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Effect of the equilibrium magnetic field on plasma edge fluctuations

Description: The magnetic field structure reflected in the safety factor (q) profile can play an important role in defining some of the basic structures of the magnetohydrodynamic (MHD) turbulence: it plays a role in the generation of spatial structures in the initial nonlinear phase, and it gives a radial dependence to the spectral average of the square of the poloidal mode number, {l angle}m{sup 2}{r angle}{sup 1/2}, that can modify the explicit dependences of an analytically derived expression for turbulence-induced anomalous losses. 12 refs., 4 figs.
Date: January 1, 1990
Creator: Carreras, B.A.; Leboeuf, J.N.; Lee, D.K.; Holmes, J.A. & Lynch, V.E.
Partner: UNT Libraries Government Documents Department

Global climate change and effects on Pacific Northwest salmonids: An exploratory case study

Description: Recently, a number of papers have addressed global warming and freshwater fisheries. The recent report to Congress by the US Environmental Protection Agency included an analysis of potential effects of global warming on fisheries of the Great Lakes, California, and the Southeast. In California, the report stated that salinity increases in the San Francisco Bay could enhance the abundance of marine fish species, while anadromous species could be adversely affected. This paper discusses global climate changes and the effects on Pacific Northwest Salmonids. The impacts of climate change or Spring Chinook production in the Yakima Sub-basin was simulated using a computer modeling system developed for the Northwest Power planning council. 35 refs., 1 fig., 1 tab.
Date: September 1, 1990
Creator: Shankle, S.A.
Partner: UNT Libraries Government Documents Department

The ATF two-frequency correlation reflectometer

Description: The Advanced Toroidal Facility (ATF) density fluctuation reflectometer system consists of two individual reflectometers operating in the 30- to 40-GHz band. Each reflectometer consists of a tunable microwave source and a quadrature phase detector connected to the same antenna system. This arrangement allows two-frequency operation along the same radial chord for radial coherence measurements. The technique used in making radial coherence measurements is discussed and the results of such experiments are given. Initial experiments have shown high coherence when the frequencies of the two reflectometers are tuned close together and a clear loss of coherence as the radial separation of the cutoff layers is increased by increasing the frequency separation of the two reflectometers. Recent results have shown that local measurements of density fluctuations in plasmas with electron cyclotron heating (ECH) are possible and that detailed structure can be seen in the fluctuation spectra. In addition, radial correlation lengths have been found to be from 0.5 to 1.0 cm in ECH plasmas, with some frequency structures having correlation lengths up to 3 cm. In plasmas with neutral beam injection (NBI), the radial correlation lengths in the edge region have been found to be approximately 0.1--0.2 cm. 4 figs.
Date: January 1, 1990
Creator: Hanson, G. R.; Wilgen, J. B.; Anabitarte, E.; Bell, J. D.; Harris, J. H.; Dunlap, J. L. et al.
Partner: UNT Libraries Government Documents Department

Comparison between CMPO and DHDECMP for alpha decontamination of radioactive liquid waste

Description: Ion exchange is the major method used at Los Alamos to recover and purify plutonium from a variety of different contaminants. During this process, a high-acid (5-7M), low-activity stream is produced that presently is concentrated by evaporation, then cemented for long-term disposal. Our goal is to remove and concentrate the radioactive elements so that the remainder can be treated as low-level'' or regular industrial waste. Solvent extraction with neutral bifunctional extractants, such as DHDECMP and CMPO, has been chosen as the process to be developed. Experimental work has shown that both extractants effectively remove actinides to below the required limits, but that CMPO was much more difficult to strip. In addition, studies of plutonium and americium removal using a wide variety of ion exchangers and supported extractants including DHDECMP, CMPO, and TOPO will be reviewed. 22 refs., 10 figs., 3 tabs.
Date: January 1, 1990
Creator: Muscatello, A. C.; Yarbro, S .L. & Marsh, S. F.
Partner: UNT Libraries Government Documents Department

Edge turbulence and transport: Text and ATF modeling

Description: We present experimental results on edge turbulence and transport from the tokamak TEXT and the torsatron ATF. The measured electrostatic fluctuations can explain the edge transport of particles and energy. Certain drive (radiation) and stabilizing (velocity shear) terms are suggested by the results. The experimental fluctuation levels and spectral widths can be reproduced by considering the nonlinear evolution of the reduced MHD equations, incorporating a thermal drive from line radiation. In the tokamak limit (with toroidal electric field) the model corresponds to the resistivity gradient mode, while in the currentless torsatron or stellarator limit it corresponds to a thermally driven drift wave.
Date: January 1, 1990
Creator: Ritz, C.P.; Rhodes, T.L.; Lin, H.; Rowan, W.L.; Bengtson, R.; Wootton, A.J. (Texas Univ., Austin, TX (USA). Fusion Research Center) et al.
Partner: UNT Libraries Government Documents Department

An evaluation of three models designed for siting wind turbines in areas of complex terrain

Description: The aim of this study was to compare the ability of three micrositing models to simulate the wind flow in complex terrain. One of these models, NOABL, is a mass-consistent model while the other two, MS3DJH/3R and BZ, are descendants of Jackson-Hunt (J-H) theory. All three models were applied to two areas of complex terrain, Askervein Hill in Scotland and Altamont Pass in California. Askervein Hill is an isolated hill of moderate slope surrounded by a flat plain. In marked contrast, the terrain of Altamont Pass is very complicated and is aptly described as being very hilly. Over each modeled area, wind measurements taken from a relatively dense network of anemometry were used to assess the performance of the models by comparing these data to the model-derived winds. 20 refs., 13 figs., 7 tabs.
Date: June 1, 1990
Creator: Barnard, J.C.
Partner: UNT Libraries Government Documents Department

Climatological summary of wind and temperature data for the Hanford Meteorology Monitoring Network

Description: This document presents climatological summaries of wind and temperature data collected at the twenty-five monitoring stations operated by the Hanford Meteorology Monitoring Network. The climatological analyses presented here involve hourly averaged wind data collected over an 8-year period beginning in 1982 (fewer wind data are available for the several monitoring stations that began full-time operation after 1982) and hourly averaged air temperature data collected over 2-year period beginning in mid-1988. The tables and figures presented in this document illustrate the spatial and temporal variation of meteorological parameters across the Hanford Site and the surrounding areas. This information is useful for emergency response applications, routine meteorological forecasting, planning and scheduling operations, facility design, and environmental impact studies.
Date: September 1, 1990
Creator: Glantz, C.S.; Schwartz, M.N.; Burk, K.W.; Kasper, R.B.; Ligotke, M.W. & Perrault, P.J.
Partner: UNT Libraries Government Documents Department

Simulation of seasonal cloud forcing anomalies

Description: One useful way to classify clouds is according to the processes that generate them. There are three main cloud-formation agencies: deep convection; surface evaporation; large-scale lifting in the absence of conditional instability. Although traditionally clouds have been viewed as influencing the atmospheric general circulation primarily through the release of latent heat, the atmospheric science literature contains abundant evidence that, in reality, clouds influence the general circulation through four more or less equally important effects: interactions with the solar and terrestrial radiation fields; condensation and evaporation; precipitation; small-scale circulations within the atmosphere. The most advanced of the current generation of GCMs include parameterizations of all four effects. Until recently there has been lingering skepticism, in the general circulation modeling community, that the radiative effects of clouds significantly influence the atmospheric general circulation. GCMs have provided the proof that the radiative effects of clouds are important for the general circulation of the atmosphere. An important concept in analysis of the effects of clouds on climate is the cloud radiative forcing (CRF), which is defined as the difference between the radiative flux which actually occurs in the presence of clouds, and that which would occur if the clouds were removed but the atmospheric state were otherwise unchanged. We also use the term CRF to denote warming or cooling tendencies due to cloud-radiation interactions. Cloud feedback is the change in CRF that accompanies a climate change. The present study concentrates on the planetary CRF and its response to external forcing, i.e. seasonal change.
Date: August 1, 1990
Creator: Randall, D. A.
Partner: UNT Libraries Government Documents Department

Robustness of a multiple-use reservoir to seasonal runoff shifts associated with climate change

Description: Although much remains to be learned about long-term climate change associated with anthropogenic increases in concentrations of the so-called greenhouse gases,'' such as carbon dioxide and methane, there is a general consensus that some global warming will result from past and present emissions. In the western United States, the dominant hydrologic effect of such warming, aside from any accompanying changes in precipitation, would be to reduce winter snow accumulations in mountainous headwaters regions. To assess the robustness of reservoir operation to such shifts in seasonal runoff, simulations were developed of monthly runoff for the American River, Washington, using the National Weather Service River Forecast System. The American River is presently unregulated; however, we tested the performance of hypothetical reservoirs with capacity of 0.25 and 0.50 of the mean annual flow for a range of annual temperature changes from 0.0 (present climate) to 4.0{degree}C. We considered a multiple-purpose reservoir system operated for water supply ad hydropower, with minimum releases required for fisheries enhancement. In addition to evaluating the sensitivity of water supply, low flow, and hydropower performance using a heuristic operating rule, the relative performance of the system under present and altered climates was evaluated using an optimization algorithm, extended linear quadratic Gaussian control. This paper reports the results of hydrologic simulations for the American River, Washington. 13 refs., 8 figs.
Date: May 1, 1990
Creator: Lettenmaier, D.P.; Brettman, K.L. (Washington Univ., Seattle, WA (USA). Dept. of Civil Engineering) & Vail, L.W. (Pacific Northwest Lab., Richland, WA (USA))
Partner: UNT Libraries Government Documents Department

Empirical estimates of the proton-neutron interaction and diabolical points

Description: The use of constant-N contours in the ({omega},{lambda}) plane is demonstrated both for establishing diabolical points and for studying regularities and fluctuations in the spectrum of single-particle states. Likewise the average properties and fluctuations of empirical proton-neutron interactions, obtained from double differentials of the total energy with respect to N and Z, are discussed for the ground states of all even-even nuclei with N > 40 and as a function of the rotational frequency for the lowest even-spin, positive-parity decay sequence of deformed rare earth nuclei. 25 refs., 3 figs.
Date: January 1, 1990
Creator: Zhang, J.-Y. (Academia Sinica, Beijing, BJ (China). Inst. of Theoretical Physics Brookhaven National Lab., Upton, NY (USA) Joint Inst. for Heavy Ion Research, Oak Ridge, TN (USA) Academia Sinica, Lanzhou, GS (China). Inst. of Modern Physics); Garrett, J.D. (Oak Ridge National Lab., TN (USA)); Casten, R.F. (Brookhaven National Lab., Upton, NY (USA)) & Brenner, D.S. (Clark Univ., Worcester, MA (USA)
Partner: UNT Libraries Government Documents Department

Confinement studies in the ZT-40M reversed field pinch

Description: Measurement of electrostatic and magnetic fluctuations in the ZT-40M Reversed Field Pinch (RFP) are used to estimate fluctuation driven transport. Edge electrostatic fluctuations appear to explain edge particle transport, analogously to some tokamak and stellarator observations. However, in contrast to tokamaks, electrostatic fluctuations do not explain the heat flux through the edge. Instead, transport of suprathermal electrons along fluctuating magnetic field lines constitute the major electron heat loss. Ion losses in ZT-40M appear to be dominated by charge exchange.
Date: January 1, 1990
Creator: Weber, P.G.; Schoenberg, K.F.; Ingraham, J.C.; Miller, G.; Moses, R.W.; Munson, C.P. et al.
Partner: UNT Libraries Government Documents Department

A comparison of two- and three-dimensional S809 airfoil properties for rough and smooth HAWT (horizontal-axis wind turbine) rotor operation

Description: At the Solar Energy Research Institute (SERI), we carried out tests to measure the effects of leading-edge roughness on an S809 airfoil using a 10-m, three-bladed, horizontal-axis wind turbine (HAWT). The rotor employed a constant-chord (.457 m) blade geometry with zero twist. Blade structural loads were measured with strain gages mounted at 9 spanwise locations. Airfoil pressure measurements were taken at the 80% spanwise station using 32 pressure taps distributed around the airfoil surface. Detailed inflow measurements were taken using nine R.M. Young Model 8002 propvane anemometers on a vertical plane array (VPA) located 10 m upwind of the test turbine in the prevailing wind direction. The major objective of this test was to determine the sensitivity of the S809 airfoil to roughness on a rotating wind turbine blade. We examined this effect by comparing several parameters. We compared power curves to show the sensitivity of whole rotor performance to roughness. We used pressure measurements to generate pressure distributions at the 80% span which operates at a Reynolds number (Re) of 800,000. We then integrated these distributions to determine the effect of roughness on the section's lift and pressure-drag coefficients. We also used the shapes of these distributions to understand how roughness affects the aerodynamic forces on the airfoil. We also compared rough and smooth wind tunnel data to the rotating blade data to study the effects of blade rotation on the aerodynamic behavior of the airfoil below, near, and beyond stall. 13 refs., 11 figs.
Date: February 1, 1990
Creator: Musial, W. D.; Butterfield, C. P. & Jenks, M. D.
Partner: UNT Libraries Government Documents Department

Solar variations and their influence on trends in upper stratospheric ozone and temperature

Description: Over the past decade, knowledge of the magnitude and temporal structure of the variations in the sun's ultraviolet irradiance has increased steadily. A number of theoretical modeling studies have shown that changes in the solar ultraviolet flux during the 11-year solar cycle can have a significant effect on stratospheric ozone concentrations. With the exception of Brasseur et al., who examined a very broad range of solar flux variations, all of these studies assumed much larger changes in the ultraviolet flux than measurements now indicate. These studies either calculated the steady-state effect at solar maximum and solar minimum or assumed sinusoidal variations in the solar flux changes with time. It is now possible to narrow the uncertainty range of the expected effects on upper stratospheric ozone and temperature resulting from the 11-year solar cycle. A more accurate representation of the solar flux changes with time is used in this analysis, as compared to previous published studies. This study also evaluates the relative roles of solar flux variations and increasing concentrations of long-lived trace gases in determining the observed trends in upper stratospheric ozone and temperature. The LLNL two-dimensional chemical-radiative-transport model of the global atmosphere is used to evaluate the combined effects on the stratosphere from changes in solar ultraviolet irradiances and trace gas concentrations over the last several decades. Derived trends in upper stratospheric ozone concentrations and temperature are then compared with available analyses of ground-based and satellite measurements over this time period.
Date: October 1, 1990
Creator: Wuebbles, D.J.; Kinnison, D.E. (Lawrence Livermore National Lab., CA (USA)) & Lean, J.L. (Naval Research Lab., Washington, DC (USA). E.O. Hulburt Center for Space Research)
Partner: UNT Libraries Government Documents Department

Scattering by anisotropic grains in beryllium mirrors

Description: Scattering from mirror surfaces arises from topographic and non-topographic sources. This paper considers the nontopographic scattering of beryllium mirrors modelled as a collection of randomly oriented bireflective grains. Simple scattering theory shows that this type of scatting scales as {lambda}{sup {minus}2}, rather than as {lambda}{sup {minus}4} for topographic scattering, which means that it is relatively more important at long radiation wavelengths. Estimates of the intensity based an available short-wavelength values of the anisotropic optical constants of beryllium indicate that this type of scattering could dominate the topographic scattering from smooth surfaces at CO{sub 2} wavelengths. 10 refs., 2 figs.
Date: August 1, 1990
Creator: Church, E.L. (Army Armament Research and Development Command, Dover, NJ (USA)); Takacs, P.Z. (Brookhaven National Lab., Upton, NY (USA)) & Stover, J.C. (TMA Technologies, Inc., Bozeman, MT (USA))
Partner: UNT Libraries Government Documents Department

Seismic fragility of nuclear power plant components (Phase II)

Description: As part of the Component Fragility Program which was initiated in FY 1985, three additional equipment classes have been evaluated. This report contains the fragility results and discussions on these equipment classes which are switchgear, I and C panels and relays. Both low and medium voltage switchgear assemblies have been considered and a separate fragility estimate for each type is provided. Test data on cabinets from the nuclear instrumentation/neutron monitoring system, plant/process protection system, solid state protective system and engineered safeguards test system comprise the BNL data base for I and C panels (NSSS). Fragility levels have been determined for various failure modes of switchgear and I C panels, and the deterministic results are presented in terms of test response spectra. In addition, the test data have been evaluated for estimating the respective probabilistic fragility levels which are expressed in terms of a median value, an uncertainty coefficient, a randomness coefficient and an HCLPF value. Due to a wide variation of relay design and the fragility level, a generic fragility level cannot be established for relays. 7 refs., 13 figs., 12 tabs.
Date: February 1, 1990
Creator: Bandyopadhyay, K. K.; Hofmayer, C. H.; Kassir, M. K. & Pepper, S. E. (Brookhaven National Lab., Upton, NY (USA))
Partner: UNT Libraries Government Documents Department

Causes of failing the draft ANSI Standard N13. 30 radiobioassay performance criterion for minimum detectable amount

Description: The test methods used for PNL bioassay performance tests were evaluated by comparing the MDA based on performance tests results with MDA calculated by PNL using the bioassay laboratory's own quality control (QC) data. Two in vitro laboratories and two in vivo laboratories were studied and a correlation between the performance test MDA estimates and QC data was demonstrated. However, it was often necessary to examine the QC data to identify important characteristics of the blank distribution that affect the MDA calculation. Since the MDA equation must be based on the specific analysis and calculational methods of the procedure evaluated. Even when the correct MDA equation is applied, the MDA calculated will have a relatively large confidence interval when only a few replicates are used to estimate the standard deviation. For this reason, a relatively precise estimate of the MDA is generally only available when Poisson statistics may be applied. It was concluded that performance testing alone cannot provide all the information necessary to make an accurate estimate of the measurement process MDA. Review of the laboratory's QC data and the entire measurement procedure will be necessary. Specific recommendations for changes to draft ANSI N13.30 Performance Criteria for Radiobioassay'' are given. 10 refs., 18 figs., 11 tabs.
Date: February 1, 1990
Creator: MacLellan, J.A.
Partner: UNT Libraries Government Documents Department

Turbulence in slurry pipe flow

Description: The present state of knowledge of liquid-solid flows (slurries) is far behind than that for single phase flows. Very few geometries have been examined with a slurry and only with a limited variation of system parameters i.e. fluid viscosity, particle diameter, etc. This paper presents the first part of a study which examines the effects of the addition of a solid to the flow through a confined coaxial jet. Presented here will be the initial conditions for the jet which correspond to fully developed pipe flow. 6 refs., 9 figs.
Date: January 1, 1990
Creator: Gore, R.A. (Los Alamos National Lab., NM (USA)) & Crowe, C.T. (Washington State Univ., Pullman, WA (USA). Dept. of Mechanical and Materials Engineering)
Partner: UNT Libraries Government Documents Department

Water-table elevations on the Hanford Site, December 1989

Description: The Site Characterization and Assessment Section, Environmental Sciences Department, of the Pacific Northwest Laboratory (PNL) prepares water-table maps of the Hanford Site in southeastern Washington. Water levels in selected wells open to the unconfined aquifer on the Hanford Site are measured in June and December of each year. The purpose of these measurements is to determine the changes in the configuration of the water table to assess the physical impact of waste disposal on ground-water flow. Water-level measurements can be used to construct a water-table map that represents the elevation of the water-table surface. These maps can be used to infer general directions of ground-water flow, particularly in the upper part of the aquifer. In addition to water levels measured across the Hanford Site, water levels were also measured from four specific areas within Hanford. Included are areas around the decommissioned 216-U-10 Pond (U Pond), the 216-B-3 Pond (B-Pond), the 100-N Area and the 300 Area. 17 refs., 4 figs.
Date: June 1, 1990
Creator: Newcomer, D.R. & McDonald, J.P.
Partner: UNT Libraries Government Documents Department

Experimental observations on transition to turbulence in confined coaxial jets and other boundary layer flows

Description: Experiments performed demonstrate the transition to turbulent flow of water jets discharging coaxially into a stream confined in a round duct. The critical Reynolds number is shown to be a strong function of velocity ratio. From the flow visualization it is shown that a proportionality between the laminar length of the jet (L) and the wavelength ({lambda}) can be seen in the region of transition to turbulence. The proportionality coincides with similar observations concerning the transition to turbulence in various other flows. A brief argument based on scale analysis is presented for the confined coaxial jet and round plume. The apparent universality of the L/{lambda} {approximately} O(10) scaling law supports the conclusion that the laminar sections of all naturally progressing boundary layer-type flows are geometrically similar. 21 refs., 8 figs.
Date: January 1, 1990
Creator: Gore, R.A. (Los Alamos National Lab., NM (USA)); Crowe, C.T. (Washington State Univ., Pullman, WA (USA). Dept. of Mechanical and Materials Engineering) & Bejan, A. (Duke Univ., Durham, NC (USA). Dept. of Mechanical Engineering and Materials Science)
Partner: UNT Libraries Government Documents Department

Energy's role in competitiveness: Context and strategy

Description: This study of competitiveness has three objectives. The first objective is to explain how macroeconomic and microeconomic factors can affect structural change in the US economy and how energy is linked to these factors. The second objective is to provide an explanation of how many individual decision makers, in responding to higher energy prices, have changed the structure of the economy. This structural change, and the effect it has had on energy use, is estimated for the US economy. A major component of these changes results from changes in US trade with other countries, which gives rise to the third objective. The third objective is to develop a research design that will allow a better understanding of the role that energy plays in the competitiveness of goods in world trade. 30 refs., 11 figs., 5 tabs.
Date: February 1, 1990
Creator: Roop, J.M.
Partner: UNT Libraries Government Documents Department

Evaluation of Hanford site water-table changes, 1980--1990

Description: Irrigation applied west of the Hanford Site and wastewater management practices on the Hanford Site resulted in significant changes in the configuration of the water table between December 1979 and December 1989. In the Cold Creek Valley, located in the western part of the Hanford Site, the water table rose more than 3 m (9 ft) between December 1979 and December 1989. Since 1969, the water table in the Cold Creek Valley has been rising, primarily in response to irrigation practices in the Upper Cold Creek Valley. The largest areal changes have occurred in the vicinity of production facilities in the 200 Areas where ground-water mounds have developed since operations began in 1943. During the 1940s and 1950s, two ground-water mounds developed as a result of wastewater management practices in the 200 Areas, one beneath 216-U-10 Pond in the 200-West Area and one beneath 216-B-3 Pond near the 200-East Area. During the 1960s, the ground-water mounds grew moderately before reaching near-equilibrium conditions during the 1970s. During the 1980s (December 1979 to December 1989), stresses imposed on the unconfined aquifer caused recurrence of unsteady state conditions. In the 200-West Area, the water level declined more than 2.5 m (8 ft) between December 1979 and 1989. Most of the decline occurred after 1984, which correlates with a reduction in wastewater discharge caused by the decommissioning of 216-U-10 Pond in 1984. The decline in the water table occurred mostly in the area between the 200-West Area and the Yakima Ridge basalt, which outcrops above the water table to the south of the 200-West Area. 50 refs., 31 figs., 1 tab.
Date: November 1, 1990
Creator: Newcomer, D.R.
Partner: UNT Libraries Government Documents Department

Concepts in strong Langmuir turbulence theory

Description: Some of the basic concepts of strong Langmuir turbulence (SLT) theory are reviewed. In SLT system, a major fraction of the turbulent energy is carried by local, time-dependent, nonlinear excitations called cavitons. Modulational instability, localization of Langmuir fields by density fluctuations, caviton nucleation, collapse, and burnout and caviton correlations are reviewed. Recent experimental evidence will be presented for SLT phenomena in the interaction of powerful HF waves with the ionosphere and in laser-plasma interaction experiments. 38 refs., 11 figs.
Date: January 1, 1990
Creator: DuBois, D.F. & Rose, H.A.
Partner: UNT Libraries Government Documents Department

Aperiodicity in one-dimensional cellular automata

Description: Cellular automata are a class of mathematical systems characterized by discreteness (in space, time, and state values), determinism, and local interaction. A certain class of one-dimensional, binary site-valued, nearest-neighbor automata is shown to generate infinitely many aperiodic temporal sequences from arbitrary finite initial conditions on an infinite lattice. The class of automaton rules that generate aperiodic temporal sequences are characterized by a particular form of injectivity in their interaction rules. Included are the nontrivial linear'' automaton rules (that is, rules for which the superposition principle holds); certain nonlinear automata that retain injectivity properties similar to those of linear automata; and a wider subset of nonlinear automata whose interaction rules satisfy a weaker form of injectivity together with certain symmetry conditions. A technique is outlined here that maps this last set of automata onto a linear automaton, and thereby establishes the aperiodicity of their temporal sequences. 12 refs., 3 figs.
Date: January 1, 1990
Creator: Jen, E.
Partner: UNT Libraries Government Documents Department