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Porous body model for predicting temperature distributions in wire wrapped fuel and blanket assemblies of a LMFBR

Description: Existing methods of thermal analysis of a wire wrapped rod bundle of a Liquid Metal Fast Breeder Reactor are based on the principle of subchannel analysis. A model for thermal transport in wire wrapped rod bundles is developed here. The model is similar in principle to the one which has long been successfully used in chemical engineering for heat and mass transfer in fixed beds of packed solids. By dividing the bundle into two predominant regions and applying the model of a porous body to a LMFBR assembly a simple procedure for calculating temperature distributions in LMFBR fuel and blanket assemblies has evolved. The results obtained were found to predict available data with as good a precision as do the more complex analyses. Correlations for the two empirical constants were obtained as functions of geometric parameters based on an extensive analysis of existing data. The LMFBR fuel assemblies operate in forced convection (negligible natural convection) under steady state conditions whereas the blanket assemblies may operate in forced or mixed convection (combined forced and free convection). Two different formulations of equations, corresponding to these two convection regimes, were developed using the same basic model. The calculation procedure for assemblies in forced convection (called ENERGY I) is considerably simpler than that (ENERGY II, ENERGY III) in mixed convection, where buoyancy effects become important. Therefore it is desirable to use ENERGY I for forced convection (although ENERGY II, III can also be used in forced convection, the computational times are fifteen fold greater). In order to determine when buoyancy effects become important a new criterion is developed. Given the power, the power skew, the operating and geometric characteristics of the bundle, the critical modified Grashof Number predicts when buoyancy effects become important. (auth)
Date: June 1, 1975
Creator: Khan, E.U.; Rohsenow, W.M.; Sonin, A.A. & Todreas, N.E.
Partner: UNT Libraries Government Documents Department

Manual for ENERGY I, II, III computer programs

Description: The ENERGY codes for predicting coolant temperature distributions in LMFBR were wrapped fuel and blanket assemblies are described. The mathematical models, data input, code listings, and sample problems are presented. (JWR)
Date: May 1, 1975
Creator: Khan, E.U.; Rohesnow, W.M.; Sonin, A.A. & Todreas, N.E.
Partner: UNT Libraries Government Documents Department

Luminescence process, refractory stabilities, and new and novel electronic states: scanning chemical reactions and novel products for laser induced isotope separation. Progress report, March 1, 1975--November 20, 1975

Description: The formulation and development of versatile oven systems for high temperature metal vaporation at temperatures greater than 2000$sup 0$C are discussed. The construction of an apparatus appropriate to the production and study of small metal aggregates M/sub n/ (2 less than or equal to n less than or equal to 6) is discussed at length. This includes a consideration of the construction and operation of an argon ion pumped dye laser system. The dye laser system will be used to induce fluorescence from the small metal aggregates, and thereby will lead to the study of their molecular electronic structure. The production of carbon vapor and the reaction of this vapor with metal atoms and metal dimers to form metal carbides is outlined. A thorough study of the luminescence process leading to a new understanding of those chemiluminescent phenomena occurring as a result of the ''single collision'' bimolecular reaction of metal atoms and metal dimers with select oxidants is outlined. Methods for the determination of upper bounds to the heats of sublimation and vaporization of those metals which can be strongly oxidized in a ''single collision'' bimolecular reaction are presented. Extremely simple methods by which one can infer the radiative lifetimes of metastable product chemiluminescing molecules are also discussed. Beginning efforts toward the formulation of new and novel catalytic surfaces via aggregate deposition are outlined. Current studies of the titanium oxide system are presented. These chemiluminescence studies allow the determination of a lower bound to the TiO dissociation energy and a determination of the heat of vaporization of titanium metal. (auth)
Date: November 1, 1975
Creator: Gole, J.L.
Partner: UNT Libraries Government Documents Department

Thermal neutron scattering studies of molecular dynamics and critical phenomena in fluids and solids. Annual progress report, December 1972--November 1973

Description: Results of research on quasielastic scattering in dense gases are reported. Results of dynamic structure factor measurements in liquid Ga are also reported. Work directed toward development for high resolution light scattering spectroscopy is summarized. (JRD)
Date: January 1, 1973
Creator: Chen, S.H.
Partner: UNT Libraries Government Documents Department

Evaluation of improved light water reactor core designs. Final progress report, September 1979. LWRCD-20

Description: The work conducted under this research project has developed information which supports in all respects the U.S. position evolved under the NASAP/INFCE programs with respect to the near and intermediate term potential for ore conservation in LWRs on the once-through fuel cycle. Moreover, in the even longer term, it has been confirmed that contention by Edlund and others that tight-pitch Pu/UO/sub 2/ PWR cores can achieve conversion ratios which may allow these reactors to provide a competitive energy source far into the ore-scarce post-2000 era.
Date: October 31, 1979
Partner: UNT Libraries Government Documents Department

Process applications for geothermal energy resources. Progress report

Description: Energy use characteristics of the major energy using industries in the US were examined. The pulp and paper industry was selected and a workshop held. Two analyses were performed of the potential for substituting geothermal energy for fossil fuel in specific pulp and paper plants. The lack of industry interest is discussed. (MHR)
Date: October 1, 1979
Partner: UNT Libraries Government Documents Department

Design window calculations for a constant q' lithium blanket comparing lithium and sodium coolants

Description: In previous work, a design window approach has been applied to a liquid metal cooled, stagnant lithium breeding blanket, where the cooling tubes are spaced such that they all have the same heat flux per unit length (constant q'). This report is partly supplemental in that is is a detailed clarification of the equations and assumptions used, including several refinements. However, it also includes documentation for a revised version of the WINDOW code used to generate the design windows, and (as an example of the usefulness of the design window approach) a comparison of lithium cooling to sodium cooling of this blanket. The results confirm the desirability of lithium as a coolant.
Date: August 1, 1979
Creator: Gierszewski, P.; Mikic, B. & Todreas, N.
Partner: UNT Libraries Government Documents Department

Searches for violation of muon number conservation

Description: The question of violation of muon number conservation is one which has occupied considerable attention and resources in recent years. The first generation of experiments at the medium energy accelerators has now been completed and the next generation of experiments is ready to begin. The history of muon number conservation is reviewed, including the reasons for the present belief that the conservation law may not be exact. The experiments that have been completed in the last few years are discussed. The new experiments that are being mounted and planned at several laboratories are discussed, and the relationship of these types of experiments to other studies, such as searches for neutrino oscillations, are considered.
Date: January 1, 1981
Creator: Redwine, R.P.
Partner: UNT Libraries Government Documents Department

Magnetotelluric interpretations in a crustal environment. Semi-annual report, 1 January 1978-30 June 1978. [MIT, January 1 to June 30, 1978]

Description: Crustal variations in the conductivity and resistivity of the earth cause great complications in the surface distribution of electric currents and fields. At low frequencies the crust can be treated as a thin sheet, and the crustal conductivity variations can be incorporated into the thin sheet conductance variation. In the first model developed in this thesis, the layer below the thin sheet is a layer of finite conductivity. Thus the thin sheet model consists of a thin conducting sheet of variable conductivity over a general layered medium. In the earth the resistive layer below the surface conductive sheet is represented by the lower crust. The resistivity of the lower crust underneath the ocean is expected to be different from the resistivity of the lower crust below the continents. This difference in the lower crust resistivity value is taken into account in the Generalized Thin Sheet model. In this model the thin sheet is treated as an anisotropic thin sheet with different (parallel) conductivity and (perpendicular) resistivity variations. Specific examples in which conductivity and resistivity vary only in one direction were studied. It was found that in a crustal environment, approximation being made, it is possible to get simple analytical solutions for E variations perpendicular to the strike direction. Electric fields measured at a point are influenced not only by the conductivity and the resistivity of the medium at the point of measurement, but also by the electrical properties of the medium a considerable distance away. The method of imbedding was developed in which fields close to the point of measurement are computed at close spacings, while fields farther away are determined at larger spacings. These methods were applied to modelling magnetotelluric measurements on the island of Oahu. 107 figures, 13 tables.
Date: June 1, 1978
Creator: Madden, T.R.
Partner: UNT Libraries Government Documents Department

Magnetotelluric interpretations in a crustal environment. Semi-annual progress report, June 1, 1977-December 30, 1977

Description: A generalized thin layer analysis is described which includes a conductive layer and a resistive layer into a single layer. The equations describing the thin layer effects are reviewed and examples of comparisons between thin layer and generalized thin layer calculations are shown. Implementation of multiple scale analysis to allow the handling of large models in reasonable fashion was investigated. Some tests of these ideas on one-dimensional models are described. (MHR)
Date: February 1, 1978
Creator: Madden, T.R.
Partner: UNT Libraries Government Documents Department

Input parameters to codes which analyze LMFBR wire wrapped bundles. Revision 1

Description: This report provides a current summary of recommended values of key input parameters required for ENERGY code analysis of LMFBR wire wrapped bundles. This data is based on the interpretation of experimental results from the MIT and other available laboratory programs.
Date: May 1, 1979
Creator: Wang, S.F. & Todreas, N.E.
Partner: UNT Libraries Government Documents Department