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A rapid, semiempirical method of calculating the stability margins of superconductors cooled with subcooled He-II: (Final report)

Description: A rapid, semiempirical method is presented for calculating the stability margins of superconductors cooled with subcooled He-II. Based on a model of Seyfert, the method takes into account both time-dependent Gorter-Mellink heat transport and the effects of interfacial Kapitza resistance. The method has been compared favorably with heat transfer data of Seyfert, stability data of Meuris, and stability data of Pfotenhauer and van Sciver. 4 refs., 7 figs., 1 tab.
Date: January 1, 1986
Creator: Dresner, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calculation of external dose from distributed source

Description: This paper discusses a relatively simple calculational method, called the point kernel method (Fo68), for estimating external dose from distributed sources that emit photon or electron radiations. The principles of the point kernel method are emphasized, rather than the presentation of extensive sets of calculations or tables of numerical results. A few calculations are presented for simple source geometries as illustrations of the method, and references and descriptions are provided for other … more
Date: January 1, 1986
Creator: Kocher, David C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Predictive models for thermal hazards. [lowest constant surface temperature at which material of given size and shape will self-heat to catastrophic destruction]

Description: Many self-heating accidents with energetic materials have occurred when operations that have been done safely on a small scale are attempted on a larger scale. They have also occurred when a material is heated for a longer time or to a higher temperature than is normal for its processing or storage, such as might be caused by equipment malfunction or power failure. To prevent self-heating accidents, we must be able to predict the critical temperature for the size and shape of the material we ar… more
Date: January 1, 1986
Creator: Janney, J.L. & Rogers, R.N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cascade diffusion theory of displacement-induced point defect concentration and flux fluctuations

Description: A theoretical approach, which has been developed to assess the fluctuations in point defect concentrations and fluxes to sinks that are induced by the production of point defects in spatially and temporally discrete cascades, is summarized. Solutions for cascade dissipation are outlined for the case where cascades occur in a homogeneous lossy medium as well as for the more involved geometries where cascades occur in the presence of a nearby dislocation or cavity. By superposition of solutions r… more
Date: 1986~
Creator: Mansur, L.K.; Brailsford, A.D. & Coghlan, W.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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FPIN2 code: an application of the finite element method to the analysis of the transient response of oxide and metal fuel elements

Description: The FPIN2 code simulates the thermal-mechanical response of fast reactor fuel pins to transient events. Temperatures of the fuel pin and coolant are calculated using a simple pin-in-a-pipe geometry. The mechanical analysis uses an implicit finite element formulation with linear shape functions which allow for general material behavior in the fuel and cladding including cracking and melting. This formulation provides a very convenient structure for implementing different models and improvements … more
Date: January 1, 1986
Creator: Hughes, T. H. & Kramer, J. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Limit cycles and bifurcations in nuclear systems

Description: This work provides a basis for scoping calculations to determine the dynamic behavior - both linear and nonlinear - of BWRs. Additional work is now underway to establish the feasibility of routine operation of nuclear systems in the nonlinear (limit-cycle) regime.
Date: January 1, 1986
Creator: Cacuci, D. G.; March-Leuba, J. & Perez, R. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Integrated heat pipe-thermal storage design for a solar receiver. [Constant power source with heat from sun or from storage]

Description: Light-weight heat pipe wall elements that incorporate a thermal storage subassembly within the vapor space are being developed as part of the Organic Rankine Cycle Solar Dynamic Power Systems (ORC-SDPS) receiver for the space station application. The operating temperature of he heat pipe elements is in the 770 to 810/sup 0/K range with a design power throughput of 4.8 kW per pipe. The total heat pipe length is 1.9 M. The Rankine cycle boiler heat transfer surfaces are positioned within the heat… more
Date: January 1, 1986
Creator: Keddy, E.S.; Sena, J.T.; Woloshun, K.; Merrigan, M.A. & Heidenreich, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Circular machine design techniques and tools

Description: Some of the basic optics principles involved in the design of circular accelerators such as Alternating Gradient Synchrotrons, Storage and Collision Rings, and Pulse Stretcher Rings are outlined. Typical problems facing a designer are defined, and the main references and computational tools are reviewed that are presently available. Two particular classes of problems that occur typically in accelerator design are listed - global value problems, which affect the control of parameters which are c… more
Date: April 1, 1986
Creator: Servranckx, R.V. & Brown, K.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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RSMASS: A Preliminary Reactor/Shield Mass Model for SDI Applications

Description: A simple mathematical model (RSMASS) has been developed to provide rapid estimates of reactor and shield masses for space-based reactor power systems. Approximations are used rather than correlations or detailed calculations to estimate the reactor fuel mass and the masses of the moderator, structure, reflector, pressure vessel, miscellaneous components, and the reactor shield. The fuel mass is determined either by neutronics limits, specific power limits, or fuel burnup limits - whichever yiel… more
Date: August 1, 1986
Creator: Marshall, Albert C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DANDE: a linked code system for core neutronics/depletion analysis

Description: This report describes DANDE - a modular neutronics, depletion code system for reactor analysis. It consists of nuclear data processing, core physics, and fuel depletion modules, and allows one to use diffusion and transport methods interchangeably in core neutronics calculations. This latter capability is especially important in the design of small modular cores. Additional unique features include the capability of updating the nuclear data file during a calculation; a detailed treatment of dep… more
Date: January 1, 1986
Creator: LaBauve, R. J.; England, T. R.; George, D. C.; MacFarlane, R. E. & Wilson, W. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy storage transformer power conditioning systems for Megajoule class flux compression generators

Description: Circuit and energy storage transformer configurations are developed to match high impedance loads to low impedance sources. With the secondary open, a large di/dt is produced in the primary circuit by inserting a resistance, characteristic of an opening switch, and the load circuit is connected using a preset spark gap. Transformer design concepts using a foil-MYLAR ''sandwich'' for the secondary winding are described, permitting close primary-secondary coupling. Transformer experiments driven … more
Date: January 1, 1986
Creator: Reinovsky, R. E.; Colclaser, R. G.; Welby, J. M. & Lopez, E. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calculational technique to predict combustible gas generation in sealed radioactive waste containers

Description: Certain forms of nuclear waste, when subjected to ionizing radiation, produce combustible mixtures of gases. The production of these gases in sealed radioactive waste containers represents a significant safety concern for the handling, shipment and storage of waste. The US Nuclear Regulatory Commission (NRC) acted on this safety concern in September 1984 by publishing an information notice requiring waste generators to demonstrate, by tests or measurements, that combustible mixtures of gases ar… more
Date: May 1, 1986
Creator: Flaherty, J. E.; Fujita, A.; Deltete, C. P. & Quinn, G. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Plant analyzer development for high-speed interactive simulation of BWR plant transients

Description: Advanced modeling techniques have been combined with modern, special-purpose peripheral minicomputer technology to develop a plant analyzer which provides realistic and accurate predictions of plant transients and severe off-normal events in nuclear power plants through on-line simulations at speeds of approximately 10 times faster than actual process speeds. The new simulation technology serves not only for carrying out routinely and efficiently safety analyses, optimizations of emergency proc… more
Date: January 1, 1986
Creator: Wulff, W.; Cheng, H.S. & Mallen, A.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Reflected kinetics model for nuclear space reactor kinetics and control scoping calculations

Description: The objective of this research is to develop a model that offers an alternative to the point kinetics (PK) modelling approach in the analysis of space reactor kinetics and control studies. Modelling effort will focus on the explicit treatment of control drums as reactivity input devices so that the transition to automatic control can be smoothly done. The proposed model is developed for the specific integration of automatic control and the solution of the servo mechanism problem. The integratio… more
Date: May 1, 1986
Creator: Washington, K.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calculations for isotopically-tailored ceramics in fission and fusion reactors

Description: Information and understanding of the response of a ceramic at dpa and gas production rates near those expected at the first wall of a fusion reactor can be obtained by an experiment in a fission reactor to irradiate an isotopically tailored sample of the ceramic. To aid in the design of such an experiment, we have made calculations to determine the amount of /sup 15/N and /sup 17/O needed in Si/sub 3/Al/sub 3/O/sub 3/N/sub 5/ and /sup 17/O needed in Al/sub 2/O/sub 3/ to simulate the behavior of… more
Date: January 1, 1986
Creator: LaBauve, R.J.; Livak, R.J. & Clinard, F.W. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparison of TRAC-PF1/MOD1 to a no-failure UPI test in the Cylindrical Core Test Facility

Description: TRAC-PF1/MOD1 is compared to a no-failure upper plenum injection reflood test in the Cylindrical Core Test Facility. The results show that TRAC can accurately predict the asymmetric channeling of fluid from upper plenum into the core and that a multidimensional modeling capability is required to do so. The rod temperature behavior is accurately predicted for both the peak cladding temperature and the quench time in the high- and low-power zones. Excessive downflow of liquid at the tie plate is … more
Date: January 1, 1986
Creator: Cappiello, M. & Spore, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Designing CNR, a very high thermal neutron flux facility

Description: According to a recent study (Eastman-Seitz Committee, National Academy of Science) there is a need for a new generation of steady neutron sources with a thermal neutron flux peak between 5 to 10 times 10/sup 15//cm/sup 2/ sec. Ideally the neutron source would have to operate continuously for several days (two weeks at least) with minimum time (2 to 3 days) for refueling and/or maintenance and it would also be used to irradiate materials and produce isotopes. This paper describes the preliminary… more
Date: January 1, 1986
Creator: Difilippo, F. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermal shield support degradation in pressurized water reactors

Description: Damage to the thermal shield support structures of three pressurized water reactors (PWRs) due to flow-induced vibrations was recently discovered during refueling. In two of the reactors, severe damage occurred to the thermal shield, and in one reactor the core support barrel (CSB) was damaged, necessitating extended outages for repairs. In all three reactors, several of the thermal shield supports were either loose, damaged, or missing. The three plants had been in operation for approximately … more
Date: January 1, 1986
Creator: Sweeney, F. J. & Fry, D. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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TRAC code development status and plans

Description: This report summarizes the characteristics and current status of the TRAC-PF1/MOD1 computer code. Recent error corrections and user-convenience features are described, and several user enhancements are identified. Current plans for the release of the TRAC-PF1/MOD2 computer code and some preliminary MOD2 results are presented. This new version of the TRAC code implements stability-enhancing two-step numerics into the 3-D vessel, using partial vectorization to obtain a code that has run 400% fast… more
Date: January 1, 1986
Creator: Spore, J. W.; Liles, D. R.; Nelson, R. A.; Dotson, P. J.; Steinke, R. G.; Knight, T. D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Accelerator dynamics and beam aperture

Description: We present an analytical method for analyzing accelerator dynamics, including higher order effects of multipoles on the beam. This formalism provides a faster alternative to particle tracking. Simplectic expressions for the emittance and phase describing the dynamical behavior of a particle in a circular accelerator are derived using second order perturbation theory (in the presence of nonlinear elements, e.g., sextupoles, octupoles). These expressions are successfully used to calculate the emi… more
Date: October 1, 1986
Creator: Parsa, Z.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Blast wave effects at short distances

Description: The peak shock overpressures for a blast wave have been calculated by several methods, and the results have been verified by a large number of experimental measurements. The use of the standard overpressure curve, however, may lead to serious underestimation of blast wave effects at very short distances (probably at scaled distances of less than one meter). We have calculated the blast wave from a detonating sphere of explosive using the one-dimensional reactive hydrodynamics code HYDROX, and h… more
Date: January 1, 1986
Creator: Bowman, A.L. & Idar, E.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical evaluation of matrix effects on trapped atomic levels

Description: We suggest a theoretical model for calculating the matrix perturbation on the spectra of atoms trapped in rare gas systems. The model requires the ''potential curves'' of the diatomic system consisting of the trapped atom interacting with one from the matrix and relies on the approximation that the total matrix perturbation is a scalar sum of the pairwise interactions with each of the lattice sites. Calculations are presented for the prototype systems Na in Ar. Attempts are made to obtain ab in… more
Date: June 1, 1986
Creator: Das, G.P. & Gruen, D.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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New buildup factor data for point kernel calculations

Description: An American Nuclear Society Standards Committee Working Group, identified as ANS-6.4.3, is developing a set of evaluated gamma-ray isotropic point-source buildup factors and attenuation coefficients for a standard reference data base. As a first step, a largely unpublished set of buildup factors calculated with the moments method has been evaluated by recalculating key values with Monte Carlo, integral transport, and discrete ordinates methods. Attention is being given to frequently-neglected p… more
Date: January 1, 1986
Creator: Trubey, D. K. & Harima, Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Time constants and feedback transfer functions of EBR-II (Experimental Breeder Reactor) subassembly types

Description: Time constants, feedback reactivity transfer functions and power coefficients are calculated for stereotypical subassemblies in the EBR-II reactor. These quantities are calculated from nodal reactivities obtained from a reactor kinetic code analysis for a step change in power. Due to the multiplicity of eigenvalues, there are several time constants for each nodal position in a subassembly. Compared with these calculated values are analytically derived values for the initial node of a given chan… more
Date: September 1, 1986
Creator: Grimm, K. N. & Meneghetti, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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