAs{sub 0.5}P{sub 0.5}. The second process is an interaction with other impurity levels forming a subband. These two processes are expected to occur in any alloys exhibiting a deep-gap impurity level at one of its dilute limit.
Date: May 11, 2000
Creator: Bellaiche, L.; Modine, Normand A. & Jones, Eric D.
Object Type: Article
System: The UNT Digital Library
Effective masses for small nitrogen concentrations in InGaAsN alloys on GaAs (open access)

Effective masses for small nitrogen concentrations in InGaAsN alloys on GaAs

The variation of the value of the linewidth of an excitonic transition in InGaAsN alloys (1% and 2% nitrogen) as a function of hydrostatic pressure using photoluminescence spectroscopy is studied at 4K. The excitonic linewidth increases as a function of pressure until about 100 kbar after which it tends to saturate. This pressure dependent excitonic linewidth is used to derive the pressure variation of the exciton reduced mass using a theoretical formalism based on the premise that the broadening of the excitonic transition is caused primarily by compositional fluctuations in a completely disordered alloy. The linewidth derived ambient pressure masses are compared and found to be in agreement with other mass measurements. The variation of this derived mass is compared with the results from a nearly first-principles approach in which calculations based on the local density approximation to the Kohn-Sham density functional theory are corrected using a small amount of experimental input.
Date: May 11, 2000
Creator: Jones, Eric D.; Allerman, Andrew A.; Kurtz, Steven R.; Fritz, Ian J.; Modine, Normand A.; Sieg, Robert M. et al.
Object Type: Article
System: The UNT Digital Library
Optical properties of spontaneous lateral composition modulations in AlAs/InAs short-period superlattices (open access)

Optical properties of spontaneous lateral composition modulations in AlAs/InAs short-period superlattices

The effect of lateral composition modulation, spontaneously generated during the epitaxial growth of a AlAs/InAs short-period superlattice, on the electronic band structure is investigated using photo-transmission and photoluminescence spectroscopy. Compared with uniform layers of similar average composition, the presence of the composition modulation considerably reduces the band gap energy and produces strongly polarized emission and absorption spectra. The authors demonstrate that the dominant polarization can selectively be aligned along the [{bar 1}10] or [010] crystallographic directions. In compressively strained samples, the use of (001) InP substrates slightly miscut toward [111]A or [101] resulted in modulation directions along [110] or [100], respectively, and dominant polarizations along a direction orthogonal to the respective composition modulation. Band gap reduction as high as 350 meV and 310 meV are obtained for samples with composition modulation along [110] and [100], respectively. Polarization ratios up to 26 are observed in transmission spectra.
Date: May 11, 2000
Creator: FRANCOEUR, S.; Alsina, F.; Zhang, Yong; Norman, A. G.; Mascarenhas, A.; Jones, Eric D. et al.
Object Type: Article
System: The UNT Digital Library
Patterned functional arrays by selective de-wetting (open access)

Patterned functional arrays by selective de-wetting

Using a micro-Contact Printing ({mu}-CP) technique, substrates are prepared with patterns of hydrophilic, hydroxyl-terminated SAMS and hydrophobic methyl-terminated SAMS. Beginning with a homogeneous solution of silica, surfactant, ethanol, water, and functional silane, preferential ethanol evaporation during dip-coating, causes water enrichment and selective de-wetting of the hydrophobic SAMS. Correspondingly, film deposition occurs exclusively on the patterned hydrophilic SAMS. In addition, by co-condensation of tetrafunctional silanes (Si(OR){sub 4}) with tri-functional organosilanes ((RO){sub 3}Si(CH{sub 2}){sub 3}NH{sub 2}), the authors have selectively derived the silica framework with functional amine NH{sub 2} groups. A pH sensitive, micro-fluidic system was formed by further conjugation reactions with pH sensitive dye molecules.
Date: May 11, 2000
Creator: Fan, Hongyou; Doshi, Dhaval; Lu, Yunfeng & Brinker, C. Jeffrey
Object Type: Article
System: The UNT Digital Library
Hanford Site climatological data summary 1999 with historical data (open access)

Hanford Site climatological data summary 1999 with historical data

This document presents the climatological data measured at the US Department of Energy's Hanford Site for calendar year 1999. Pacific Northwest National Laboratory operates the Hanford Meteorology Station and the Hanford Meteorological Monitoring Network from which these data were collected. The information contained herein includes updated historical climatologies for temperature, precipitation, normal and extreme values of temperature and precipitation, and other miscellaneous meteorological parameters. Further, the data are adjunct to and update Hoitink et al. (1999), and Hoitink and Burk (1994, 1995, 1996, 1997, 1998); however, Appendix B-Wind Climatology (1994) is excluded. 1999 was warmer than normal at the Hanford Meteorology Station with an average temperature of 54.4 F, 1.1 F above normal (53.3 F). The hottest temperature was 105 F on July 28, while the coldest was 18 F on January 3. The maximum temperature of 64 F on August 30 was the lowest maximum temperature ever recorded in August, while the maximum temperature of 76 F on November 13 was the highest maximum temperature ever recorded in November. For the 12-month period, 6 months were warmer than normal and 6 were cooler than normal. 1999 was the fourth driest year on record. Precipitation totaled 3.75 inches, 60% of …
Date: May 11, 2000
Creator: Hoitink, DJ; Burk, KW & Ramsdell, JV
Object Type: Report
System: The UNT Digital Library
In-plane magneto-photoluminescence studies of modulation-doped GaAs/AlGaAs coupled double quantum wells (open access)

In-plane magneto-photoluminescence studies of modulation-doped GaAs/AlGaAs coupled double quantum wells

In-plane magnetic field photoluminescence spectra from n series of n-type modulation doped GaAs/Al{sub 0.3}Ga{sub 0.7}As coupled double quantum wells show distinctive doublet structures related to the tunnel-split ground sub-level states. The magnetic field behavior of the upper transition from the antisymmetric state strongly depends on sample mobility. In a lower mobility sample, the transition energy displays an N-type kink with field (namely a maximum followed by a minimum), whereas higher mobility samples have a linear dependence. The former is attributed to a coupling mechanism due to homogeneous broadening of the electron and hole states. The results are in good agreement with recent theoretical calculations.
Date: May 11, 2000
Creator: KIM,YONGMIN; PERRY,C.H.; SIMMONS,JERRY A. & KLEM,JOHN F.
Object Type: Article
System: The UNT Digital Library