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Analysis of heat transfer during quenching of a gear blank
This paper presents experimental and numerical results for the quench of a gear blank in agitated and stagnant oil. Heat transfer within the gear blank is analyzed with a whole domain-optimizer technique inverse solution method, to calculate the time history at every point in the gear blank. The development of this procedure represents the first stage in an overall analysis of the quench process that will later include material phase transformations and deformation. The paper presents ten variations in setting up the inverse problem, to analyze which combination of independent variables and decision variables results in the best match between experimental and numerical results. The results indicate that dividing the boundary of the gear blank into four zones and assigning a fixed heat transfer coefficient or heat flux to each zone yields an average RMS error (average difference between experimental and numerical results) of the order of 40 K. This error can be reduced by either increasing the number of zones, by reducing the number of thermocouples being matched, or by allowing the heat transfer or heat flux to vary within the zones. Of these possibilities, variation of heat transfer within the zones gives the best improvement in the quality …
Date:
March 1, 1999
Creator:
Aceves, S M & Sahai, V
Object Type:
Article
System:
The UNT Digital Library
Evaluation of insulated pressure vessels for cryogenic hydrogen storage
This paper presents an analytical and experimental evaluation of the applicability of insulated pressure vessels for hydrogen-fueled light-duty vehicles. Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH?) or ambient-temperature compressed hydrogen (CH2). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The purpose of this work is to verify that commercially available aluminum-lined, fiber- wrapped vessels can be used for cryogenic hydrogen storage. The paper reports on previous and ongoing tests and analyses that have the purpose of improving the system design and assure its safety.
Date:
March 1, 1999
Creator:
Aceves, S M; Garcia-Villazana, O & Martinez-Frias, J
Object Type:
Article
System:
The UNT Digital Library
An Accuracy Evaluation for the Madejski Splat-Quench Solidification Model
Development of methods to spray form materials by precisely controlled deposition of droplets can result in new manufacturing processes which offer improved metallurgical performance and reduced production costs. These processes require a more detailed knowledge of the fluid mechanics, heat transfer and solidification that occur during droplet spreading. Previous work using computer simulations of this process have been difficult to implement and have required long running times. This paper examines the use of an alternative, simplified, method developed by Madjeski for solving for the problem of droplet spreading and solidification. These simplifications reduce the overall splat spreading and solidification problem to a closed-form differential equation. This differential equation is then solved under various conditions as reported from recent publications of experimental and numerical results of drop analysis. The results from the model are compared in terms of maximum spl at diameter, minimum splat thickness, and time for the droplet spreading to reach 95% of the maximum diameter. The results indicate that the accuracy of the model can be improved by accounting for energy losses in the initial rate of droplet spreading. The model results show that the predictions of experimental results are improved to within 30% over a wide range …
Date:
March 1, 1999
Creator:
Aceves, S. M.; Sahai, V. & Shapiro, A. B.
Object Type:
Article
System:
The UNT Digital Library
Sensitivity of natural gas HCCI combustion to fuel and operating parameters using detailed kinetic modeling
This paper uses the HCT (Hydrodynamics, Chemistry and Transport) chemical kinetics code to analyze natural gas HCCI combustion in an engine. The HCT code has been modified to better represent the conditions existing inside an engine, including a wall heat transfer correlation. Combustion control and low power output per displacement remain as two of the biggest challenges to obtaining satisfactory performance out of an HCCI engine, and these are addressed in this paper. The paper considers the effect of natural gas composition on HCCI combustion, and then explores three control strategies for HCCI engines: DME (dimethyl ether) addition, intake heating and hot EGR addition. The results show that HCCI combustion is sensitive to natural gas composition, and an active control may be required to compensate for possible changes in composition. The three control strategies being considered have a significant effect in changing the combustion parameters for the engine, and should be able to control HCCI combustion.
Date:
July 19, 1999
Creator:
Aceves, S.; Dibble, R.; Flowers, D.; Smith, J. R. & Westbrook, C. K.
Object Type:
Article
System:
The UNT Digital Library
High Precision Droplet Based New Form Manufacturing
In collaboration with the University of California at Irvine (UCI), we are working on a new technology that relies on the precise deposition of nanoliter molten-metal droplets that are targeted onto a substrate by electrostatic charging and deflection. By this way, three-dimensional (3D) structural materials can be manufactured microlayer by microlayer. Because the volume of the droplets are small, they rapidly solidify on impact, bringing forth a material component with fine grain structures which lead to enhanced material properties (e.g., strength). UCI is responsible for an experimental investigation of the manufacturing feasibility of this process. LLNL has unique expertise in the computational modeling of 3D heat transfer and solid mechanics and has the large-scale computer resources necessary to model this large system. Process modeling will help move this technology from the bench-top to an industrial process. Applications at LLNL include rapid prototyping of metal parts and manufacturing new alloys by co-jetting different metals.
Date:
September 16, 1999
Creator:
Aceves, S.; Hadjiconstantinou, N.; Miller, W. O.; Orme, M.; Sahai, V. & Shapiro, A. B.
Object Type:
Report
System:
The UNT Digital Library
Kosovo and NATO: Selected Issues of International Law
None
Date:
April 28, 1999
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
1998 Chemical Technology Division Annual Technical Report.
The Chemical Technology (CMT) Division is a diverse technical organization with principal emphases in environmental management and development of advanced energy sources. The Division conducts research and development in three general areas: (1) development of advanced power sources for stationary and transportation applications and for consumer electronics, (2) management of high-level and low-level nuclear wastes and hazardous wastes, and (3) electrometallurgical treatment of spent nuclear fuel. The Division also performs basic research in catalytic chemistry involving molecular energy resources, mechanisms of ion transport in lithium battery electrolytes, and the chemistry of technology-relevant materials. In addition, the Division operates the Analytical Chemistry Laboratory, which conducts research in analytical chemistry and provides analytical services for programs at Argonne National Laboratory (ANL) and other organizations. Technical highlights of the Division's activities during 1998 are presented.
Date:
August 6, 1999
Creator:
Ackerman, J. P.; Einziger, R. E.; Gay, E. C.; Green, D. W. & Miller, J. F.
Object Type:
Report
System:
The UNT Digital Library
A new mechanical characterization method for microactuators applied to shape memory films
We present a new technique for the mechanical characterization of microactuators and apply it to shape memory alloy (SMA) thin films. A test instrument was designed which utilizes a spring-loaded transducer to measure displacements with resolution of 1.5 mm and forces with resolution of 0.2 mN. Employing an out- of-plane loading method for SMA thin films, strain resolution of 30 me and stress resolution of 2.5 MPa were achieved. Four mm long, 2 {micro}m thick NiTiCu ligaments suspended across open windows were bulk micromachined for use in the out-of-plane stress and strain measurements. Static analysis showed that 63% of the applied strain was recovered while ligaments were subjected to tensile stresses of 870 MPa. This corresponds to 280 mm of actual displacement against a load of 52 mN. Fatigue analysis of the ligaments showed 33% degradation in recoverable strain (from 0.3% to 0.2%) with 2 {+-} 10{sup 4} cycles for an initial strain of 2.8%.
Date:
March 1, 1999
Creator:
Ackler, H D; Krulevitch, P; Ramsey, P B & Seward, K P
Object Type:
Article
System:
The UNT Digital Library
Effects of Particulate Debris Morphology on the Rolling Wear Behavior of All-Steel and Si(Sub 3)N(Sub 4)-Steel Bearing Element Couples
Rolling contact fatigue experiments were performed on all-steel and hybrid Si{sub 3}N{sub 4}-M50 steel rolling bearing systems using particulate contaminated lubricants. The particulate contaminants used were glycothermally synthesized {alpha}-Al{sub 2}O{sub 3} platelets or Arizona test dust. The effects of contaminant composition and morphology on rolling contact fatigue and wear behavior were explored. The effects of bearing element material properties on fatigue and wear behavior were also examined. Rolling wear behavior is related to bearing component material configuration and the type of particulate contaminant present in the lubricant. Component and particulate material properties such as hardness and elastic modulus are observed to affect rolling wear behavior. Wear mechanisms such as contact stress fatigue, indenting, cutting and plowing are observed.
Date:
January 25, 1999
Creator:
Adair, J.H.; Mecholsky, J.J., Jr. & Mitchell, D.J.
Object Type:
Article
System:
The UNT Digital Library
Orientation imaging microscopy investigation of the compression deformation of a [011] ta single crystal
High-purity tantalum single crystal cylinders oriented with [110] parallel to the cylinder axis were deformed 10, 20, and 30 percent in compression. The samples were subsequently sectioned for characterization using Orientation Imaging Microscopy (O&I) along two orthogonal sectioning planes: one in the plane containing [001] and [110] (longitudinal) and the other in the plane containing [1{anti 1}0] and[110] (transverse). To examine local lattice rotations, the Euler angles relative to a reference angle at the section center were decomposed to their in-plane and out-of-plane components. The in-plane and out-of-plane misorientation maps for all compression tests reveal inhomogeneous deformation everywhere and particularly large lattice rotations in the comers of the longitudinal section. Of particular interest are the observed alternating orientation changes. This suggests the existence of networks of dislocations with net alternating sign that are required to accommodate the observed rotations. Rotation maps from the transverse section are distinctly different in appearance from those in the longitudinal plane. However, the rotation maps confirm that the rotations observed above were about the [1{anti 1}0] axis. Alternating orientation changes are also observed on this section. Results will be directly compared with crystal rotations predicted using finite element methods and reviewed in light of the …
Date:
January 8, 1999
Creator:
Adams, B L; Campbell, G H; King, W E; Lassila, D H; Stolken, J S; Sun, S et al.
Object Type:
Report
System:
The UNT Digital Library
Analysis of compression behavior of a [011] Ta single crystal with orientation imaging microscopy and crystal plasticity
High-purity tantalum single crystal cylinders oriented with [011] parallel to the cylinder axis were deformed 10, 20, and 30 percent in compression. The engineering stress-strain curve exhibited an up-turn at strains greater than {approximately}20% while the samples took on an ellipsoidal shape during testing, elongated along the [100] direction with almost no dimensional change along [0{bar 1}1]. Two orthogonal planes were selected for characterization using Orientation Imaging Microscopy (OIM): one plane containing [100] and [011] (longitudinal) and the other in the plane containing [0{bar 1}1] and [011] (transverse). OIM revealed patterns of alternating crystal rotations that develop as a function of strain and exhibit evolving length scales. The spacing and magnitude of these alternating misorientations increases in number density and decreases in spacing with increasing strain. Classical crystal plasticity calculations were performed to simulate the effects of compression deformation with and without the presence of friction. The calculated stress-strain response, local lattice reorientations, and specimen shape are compared with experiment.
Date:
February 3, 1999
Creator:
Adams, B. L.; Campbell, G. H.; King, W. E.; Lassila, D. H.; Stolken, J. S.; Sun, S. et al.
Object Type:
Article
System:
The UNT Digital Library
Scanning Probe-Based Processes for Nanometer-Scale Device Fabrication
This is the final report of an LDRD program entitled 'Scanning Probe-Based Processes for Nanometer-Scale Device Fabrication'. This program intends to expand Sandia's expertise in scanning-probe based fabrication and characterization of nanostructures. Our object is to achieve an order of magnitude decrease in feature size compared to conventional fabrication technology. We are exploring approaches to nanostructure fabrication and characterization using scanning probe-based (STM, AFM). We also are developing numerical simulations of localized electric field and emission current to explore mechanisms and characterize limits to processing techniques. We emphasize novel fabrication processes and characterization of physical, chemical and electronic effects in nanostructures.
Date:
January 1, 1999
Creator:
Adams, D. P.; Houston, J. D.; Mayer, T. M. & Swartzentruber, B. S.
Object Type:
Report
System:
The UNT Digital Library
Tunable laser action at 4.0 microns from Fe:ZnSe
None
Date:
January 29, 1999
Creator:
Adams, J. J.; Page, R. H.; Bibeau, C. & Payne, S. A.
Object Type:
Article
System:
The UNT Digital Library
National Low-Level Waste Management Program Radionuclide Report Series, Volume 17: Plutonium-239
This report, Volume 17 of the National Low-Level Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of plutonium-239 (Pu-239). This report also discusses waste types and forms in which Pu-239 can be found, waste and disposal information on Pu-239, and Pu-239 behavior in the environment and in the human body.
Date:
March 1, 1999
Creator:
Adams, J. P. & Carboneau, M. L.
Object Type:
Report
System:
The UNT Digital Library
Sepradyne/Raduce High Vacuum Thermal Process for Destruction of Dioxins in Ineel/Werf Fly Ash.
This study investigated the use of an indirectly heated, high temperature (900 C), high vacuum (28 inch Hg) rotary kiln, developed and patented by Raduce, Inc. (subsidiary of Sepradyne Corp.), to treat a dioxin contaminated mixed waste incinerator ash from the Idaho National Engineering Lab (INEEL) Waste Experimental Reduction Facility (WERF). A 500 cm{sup 3} bench-scale rotary vacuum thermal desorption and destruction unit (DDU) was used at Brookhaven National Laboratory (BNL) to demonstrate this thermal treatment process. Dioxins and furans were successfully decomposed at both low (450 C) and high (700-800 C) temperature regimes. In addition, substantial volume and mass reduction of the ash was achieved. Stabilization of the nonvolatile residues by a post-treatment encapsulation process may be required to reduce the leachability of RCRA metals to levels below the EPA Toxicity Characteristic Leaching Procedure (TCLP) requirements.
Date:
August 2, 1999
Creator:
Adams, J. W.; Kalb, P. D. & Malkmus, D. B.
Object Type:
Report
System:
The UNT Digital Library
Sepradyne/Reduce High Vacuum Thermal Process for Destruction of Dioxins in Ineel/Werf Fly Ash.
This study investigated the use of an indirectly heated, high temperature (900 C), high vacuum (28'' Hg) rotary kiln, developed and patented by Raduce, Inc. (subsidiary of Sepradyne Corp.), to treat a dioxin contaminated mixed waste incinerator ash from the Idaho National Engineering Lab (INEEL) Waste Experimental Reduction Facility (WERF). A 500 cm{sup 3} bench-scale rotary vacuum thermal desorption and destruction unit (DDU) was used at Brookhaven National Laboratory (BNL) to demonstrate this thermal treatment process. Dioxins and furans were successfully decomposed at both low (450 C) and high (700-800 C) temperature regimes. In addition, substantial volume and mass reduction of the ash was achieved. Stabilization of the nonvolatile residues by a post-treatment encapsulation process may be required to reduce the leachability of RCRA metals to levels below the EPA Toxicity Characteristic Leaching Procedure (TCLP) requirements.
Date:
August 2, 1999
Creator:
Adams, J. W.; Kalb, P. D. & Malkmus, D. B.
Object Type:
Report
System:
The UNT Digital Library
National Low-Level Waste Management Program Radionuclide Report Series
The National Low Level Waste Management Program at the Idaho National Engineering and Environmental Laboratory has published a report containing key information about selected radionuclides that are most likely to contribute significantly to the radiation exposures estimated from a performance assessment of a low-level radioactive waste (LLW) disposal facility. The information includes physical and chemical characteristics, production means, waste forms, behavior of the radionuclide in soils, plants, groundwater, and air, and biological effects in animals and humans. The radionuclides included in this study comprise all of the nuclides specifically listed in 10CFR61.55, Tables 1 and 2, 3 H, 14 C, 59 Ni, 60 Co, 63 Ni, 90 Sr, 94 Nb, 99 Tc, 129 I, 137 Cs, 241 Pu, and 242 Cm. Other key radionuclides addressed in the report include 237 Np, 238 U, 239 Pu, and 241 Am. This paper summarizes key information contained within this report.
Date:
February 1, 1999
Creator:
Adams, J.P.; Carboneau, M.L. & Allred, W.E.
Object Type:
Article
System:
The UNT Digital Library
National Low-Level Waste Management Program Radionuclide Report Series
The National Low Level Waste Management Program at the Idaho National Engineering and Environmental Laboratory has published a report containing key information about selected radionuclides that are most likely to contribute significantly to the radiation exposures estimated from a performance assessment of a low-level radioactive waste (LLW) disposal facility. The information includes physical and chemical characteristics, production means, waste forms, behavior of the radionuclide in soils, plants, groundwater, and air, and biological effects in animals and humans. The radionuclides included in this study comprise all of the nuclides specifically listed in 10CFR61.55, Tables 1 and 2, 3 H, 14 C, 59 Ni, 60 Co, 63 Ni, 90 Sr, 94 Nb, 99 Tc, 129 I, 137 Cs, 241 Pu, and 242 Cm. Other key radionuclides addressed in the report include 237 Np, 238 U, 239 Pu, and 241 Am. This paper summarizes key information contained within this report.
Date:
March 1, 1999
Creator:
Adams, James Paul; Carboneau, Michael Leonard & Allred, William Edgar
Object Type:
Article
System:
The UNT Digital Library
LMHC/TWRS year 2000 equipment project renovation and contingency plan
A program has been completed to assess, renovate and document tank farm field equipment year 2000 compliance. A communication plan has also been prepared (see section 8.0). The objective of the program was to assure that no adverse effects occur in tank farm operations as a result of equipment malfunction due to the advent of year 2000. The purposes of this document are to: describe the process used to assess field equipment; document items found to be compliant; document items found to be non-compliant including options for making the equipment year 2000 functional and/or tolerant; describe location and management of field equipment year 2000 documentation; assess overall vulnerability of TWRS field equipment with regard to year 2000 problems and describe plans to communicate year 2000 equipment review results and corrective actions.
Date:
May 12, 1999
Creator:
Adams, M. R.
Object Type:
Report
System:
The UNT Digital Library
Protocol for disposition of tank farm equipment lists and tank farm drawings for year 2000 compliance
A program has been initiated to assess, renovate, document and certify tank farm field equipment for year 2000 compliance. The program is necessary to assure no adverse effects occur in tank farm operations as a result of equipment malfunction due to what is widely known as the ''millennium bug''. This document elaborates the protocols for reviewing field equipment lists and tank farm drawings for the purpose of identifying and resolving year 2000 compliance problems in tank farm equipment.
Date:
February 23, 1999
Creator:
Adams, M. R.
Object Type:
Report
System:
The UNT Digital Library
Standard Electronic Format Specification for Tank Characterization Data Loader Version 3.0
The purpose of this document is to describe the standard electronic format for data files that will be sent for entry into the Tank Characterization Database (TCD). There are 2 different file types needed for each data load: Analytical Results; and Sample Descriptions. The first record of each file must be a header record. The content of the first 5 fields is ignored. They were used previously to satisfy historic requirements that are no longer applicable. The sixth field of the header record must contain the Standard Electronic Format (SEF) version ID (SEF3.0). The remaining records will be formatted as specified below. Fields within a record will be separated using the ''|'' symbol. The ''|''symbol must not appear anywhere in the file except when used as a delimiter.
Date:
August 12, 1999
Creator:
Adams, M. R.
Object Type:
Report
System:
The UNT Digital Library
Year 2000 TWRS Maintenance procedure review report
A concern exists that some equipment in use might contain microprocessors that are dependent upon a time date function. The majority of the software programming for microprocessors has only utilized a 2 digit identifier for the year. With the approach of the year 2000, (Y2K), there is concern that the date function will not be correctly recognized and some functions will not operate properly. TWRS maintenance procedures have been reviewed to identify equipment components that may not be Y2K compliant. Engineering judgment was utilized to eliminate procedures and equipment that is obviously not impacted by Y2K.
Date:
February 24, 1999
Creator:
Adams, M. R.
Object Type:
Report
System:
The UNT Digital Library
Studies of Flexible MOX/LEU Fuel Cycles
This project was a collaborative effort involving researchers from Oak Ridge National Laboratory and North Carolina State University as well as Texas A and M University. The background, briefly, is that the US is planning to use some of its excess weapons Plutonium (Pu) to make mixed-oxide (MOX) fuel for existing light-water reactors (LWRs). Considerable effort has already gone into designing fuel assemblies and core loading patterns for the transition from full-uranium cores to partial-MOX and full-MOX cores. However, these designs have assumed that any time a reactor needs MOX assemblies, these assemblies will be supplied. In reality there are many possible scenarios under which this supply could be disrupted. It therefore seems prudent to verify that a reactor-based Pu-disposition program could tolerate such interruptions in an acceptable manner. Such verification was the overall aim of this project. The task assigned to the Texas A and M team was to use the HELIOS code to develop libraries of two-group homogenized cross sections for the various assembly designs that might be used in a Westinghouse Pressurized Water Reactor (PWR) that is burning weapons-grade MOX fuel. The NCSU team used these cross sections to develop optimized loading patterns under several assumed scenarios. …
Date:
March 1, 1999
Creator:
Adams, M.L. & Alonso-Vargas, G.
Object Type:
Report
System:
The UNT Digital Library
Bin Set 1 Calcine Retrieval Feasibility Study
At the Department of Energy's Idaho Nuclear Technology and Engineering Center, as an interim waste management measure, both mixed high-level liquid waste and sodium bearing waste have been solidified by a calculation process and are stored in the Calcine Solids Storage Facilities. This calcined product will eventually be treated to allow final disposal in a national geologic repository. The Calcine Solids Storage Facilities comprise seven ''bit sets.'' Bin Set 1, the first to be constructed, was completed in 1959, and has been in service since 1963. It is the only bin set that does not meet current safe-shutdown earthquake seismic criteria. In addition, it is the only bin set that lacks built-in features to aid in calcine retrieval. One option to alleviate the seismic compliance issue is to transport the calcine from Bin Set 1 to another bin set which has the required capacity and which is seismically qualified. This report studies the feasibility of retrieving the calcine from Bi n Set 1 and transporting it into Bin Set 6 which is located approximately 650 feet away. Because Bin Set 1 was not designed for calcine retrieval, and because of the high radiation levels and potential contamination spread from the …
Date:
October 1, 1999
Creator:
Adams, R. D.; Berry, S. M.; Galloway, K. J.; Langenwalter, T. A.; Lopez, D. A.; Noakes, C. M. et al.
Object Type:
Report
System:
The UNT Digital Library