147 Matching Results

Search Results

Advanced search parameters have been applied.
in subjects: "Pressure"  
prev Results: 25 - 48 next
open access

Beneficial effects of groundwater entry into liquid-dominated geothermal systems

Description: In all active liquid-dominated geothermal systems there is continuous circulation of mass and transfer of heat, otherwise they would slowly cool and fade away. In the natural state these systems are in dynamic equilibrium with the surrounding colder groundwater aquifers. The ascending geothermal fluids cool conductively, boil, or mix with groundwaters, and ultimately may discharge at the surface as fumaroles or hot springs. With the start of fluid production and the lowering of reservoir pressu… more
Date: April 1, 1990
Creator: Lippmann, M.J. (Lawrence Berkeley Lab., CA (USA)) & Truesdell, A.H. (Geological Survey, Menlo Park, CA (USA))
Partner: UNT Libraries Government Documents Department
open access

Response of ferritic steels to nonsteady loading at elevated temperatures

Description: High-temperature operating experience is lacking in pressure vessel materials that have strength levels above 586 MPa. Because of their tendency toward strain softening, we have been concerned about their behavior under nonsteady loading. Testing was undertaken to explore the extent of softening produced by monotonic and cyclic strains. The specific materials included bainitic 2 1/4Cr-1Mo steel, a micro-alloyed version of 2 1/4Cr-1Mo steel, a micro-alloyed version of 2 1/4Cr-1Mo steel containin… more
Date: April 1, 1984
Creator: Swindeman, R.W.
Partner: UNT Libraries Government Documents Department
open access

Method for chug classification. [BWR]

Description: A method is presented which classifies the late time condensation phenomena of chugging as it occurs in pressure suppression tests. The method uses a five (5) character letter code which describes both the spectral (frequency) and temporal characteristics of a chug event.
Date: April 1, 1981
Creator: McCauley, E.W.; Weaver, H.J. & Altenbach, T.J.
Partner: UNT Libraries Government Documents Department
open access

Method for chug classification

Description: A method is presented which classifies the late time condensation phenomena of chugging as it occurs in pressure suppression tests. The method uses a five (5) character letter code which describes both the spectral (frequency) and temporal characteristics of a chug event. 8 figures.
Date: April 1, 1981
Creator: McCauley, E.W.; Weaver, H.J. & Altenbach, T.J.
Partner: UNT Libraries Government Documents Department
open access

Oxidation of uranium studied by gravimetric and positron annihilation techniques

Description: Oxidation of uranium under various environmental conditions, and at relatively low temperature was investigated to fulfill the following objectives: (1) to try to determine the validity and usefulness of published data; (2) to investigate the oxidation of uranium from very low (<<0.13 kPa (1 Torr)) to relatively high (approx. 20 kPa (150 Torr)) water vapor pressures in the presence and absence of oxygen (approx. 1 vppM to approx. 63.73 kPa (479 Torr)), and to determine the pressure dependence o… more
Date: April 1, 1981
Creator: Colmenares, C.; Howell, R. & McCreary, T.
Partner: UNT Libraries Government Documents Department
open access

Interaction of cold-water aquifers with exploited reservoirs of the Cerro Prieto geothermal system

Description: Cerro Prieto geothermal reservoirs tend to exhibit good hydraulic communication with adjacent cool groundwater aquifers. Under natural state conditions the hot fluids mix with the surrounding colder waters along the margins of the geothermal system, or discharge to shallow levels by flowing up fault L. In response to exploitation reservoir pressures decrease, leading to changes in the fluid flow pattern in the system and to groundwater influx. The various Cerro Prieto reservoirs have responded … more
Date: April 1, 1990
Creator: Truesdell, A.H. (Geological Survey, Menlo Park, CA (USA)) & Lippmann, M.J. (Lawrence Berkeley Lab., CA (USA))
Partner: UNT Libraries Government Documents Department
open access

Hydrogen transport and storage in engineered glass microspheres

Description: New, high-strength, hollow, glass microspheres filled with pressurized hydrogen exhibit storage densities which make them attractive for bulk hydrogen storage and transport. The hoop stress at failure of our engineered glass microspheres is about 150,000 psi, permitting a three-fold increase in pressure limit and storage capacity above commercial microspheres, which fail at wall stresses of 50,000 psi. For this project, microsphere material and structure will be optimized for storage capacity a… more
Date: April 20, 1994
Creator: Rambach, G. D.
Partner: UNT Libraries Government Documents Department
open access

Design of a pressure/temperature logging system for geothermal applications

Description: Past memory logging tools have provided excellent pressure/temperature data when used in a geothermal environment, and they are easier to maintain and deploy than tools requiring an electric wireline connection to the surface. However, they are deficient since the tool operator is unaware of downhole conditions that could require changes in the logging program. Tools that make ``decisions`` based on preprogrammed scenarios can partially overcome this difficulty, and a suite of such memory tools… more
Date: April 1, 1994
Creator: Lysne, P. & Henfling, J.
Partner: UNT Libraries Government Documents Department
open access

Large-scale testing of in-vessel debris cooling through external flooding of the reactor pressure vessel in the CYBL facility

Description: The possibility of achieving in-vessel core retention by flooding the reactor cavity, or the ``flooded cavity``, is an accident management concept currently under consideration for advanced light water reactors (ALWR), as well as for existing light water reactors (LWR). The CYBL (CYlindrical BoiLing) facility is a facility specifically designed to perform large-scale confirmatory testing of the flooded cavity concept. CYBL has a tank-within-a-tank design; the inner 3.7 m diameter tank simulates… more
Date: April 1, 1994
Creator: Chu, T. Y.; Bentz, J. H.; Bergeron, K. D.; Slezak, S. E. & Simpson, R. B.
Partner: UNT Libraries Government Documents Department
open access

Decontamination and decommissioning the Tokamak Fusion Test Reactor

Description: The Tokamak Fusion Test Reactor (TFTR) is scheduled to complete its end-of-life deuterium-tritium (D-T) experiments in September 1994. The D-T operation will result in the TFTR machine structure becoming activated, and plasma facing and vacuum components will be contaminated with tritium. The resulting machine activation levels after a two year cooldown period will allow hands on dismantling for external structures, but require remote dismantling for the vacuum vessel. The primary objective of … more
Date: April 1, 1994
Creator: Walton, G. R.; Perry, E. D.; Commander, J. C.; Bush, H. & Spampinato, P. T.
Partner: UNT Libraries Government Documents Department
open access

SSC 50 mm collider dipole cryostat design

Description: The cryostat of a Superconducting Super Collider (SSC) dipole magnet consists of all magnet components except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, provide all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations, and must be manufacturable at … more
Date: April 1, 1992
Creator: Nicol, T. H.
Partner: UNT Libraries Government Documents Department
open access

A Baroclinic Model of turbulent dusty flows

Description: The problem considered here is the numerical simulation of the turbulent dusty flow induced by explosions over soil surfaces. Some of the unresolved issues are: (1) how much dust is scoured from such surfaces; (2) where does the dust go in the boundary layer; (3) what is the dusty boundary layer height versus time; (4) what are the dusty boundary layer profiles; (5) how much of the dust mass becomes entrained into the dust stem; and (6) where does the dust go in the buoyant cloud? The author pr… more
Date: April 1, 1992
Creator: Kuhl, A. L.
Partner: UNT Libraries Government Documents Department
open access

Scaling fluid content-pressure relations of different fluid systems in porous media

Description: Two-fluid-phase relations among fluid saturations (S) and pressures (P) have historically been used to predict S-P relations for three-fluid-phase systems consisting of a gas, nonaqueous phase liquid (NAPL), and water, because measurements of three-phase S-P relations are complex. Two-phase S-P relations of air-NAPL systems are generally used to predict the behavior between total-liquid saturations of three-phase systems and air-NAPL capillary pressures. Two-phase S-P relations of NAPL-water sy… more
Date: April 1, 1994
Creator: Lenhard, R. J.
Partner: UNT Libraries Government Documents Department
open access

On coupling impedances of pumping holes

Description: Coupling impedances of a single small hole in vacuum-chamber walls have been calculated at low frequencies. To generalize these results for higher frequencies and/or larger holes one needs to solve coupled integral equations for the effective currents. These equations are solved for two specific hole shapes. The effects of many holes at high frequencies where the impedances are not additive are studied using a perturbation-theory method. The periodic versus random distributions of the pumping h… more
Date: April 1, 1993
Creator: Kurennoy, S.
Partner: UNT Libraries Government Documents Department
open access

Aerosol filtration with steel fiber filters

Description: We have conducted an experimental study of aerosol penetration through a new high efficiency steel fiber filter and filter media that we developed in cooperation with Pall Corporation. Our previous studies have shown that sintered steel fiber media have significant improvements in higher filter efficiency and lower pressure drop than the previous steel filter technology based on sintered powder metal media. In the present study, we have measured the penetration of dioctyl sebacate (DOS) aerosol… more
Date: April 1, 1993
Creator: Bergman, W.; Wilson, K.; Larsen, G. & Lopez, R.
Partner: UNT Libraries Government Documents Department
open access

Filter efficiency and pressure drop calculations through two and three dimensional fiber arrays

Description: We have used a commercially available fluid dynamics code, NEKTON version 2.85, and the Langevin particle equation of motion to compute the particle capture efficiency and pressure drop through selected two- and three-dimensional fiber arrays. The approach we used was to first compute the air velocity vector field throughout a defined region containing the fiber matrix. The particle capture in the fiber matrix is then computed by superimposing the Langevin particle equation of motion over the f… more
Date: April 1, 1994
Creator: Bergman, W.; Corey, I. & Speck, D.
Partner: UNT Libraries Government Documents Department
open access

The low-temperature specific heat of CeCu{sub 2}Ge{sub 2} at 0 and 9.5 kbar

Description: CeCu{sub 2}Ge{sub 2} orders antiferromagnetically, T{sub N} {approximately} 4K, and {gamma}(T) {approximately} 200 mJ/K{sup 2}{center_dot}mole near 0.5K and P = 0. A pressure of 9.5 kbar has no measurable effect on T{sub N}; reduces slightly the specific-heat anomaly at T{sub N}; and reduces slightly {gamma}(T) below 0.7K. These effects of pressure are in striking contrast to the much stronger effects on other heavy-fermion compounds, e.g., CeAl{sub 3}, URu{sub 2}Si{sub 2} and CeCu{sub 2}Si{sub… more
Date: April 1, 1993
Creator: Fisher, R. A.; Emerson, J. P.; Phillips, N. E.; Caspary, R. & Steglich, F.
Partner: UNT Libraries Government Documents Department
open access

Microfluidic Tools for Biological Sample Preparation

Description: Researchers at Lawrence Livermore National Laboratory are developing means to collect and identify fluid-based biological pathogens in the forms of proteins, viruses, and bacteria. To support detection instruments, we are developing a flexible fluidic sample preparation unit. The overall goal of this Microfluidic Module is to input a fluid sample, containing background particulates and potentially target compounds, and deliver a processed sample for detection. We are developing techniques for s… more
Date: April 10, 2002
Creator: Visuri, S R; Ness, K; Dzenitis, J; Benett, B; Bettencourt, K; Hamilton, J et al.
Partner: UNT Libraries Government Documents Department
open access

Fracture Permeability Evolution in Rock from the Desert Peak EGS Site

Description: Fluid flow experiments are being conducted on core specimens of quartz monzonite retrieved from depths of about 1 km at the Desert Peak East EGS site in Churchill County, Nevada. Our immediate goal is to observe permeability evolution in fractures at pressure and temperature conditions appropriate to the Desert Peak geothermal site. Longer term, we aim to evaluate mechanisms that control the evolution of fracture permeability. In the experiments saline water is flowed through an artificial frac… more
Date: April 8, 2004
Creator: Carlson, S. R.; Roberts, J. J.; Detwiler, R. L.; Burton, E. A.; Robertson-Tait, A.; Morris, C. et al.
Partner: UNT Libraries Government Documents Department
open access

Carbon Nanotube-Based Permeable Membranes

Description: A membrane of multiwalled carbon nanotubes embedded in a silicon nitride matrix was fabricated for use in studying fluid mechanics on the nanometer scale. Characterization by fluorescent tracer diffusion and scanning electron microscopy suggests that the membrane is void-free near the silicon substrate on which it rests, implying that the hollow core of the nanotube is the only conduction path for molecular transport. Assuming Knudsen diffusion through this nanotube membrane, a maximum helium t… more
Date: April 6, 2004
Creator: Holt, J K; Park, H G; Bakajin, O; Noy, A; Huser, T & Eaglesham, D
Partner: UNT Libraries Government Documents Department
open access

EPMT: a portable transfer standard for telemetry system pressure-transducer calibration

Description: The LLL developed electronic pressure meter (EPMT) is a portable static-pressure calibration instrument for use with the LLL telemetry transducer system at the Nevada Test Site (NTS). It is significantly more accurate and rugged than the bourdon-tube pressure gauge it replaces, and can be incorporated into a field-use, semi-automatic, pressure calibration system. The process by which a transducer is selected for EPMT use from the inventory of field-service-certified transducers and subjected to… more
Date: April 5, 1977
Creator: Hasbrouck, Richard T.
Partner: UNT Libraries Government Documents Department
open access

Airflow Simulations around OA Intake Louver with Electronic Velocity Sensors

Description: It is important to control outdoor airflow rates into HVAC systems in terms of energy conservation and healthy indoor environment. Technologies are being developed to measure outdoor air (OA) flow rates through OA intake louvers on a real time basis. The purpose of this paper is to investigate the airflow characteristics through an OA intake louver numerically in order to provide suggestions for sensor installations. Airflow patterns are simulated with and without electronic air velocity sensor… more
Date: April 1, 2009
Creator: Han, Hwataik; Sullivan, Douglas P. & Fisk, William J.
Partner: UNT Libraries Government Documents Department
open access

Numerical errors in the presence of steep topography: analysis and alternatives

Description: It is well known in computational fluid dynamics that grid quality affects the accuracy of numerical solutions. When assessing grid quality, properties such as aspect ratio, orthogonality of coordinate surfaces, and cell volume are considered. Mesoscale atmospheric models generally use terrain-following coordinates with large aspect ratios near the surface. As high resolution numerical simulations are increasingly used to study topographically forced flows, a high degree of non-orthogonality is… more
Date: April 15, 2010
Creator: Lundquist, K A; Chow, F K & Lundquist, J K
Partner: UNT Libraries Government Documents Department
open access

Acoustic emission experiments for safety of nuclear reactor vessels

Description: Acoustic emission monitoring was used in hydrostatic experiments on flawed pressure vessels and thermal shock experiments on flawed cylindrical specimens. The results of the experiments are discussed.
Date: April 26, 1976
Creator: Ying, S. P.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen