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3-D turbulent particle dispersion submodel development. Quarterly progress report No. 1, 5 April--5 July 1991

Description: The lack of a mathematical description of the interactions of fluid turbulence with other physics-chemical processes is a major obstacle in modeling many industrial program. Turbulent two-phase flow is a phenomenon that is of significant practical importance to coal combustion as well as other disciplines. The interactions of fluid turbulence with the particulate phase has yet to be accurately and efficiently modeled for these industrial applications. On 15 May 1991 work was initiated to cover four major tasks toward the development of a computational submodel for turbulent particle dispersion that would be applicable to coal combustion simulations. Those four tasks are: 1. A critical evaluation of the 2-D Lagrangian particle dispersion submodel, 2. Development of a 3-D submodel for turbulent particle dispersion, 3. Evaluation of the 3-D submodel for turbulent particle dispersion, 4.Exploration of extensions of the Lagrangian dispersion theory to other applications including chemistry-turbulence interactions.
Date: December 31, 1991
Creator: Smith, P. J.
Partner: UNT Libraries Government Documents Department

3-D turbulent particle dispersion submodel development. Quarterly progress report No. 2, 15 July--15 October 1991

Description: The lack of a mathematical description of the interactions of fluid turbulence with other physics-chemical processes is a major obstacle in modeling many industrial program. Turbulent two-phase flow is a phenomenon that is of significant practical importance to coal combustion as well as other disciplines. The interactions of fluid turbulence with the particulate phase has yet to be accurately and efficiently modeled for these industrial applications. On 15 May 1991 work was initiated to cover four major tasks toward the development of a computational submodel for turbulent particle dispersion that would be applicable to coal combustion simulations. Those four tasks are: 1. A critical evaluation of the 2-D Lagrangian particle dispersion submodel, 2. Development of a 3-D submodel for turbulent particle dispersion, 3. Evaluation of the 3-D submodel for turbulent particle dispersion, 4. Exploration of extensions of the Lagrangian dispersion theory to other applications including chemistry-turbulence interactions.
Date: December 31, 1991
Creator: Smith, P. J.
Partner: UNT Libraries Government Documents Department

40-{angstrom} FEL designs for the PEP storage ring

Description: We explore the use of the 2.2-km PEP storage ring at SLAC to drive a 40-{Angstrom} free-electron laser in the self-amplified spontaneous emission configuration. Various combinations for electron-beam and undulator parameters, as well as special undulator designs, are discussed. Saturation and high peak, in-band, coherent power (460 MW) are possible with a 67-m, hybrid permanent-magnet undulator in a ring bypass. A 100-m, cusp-field undulator can achieve high average, in-band, coherent power (0.25 W) in the main ring. The existing, 25.6-m, Paladin undulator at LLNL, with the addition of optical-klystron dispersive sections, is considered for both peak and average power. 35 refs., 4 figs., 1 tab.
Date: December 31, 1991
Creator: Fisher, A. S.; Gallardo, J. C.; Nuhn, H. D.; Tatchyn, R.; Winick, H. & Pellegrini, C.
Partner: UNT Libraries Government Documents Department

180 MW demonstration of advanced tangentially-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Technical progress report second quarter, 1991

Description: ABB CE`s Low NOx Bulk Furnace Staging (LNBFS) System and Low NOx Concentric Firing System (LNCFS) are demonstrated in stepwise fashion. These systems incorporate the concept of advanced overfire air (AOFA), clustered coal nozzles, and offset air. A complete description of the installed technologies is provided in the following section. The primary objective of the Plant Lansing Smith demonstration is to determine the long-term effects of commercially available tangentially-fired low NOx combustion technologies on NOx emissions and boiler performance. Short-term tests of each technology are also being performed to provide engineering information about emissions and performance trends. A target of achieving fifty percent NOx reduction using combustion modifications has been established for the project.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

1990 results with polarized protons and antiprotons (E704)

Description: The results from the highest-energy polarized proton and antiproton beam, available as of January 1991, can be summarized as follows: The single-spin results for {pi}{sub o} production at x{sub F} {approx} 0 and x{sub t} = 0.4 are important not only because the spin effect is large and exhibits x{sub t}-scaling, but also because transverse-spin effects in general present a particular challenge for the theoretical interpretation. This contrasts with longitudinal spin effects which can be related to parton helicities. The measurements of neutral and charged pion production by protons and antiprotons at pion transverse momenta of p{sub t} < 2 GeV/c represent an extensive set of high-energy data that will provide a complete, clear picture of the experimental situation in ``soft`` pion production at 200 GeV. The measurement of the two-spin parameter A{sub LL} has not reached the statistical precision and the highest p{sub t}-values attainable at Fermilab. This parameter is of particular interest because, in hadronic reactions that are dominated by parton-parton scattering, A{sub LL} is related to the spin properties of the parton scattering amplitudes and to the spin-weighted parton helicity distributions. This results are discussed farther in this report.
Date: December 31, 1991
Creator: E581/704 Collaboration
Partner: UNT Libraries Government Documents Department

1991 Annual report on scientific programs: A broad research program on the sciences of complexity

Description: 1991 was continued rapid growth for the Santa Fe Institute (SFI) as it broadened its interdisciplinary research into the organization, evolution and operation of complex systems and sought deeply the principles underlying their dynamic behavior. Research on complex systems--the focus of work at SFI--involves an extraordinary range of topics normally studied in seemingly disparate fields. Natural systems displaying complex behavior range upwards from proteins and DNA through cells and evolutionary systems to human societies. Research models exhibiting complexity include nonlinear equations, spin glasses, cellular automata, genetic algorithms, classifier systems, and an array of other computational models. Some of the major questions facing complex systems researchers are: (1) explaining how complexity arises from the nonlinear interaction of simples components, (2) describing the mechanisms underlying high-level aggregate behavior of complex systems (such as the overt behavior of an organism, the flow of energy in an ecology, the GNP of an economy), and (3) creating a theoretical framework to enable predictions about the likely behavior of such systems in various conditions. The importance of understanding such systems in enormous: many of the most serious challenges facing humanity--e.g., environmental sustainability, economic stability, the control of disease--as well as many of the hardest scientific questions--e.g., protein folding, the distinction between self and non-self in the immune system, the nature of intelligence, the origin of life--require deep understanding of complex systems.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

1991 Technical progress report of the University of South Carolina`s High Energy Physics Group, February 1990--July 1991

Description: The high energy physics group at the University of South Carolina includes five teaching faculty members, one research faculty member, and five graduate students. Profs. Childers, Darden, and Wilson devote most of their research effort to Fermilab experiment E789, which is designed to observe charmless two-body decays of b-flavored mesons and baryons. Prof. Wilson works on Fermilab experiment E687 which studies charm physics in the wide-band photon beam. Profs. Rosenfeld and Wang participate in the AMY collaboration, which studies electron-positron interactions using the TRISTAN collider at KEK. Prof. Rosenfeld and one student collaborate with personnel from KEK and INS, Tokyo, on an experiment to detect a 17 keV neutrino in the {beta}-decay spectrum of {sup 63}Ni. Members of the group also participate in Fermilab Proposal P803 which will search for the oscillation of muon neutrino to tau neutrino with sensitivity better than a factor of 40 than previously achieved and in Superconducting Super Collider activities which include the development of an imaging preradiator. A brief discussion is given on progress made for each program.
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Ac losses in YBa{sub 2}Cu{sub 3}O{sub 7} and Bi{sub 2}Sr{sub 2}Ca{sub 2}Ci{sub 3}O{sub 10} superconductors at power frequencies

Description: Ac losses of sintered and melt-textured YBa{sub 2}Cu{sub 3}O{sub 7} bars and powder-in-a-tube processed Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} tapes were measured at 4.2, 65, 70 and 77 K and at 15--180 Hz. In general, the results are well described by the critical state model for the ac losses. However, the losses for the Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} tapes at 4.2 K exhibited significant contributions from the eddy currents in the Ag sheath.
Date: December 31, 1991
Creator: Orehotsky, J.; Reilly, K. M.; Suenaga, M.; Hikata, T.; Ueyama, M. & Sato, K.
Partner: UNT Libraries Government Documents Department

Accelerator Physics and Modeling: Proceedings

Description: This report contains papers on the following topics: Physics of high brightness beams; radio frequency beam conditioner for fast-wave free-electron generators of coherent radiation; wake-field and space-charge effects on high brightness beams. Calculations and measured results for BNL-ATF; non-linear orbit theory and accelerator design; general problems of modeling for accelerators; development and application of dispersive soft ferrite models for time-domain simulation; and bunch lengthening in the SLC damping rings.
Date: December 31, 1991
Creator: Parsa, Zoreh
Partner: UNT Libraries Government Documents Department

Accelerator research studies. Final report, June 1, 1990--November 30, 1991

Description: The program consisted of the following three tasks: TASK A, ``Study of Transport and Longitudinal Compression of Intense, High-Brightness Beams,`` TASK B, ``Study of Collective Ion Acceleration by Intense Electron Beams and Pseudospark Produced High Brightness Electron Beams,`` and TASK C, ``Study of a Gyroklystron High-Power Microwave Source for Linear Colliders.``
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Acceptance criteria for heat exchanger head staybolts

Description: Each of the six primary coolant loop systems of the Savannah River Site production reactors contains two parallel single-pass heat exchangers to transfer heat from the primary coolant (D{sub 2}O) to the secondary cooling water (H{sub 2}O). The configuration of the heat exchangers includes a plenary space defined by the heat exchanger tubesheet and the heat exchanger head at both the heat exchanger inlet and outlet to the primary piping. The primary restraint of the heat exchanger head (Type 304 stainless steel) is provided by 84 staybolts (Type 303 stainless steel) which attach to the tubesheet. The staybolts were cap seal-welded in the mid-1960`s and are immersed in moderator. Access to inspect the staybolts is limited to a recently-developed ultrasonic technique shooting a beam through the staybolt assembly. Acceptance Criteria to allow disposition of flaws detected by UT inspection have been developed. The structural adequacy to protect against collapse loading of the head is demonstrated by finite element analysis of the head assembly and fracture analysis of flaw postulates in the staybolts. Both normal operation and normal operation plus seismic loading conditions were considered. Several bounding cases containing various configurations of nonactive (exceeding critical flaw size) staybolts were analyzed. The model of the head assembly can be applied to evaluate any active staybolt configurations based on the results from future inspections. 9 refs.
Date: December 31, 1991
Creator: Sindelar, R. L.; Lam, P. S.; Barnes, D. M.; Placr, A. & Morrison, J. M.
Partner: UNT Libraries Government Documents Department

The acid precipitation provisions of the 1990 Clean Air Act Amendments and minorities` energy consumption

Description: In November 1990 Congress passed a comprehensive set of amendments to the Clean Air Act of 1977 with potentially very high compliance costs. The provisions pertaining to control of acid precipitation have been specified with sufficient detail to examine their cost impacts. These provisions will require investment in emissions control technology, mainly by electric utilities. Production costs will increase due to the required investment, resulting in higher electricity prices. This paper examines the possible magnitude of these effects and whether there might be differential impacts on racial/ethnic minority groups. Differential impacts were considered a possibility because of the differences in the percentage of total income spent on energy by various population subgroups. In 1989, the Majority group (defined as non-Black, non-Hispanic) spent about three percent of household income on energy, while Blacks spent double that, six percent, and Hispanics spent about four percent. (The differences in income underlying these figures are greater, however, than the differences in energy expenditures). To address these issues, we compare projected electricity consumption and expenditures and total energy expenditures for Black, Hispanic, and Majority households. The distribution of benefits from reducing acid precipitation is not addressed since the possible effects on ambient air quality in specific geographical areas that are directly attributable to reducing utilities` sulfur dioxide emissions are highly uncertain.
Date: December 31, 1991
Creator: Nieves, L. A. & Wernette, D.
Partner: UNT Libraries Government Documents Department

Activated sludge studies of selected contaminants of PFH wastewater

Description: Acetone, propionitrile, pyrrole, and thiocyanate were selected as representative compounds of wastewater expected from pressurized, fluidized-bed hydroretorting (PFH) of Eastern oil shales. The PFH process has been the subject of investigation by the Institute of Gas Technology, under contract with the United States Department of Energy, for the purpose of obtaining higher oil yields from Eastern shales than has been possible using conventional retorting methods. Preliminary batch experiments illustrated that acetone, propionitrile, pyrrole, and thiocyanate are aerobically biodegradable by heterogeneous microbiological cultures. Three continuous flow activated sludge reactors were used to further evaluate the biological treatability of the synthetic waste. The studies revealed that the compounds could be removed at hydraulic residence times of as low as one day. Three one-day experiments demonstrated that biological system`s capability to accept organic shock loadings without a change in effluent quality. A no-recycle reactor illustrated that the flocculent microbiological population had a high resistance to solids washout. Because a supplementary nitrogen source was not included in synthetic waste treated by the no-recycle unit, it was shown that propionitrile, pyrrole, and/or thiocyanate supplied the nitrogen necessary for biological activity.
Date: December 31, 1991
Creator: Dudley, S. K.; Bustamante, R. B. & Bonner, W. P.
Partner: UNT Libraries Government Documents Department

Activation analyses for different fusion structural alloys

Description: The leading candidate structural materials, viz., the vanadium alloys, the nickel or the manganese stabilized austenitic steels, and the ferritic steels, are analysed in terms of their induced activation in the TPSS fusion power reactor. The TPSS reactor has 1950 MW fusion power and inboard and outboard average neutron wall loading of 3.75 and 5.35 MW/m{sup 2} respectively. The results shows that, after one year of continuous operation, the vanadium alloys have the least radioactivity at reactor shutdown. The maximum difference between the induced radioactivity in the vanadium alloys and in the other iron-based alloys occurs at about 10 years after reactor shutdown. At this time, the total reactor radioactivity, using the vanadium alloys, is about two orders of magnitude less than the total reactor radioactivity utilizing any other alloy. The difference is even larger in the first wall, the FW-vanadium activation is 3 orders of magnitude less than other alloys` FW activation. 2 refs., 7 figs.
Date: December 31, 1991
Creator: Attaya, H. & Smith, D.
Partner: UNT Libraries Government Documents Department

Active and passive calcium transport systems in plant cells. Progress report, May 1986--January 1991

Description: The ability to change cytoplasmic Ca{sup 2+} levels ([Ca{sup 2+}]) by cells has made this cation a key regulator of many biological processes. Cytoplasmic [Ca{sup 2+}] is determined by the coordination of passive Ca{sup 2+} fluxes which increase cytosolic [Ca{sup 2+}] and active Ca{sup 2+} transport systems that lower cytosolic [Ca{sup 2+}]. The mechanisms by which plant cells achieve this is poorly understood. We have initially used isolated vesicles from the plasma membrane or organellar membranes to study Ca{sup 2+} transport systems in oat roots (a monocot) and carrot suspension cells (a dicot). The objectives of the proposal were to identify and characterize active (energy-dependent) and passive calcium transport systems that work together to regulate calcium levels in the cytoplasm of plant cells.
Date: December 31, 1991
Creator: Sze, H.
Partner: UNT Libraries Government Documents Department

Active two phase cooling of optics. Final technical report, January 22, 1988--July 22, 1991

Description: Two phase cooling of a higher powered laser optics offers a significant potential to advance the state-of-the-art in laser mirror cooling. Significant improvements can be achieved through the transfer of heat via working fluid phase change rather than specific heat capacity. These benefits include reduced jitter, and reduced electrical power consumption. In one actively pumped two phase cooling scheme, a saturated liquid is mechanically pumped into a porous metal layer under the mirror face where a fraction of the fluid is vaporized. The vapor-liquid mixture then leaves the face area and flows to a condenser. The condensate recirculates back to the mirror in a closed loop process. Because the working fluids have high latent heats of vaporization compared to their liquid heat capacities, a significant reduction in flow rate and pressure drop is possible. Analytical and experimental work has shown that a favorable combination of low distortion and low jitter is achievable with this approach. Also, since two phase heat transfer coefficients increase with increasing heat flux, a two phase cooled optic will achieve a lower distortion under non-uniform beam profiles. Jitter data were collected at absorbed heat fluxes up to 80 W/cm{sup 2} using a molybdenum demonstration mirror with methylamine coolant at 20{degrees}C. Low distortion coefficients were used as a design goal for this program at an absorbed heat flux up to 100 W/cm{sup 2}. A demonstration mirror was fabricated and tested for thermal/optical performance.Thermal performance levels in excess of 100 W/cm{sup 2} were demonstrated. Tests conducted at the TDTF showed thermal distortion coefficients at or below the design goal for absorbed heat fluxes up to levels in excess of 100 W/cm{sup 2}. No other cooling approach has been demonstrated that uses a low flow rate, low pressure drop cooling scheme, and demonstrates low jitter and low thermal distortion ...
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Activities of the PNC Nuclear Safety Working Group

Description: The Nuclear Safety Working Group of the Pacific Nuclear Council promotes nuclear safety cooperation among its members. Status of safety research, emergency planning, development of lists of technical experts, severe accident prevention and mitigation have been the topics of discussion in the NSWG. This paper reviews and compares the severe accident prevention and mitigation program activities in some of the areas of the Pacific Basin region based on papers presented at a special session organized by the NSWG at an ANS Topical Meeting as well as papers from other sources.
Date: December 31, 1991
Creator: Kato, W. Y.
Partner: UNT Libraries Government Documents Department

Adaptive techniques for reactor thermal-hydraulic calculations

Description: Reliable modeling of reactor thermal-hydraulic behavior requires the ability to correlate measured behaviors of parameters, such as temperature and pressure, with simulated results. The objective of this work is to develop and investigate a technique to match measured thermal-hydraulic data with subsets of the modeled results through the appropriate adjustment of parameters within the numerical solution. Specifically, the correlation of measured and observed parameters in a least squares is developed.
Date: December 31, 1991
Creator: Boman, C. E. & Doster, J. M.
Partner: UNT Libraries Government Documents Department

Addressing earthquake strong ground motion issues at the Idaho National Engineering Laboratory

Description: In the course of reassessing seismic hazards at the Idaho National Engineering Laboratory (INEL), several key issues have been raised concerning the effects of the earthquake source and site geology on potential strong ground motions that might be generated by a large earthquake. The design earthquake for the INEL is an approximate moment magnitude (M{sub w}) 7 event that may occur on the southern portion of the Lemhi fault, a Basin and Range normal fault that is located on the northwestern boundary of the eastern Snake River Plain and the INEL, within 10 to 27km of several major facilities. Because the locations of these facilities place them at close distances to a large earthquake and generally along strike of the causative fault, the effects of source rupture dynamics (e.g., directivity) could be critical in enhancing potential ground shaking at the INEL. An additional source issue that has been addressed is the value of stress drop to use in ground motions predictions. In terms of site geology, it has been questioned whether the interbedded volcanic stratigraphy beneath the ESRP and the INEL attenuates ground motions to a greater degree than a typical rock site in the western US. These three issues have been investigated employing a stochastic ground motion methodology which incorporates the Band-Limited-White-Noise source model for both a point source and finite fault, random vibration theory and an equivalent linear approach to model soil response.
Date: December 31, 1991
Creator: Wong, I. G.; Silva, W. J.; Stark, C. L.; Jackson, S. & Smith, R. P.
Partner: UNT Libraries Government Documents Department

Adiabatic disruption of asymmetric colliding beams

Description: A scheme is considered for enhancing the luminosity of electron-positron colliders. One of the beams is taken to be much denser than the other and effectively becomes a lens for the second beam. The luminosity enhancement afforded by this asymmetric disruption process is estimated analytically. The scheme is severely limited by the kink instability which is characterized by a two-stream dispersion relation, and a constraint on the density of the less dense beam is found for which the instability is gradient stabilized.
Date: December 31, 1991
Creator: Katsouleas, T. & Wurtele, J. S.
Partner: UNT Libraries Government Documents Department

[Adsorption and diffusion of fluids in well-characterized adsorbent materials]. Annual technical progress report, September 1, 1988--July 31, 1991

Description: This grant covers theoretical and molecular simulation studies in two areas: the thermodynamic behavior of associating liquids and their mixtures in the bulk phase, and the behavior of fluids in narrow pores. Fluids of longer chains are being simulated to test the perturbation theory. The Helmholtz free energy equation with the first order theory for association was applied to a wide variety of pure and mixed fluids; good agreement with experiment was found. In the second area, the nonlocal form of density functional theory was used together with molecular simulation (grand canonical Monte Carlo and molecular dynamics methods) to study pure and mixed fluids in pores. The fluids were organic compounds and argon; the porous materials were graphite, aluminophosphates, molecular sieves, and clays. 16 refs, 6 figs. (DLC)
Date: December 31, 1991
Partner: UNT Libraries Government Documents Department

Advanced atomization concept for CWF burning in small combustors. Phase 2, Quarterly technical progress report No. 3, 1 April 1991--30 June 1991

Description: The present project involves the second phase of research on a new concept in coal-water fuel (CWF) atomization that is applicable to burning in small combustors. It is intended to address the most important problem associated with CWF combustion; i.e., production of small spray droplets in an efficient manner by an atomization device. Phase 1 of this work was successfully completed with the development of an opposed-jet atomizer that met the goals of the first contract. Performance as a function of operating conditions was measured, and the technical feasibility of the device established in the Atlantic Research Atomization Test Facility employing a Malvern Particle Size Analyzer. Testing then proceeded to a combustion stage in a test furnace at a firing rate of 0.5 to 1.5 MMBtu/H.
Date: December 31, 1991
Creator: Heaton, H. & McHale, E.
Partner: UNT Libraries Government Documents Department

Advanced Combustion System for Industrial Boilers. Phase 2, Quarterly Technical Progress Report, April--June 1991

Description: During this quarter, several coal combustion tests were carded out in the boiler using the eductor coal feed system and the two-stage combustor. The coal feed system and combustor are shown in Figures 2.1 and 2.2. The main goal for these tests was to determine the optimum combustor setup for low NO{sub x} emissions while maintaining good carbon conversion efficiency. It was found during the tests that the amount of air introduced into the combustor along with the coal through the eductor tailpipe was a critical parameter for both NO{sub x} formation and carbon conversion. Using the new fluidized coal hopper discharge arrangement, the air required for eductor operation varies from about 12 percent of the total combustion air at a 2 MBtu/h firing rate to about 8 percent at 4 and 6 MBtu/h. (During previous testing using the old coal tank, the eductor air requirement was about 12 percent at 4 MBtu/h.) In initial tests, only the amount of air needed for eductor operation was introduced through the tailpipe. Combustor operation under this condition was satisfactory at 2 MBtu/h but not at 4 or 6 MBtu/h. At 4 and 6 MBtu/h firing rates, carbon conversion was typically less than 98 percent (based on ash exiting the stack), and CO was relatively high. It was necessary to operate the combustor at a primary stoichiometry of 0.40 or less in order to meet the goal of 0.6 lb/MBtu for NO{sub x} emission.
Date: December 31, 1991
Creator: Wagoner, C. L.; Foote, J. P.; Millard, W. P.; Attig, R. C. & Schulz, R. J.
Partner: UNT Libraries Government Documents Department