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Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems

Description: A Photovoltaic Metallization Research Forum, under the sponsorship of the Jet Propulsion Laboratory's Flat-Plate Solar Array Project and the US Department of Energy, was held March 16-18, 1983 at Pine Mountain, Georgia. The Forum consisted of five sessions, covering (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques and (5) future metallization challenges. Twenty-three papers were presented.
Date: November 15, 1983
Partner: UNT Libraries Government Documents Department
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Broad-band soft x-ray diagnostic instruments at the LLNL Novette laser facility

Description: Complementary broad-band instruments have been developed to measure time dependent, absolute soft x-ray spectra at the Lawrence Livermore National Laboratory (LLNL) Nd glass laser irradiation facilities. Absolute flux measurements of x rays emitted from laser-produced plasmas are important for understanding laser absorption and energy transport. We will describe two new 10-channel XRD systems that have been installed at the LLNL Novette facility for use in the 0.15- to 1.5-keV range. Since XRD … more
Date: September 15, 1983
Creator: Tirsell, K.G.; Lee, P.H.Y.; Nilson, D.G. & Medecki, H.
Partner: UNT Libraries Government Documents Department
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Inertial effects in laser-driven ablation

Description: The gasdynamic partial differential equations (PDE's) governing the motion of an ablatively accelerated target (rocket) contain an inertial force term that arises from acceleration of the reference frame in which the PDE's are written. We give a simple, intuitive description of this effect, and estimate its magnitude and parametric dependences by means of approximate analytical formulas inferred from our computer hydrocode calculations. Often this inertial term is negligible, but for problems i… more
Date: July 15, 1983
Creator: Harrach, R.J.; Szeoke, A. & Howard, W.M.
Partner: UNT Libraries Government Documents Department
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Charged-particle beam: a safety mandate

Description: The Advanced Test Accelerator (ATA) is a recent development in the field of charged particle beam research at Lawrence Livermore National Laboratory. With this experimental apparatus, researchers will characterize intense pulses of electron beams propagated through air. Inherent with the ATA concept was the potential for exposure to hazards, such as high radiation levels and hostile breathing atmospheres. The need for a comprehensive safety program was mandated; a formal system safety program w… more
Date: July 15, 1983
Creator: Young, K.C.
Partner: UNT Libraries Government Documents Department
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Magnetic mirror fusion power systems

Description: No Description Available.
Date: September 15, 1983
Creator: Gordon, J. D. & Logan, B. G.
Partner: UNT Libraries Government Documents Department
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Review of the Tandem Mirror Experiment-Upgrade (TMX-U) machine-parameter-instrumentation system

Description: The Tandem Mirror Experiment-Upgrade (TMX-U) machine consists of seven major machine subsystems: magnet system, neutral beam system, microwave heating (ECRH), ion heating (ICRH), gas fueling, stream guns, and vacuum system. Satisfactory performance of these subsystems is necessary to achieve the experimental objectives planned for TMX-U operations. Since the performance quality of the subsystem is important and can greatly affect plasma parameters, a 233-channel instrumentation system has been … more
Date: November 15, 1983
Creator: Kane, R. J.; Coffield, F. E.; Coutts, G. W. & Hornady, R. S.
Partner: UNT Libraries Government Documents Department
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Laboratory Physical Model for Pattern Injection in Geothermal Systems

Description: In the development of geothermal sources for power generation, production of geothermal fluids as well as reinjection becomes an important aspect for significant heat extraction from the reservoir rock. The purpose of this work was to understand how cold water injection in five spot pattern affected the temperature distributions and production pressures in a physical model with a constant temperature heat source. The production and injection rates were varied as well as their respective depths.… more
Date: December 15, 1983
Creator: Parlaktuna, M. & Okandan, E.
Partner: UNT Libraries Government Documents Department
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One Component Two Phase Flow in Horizontal and Vertical Ducts: Some Basic Considerations

Description: For a description and analysis of the flow they consider the conservation equations of the two phases separately, but in thermal and mechanical equilibrium, coupled by the itnerface shear forces (two fluid model, drift flux model). Coupling may be weak or strong, depending on Froude and Mach numbers of the flow. The fluid is highly compressible, not because the individual phases move at such speeds that their individual density changes are significant but because evapiration (phase change) resu… more
Date: December 15, 1983
Creator: Maeder, Paul F.; Dickinson, David A. & Nikitopoulos, Dimitris E.
Partner: UNT Libraries Government Documents Department
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Design and Development of a Test Facility to Study Two-Phase Steam/Water Flow in Porous Media

Description: The concept of relative permeability is the key concept in extending Darcy's law for single phase flow through porous media to the two-phase flow regime. Relative permeability functions are needed for simulation studies of two-phase geothermal reservoirs. These are poorly known inspite of considerable theoretical and experimental investigations during the last decade. Since no conclusive results exist, many investigators use ad hoc parametrization, or adopt results obtined from flow of oil and … more
Date: December 15, 1983
Creator: Verma, Ashok K.; Pruess, Karsten; Bodvarsson, G. S.; Tsang, C. F. & Witherspoon, Paul A.
Partner: UNT Libraries Government Documents Department
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Interpretation of Interference Data from the Klamath Falls, Oregon Geothermal Resource

Description: Data from a seven week pressure interference test in the Klamath Falls, Oregon geothermal resource have been analyzed. The data indicate that productive wells are fed by a highly permeable fracture network and that the less permeable matrix blocks contribute significantly to the reservoir storage capacity. Detailed analysis of data from two wells is presented. Data from both of the wells yield a reservoir permeability-thickness (kh) of approximately 1.3x10{sup 6} md-ft and a storativity of 6.8x… more
Date: December 15, 1983
Creator: Benson, S.M.
Partner: UNT Libraries Government Documents Department
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Pressure Transient Analysis for Large Scale Hydraulic Injections in the Carnmenellis Granite, England

Description: Large volume hydraulic injections into the Carnmenellis granite have been completed at the CSM Hot Dry Rock Project during the period October 1982 to July 1983, with small volume injections before and after this period. The effects of the injections on the hydraulic properties of the rock mass have been estimated by pressure transient analysis. The growth of the reservoir zone was tracked with microseismic locations, and the growth mechanism modeled with the computer program FRIP. The limited d… more
Date: December 15, 1983
Creator: Pine, R. J.
Partner: UNT Libraries Government Documents Department
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Gas Chemistry in Geothermal Systems

Description: Five new gas geothermometers are introduced. They are useful for predicting subsurface temperatures in water dominated geothermal systems. The geothermometers use data on CO{sub 2}, H{sub 2}S and H{sub 2} concentrations in fumarole steam as well as CO{sub 2}/H{sub 2} and H{sub 2}S/H{sub 2} ratios. It is demonstrated that the gas composition of fumarole steam may be used with or withour drillhole data to evaluate steam condensation in the upflow zones of geothermal systems. Uncertainty exists, h… more
Date: December 15, 1983
Creator: Arnorsson, Stefan & Gunnlaugsson, Einar
Partner: UNT Libraries Government Documents Department
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Nonisothermal Injectivity Index can Infer Well Productivity and Reservoir Transmissivity

Description: In geothermal wells injection tests are commonly used to obtain well and reservoir data. These tests are typically conducted in a series of step rates followed or preceded by a complete shutin. Usually the temperature of the injected fluid is different from that of the reservoir fluid. Because of the strong temperature dependence of fluid viscosity and to a lesser extent, fluid density, nonisothermally related pressure responses must be considered. The nonisothermal isjectivity index obtained f… more
Date: December 15, 1983
Creator: Sigurdsson, Omar; Bodvarsson, Gudmundur S. & Stefansson, Valgardur
Partner: UNT Libraries Government Documents Department
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Analysing Spinner Measurements from Well Tests Using Computerized Interpretation Techniques

Description: The development of reliable spinner tools may help avoid much of the ambiquity which often accompanies well tests in geothermal wells, due to interlayer flows through the well bore. However, the use of both pressure and flow rate changes requires new methods of well test interpretation. The Stanford Geothermal Program has been developing microcomputer-based techniques for the simultaneous analysis of pressure and flow rate measurements. There are two key steps in the procedure. Firstly, the non… more
Date: December 15, 1983
Creator: Horne, Roland N.; Guillot, Alain & Rosa, Adalberta
Partner: UNT Libraries Government Documents Department
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Geothermal Field Developments in Japan

Description: The present situation of the geothermal field developments in Japan is such that eight geothermal power stations are being operated, while there are sill many geothermal areas to be explored. Up to this day, the target of geothermal exploration has mainly been the areas by surface geological survey and the existing geothermal reservoirs are located not deeper than 1,500m depth. Recent geothermal energy development shows a trend from the study on vapor dominated of liquid dominated hydrothermal … more
Date: December 15, 1983
Creator: Hirakawa, Seiichi
Partner: UNT Libraries Government Documents Department
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Geothermal Field Development in the European Community Objectives, Achievements and Problem Areas

Description: Achievements and problem areas are reviewed with respect to various engineering implications of geothermal field development in the European Community (EC). Current and furture development goals address three resource settings. (a) low enthalpy sources (30-150{degrees}C), an outlook common to all Member states as a result of hot water aquifers flowing in large sedimentary units with normal heat flow, widespread thoughout the EC; (b) high enthalpy sources (<150{degrees}C) in areas of high heat f… more
Date: December 15, 1983
Creator: Ungemach, Pierre
Partner: UNT Libraries Government Documents Department
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Mapping the Acid Stimulation in the Beowawe Geothermal Field Using Surface Electrical Potentials

Description: A surface electrical potential system was fielded during the chemical stimulation of the Rossi 21-19 well in the Beowawe Geothermal Field. The technique, which measures variations in resistivity resulting from the flow of conductive fluid into the reservoir, was not only shown to be highly sensitive, not only to the chemical treatment, but also to the in situ conductive zones before any acid injection. A review of the experiment and a preliminary interpretation of the data are presented. The da… more
Date: December 15, 1983
Creator: Hart, Carolyne M.; Engi, Dennis & Morris, Harris E.
Partner: UNT Libraries Government Documents Department
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A Status Report on the Exploitation Conditions of the Ahuachapan Geothermal Field

Description: The present exploitation conditions of the Ahuachapan field are discussed. The high well density in a small area has resulted in a significant reservoir pressure decrease due to the inherent reservoir over-exploitation. The average pressure in the exploitation zone has decreased from the 1975 value of 34 kg/cm{sup 2} to the May 1983 value of 23 kg/cm{sup 2}. The production decline characteristics of the Ahuachapan wells were examined, concluding that all wells but Ah-22 show exponential decline… more
Date: December 15, 1983
Creator: Rivera-R., Jesus; Vides-R., Alberto; Cuellar, Gustavo; Samaniego-V., Fernando & Neri-I, Gustavo
Partner: UNT Libraries Government Documents Department
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Radial Flow of Pressured Hot Water Through Narrow Cracks

Description: Geothermal wells discharging hundreds of tons/hour of steam-water mixtures may be supplied at depth from one very narrow crack of width 1 to 2 mm, or alternatively, from some hundreds of hairline cracks. In the former case, turbulent flow takes place out to tens of meters from the well while the sum of frictional and kinetic pressure-drop indicates the flashing distance to be of the order of 10 cm from the well wall for pressure-temperature equilibrium. However it is unlikely that equilibrium o… more
Date: December 15, 1983
Creator: James, Russell
Partner: UNT Libraries Government Documents Department
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Disposal of Flashed Brine Dosed with CaCO{sub3} Scale Inhibitor: What Happens When the Inhibitor is Exhausted?

Description: A freshly flashed geothermal liquid, previously dosed with inhibitor and super-saturated with calcite was injected into another well where it displaced an unflashed counterpart of itself around the wellbore. Back-production of the injectate, and subsequently the native fluid, has yielded data for the rate that a scale inhibitor is degraded after injection. The circumstance also displays a novel mechanism whereby two fluids that do not physically mix never the less reactive with one another thro… more
Date: December 15, 1983
Creator: Michels, D. E.
Partner: UNT Libraries Government Documents Department
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Evaluating Geothermal Reserves with Application of Well Interference and Pressure Buildup Tests

Description: In order to evaluate geothermal reserves, it is necessary to estimate the porosity-thickness product of the reservoir. This paper deals with the method for estimating the porosity-thickness product of geothermal reservoirs by means of combining well interference and pressure buildup tests. A field study from the Chingshui geothermal area in Taiwan is given to illustrate the application of the method.
Date: December 15, 1983
Creator: Chiu, T. L.; Chiang, C. Y. & Wu, T. S.
Partner: UNT Libraries Government Documents Department
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Numerical Simulations of the Hydrothermal System at Lassen Volcanic National Park

Description: The hydrothermal system in the vicinity of Lassen Volcanic National Park contains a central region of fluid upflow in which steam and liquid phases separate, with steam rising through a parasitic vapor-dominated zone and liquid flowing laterally toward areas of hot spring discharge south of the Park. A simplified numerical model was used to simulate the 10,000-20,000 year evolution of this system and to show that under certain circumstances fluid withdrawal from hot-water reservoirs south of th… more
Date: December 15, 1983
Creator: Sorey, Michael L. & Ingebritsen, Steven E.
Partner: UNT Libraries Government Documents Department
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One Year Experience with Portable Back-Pressure Turbines in Los Azufres

Description: This paper contains the experience gained after one year operating five 5 MW portable, back-pressure, geothermal power plants at Los Azufres. A brief description of the field and te equipment is given. Cost figures of the whole installation and a list of what they believe are the advantages and disadvantages is also presented. The main conclusion is that the use of this type of turbogenerators is quite attractive in new undeveloped fields and also in countries with financial problems where init… more
Date: December 15, 1983
Creator: Hiriart, Gerardo L.
Partner: UNT Libraries Government Documents Department
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Permeability Reduction Due to Precipitation of Quartz under Nonisothermal Conditions

Description: Many problems concerning the origin and exploitation of geothermal reservoirs demonstrate the need for models of reactive-solute transport. Of particular interest to us is the coupling between dissolution/precipitation reactions and transient-flow behavior. In an effort to account for observed flow-rate reductions during experiments on samples of granite held in a temperature gradient (summarized at this meeting in 1981 by Moore and others), we examine the effect of quartz precipitation on flui… more
Date: December 15, 1983
Creator: Keith, Laura A.; Delaney, Paul T. & Moore, Diane E.
Partner: UNT Libraries Government Documents Department
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