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New multigroup Monte Carlo scattering algorithm suitable for neutral- and charged-particle Boltzmann and Fokker-Planck calculations

Description: Morel (1981) has developed multigroup Legendre cross sections suitable for input to standard discrete ordinates transport codes for performing charged-particle Fokker-Planck calculations in one-dimensional slab and spherical geometries. Since the Monte Carlo neutron transport code, MORSE, uses the same multigroup cross section data that discrete ordinates codes use, it was natural to consider whether Fokker-Planck calculations could be performed with MORSE. In order to extend the unique three-dimensional forward or adjoint capability of MORSE to Fokker-Planck calculations, the MORSE code was modified to correctly treat the delta-function scattering of the energy operator, and a new set of physically acceptable cross sections was derived to model the angular operator. Morel (1979) has also developed multigroup Legendre cross sections suitable for input to standard discrete ordinates codes for performing electron Boltzmann calculations. These electron cross sections may be treated in MORSE with the same methods developed to treat the Fokker-Planck cross sections. The large magnitude of the elastic scattering cross section, however, severely increases the computation or run time. It is well-known that approximate elastic cross sections are easily obtained by applying the extended transport (or delta function) correction to the Legendre coefficients of the exact cross section. An exact method for performing the extended transport cross section correction produces cross sections which are physically acceptable. Sample calculations using electron cross sections have demonstrated this new technique to be very effective in decreasing the large magnitude of the cross sections.
Date: May 1, 1983
Creator: Sloan, D.P.
Partner: UNT Libraries Government Documents Department

Net-energy analysis of a retrofit geothermal-heating system

Description: A net energy analysis was carried out as part of a study of the potential engineering and economic feasibility for geothermal heating of the campus of the University of New Mexico in Albuquerque. The geothermal system design included production and disposal wells, surface facilities and retrofitting of eighteen existing buildings. For a 30-year project life, the net energy ratio was found to be about 7.1.
Date: January 1, 1981
Creator: Kauffman, D.; Houghton, A.V. & Kuo, W.S.
Partner: UNT Libraries Government Documents Department

Engineering and economic evaluation of direct hot-water geothermal energy applications on the University of New Mexico campus. Final technical report

Description: The potential engineering and economic feasibility of low-temperature geothermal energy applications on the campus of the University of New Mexico is studied in detail. This report includes three phases of work: data acquisition and evaluation, system synthesis, and system refinement and implementation. Detailed process designs are presented for a system using 190/sup 0/F geothermal water to substitute for the use of 135 x 10/sup 9/ Btu/y (141 TJ/y) of fossil fuels to provide space and domestic hot water heating for approximately 23% of the campus. Specific areas covered in the report include economic evaluation, environmental impact and program implementation plans.
Date: December 31, 1980
Creator: Kauffman, D. & Houghton, A.V.
Partner: UNT Libraries Government Documents Department

Workshop on geologic data requirements for radioactive waste management assessment models, Santa Fe, New Mexico, June 28--July 1, 1976

Description: Exchange of information is needed among persons working in two broad categories of studies concerned with terminal storage of radioactive waste. These two categories are: (1) investigations of several types of geologic formations in a number of locations to determine suitability for use with various emplacement techniques, and (2) development of models for the ERDA, NRC, and EPA, for the general purpose of assessing the long term safety of terminal storage facilities. The Workshop held in Santa Fe, New Mexico, June 28-July 1, 1976, sponsored by the Office of Waste Isolation and arranged by The University of New Mexico addressed this need. Presentations covered background topics of: geologic studies being made, methods for risk analysis, assessment models being developed, and descriptions of field observations of radionuclide migration. During vigorous discussion periods, a list of items to be jointly attacked by geologists and modelers was worked out.
Date: September 1, 1976
Partner: UNT Libraries Government Documents Department

Benefit-cost framework for analysis of trace element emissions from coal-fired power plants. [103 references]

Description: The major conclusions of this report may be summarized in the following four points: (1) It is probable that atmospheric emissions of trace elements from Southwestern coal-fired power plants will not cause major problems over the next 20 years. But monitoring for trace element build-up (especially mercury, selenium, and arsenic) in the mountains of southern Colorado, Navajo Reservoir, and other local hot spots would be an important and desirable step. (2) It appears that damage from trace elements in disposed ash is more likely than damage from atmospheric trace element emissions. But whether damage from disposed ash will actually occur is highly uncertain. We recommend that additional research be conducted on the entire range of issues surrounding ash disposal. (3) In the area of legislation and regulation, there may be some need for review of regulations concerning trace element atmospheric emissions. Present regulation of ash disposal is very likely to need revision and extension. (4) Future research on the environmental problems of coal-fired power plants should place emphasis on atmospheric emissions of sulfur and nitrogen oxides; consequent problems of acid precipitation also need exploration. Environmental research on coal-fired power plants does not need to exclude other problems. But issues surrounding sulfur emissions, nitrogen emissions, sulfate transformations, and acid precipitation appear to merit major emphasis. Perhaps the most important aspect of the preceding list of conclusions is that more questions are raised than are answered. As work on the subject proceeded, it became apparent that an important task was to point future research in the right direction.
Date: November 1, 1979
Partner: UNT Libraries Government Documents Department

Photoassisted electrolysis applied to coal gasification. Third quarterly report, 1 January 1982-31 Mar 1982

Description: The literature search on electrochemical studies of various carbons has been completed. Two conclusions were reached: (1) The surfaces of various carbons are covered by oxide films to different extents and the oxides resemble either the quinone-like structure in their oxidized form or the hydroquinone-like structure in the reduced form. (2) When carbonaceous materials are oxidized chemically, electrochemically, or thermally, the first stage involves formation of the oxide film and the later stages oxide gas (CO or CO/sub 2/) evolution. The catalytic reaction mechanism of coal oxidation was substantiated by adding Fe/sup 3 +/ or Ce/sup 4 +/ to a cell containing a coal slurry without passing any electrical current and by monitoring the amount of CO/sub 2/ evolved. Also, studies were performed on current efficiencies of CO/sub 2/ production reaction as a function of the particle size of coal samples. Finally, the catalytic rate constants of various redox catalysts for the coal oxidation reaction are reported. These results indicate that the thermodynamics of the reaction systems play a predominant role in determining the rate constants. Methods of studying the stability of semiconductor electrodes were established employing rotating ring-disk electrode techniques. The long-term stability of semiconductor electrodes would be needed to carry out the photoassisted coal gasification reaction. In the method we developed, the semiconductor was used as a disk electrode while the noble metal, e.g., Au or Pt, is used as a ring electrode. The species generated at the semiconductor electrode by light illumination is detected at the ring electrode by applying the proper electrode potential. If the ring detection current is lower than its expected value, the disk may undergo the photocorrosion reaction.
Date: January 1, 1982
Partner: UNT Libraries Government Documents Department

Uranium deposits of the Grants, New Mexico mineral belt (II). [Genesis]

Description: This is part of a study of the genesis of the U deposits of the Grants mineral belt. Enrichment of Mg in ore zones is frequently observed, with chlorite being a common product. Clay mineralogic studies argue for chlorite-illite-montmorillonite associations with ores. The methods include scanning electron microscopy, Eh-pH diagrams, activation analysis, and rare earth element studies. (DLC)
Date: July 1, 1979
Creator: Brookins, D.G.
Partner: UNT Libraries Government Documents Department

Economic modeling of electricity production from hot dry rock geothermal reservoirs: methodology and analyses. Final report

Description: An analytical methodology is developed for assessing alternative modes of generating electricity from hot dry rock (HDR) geothermal energy sources. The methodology is used in sensitivity analyses to explore relative system economics. The methodology used a computerized, intertemporal optimization model to determine the profit-maximizing design and management of a unified HDR electric power plant with a given set of geologic, engineering, and financial conditions. By iterating this model on price, a levelized busbar cost of electricity is established. By varying the conditions of development, the sensitivity of both optimal management and busbar cost to these conditions are explored. A plausible set of reference case parameters is established at the outset of the sensitivity analyses. This reference case links a multiple-fracture reservoir system to an organic, binary-fluid conversion cycle. A levelized busbar cost of 43.2 mills/kWh ($1978) was determined for the reference case, which had an assumed geothermal gradient of 40/sup 0/C/km, a design well-flow rate of 75 kg/s, an effective heat transfer area per pair of wells of 1.7 x 10/sup 6/ m/sup 2/, and plant design temperature of 160/sup 0/C. Variations in the presumed geothermal gradient, size of the reservoir, drilling costs, real rates of return, and other system parameters yield minimum busbar costs between -40% and +76% of the reference case busbar cost.
Date: September 1, 1979
Creator: Cummings, R.G. & Morris, G.E.
Partner: UNT Libraries Government Documents Department

Evaluation of geothermal potential of Rio Grande rift and Basin and Range province, New Mexico. Final technical report, January 1, 1977-May 31, 1978

Description: A study was made of the geological, geochemical and geophysical characteristics of potential geothermal areas in the Rio Grande rift and Basin and Range province of New Mexico. Both regional and site-specific information is presented. Data was collected by: (1) reconnaissance and detailed geologic mapping, emphasizing Neogene stratigraphy and structure; (2) petrologic studies of Neogene igneous rocks; (3) radiometric age-dating; (4) geochemical surveying, including regional and site-specific water chemistry, stable isotopic analyses of thermal waters, whole-rock and mineral isotopic studies, and whole-rock chemical analyses; and (5) detailed geophysical surveys, using electrical, gravity and magnetic techniques, with electrical resistivity playing a major role. Regional geochemical water studies were conducted for the whole state. Integrated site-specific studies included the Animas Valley, Las Cruces area (Radium Springs and Las Alturas Estates), Truth or Consequences region, the Albuquerque basin, the San Ysidro area, and the Abiquiu-Ojo Caliente region. The Animas Valley and Las Cruces areas have the most significant geothermal potential of the areas studied. The Truth or Consequences and Albuquerque areas need further study. The San Ysidro and Abiquiu-Ojo Caliente regions have less significant geothermal potential. 78 figs., 16 tabs.
Date: April 1, 1985
Creator: Callender, J.F.
Partner: UNT Libraries Government Documents Department

Evaluation of the geothermal resource in the area of Albuquerque, New Mexico

Description: Factors indicating a potential geothermal resource near Albuquerque are: (1) nearby volcanoes active as recently as 120,000 years ago, (2) gravity interpretation indicating a potential reservoir averaging 1.5 km thickness, (3) high heat flow near the city, (4) warm waters (>30/sup 0/C) in municipal wells, (5) recent seismicity indicating active faulting, thereby, allowing the possibility of deep hydrothermal circulation, (6) high shallow (<30 m) temperature gradients (>100/sup 0/C/km) discovered in our drillholes, (7) deeper (<500 m) gradients from water wells exceeding 80/sup 0/C/km, and (8) chemical analyses of 88 groundwater samples yielding estimated base reservoir temperatures as high as 190/sup 0/C. An area of elevated shallow temperature gradients (less than or equal to 140/sup 0/C/km) was discovered a few kilometers west of Albuquerque by our 69 hole drilling program. Resistivity, magnetic, and gravity measurements combined with computer modeling suggests that heated ground water is forced closer to the surface here by flow over a buried ridge. A well drilled nearby yielded the highest recorded temperature in the Albuquerque area at its maximum depth (32.8/sup 0/C at 364 m). The deep gradient is 35/sup 0/C/km. An oil test well close by reported large volumes of water at 1 km; therefore, the possibility of a low temperature (>50/sup 0/C) geothermal resource exists west of Albuquerque at less than 1 km depth.
Date: July 1, 1983
Creator: Jiracek, G.R.; Swanberg, C.A.; Morgan, P. & Parker, M.D.
Partner: UNT Libraries Government Documents Department

Variable speed constant frequency constant voltage alternator. Annual report

Description: A test alternator is operated with digital control of its output frequency for variable shaft speed. The machine is a two-pole alternator with power removed through slip rings. The output frequency of the alternator is controlled by rotating the field by stepping through sixteen coils around the rotor. Usually four coils are active at one time. The rotating field in the stationary coils of the stator is controlled by microcircuits. The control circuits are constructed with available low-cost, low-power integrated circuits (ICs). The test results from the first test alternator indicate the feasibility of using this type of alternator to convert available wind power directly to usable 60 hertz power.
Date: July 1, 1980
Creator: Grannemann, W.W.; Yang, C.E. & Seo, P.H.
Partner: UNT Libraries Government Documents Department

Diffusion of gases in coals and chars: Final report, September 15, 1985--September 14, 1988

Description: Eight PSOC coals representing a wide range of rank and geographic origin have been subjected to a wide range of pore structure analysis methods as well as gas diffusion measurements. Pore structure analysis techniques employed included carbon dioxide and nitrogen adsorption, helium pycnometry, mercury porosimetry, and low-field NMR spin-lattice relaxation measurements. In principle, NMR pore structure analysis avoids many of the problems associated with conventional pore structure methods such as pore structure changes during drying, sample compression, network/percolation effects, pore shape assumptions, and a limited pore size range. Spin-lattice relaxation measurements were conducted at a proton frequency of 20 MHz and 303 K using water contained in the coal pores. Pore size distributions were obtained via deconvolution of the NMR relaxation measurements using the method of regularization and application of the ''two fraction-fast exchange'' model of pore fluid behavior. A qualitative comparison of the NMR pore size distributions and surface areas (CO/sub 2//N/sub 2/) yielded good agreement. Monodisperse and bidisperse pore size distributions were noted with pore volume in the size range of <0.5 nm to 0.5 ..mu..m. Effective diffusivities of methane and nitrogen were measured at 303 K and ambient pressure using a pulse tracer analysis method. 37 refs., 14 figs., 5 tabs.
Date: January 1, 1988
Creator: Smith, D.M.
Partner: UNT Libraries Government Documents Department

Chirping for efficiency enhancement of the free-electron laser

Description: One-dimensional numerical studies have been made of free-electron laser oscillators in which the incident electron energy varies (chirps) as a function of time over each micropulse. Optical radiation resonant with such micropulses is chirped in frequency. Highest calculated efficiency (up to 8.1% for wavelengths near 10 ..mu..m) has been obtained in cases where the optical pulse at saturation is short compared to the slippage. 8 refs., 7 figs., 1 tab.
Date: January 1, 1988
Creator: Moore, G.T. & Goldstein, J.C.
Partner: UNT Libraries Government Documents Department

Conservatism in least favorable response analysis and testing

Description: In order to assure that mechanical structures can meet design requirements it is desirable to test a structure using an input which is conservative but not a severe overtest. One method available for the specification of shock tests is the method of least favorable response. This method can be used analytically or in the laboratory and is guaranteed to provide tests which are conservative, at least in one sense. When the impulse response function, or equivalently the frequency response function, is available between a point of interest on a structure and the input point of the structure, and when we know the real function which envelops the modulus of the Fourier transform of all possible inputs which might excite the structure, then the method of least favorable response can be used to find an upper bound on the response which the point of interest on the structure can realize. We use this in the analysis of structural peak response. In the laboratory the least favorable response is generated experimentally, for example, by testing the structural unit on a shake table. If the structure survives the laboratory test, then we assume that it could survive any input in the class of inputs whose Fourier transform moduli are enveloped by the function used in the analysis. The objective of this study was to analyze the inherent conservatism of the method of least favorable response. A technique that can be used to do this is demonstrated. First, the method of least favorable response is reviewed and how it is used analytically and experimentally is demonstrated. Next the technique used to measure the conservatism in a least favorable response test is developed. Finally, the method is applied in some numerical examples where the degree of conservatism in the tests of some specific structures is ...
Date: January 1, 1980
Creator: Paez, T.L.
Partner: UNT Libraries Government Documents Department

Analysis of heat and mass transfer in sub-seabed disposal of nuclear waste

Description: A mathematical basis is developed for the prediction of thermal and radionuclide transport in marine sediments. The theory is applied to the study of radioactive waste disposal by emplacement, in specially designed containers, well below the sediment/water interface. Numerical results are obtained for a specified model problem through use of two computer programs designed primarily for the analysis of waste disposal problems. One program (MARIAH) provides descriptions of the temperature and velocity fields induced by the presence of a container of thermally active nuclear waste. A second program (IONMIG), which utilizes the results of the thermal analysis, is used to provide predictions for the migration of four representative radionuclides: /sup 239/Pu, /sup 137/Cs, /sup 129/I, and /sup 99/Tc.
Date: January 1, 1980
Creator: Hickox, C. E.; Gartling, D. K.; McVey, D. F.; Russo, A. J. & Nuttall, H. E.
Partner: UNT Libraries Government Documents Department

Progress on the Los Alamos heavy-ion injector

Description: Heavy-ion fusion using an induction linac requires injection of multiple high-current beams from a pulsed electrostatic accelerator at as high a voltage as practical. Los Alamos National Laboratory is developing a 16-beam, 2-MeV, pulsed electrostatic accelerator for Al/sup +/ ions. The ion source will use a pulsed metal vapor arc plasma. A biased grid will control plasma flux into the ion extraction region. This source has achieved a normalized emittance of epsilon/sub n/ < 3.10/sup -7/..pi..-m-rad with Al/sup +/ ions. An 800 kV Marx prototype with a laser fired diverter is being assembled. The ceramic accelerating column sections have been brazed and leak tested. Voltage hold off on a brazed sample was more than doubled by selective removal of the Ticusil braze fillet extending along the ceramic. A scaled test module held 250 kV for 50 ..mu..s, giving confidence that the full module can hold 175 kV per section. The pressure vessel should be received in June 1986. High-voltage testing of a 1 MV column will begin by early 1987.
Date: January 1, 1986
Creator: Wilson, D.C.; Riepe, K.B.; Ballard, E.O.; Meyer, E.A.; Shurter, R.P.; Van Haaften, F.W. et al.
Partner: UNT Libraries Government Documents Department

Measurement of C/sub SS/ and. delta. sigma/sub T/ in pp elastic scattering at 500, 650 and 800 MeV (Experiment 512, EPB)

Description: A measurement of the pp elastic scattering spin parameters are essential in determining the I = 1 amplitudes as well as contributing to the determination of phase shifts. The measurements of single and double-spin correlation parameters at each angle and energy will have a large impact on these programs. Furthermore, a study of the two-spin elastic scattering parameters may reveal possible new structure in the pp system. Experiment 512 has its objective to measure C/sub SS/ in the angular region 20/sup 0/ less than or equal to theta/sub c.m./ less than or equal to 90/sup 0/ and at energies of 500, 650 and 800 MeV. The EPB beam, polarized in the S direction, was incident to a target also polarized in the S direction. The scattered particles were detected in a single arm spectrometer which rotated from about 0/sup 0/ to 45/sup 0/ in the lab. A simultaneous measurement of ..delta..sigma/sub T/ was made using the transmission counters from Experiment 498 downstream of the spectrometer. Results are presented. (WHK)
Date: January 1, 1983
Creator: Imai, K. & Greene, S.
Partner: UNT Libraries Government Documents Department

Calibration of solar radiation measuring instruments. Final report

Description: A review of solar radiation measurement of instruments and some types of errors is given; and procedures for calibrating solar radiation measuring instruments are detailed. An appendix contains a description of various agencies who perform calibration of solar instruments and a description of the methods they used at the time this report was prepared. (WHK)
Date: November 1, 1979
Creator: Bahm, R J & Nakos, J C
Partner: UNT Libraries Government Documents Department

LASL/UNM solar economic performance code: a basic primer

Description: The LASL/UNM solar economic performance code (model) has been developed to assist in the evaluation of market potential for residential passive solar heating systems on a nationwide basis. Components of the model can be divided into three major categories: inputs, methodology, and output. Each of these categories are briefly described.
Date: January 1, 1979
Creator: Roach, F.; Ben-David, S. & Kirschner, C.
Partner: UNT Libraries Government Documents Department

Passive solar economics in 15 northwest locations

Description: The economic performance of Trombe wall and direct gain passive solar heating designs are evaluated using the LASL/UNM solar economic performance code. Both designs are integrated into a ranch style tract home concept thereby facilitating intra-regional comparison. The economic performance of these systems is evaluated for 15 sites in the Northwest region. Space heating loads have been locally specified. System sizes have been optimized against the natural gas and electric resistance heating alternatives, the current price and future escalation of which is established for each locale. Sensitivity analysis is conducted to determine the maximum competitive add-on costs for each system under a specified set of energy price, solar performance and economic conditions.
Date: August 10, 1979
Creator: Kirschner, C.; Ben-David, S. & Roach, F.
Partner: UNT Libraries Government Documents Department

Residential passive solar systems: regional sensitivity to system performance costs, and alternative prices

Description: The economic potential of two passive space heating configurations are analyzed. These are a masonry thermal storage wall (Trombe) and a direct gain system - both with night insulation. A standard tract home design for each of the two passive systems is being used throughout the analysis to allow interregional comparisons. The economic performance of these two systems is evaluated on a regional basis (223 locations) throughout the United States. For each of the two conventional energy types considered (electricity and natural gas), sensitivity analysis is conducted to determine the impact of alternative fuel price escalation rates and solar costs upon feasibility of the two solar systems. Cost goals for solar system prices are established under one set of future fuel prices and stated economic conditions. (MOW)
Date: January 1, 1979
Creator: Kirschner, C.; Ben-David, S. & Roach, F.
Partner: UNT Libraries Government Documents Department

Energy optimization in DOD facilities

Description: A static linear programming formulation (management tool) of energy optimization problems on military bases has been developed to assist each of the military services in their planning activities and budgetary allocation decisions. Several objective functions have been defined, resulting in two types of model capabilities: minimization of capital costs (investments) subject to a number of energy and dollar constraints and the maximization of energy savings subject to capital and operating fund budget restrictions and minimum energy performance goals. The management tool defines various levels of aggregation in terms of: (1) geographical boundaries; (2) end-use energy demand; (3) building type characteristics; (4) conservation options; (5) renewable energy and alternative fuel technologies; and (6) a limited set of advanced energy technology options. Both a technical description of and a user's guide to the principal model components and operational attributes of the constructed DOD energy optimization model are presently being prepared. Two key questions are briefly reviewed within the context of preliminary results obtained from application of the developed model to two Air Force Logistics Command installations: (1) the geographical distribution of military construction dollars under a set of budgetary and energy performance constraints; and (2) the selection of energy supply technologies - conventional conservation, renewable, and advanced - that simultaneously meet demand at least cost and satisfy a set of conflicting energy and budgetary goals. Temporal aspects of the problem are handled on a year-by-year basis, with information from a previous year's optimal investment and associated energy savings included in each succeeding year's decision criteria. Benefits and costs of the budgetary and energy allocation results are evaluated as part of the allocation decisions.
Date: January 1, 1981
Creator: Roach, F.; Kirschner, C. & Salmon, R.
Partner: UNT Libraries Government Documents Department

Demonstration salt gradient solar pond. Fourth semiannual progress report, November 1, 1978-June 30, 1979

Description: A thorough account is given of a solar pond study underway at the University of New Mexico since 1975. This report consists of the Ph.D. dissertation of Federica Zangrando entitled Observation and Analysis of a Full-Scale Experimental Salt Gradient Solar Pond. The stability condition for a non-constant gradient, doubly-diffusive system is derived and a prescription for the routine detection of potential instabilities is presented. Techniques for handling unstable regions are described. Conclusions so far strongly support the viability of the solar pond concept. Salt gradient ponds appear to have a very definite niche in the ecology of energy production.
Date: July 10, 1979
Creator: Zangrando, F. & Bryant, H.C.
Partner: UNT Libraries Government Documents Department