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Potential for efficient frequency conversion at high average power using solid state nonlinear optical materials (open access)

Potential for efficient frequency conversion at high average power using solid state nonlinear optical materials

High-average-power frequency conversion using solid state nonlinear materials is discussed. Recent laboratory experience and new developments in design concepts show that current technology, a few tens of watts, may be extended by several orders of magnitude. For example, using KD*P, efficient doubling (>70%) of Nd:YAG at average powers approaching 100 KW is possible; and for doubling to the blue or ultraviolet regions, the average power may approach 1 MW. Configurations using segmented apertures permit essentially unlimited scaling of average power. High average power is achieved by configuring the nonlinear material as a set of thin plates with a large ratio of surface area to volume and by cooling the exposed surfaces with a flowing gas. The design and material fabrication of such a harmonic generator are well within current technology.
Date: October 28, 1985
Creator: Eimerl, D.
Object Type: Report
System: The UNT Digital Library
Light-Weight Radioisotope Heater Unit Safety Analysis Report (LWRHU-SAR). Volume I. A. Introduction and executive summary. B. Reference Design Document (RDD) (open access)

Light-Weight Radioisotope Heater Unit Safety Analysis Report (LWRHU-SAR). Volume I. A. Introduction and executive summary. B. Reference Design Document (RDD)

The orbiter and probe portions of the NASA Galileo spacecraft contain components which require auxiliary heat during the mission. To meet these needs, the Department of Energy's (DOE's) Office of Special Nuclear Projects (OSNP) has sponsored the design, fabrication, and testing of a one-watt encapsulated plutonium dioxide-fueled thermal heater named the Light-Weight Radioisotope Heater Unit (LWRHU). This report addresses the radiological risks which might be encountered by people both at the launch area and worldwide should postulate mission failures or malfunctions occur, which would result in the release of the LWRHUs to the environment. Included are data from the design, mission descriptions, postulated accidents with their consequences, test data, and the derived source terms and personnel exposures for the various events.
Date: October 1, 1985
Creator: Johnson, E. W.
Object Type: Report
System: The UNT Digital Library
Three novel tokamak plasma regimes in TFTR (open access)

Three novel tokamak plasma regimes in TFTR

Aside from extending ''standard'' ohmic and neutral beam heating studies to advanced plasma parameters, TFTR has encountered a number of special plasma regimes that have the potential to shed new light on the physics of tokamak confinement and the optimal design of future D-T facilities: (1) High-powered, neutral beam heating at low plasma densities can maintain a highly reactive hot-ion population (with quasi-steady-state beam fueling and current drive) in a tokamak configuration of modest bulk-plasma confinement requirements. (2) Plasma displacement away from limiter contact lends itself to clarification of the role of edge-plasma recycling and radiation cooling within the overall pattern of tokamak heat flow. (3) Noncentral auxiliary heating (with a ''hollow'' power-deposition profile) should serve to raise the central tokamak plasma temperature without deterioration of central region confinement, thus facilitating the study of alpha-heating effects in TFTR. The experimental results of regime (3) support the theory that tokamak profile consistency is related to resistive kink stability and that the global energy confinement time is determined by transport properties of the plasma edge region.
Date: October 1, 1985
Creator: Furth, H.P.
Object Type: Report
System: The UNT Digital Library
Extended characterization of M-Area settling basin and vicinity. Technical data summary. Revision (open access)

Extended characterization of M-Area settling basin and vicinity. Technical data summary. Revision

The Savannah River Plant M-Area settling basin, an unlined surface impoundment, has received process effluents from the M-Area fuel and target fabrication facilities since 1958. The waste effluents have contained metal degreasing agents (chlorinated hydrocarbons), acids, caustics, and heavy metals. Data analyses are provided.
Date: October 1, 1985
Creator: Pickett, J B
Object Type: Report
System: The UNT Digital Library
Dynamic modeling of transport and positional control of tokamaks (open access)

Dynamic modeling of transport and positional control of tokamaks

We describe here a numerical model of a free boundary axisymmetric tokamak plasma and its associated control systems. The plasma is modeled with a hybrid method using two-dimensional velocity and flux functions with surface-averaged MHD equations describing the evolution of the adiabatic invariants. Equations are solved for the external circuits and for the effects of eddy currents in nearby conductors. The method is verified by application to several test problems and used to simulate the formation of a bean-shaped plasma in the PBX experiment.
Date: October 1, 1985
Creator: Jardin, S. C.; Pomphrey, N. & DeLucia, J.
Object Type: Report
System: The UNT Digital Library
TRU Waste Management Program cost/schedule optimization analysis (open access)

TRU Waste Management Program cost/schedule optimization analysis

The cost/schedule optimization task is a necessary function to insure that program goals and plans are optimized from a cost and schedule aspect. Results of this study will offer DOE information with which it can establish, within institutional constraints, the most efficient program for the long-term management and disposal of contact handled transuranic waste (CH-TRU). To this end, a comprehensive review of program cost/schedule tradeoffs has been made, to identify any major cost saving opportunities that may be realized by modification of current program plans. It was decided that all promising scenarios would be explored, and institutional limitations to implementation would be described. Since a virtually limitless number of possible scenarios can be envisioned, it was necessary to distill these possibilities into a manageable number of alternatives. The resultant scenarios were described in the cost/schedule strategy and work plan document. Each scenario was compared with the base case: waste processing at the originating site; transport of CH-TRU wastes in TRUPACT; shipment of drums in 6-Packs; 25 year stored waste workoff; WIPP operational 10/88, with all sites shipping to WIPP beginning 10/88; and no processing at WIPP. Major savings were identified in two alternate scenarios: centralize waste processing at INEL and …
Date: October 1, 1985
Creator: Detamore, J. A. (Rockwell International Corp., Albuquerque, NM (United States). Joint Integration Office); Raudenbush, M. H.; Wolaver, R. W. & Hastings, G. A. (Stoller (S.M.) Corp., Boulder, CO (United States))
Object Type: Report
System: The UNT Digital Library
Confinement scaling and ignition in tokamaks (open access)

Confinement scaling and ignition in tokamaks

A drift wave turbulence model is used to compute the scaling and magnitude of central electron temperature and confinement time of tokamak plasmas. The results are in accord with experiment. Application to ignition experiments shows that high density (1 to 2) . 10/sup 15/ cm/sup -3/, high field, B/sub T/ > 10 T, but low temperature T approx. 6 keV constitute the optimum path to ignition.
Date: October 1, 1985
Creator: Perkins, F.W. & Sun, Y.C.
Object Type: Report
System: The UNT Digital Library
Business developments of nonthermal solar technologies (open access)

Business developments of nonthermal solar technologies

Information on the developments of nonthermal solar technologies is presented. The focus is on the success of wind energy conversion systems (WECS) and photovoltaics. Detailed information on the installed generating capacity, market sectors, financing sources, systems costs and warranties of WECS and photovoltaic systems is summarized. (BCS)
Date: October 1, 1985
Creator: Smith, S.A.; Watts, R.L. & Williams, T.A.
Object Type: Report
System: The UNT Digital Library
Characterization of the solid, airborne materials created when UF/sub 6/ reacts with moist air flowing in single-pass mode (open access)

Characterization of the solid, airborne materials created when UF/sub 6/ reacts with moist air flowing in single-pass mode

A series of experiments has been performed in which UF/sub 6/ was released into flowing air in order to characterize the solid particulate material produced under non-static conditions. In two of the experiments, the aerosol was allowed to stagnate in a static chamber after release and examined further but in the other experiments characterization was done only on material collected a few seconds after release. Transmission electron microscopy and mass measurement by cascaded impactor were used to characterize the aerosol particles which were usually single spheroids with little agglomeration in evidence. The goal of the work is to determine the chemistry and physics of the UF/sub 6/-atmospheric moisture reaction under a variety of conditions so that information about resulting species and product morphologies is available for containment and removal (knockdown) studies as well as for dispersion plume modeling and toxicology studies. This report completes the milestone for reporting the information obtained from releases of UF/sub 6/ into flowing rather than static air. 26 figs., 3 tabs.
Date: October 1, 1985
Creator: Pickrell, P. W.
Object Type: Report
System: The UNT Digital Library
TOPAZ - the transient one-dimensional pipe flow analyzer: code validation and sample problems (open access)

TOPAZ - the transient one-dimensional pipe flow analyzer: code validation and sample problems

TOPAZ is a ''user friendly'' computer code for modeling the one-dimensional-transient physics of multi-species gas transfer in arbitrary arrangements of pipes, valves, vessels, and flow branches. This document presents a series of sample problems designed to aid potential users in creating TOPAZ input files. To the extent possible, sample problems were selected for which analytical solutions currently exist. TOPAZ comparisons with such solutions are intended to provide a measure of code validation.
Date: October 1, 1985
Creator: Winters, W.S.
Object Type: Report
System: The UNT Digital Library
(Performance evaluation of fabric bag filters on a bench-scale coal gasifier) (open access)

(Performance evaluation of fabric bag filters on a bench-scale coal gasifier)

The objective of the proposed work is to demonstrate the operational and economic feasibility of using high-temperature ceramic filters for particulate control in a variety of coal gasification power generating systems.
Date: October 11, 1985
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Resistive instabilities in tokamaks (open access)

Resistive instabilities in tokamaks

Low-m tearing modes constitute the dominant instability problem in present-day tokamaks. In this lecture, the stability criteria for representative current profiles with q(0)-values slightly less than unit are reviewed; ''sawtooth'' reconnection to q(0)-values just at, or slightly exceeding, unity is generally destabilizing to the m = 2, n = 1 and m = 3, n = 2 modes, and severely limits the range of stable profile shapes. Feedback stabilization of m greater than or equal to 2 modes by rf heating or current drive, applied locally at the magnetic islands, appears feasible; feedback by island current drive is much more efficient, in terms of the radio-frequency power required, then feedback by island heating. Feedback stabilization of the m = 1 mode - although yielding particularly beneficial effects for resistive-tearing and high-beta stability by allowing q(0)-values substantially below unity - is more problematical, unless the m = 1 ideal-MHD mode can be made positively stable by strong triangular shaping of the central flux surfaces. Feedback techniques require a detectable, rotating MHD-like signal; the slowing of mode rotation - or the excitation of non-rotating modes - by an imperfectly conducting wall is also discussed.
Date: October 1, 1985
Creator: Rutherford, P.H.
Object Type: Report
System: The UNT Digital Library
Comparison of predicted and measured fission product behavior in the Fort St. Vrain HTGR during the first three cycles of operation (open access)

Comparison of predicted and measured fission product behavior in the Fort St. Vrain HTGR during the first three cycles of operation

Fission product release from the reactor core has been predicted by the reference design methods and compared with reactor surveillance measurements and with the results of postirradiation examination (PIE) of spent FSV fuel elements. Overall, the predictive methods have been shown to be conservative: the predicted fission gas release at the end of Cycle 3 is about five times higher than observed. The dominant source of fission gas release is as-manufactured, heavy-metal contamination; in-service failure of the coated fuel particles appears to be negligible which is consistent with the PIE of spent fuel elements removed during the first two refuelings. The predicted releases of fission metals are insignificant compared to the release and subsequent decay of their gaseous precursors which is consistent with plateout probe measurements.
Date: October 1, 1985
Creator: Hanson, D. L.; Jovanovic, V. & Burnette, R. D.
Object Type: Article
System: The UNT Digital Library
Site selection experience for a new low-level radioactive waste storage/disposal facility at the Savannah River Plant (open access)

Site selection experience for a new low-level radioactive waste storage/disposal facility at the Savannah River Plant

Preliminary performance criteria and site selection guides specific to the Savannah River Plant, were developed for a new low-level radioactive waste storage/disposal facility. These site selection guides were applied to seventeen potential sites identified at SRP. The potential site were ranked based on how well they met a set of characteristics considered important in site selection for a low-level radioactive waste disposal facility. The characteristics were given a weighting factor representing its relative importance in meeting site performance criteria. A candidate site was selected and will be the subject of a site characterization program.
Date: October 1, 1985
Creator: Towler, O. A.; Cook, J. R. & Helton, B. D.
Object Type: Article
System: The UNT Digital Library
Stochastic particle acceleration and statistical closures (open access)

Stochastic particle acceleration and statistical closures

In a recent paper, Maasjost and Elsasser (ME) concluded, from the results of numerical experiments and heuristic arguments, that the Bourret and the direct-interaction approximation (DIA) are ''of no use in connection with the stochastic acceleration problem'' because (1) their predictions were equivalent to that of the simpler Fokker-Planck (FP) theory, and (2) either all or none of the closures were in good agreement with the data. Here some analytically tractable cases are studied and used to test the accuracy of these closures. The cause of the discrepancy (2) is found to be the highly non-Gaussian nature of the force used by ME, a point not stressed by them. For the case where the force is a position-independent Ornstein-Uhlenbeck (i.e., Gaussian) process, an effective Kubo number K can be defined. For K << 1 an FP description is adequate, and conclusion (1) of ME follows; however, for K greater than or equal to 1 the DIA behaves much better qualitatively than the other two closures. For the non-Gaussian stochastic force used by ME, all common approximations fail, in agreement with (2).
Date: October 1, 1985
Creator: Dimits, A. M. & Krommes, J. A.
Object Type: Report
System: The UNT Digital Library
Marketing energy conservation options to Northwest manufactured home buyers. Revision 1 (open access)

Marketing energy conservation options to Northwest manufactured home buyers. Revision 1

Manufactured, or HUD-Code, homes comprise a growing share of the housing stock in the Northwest, as well as nationally. Their relatively low cost has made them especially attractive to lower income families, first-time home-buyers, and retired persons. The characteristics of manufactured home (MH) buyers, the unique energy consumption characteristics of the homes, and their increasing market share make this market an especially critical one for energy consumption and conservation planning in the Northwest. This study relies on extensive, existing survey data and new analyses to develop information that can potentially assist the design of a marketing plan to achieve energy conservation in new manufactured homes. This study has the objective of assisting BPA in the development of a regional approach in which numerous organizations and parties would participate to achieve conservation in new manufactured homes. A previous survey and information collected for this study from regional dealers and manufacturers provide an indication of the energy conservation options being sold to manufactured home buyers in the PNW. Manufacturers in the Northwest appear to sell homes that usually exceed the HUD thermal requirements. Manufacturers typically offer efficiency improvements in packages that include fixed improvements in insulation levels, glazing, and infiltration control. Wholesale …
Date: October 1, 1985
Creator: Hendrickson, P. L.; Mohler, B. L.; Taylor, Z. T.; Lee, A. D. & Onisko, S. A.
Object Type: Report
System: The UNT Digital Library
Opportunities in pulse combustion (open access)

Opportunities in pulse combustion

In most pulse combustors, the combustion occurs near the closed end of a tube where inlet valves operate in phase with the pressure amplitude variations. Thus, within the combustion zone, both the temperature and the pressure oscillate around a mean value. However, the development of practical applications of pulse combustion has been hampered because effective design requires the right combination of the combustor's dimensions, valve characteristics, fuel/oxidizer combination, and flow pattern. Pulse combustion has several additional advantages for energy conversion efficiency, including high combustion and thermal efficiency, high combustion intensity, and high convective heat transfer rates. Also, pulse combustion can be self-aspirating, generating a pressure boost without using a blower. This allows the use of a compact heat exchanger that may include a condensing section and may obviate the need for a chimney. In the last decade, these features have revived interest in pulse combustion research and development, which has resulted in the development of a pulse combustion air heater by Lennox, and a pulse combustion hydronic unit by Hydrotherm, Inc. To appraise this potential for energy savings, a systematic study was conducted of the many past and present attempts to use pulse combustion for practical purposes. The authors recommended …
Date: October 1, 1985
Creator: Brenchley, D.L. & Bomelburg, H.J.
Object Type: Report
System: The UNT Digital Library
Feasibility study for aquaculture and space heating, Ft. Bidwell, California (open access)

Feasibility study for aquaculture and space heating, Ft. Bidwell, California

Expansion of the aquaculture facilities and geothermal space heating at Ft. Bidwell, California were investigated. The lack of cold water is the limiting factor for aquaculture expansion and is also a problem for the town domestic water supply. A new cold water well approximately 1200 feet deep would provide for the aquaculture expansion and additional domestic water. A 2900 foot test well can be completed to provide additional hot water at approximately 200/sup 0/F and an estimated artesian flow of 500 gpm. If these wells are completed, the aquaculture facility could be expanded to produce 6000 two pound catfish per month on a continuous basis and provide space heating of at least 20 homes. The design provided allows for heating 11 homes initially with possible future expansion. 9 figs.
Date: October 1, 1985
Creator: Culver, G.
Object Type: Report
System: The UNT Digital Library
Outplanting Anadromous Salmonids, A Lilterature Study. (open access)

Outplanting Anadromous Salmonids, A Lilterature Study.

This paper presents a list of more than 200 references on topics associated with offstation releases of hatchery stocks of anadromous fish used to supplement or reestablish wild rearing. The narrative briefly reviews influences of genetics, rearing density of fish in the natural environment, survival rates observed from outplanted stocks, and estimation procedures for stocking rates and rearing densities. We have attempted to summarize guidelines and recommendations for fishery managers to consider. Based on tagging studies, a typical smolt release from a Willamette River hatchery would return 0.29% of the smolts to the stream of release as adults. Catch to escapement ratios for adult Willamette chinook vary widely between broods, but on average two fish are caught for each fish that escapes. The catch is about evenly divided between offshore and freshwater harvest. British Columbia is the primary location of offshore harvest, and the lower Willamette River is the primary location of freshwater harvest. Review of departmental policy indicates that only Willamette stock spring chinook are currently acceptable for use in a proposed outplant study within the Willamette basin. Further, most Oregon Department of Fish and Wildlife district management biologists would prefer not to transfer any stocks of spring chinook …
Date: October 1, 1985
Creator: Smith, Eugene M.
Object Type: Report
System: The UNT Digital Library
Propagation of ion beams through a tenuous magnetized plasma (open access)

Propagation of ion beams through a tenuous magnetized plasma

When an ion beam is propagated through a plasma, the question of charge neutralization is critical to its propagation. We consider such a problem where the plasma is magnetized with magnetic field perpendicular to the beam. The plasma-number density and beam-number density are assumed comparable. We reduce the problem to a two-dimensional model, which we solve. The solution suggests that it should be possible to attain charge neutralization if the beam density is properly varied along itself.
Date: October 1, 1985
Creator: Chrien, E. F.; Valeo, E. J.; Kulsrud, R. M. & Oberman, C. R.
Object Type: Report
System: The UNT Digital Library
Generalized banana-drift transport (open access)

Generalized banana-drift transport

The theory of tokamak ripple transport in the banana-drift and ripple-plateau regimes is extended in a number of directions. The theory is valid for small values of the toroidal periodicity number n of the perturbation, as well as for the moderate values (n approx. 10 to 20) previously assumed. It is shown that low-n perturbations can produce much greater transport than the larger-n perturbations usually studied. In addition, the ripple perturbation is allowed arbitrary values of poloidal mode number m and frequency ..omega.., making it applicable to the transport induced by MHD modes. Bounce averaging is avoided, so the theory includes the contributions to transport from all harmonics of the bounce frequency, providing a continuous description of the transition from the banana drift to the ripple-plateau regime. The implications of the theory for toroidal rotation in tokamaks are considered.
Date: October 1, 1985
Creator: Mynick, H.E.
Object Type: Report
System: The UNT Digital Library
1-2 GeV synchrotron radiation facility at Lawrence Berkeley Laboratory (open access)

1-2 GeV synchrotron radiation facility at Lawrence Berkeley Laboratory

The Advanced Light Source (ALS), a dedicated synchrotron radiation facility optimized to generate soft x-ray and vacuum ultraviole (XUV) light using magnetic insertion devices, was proposed by the Lawrence Berkeley Laboratory in 1982. It consists of a 1.3-GeV injection system, an electron storage ring optimized at 1.3 GeV (with the capability of 1.9-GeV operation), and a number of photon beamlines emanating from twelve 6-meter-long straight sections, as shown in Fig. 1. In addition, 24 bending-magnet ports will be avialable for development. The ALS was conceived as a research tool whose range and power would stimulate fundamentally new research in fields from biology to materials science (1-4). The conceptual design and associated cost estimate for the ALS have been completed and reviewed by the US Department of Energy (DOE), but preliminary design activities have not yet begun. The focus in this paper is on the history of the ALS as an example of how a technical construction project was conceived, designed, proposed, and validated within the framwork of a national laboratory funded largely by the DOE.
Date: October 1, 1985
Creator: Berkner, K.H.
Object Type: Article
System: The UNT Digital Library
Comparison of the CRAY X-MP-4, Fujitsu VP-200, and Hitachi S-810/20 : an Argonne Perspective (open access)

Comparison of the CRAY X-MP-4, Fujitsu VP-200, and Hitachi S-810/20 : an Argonne Perspective

A set of programs, gathered from major Argonne computer users, was run on the current generation of supercomputers: the CRAY X-MP-4, Fujitsu VP-200, and Hitachi S-810/20. The results show that a single processor of a CRAY X-MP-4 is a consistently strong performer over a wide range of problems. The Fujitsu and Hitachi excel on highly vectorized programs and offer an attractive opportunity to sites with IBM-compatible computers.
Date: October 1985
Creator: Dongarra, J. J. & Hinds, Alan
Object Type: Report
System: The UNT Digital Library
Quasi-Automatic Parallelization : a Simplified Approach to Multiprocessing (open access)

Quasi-Automatic Parallelization : a Simplified Approach to Multiprocessing

As multiprocessors become commercially available, a great deal of concern is being focused on the problems involved in writing and debugging software for such machines. Earlier work described the use of monitors implemented by macro processors to attain portable code. This work formulates a general-purpose monitor which simplifies the programming of a wide class of numeric algorithms. We believe that the approach of describing a set of schedulable units of computation advocated by Brown offers a real simplification for the applications programmer. In this paper, we propose a straight-forward programming paradigm for describing schedulable units of computation that allows the description of many algorithms with very little effort.
Date: October 1985
Creator: Glickfeld, B. W. & Overbeek, Ross A.
Object Type: Report
System: The UNT Digital Library