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Reducing long-term reservoir performance uncertainty
Reservoir performance is one of the key issues that have to be addressed before going ahead with the development of a geothermal field. In order to select the type and size of the power plant and design other surface installations, it is necessary to know the characteristics of the production wells and of the produced fluids, and to predict the changes over a 10--30 year period. This is not a straightforward task, as in most cases the calculations have to be made on the basis of data collected before significant fluid volumes have been extracted from the reservoir. The paper describes the methodology used in predicting the long-term performance of hydrothermal systems, as well as DOE/GTD-sponsored research aimed at reducing the uncertainties associated with these predictions. 27 refs., 1 fig.
Date:
April 1, 1988
Creator:
Lippmann, M.J.
Object Type:
Article
System:
The UNT Digital Library
Energy Dependence of Complete and Incomplete Fusion in the /sup 28/Si + /sup 12/C Reaction
To study possible entrance channel effects in certain heavy-ion reactions and to investigate the dependence of such processes on heavier projectiles, measurements involving a pulsed /sup 28/Si beam and /sup 12/C target were performed using the ANL ATLAS facility. TOF measurements at /sup 28/Si bombarding energies of 11.0, 14.3, and 16.1 MeVu were carried out to establish the total evaporation residue cross section behavior for complete and incomplete fusion. 4 figs., 1 tab.
Date:
January 1, 1988
Creator:
Mateja, J. F.; Vineyard, M. F.; Kovar, D. G.; Beck, C.; Henderson, D. J.; Janssens, R. V. F. et al.
Object Type:
Article
System:
The UNT Digital Library
Overview of the SDI (Strategic Defense Initiative) Program in short wavelength chemical lasers
Advanced chemical lasers promise to be effective space-based weapons against responsive threats. In this program, we are developing both CW and pulsed concepts for achieving this goal. Certain approaches may also be appropriate as ground-based weapons and fusion drivers. 12 refs., 1 fig., 5 tabs.
Date:
January 1, 1988
Creator:
Jones, C.R.
Object Type:
Article
System:
The UNT Digital Library
High-resolution neutron transmission measurements on /sup 235/U, /sup 239/Pu, and /sup 238/U
High-resolution transmission measurements have been made on three sample thicknesses of both /sup 235/U and /sup 239/Pu at liquid nitrogen temperature and also on three of /sup 238/U at room temperature using neutrons from the water-moderated ORELA target. The data on /sup 235/U and /sup 239/Pu from 1 to 10,000 eV were obtained using /sup 6/Li glass scintillation detectors at 17.909-and 80.394-m flight paths. The /sup 238/U data from 1 to 100 keV were obtained using a new NE 110 proton-recoil scintillation detector at a 210.558-m flight path.
Date:
January 1, 1988
Creator:
Harvey, J.A.; Hill, N.W.; Perey, F.G.; Tweed, G.L. & Leal, L.
Object Type:
Article
System:
The UNT Digital Library
The effective stiffness of nuclei near magic numbers
This paper trys to explain the rapid increase in the apparent size of the rubidium isotope nuclei around the magic number N = 50. Droplet and deformation models are used to evaluate the measured data. 6 refs., 4 figs.
Date:
February 1, 1988
Creator:
Meyers, W.D. & Rozmej, P.
Object Type:
Article
System:
The UNT Digital Library
Capture reactions of /sup 40/Ca and /sup 48/Ca with targets of /sup 197/Au and /sup 208/Pb
The reactions of /sup 40/Ca and /sup 48/Ca with targets of /sup 197/Au and /sup 208/Pb have been measured in the region from below the interaction barrier to about twice the barrier energy. The fission-like fragments were detected in a pair of position-sensitive, multi-wire proportional counters and were identified from measurements of position and time using two-body kinematics. In the region above the barrier the cross sections for capture are less than those given by the touching condition, indicating that an /open quotes/extra push/close quotes/ is required to induce capture. The observations for /sup 40/Ca and /sup 48/Ca show different fissilities for the onset of the extra push and indicate that charge equilibration may be an important factor governing capture reactions. Below the barrier the cross sections show an enhancement relative to the prediction for a one dimensional barrier. The enhancements are larger for /sup 40/Ca than for /sup 48/Ca (for both targets) and this is in qualitative agreement with predictions based on the coupling of the relative motion to low-lying collective states. Both above and below the barrier, we find that the change in the light partner, from /sup 48/Ca to /sup 40/Ca, has a larger effect on the …
Date:
March 1, 1988
Creator:
Stokstad, R.; Chan, Y.; Chavez, E.; Di Gregorio, D.; di Tada, M.; Gazes, S. et al.
Object Type:
Article
System:
The UNT Digital Library
Ecological Studies Related to Construction of the Defense Waste Processing Facility on the Savannah River Site
The Savannah River Ecology Laboratory has completed 10 years of ecological studies related to the construction of the Defense Waste Processing Facility (DWPF) on the Savannah River Site. This progress report examines water quality studies on streams peripheral to the DWPF construction site and examines the effectiveness of refuge ponds'' in ameliorating the effects of construction on local amphibians. Individual papers on these topics are indexed separately. 93 refs., 15 figs., 15 tabs. (MHB)
Date:
December 1, 1988
Creator:
Scott, David E.; Pechmann, Joesph H. K.; Knox, John N.; Estes, Ruth A.; McGregor, JoAnne H. & Bailey, K. (ed.)
Object Type:
Report
System:
The UNT Digital Library
An HVEM study of displacement cascade damage in Nb/sub 3/Sn at 13 K
TEM images of the martensite structure in Nb/sub 3/Sn were recorded at various temperatures between 12 and 30/degree/K. The transition to the superconducting state was observed by a slight deflection of the electron beam due to a perturbation of the magnetic field of the objective lens at the sample. The primary interest is in irradiation effects due to fast neutrons from a fusion reactor, and therefore ion irradiation conditions that are somewhat comparable to this were selected. These consisted of 50 keV Xe/sup /plus// irradiations to simulate neutron produced cascades in a near surface region and 1.5 Mev Kr/sup /plus// to produce cascade damage through a greater sample thickness. Defect images were obtained as a function of ion dose at 13/degree/K using both fundamental and superlattice dark-field reflections in two-beam conditions. For 50 keV Xe/sup /plus// irradiations at 13/degree/K the defect yields were quite low at low ion doses where individual defect cascades are well separated. At higher ion doses when significant cascade overlap is present, defect density and contrast became greater than expected. Annealing to room temperature produced a large increase in defect density. Irradiation by 1.5 MeV Kr/sup /plus// at 15/degree/K removed the martensite structure by an ion …
Date:
February 1, 1988
Creator:
Kirk, M. A.; Baker, M. C.; Kestel, B. J.; Weber, H. W. & Kampwirth, R. T.
Object Type:
Article
System:
The UNT Digital Library
Pulsed CO sub 2 laser processing of thin ion-implanted silicon layers
We show that extremely shallow ({approx lt} 800 {Angstrom}) melt depths can be easily obtained by irradiating a thin heavily doped silicon layer with a CO{sub 2} laser pulse. Since the absorption of the CO{sub 2} laser pulse is dominated by free-carrier transitions, the beam heating occurs primarily in the thin degenerately doped film. For CO{sub 2} pulse-energy densities exceeding a threshold value, surface melting occurs and the reflectivity of the incident laser pulse increases abruptly to about 90%. This large increase in the reflectivity acts like a switch to reflect almost all of the energy in the remainder of the pulse, thereby greatly reducing the amount of energy available to drive the melt front to deeper depths in the material. Transmission electron microscopy shows no extended defects in the near-surface region after laser irradiation, and van der Pauw electrical measurements verify that 100% of the implanted arsenic dopant is electrically active. 8 refs., 3 figs., 1 tab.
Date:
January 1, 1988
Creator:
James, R.B. (Sandia National Labs., Livermore, CA (United States)) & Christie, W.H. (Oak Ridge National Lab., TN (United States))
Object Type:
Article
System:
The UNT Digital Library
Design analysis and optimization of self-cooled lithium blankets and shields
A study of self-cooled lithium blankets was carried out to define the performance of these blankets and to determine the potential to operate at the maximum possible values of the performance parameters. The main design parameters considered during the course of the study were the tritium breeding ratio, the blanket energy multiplication factor, the energy fraction lost to the shield, the total blanket thickness, the reflector material selection, and the compositions of the different blanket zones. Another study was carried out to determine materials, compositions, arrangements, and thickness of the shield zone for the reference blanket. Helium and water-cooled shields were optimized for the inboard and outboard sections of the reactor. Based on the above two studies, the reference blanket and shield configurations were developed for the ANL Tokamak Power Systems Study. The helium-cooled shield was selected for use with liquid metal blankets to reduce safety concerns related to lithium-water reactivity. This helium-cooled shield provides shielding characteristics similar to a conventional water-cooled shield. The analyses and results from these studies are the subject of this paper. 12 refs., 4 figs., 2 tabs.
Date:
February 1, 1988
Creator:
Gohar, Y.
Object Type:
Article
System:
The UNT Digital Library
Experimental and analytical studies of passive shutdown heat removal from advanced LMRs (liquid metal reactors)
A facility designed and constructed to demonstrate the viability of natural convection passive heat removal systems as a key feature of innovative LMR Shutdown Heat Removal (SHR) systems is in operation at Argonne National Laboratory (ANL). This Natural Convection Shutdown Heat Removal Test Facility (NSTF) has investigated the heat transfer performance of the GE/PRISM passive design. This initial series of experiments simulates the air-side geometry of the PRISM Radiant Reactor Vessel Auxiliary Cooling System (RVACS). The NSTF operates in either a uniform heat flux mode and a uniform temperature mode at the air/guard vessel interface. Analysis of the RVACS performance data indicates excellent agreement with pretest analytical predictions. Correlation analysis presents the heat transfer data in a form suitable for use in LMR design and verification of analytical studies.
Date:
January 1, 1988
Creator:
Pedersen, D.; Heineman, J.; Stewart, R.; Anderson, T.; Lottes, P. & Tessier, J.
Object Type:
Article
System:
The UNT Digital Library
Two-photon (VUV + visible) resonance ionization spectroscopy of molecular hydrogen
Two-photon transitions have been examined in molecular hydrogen using coherent vacuum ultraviolet (VUV) photons at a fixed wavelength of 118 nm and a tunable photon from a dye laser. Though the VUV intensity is very weak (/approximately/100 nJ per pulse) it was utilized very efficiently since most VUV photons in the ionoization region were absorbed. This is the first time that coherent VUV light has been employed with tunable visible light for the production of two-photon spectra and the measurement of two-photon rates. A new parameter is proposed for direct comparison of the data from various two-photon experiments. 4 refs., 2 figs., 1 tab.
Date:
April 1, 1988
Creator:
McCann, M.P.; Chen, C.H. & Payne, M.G.
Object Type:
Article
System:
The UNT Digital Library
An outdoor test facility for the large-scale production of microalgae
The goal of the US Department of EnergySolar Energy Research Institute's Aquatic Species Program is to develop the technology base to produce liquid fuels from microalgae. This technology is being initially developed for the desert Southwest. As part of this program an outdoor test facility has been designed and constructed in Roswell, New Mexico. The site has a large existing infrastructure, a suitable climate, and abundant saline groundwater. This facility will be used to evaluate productivity of microalgae strains and conduct large-scale experiments to increase biomass productivity while decreasing production costs. Six 3-m/sup 2/ fiberglass raceways were constructed. Several microalgae strains were screened for growth, one of which had a short-term productivity rate of greater than 50 g dry wt m/sup /minus/2/ d/sup /minus/1/. Two large-scale, 0.1-ha raceways have also been built. These are being used to evaluate the performance trade-offs between low-cost earthen liners and higher cost plastic liners. A series of hydraulic measurements is also being carried out to evaluate future improved pond designs. Future plans include a 0.5-ha pond, which will be built in approximately 2 years to test a scaled-up system. This unique facility will be available to other researchers and industry for studies on microalgae …
Date:
March 1, 1988
Creator:
Johnson, D.A.; Weissman, J. & Goebel, R.
Object Type:
Article
System:
The UNT Digital Library
Performance of the Los Alamos expanding telescope
An expanding telescope can produce a very low divergence particle beam, provided that the beam optics have sufficient quality in order not to introduce large aberrations. Even as late as two years ago there were no theoretical beamline codes, and little experimental work that could describe the third-order aberrations introduced by an expanding telescope. A project was undertaken at Los Alamos National Laboratory to perform these calculations, and to build a telescope to confirm the predictions. It was installed at Argonne National Laboratory during the summer of 1987 and tested in a 50 MeV H/sup /-// beam. The telescope consisted of a singlet eyepiece and triplet objective lens with a twenty times magnification. It performed to the design specifications of twenty-five micro-radians beam divergence with a parallel beam focus. The measured geometric aberrations were found to be in agreement with the computer calculations.
Date:
January 1, 1988
Creator:
Dombeck, T.W.
Object Type:
Article
System:
The UNT Digital Library
Idaho Habitat Evaluation for Off-Site Mitigation Record : Annual Report 1987.
The Idaho Department of Fish and Game has been monitoring and evaluating existing and proposed habitat improvement projects for steelhead (Salmo gairdneri) and chinook salmon (Oncorhynchus tshawytscha) in the Clearwater and Salmon River drainages over the last four years. Projects included in the evaluation are funded by, or proposed for funding by, the Bonneville Power Administration (BPA) under the Northwest Power Planning Act as off-site mitigation for downstream hydropower development on the Snake and Columbia rivers. A mitigation record is being developed to use increased smolt production at full seeding as the best measure of benefit from a habitat enhancement project. Determination of full benefit from a project depends on presence of adequate numbers of fish to document actual increases in fish production. The depressed nature of upriver anadromous stocks have precluded attainment of full benefit of any habitat project in Idaho. Partial benefit will be credited to the mitigation record in the interim period of run restoration. According to the BPA Work Plan, project implementors have the primary responsibility for measuring physical habitat and estimating habitat change. To date, Idaho habitat projects have been implemented primarily by the US Forest Service (USFS). The Shoshone-Bannock Tribes (SBT) have sponsored three …
Date:
April 1988
Creator:
Petrosky, Charles E. & Holubetz, Terry B.
Object Type:
Report
System:
The UNT Digital Library
Development of mild gasification process
Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.
Date:
July 1, 1988
Creator:
Chu, C. I. C. & Derting, T. M.
Object Type:
Report
System:
The UNT Digital Library
ACE: AMY CDC (Central Drift Chamber) Fast Track Finder
The central drift chamber (CDC) of the AMY detector at the TRISTAN e/sup /+//e/sup /-// collider features its fine granularity and multi-band structure. The tracking software named ACE which makes the most of these features shows an excellent performance for reconstruction of high multiplicity events with highly collimated jets. The obtained reconstruction efficiency is 97% for the particles coming from within 5 cm of the primary vertex with p/sub t/ /approx gt/ 500 MeVc in the simulated hadronic events. The processing time is on average less than 300 ms per hadronic event (simulated or real) on a FACOM M-382 computer. 3 refs., 5 figs.
Date:
January 1, 1988
Creator:
Mori, T.
Object Type:
Article
System:
The UNT Digital Library
Application of artificial intelligence to melter control: Realtime process advisor for the scale melter facility
The Defense Waste Processing Facility (DWPF) at the Savannah River Plant (SRP) is currently under construction and when completed will process high-level radioactive waste into a borosilicate glass wasteform. This facility will consist of numerous batch chemical processing steps as well as the continuous operation of a joule-heated melter and its off-gas treatment system. A realtime process advisor system based on Artificial Intelligence (AI) techniques has been developed and is currently in use at the semiworks facility, which is operating a 2/3 scale of the DWPF joule-heated melter. The melter advisor system interfaces to the existing data collection and control system and monitors current operations of this facility. The advisor then provides advice to operators and engineers when it identifies process problems. The current system is capable of identifying process problems such as feed system pluggages and thermocouple failures and providing recommended actions. The system also provides facilities normally with distributed control systems. These include the ability to display process flowsheets, monitor alarm conditions, and check the status of process interlocks. 7 figs.
Date:
January 1, 1988
Creator:
Edwards, Jr, R E
Object Type:
Article
System:
The UNT Digital Library
Covariance analysis of n + 7Li data for ENDF/B-VI
A new covariance analysis of n/plus//sup 7/Li experimental data has been completed for Version VI of ENDFB. The analysis basically updates our 1981 work for ENDFB-V.2 to include new data that has become available since that time and to incorporate cross correlations between different experiments. The bulk of the new measured data consists of some 10 new (or newly revised) tritium-production measurements involving about 70 new data points. The new analysis results in only small changes in the previous evaluation of the tritium-production cross section but significantly reduces the magnitudes of uncertainties due to the more extensive and accurate data base that was used.
Date:
January 1, 1988
Creator:
Young, P.G.
Object Type:
Article
System:
The UNT Digital Library
Environmental surveillance at Los Alamos during 1987
This report describes the environmental surveillance program conducted by Los Alamos National Laboratory during 1987. Routine monitoring for radiation and radioactive or chemical materials is conducted on the Laboratory site as well as in the surrounding region. Monitoring results are used to determine compliance with appropriate standards and to permit early identification of potentially undesirable trends. Results and interpretation of data for 1987 cover: external penetrating radiation; quantities of airborne emissions and liquid effluents; concentrations of chemicals and radionuclides in ambient air, surface and ground waters, municipal water supply, soils and sediments, and foodstuffs; and environmental compliance. Comparisons with appropriate standards, regulations, and background levels provide the basis for concluding that environmental effects from Laboratory operations are insignificant and do not pose a threat to the public, Laboratory employees, or the environment. 113 refs., 33 figs., 120 tabs.
Date:
May 1, 1988
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
A theoretical prediction of critical heat flux in forced convection boiling during power transients
In this paper, a theoretical prediction of critical heat flux (CHF) during power transients in forced convective boiling is presented. The analysis is restricted to the departure from nucleate boiling (DNB) type of CHF at low qualities. The developed theory is compared with the experimental data available in the literature. The agreement is favorable. The results are discussed in terms of the various parameters affecting the transient CHF. This new model also is compared with the semi-empirical transient CHF model in the literature.
Date:
January 1, 1988
Creator:
Pasamehmetoglu, K.O.; Nelson, R.A. & Gunnerson, F.S.
Object Type:
Article
System:
The UNT Digital Library
Solar thermal bowl concepts and economic comparisons for electricity generation
This study is aimed at providing a relative comparison of the thermodynamic and economic performance in electric applications for fixed mirror distributed focus (FMDF) solar thermal concepts which have been studied and developed in the DOE solar thermal program. Following the completion of earlier systems comparison studies in the late 1970's there have been a number of years of progress in solar thermal technology. This progress includes developing new solar components, improving component and system design details, constructing working systems, and collecting operating data on the systems. This study povides an update of the expected performance and cost of the major components, and an overall system energy cost for the FMDDF concepts evaluated. The projections in this study are for the late 1990's and are based on the potential capabilities that might be achieved with further technology development.
Date:
April 1, 1988
Creator:
Williams, T. A.; Dirks, J. A.; Brown, D. R.; Antoniak, Z. I.; Allemann, R. T.; Coomes, E. P. et al.
Object Type:
Report
System:
The UNT Digital Library
Nuclear-data evaluation based on direct and indirect measurements with general correlations
Optimum procedures for the statistical improvement, or updating, of an existing nuclear-data evaluation are reviewed and redeveloped from first principles, consistently employing a minimum-variance viewpoint. A set of equations is derived which provides improved values of the data and their covariances, taking into account information from supplementary measurements and allowing for general correlations among all measurements. The minimum-variance solutions thus obtained, which we call the method of ''partitioned least squares,'' are found to be equivalent to a method suggested by Yu. V. Linnik and applied by a number of authors to the analysis of fission-reactor integral experiments; however, up to now, the partitioned-least-squares formulae have not found widespread use in the field of basic data evaluation. This approach is shown to give the same results as the more commonly applied Normal equations, but with reduced matrix inversion requirements. Examples are provided to indicate potential areas of application. 10 refs.
Date:
January 1, 1988
Creator:
Muir, D.W.
Object Type:
Article
System:
The UNT Digital Library
Radioactive Waste Isolation in Salt: A Method for Evaluating the Effectiveness of Site Characterization Measurements
The approach presumes that measurements are undertaken to support performance predictions. A quantitative performance objective like groundwater travel time is compared with performance predictions. The approach recognizes that such predictions are uncertain because the measurements upon which they are based are uncertain. The effectiveness of measurement activities is quantified by an index, ..beta.., that reflects the number of standard deviations separating the best estimate of performance from the performance objective. Measurements that reduce the uncertainty in predictions lead to increased values of ..beta... Evaluating ..beta.. for a particular measurement scheme requires identifying the measured quantities that significantly affect prediction uncertainty. Sources of uncertainty are spatial variation, noise, estimation error, and measurement bias. Changing the measurement scheme to increase ..beta.. increases the likelihood of a performance objective being achieved or exceeded. The application of the ..beta..-index method to the Richton dome site in Mississippi focuses on uncertainties in hydraulic conductivity data in relation to groundwater travel time predictions. The ..beta.. values for four different measurement schemes for hydraulic conductivity are determined. 44 refs., 14 figs., 15 tabs.
Date:
March 1, 1988
Creator:
Ditmars, J. D.; Baecher, G. B.; Edgar, D. E. & Dowding, C. H.
Object Type:
Report
System:
The UNT Digital Library