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Creators/Authors contains: "Bennett, R.G."
  1. Beginning in 1957 and continuing into the mid 1970s, the USSR conducted an extensive investigation into the use of both solid and gas core nuclear thermal rocket engines for space missions. During this time the scientific and engineering. problems associated with the development of a solid core engine were resolved. At the same time research was undertaken on a gas core engine, and some of the basic engineering problems associated with the concept were investigated. At the conclusion of the program, the basic principles of the solid core concept were established. However, a prototype solid core engine was not builtmore » because no established mission required such an engine. For the gas core concept, some of the basic physical processes involved were studied both theoretically and experimentally. However, no simple method of conducting proof-of-principle tests in a neutron flux was devised. This report focuses primarily on the development of the. gas core concept in the former USSR. A variety of gas core engine system parameters and designs are presented, along with a summary discussion of the basic physical principles and limitations involved in their design. The parallel development of the solid core concept is briefly described to provide an overall perspective of the magnitude of the nuclear thermal propulsion program and a technical comparison with the gas core concept.« less
  2. Beginning in 1957 and continuing into the mid 1970s, the USSR conducted an extensive investigation into the use of both solid and gas core nuclear thermal rocket engines for space missions. During this time the scientific and engineering. problems associated with the development of a solid core engine were resolved. At the same time research was undertaken on a gas core engine, and some of the basic engineering problems associated with the concept were investigated. At the conclusion of the program, the basic principles of the solid core concept were established. However, a prototype solid core engine was not builtmore » because no established mission required such an engine. For the gas core concept, some of the basic physical processes involved were studied both theoretically and experimentally. However, no simple method of conducting proof-of-principle tests in a neutron flux was devised. This report focuses primarily on the development of the. gas core concept in the former USSR. A variety of gas core engine system parameters and designs are presented, along with a summary discussion of the basic physical principles and limitations involved in their design. The parallel development of the solid core concept is briefly described to provide an overall perspective of the magnitude of the nuclear thermal propulsion program and a technical comparison with the gas core concept.« less
  3. A novel optical technique is described for the measurement of turbulently fluctuating temperature in a transparent fluid flow. The technique employs a Mach-Zehnder interferometer of extremely short field and a simple photoconductive diode detector. The system produces a nearly linear D.C. electrical analog of the turbulent temperature fluctuations in a small, 1 mm/sup 3/ volume. The frequency response extends well above 2500 Hz, and can be improved by the choice of a more sophisticated photodetector. The turbulent sodium mixing in the ANL 1/sup 1///sub 15/-scale FFTF outlet plenum is investigated with a scale model outlet mixing plenum, using flows ofmore » air. The scale design represents a cross section of the ANL outlet plenum, so that the average recirculating flow inside the test cell is two dimensional. The range of the instrument is 120/sup 0/F above the ambient air temperature. The accuracy is generally +-5/sup 0/F, with most of the error due to noise originating from building vibrations and room noise. The power spectral density of the fluctuating temperature has been observed experimentally at six different stations in the flow. A strong 300 Hz component is generated in the inlet region, which decays as the flow progresses along streamlines. The effect of the inlet Reynolds number and the temperature difference between the inlet flows on the power spectral density has also been investigated. Traces of the actual fluctuating temperature are included for the six stations.« less
  4. It has been common practice at petroleum refineries to dispose of oil sludges (containing oil, grease solids and water) in onsite pits. Remediation of these pits has typically involved in-situ solidification of the sludges using mixtures of Portland cement and fly ash. While this leaves the oily material in place, the resulting form is less permeable than the resulting sludge and has significant strength to support a cap. The supported cap reduces the infiltration rate of water to contact the solidified sludges. Due to the cumulative impact of the solidification and capping process the mobility of these materials is thereforemore » reduced. Since 1991 an oil refinery has been investigating the closure of several large storm water impoundment ponds. These ponds contain sediments that are high in oil and grease and mostly low in solids. Oil and grease content ranges from 1.5 to 20% by EPA Method 9071. Consistencies and liquid content of the sediments vary from a very wet free flowing emulsion to a congealed sludge with about 70% solids. The primary concern of closure was to solidify the residues while still maintaining the low leachability and mobility of both metals and volatile organic hydrocarbons (VOCs).« less
  5. A multi-part treatability study was conducted to identify lower cost solidification reagents for the solidification of oily sediments from several storm sewer impoundment ponds. The information from the treatability study was successfully applied to full-scale remediation. Several reagents were investigated including Portland cement, Class C fly ash, lime, cement kiln dust, and fluidized bed combustor ash. Screening tests were performed using single reagents and blended mixes of reagents. Testing included strength development, permeability, oil retention and volume increase due to treatment. The applicability of using the fluidized bed combustor ash was tested in a full scale field pilot study priormore » to full scale remediation. This paper will present background and experimental data from this study showing the successful substitution of fluidized bed combustor ash for cement as a primary solidification reagent.« less
  6. The Idaho National Engineering Laboratory is performing research and development of a cross-flow, internal-reforming SOFC. Part of the effort entails development of a thermo-chemical computer model to execute scoping, design, and performance studies of the INTEL SOFC design. A one-dimensional model is being completed and extensions to two and three-dimensions are planned. Mass, heat, electrochemical, and chemical kinetic balance equations are presented along with preliminary simulation results.
  7. Technetium-99m is the radioisotope of choice for >80% of all nuclear medical imaging procedures today in the United States. There are > 12 million {sup 99m}Tc scans performed in the United States per year. Since the development of fission-based radio nuclide generators for {sup 99}Mo, {sup 99m}Tc use has grown steadily over the past 20 yr. Despite the widespread demand for {sup 99m}Tc in medicine, a reliable and assured supply of the parent, {sup 99}Mo, does not exist. Construction of Maple-1 and -2, two new Canadian isotope production reactors intended to replace the aging National Research Universal (NRU) reactor, hasmore » been approved in an agreement among Atomic Energy of Canada Limited, MDS Nordion, and the Canadian government. However, the project is expensive: The anticipated cost of Maple-1 and -2 is $C140 million. Outlays toward this cost have recently driven the price of {sup 99}Mo up by 40%, even though the Canadian {sup 99}Mo production will continue to be heavily subsidized by an interest-free construction loan. Research and development for an accelerator-based facility has been undertaken and is described.« less
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