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MIT LMFBR blanket research project. Quarterly progress report, July 1, 1977--September 30, 1977

Description: Irradiation experiments on Mockup 5B have been completed. A series of comparative calculations are underway on internal blanket variations. Preliminary results are presented. A fnal workup of the T/sub i/(n,p) Sc/sup 48/ and N/sub i/(n,p) Co/sup 58/ threshold traverses in Blanket Mockup 5B has been completed.
Date: January 1, 1977
Creator: Driscoll, M.J.
Partner: UNT Libraries Government Documents Department

MIT LMFBR blanket physics project progress report No. 7, July 1, 1975--September 30, 1976

Description: Work during the period was devoted primarily to a range of analytical/numerical investigations, including evaluation of means to improve external blanket designs, beneficial attributes of the use of internal blankets, improved methods for the calculation of heterogeneous self-shielding and parametric studies of calculated spectral indices. Experimental work included measurements of the ratio of U-238 captures to U-235 fissions in a standard blanket mockup, and completion of development work on the radiophotoluminescent readout of LiF thermoluminescent detectors. The most significant findings were that there is very little prospect for substantial improvement in the breeding performance of external blankets, but internal blankets continue to show promise, particularly if they are used in such a way as to increase the volume fraction of fuel inside the core envelope. An improved equivalence theorem was developed which may allow use of fast reactor methods to calculate heterogeneously self-shielded cross sections in both fast and thermal reactors.
Date: September 30, 1976
Creator: Driscoll, M.J. (ed.)
Partner: UNT Libraries Government Documents Department

MIT LMFBR blanket research project. Quarterly progress report, April 1-June 30, 1979

Description: In designing a plutonium-uranium core with thorium internal blankets there are several parameters that must be investigated to identify the design with the best performance. Choices include: the amount of moderation in the blanket, whether moderation is incorporated from the outset or added after an assembly is shuffled to the external blanket, and the cycle length both for the core and internal blanket assemblies. To investigate the effect of these parameters several core and blanket burnup analyses were performed.
Date: July 25, 1979
Creator: Driscoll, M.J.
Partner: UNT Libraries Government Documents Department

MIT LMFBR blanket research project. Final summary report

Description: This is a final summary report on an experimental and analytical program for the investigation of LMFBR blanket characteristics carried out at MIT in the period 1969 to 1983. During this span of time, work was carried out on a wide range of subtasks, ranging from neutronic and photonic measurements in mockups of blankets using the Blanket Test Facility at the MIT Research Reactor, to analytic/numerical investigations of blanket design and economics. The main function of this report is to serve as a resource document which will permit ready reference to the more detailed topical reports and theses issued over the years on the various aspects of project activities. In addition, one aspect of work completed during the final year of the project, on doubly-heterogeneous blanket configurations, is documented for the record.
Date: August 1, 1983
Creator: Driscoll, M.J.
Partner: UNT Libraries Government Documents Department

MIT LMFBR Blanket Research Project. Quarterly progress report, January 1-March 31, 1980

Description: During FY 1980 work is being carried out on the following subtasks: evaluation of the thermal/hydraulic/mechanical consequences of enhanced fertile and fissile capture rates at interfaces; development of simpler ways to estimate interface capture rate enhancement; particularization of the breed/burn internal/external blanket management scheme; and participation in the Large Core Code Evaluation Working Group (LCCEWG) program.
Date: May 31, 1980
Creator: Driscoll, M.J.
Partner: UNT Libraries Government Documents Department

Interfacial effects in fast reactors. [LMFBR]

Description: The problem of increased resonance capture rates near zone interfaces in fast reactor media has been examined both theoretically and experimentally. An interface traversing assembly was designed, constructed and employed to measure U-238 capture rates near th blanket--reflector interface in the MIT Blanket Test Facility. Prior MIT experiments on a thorium--uranium interface in a blanket assembly were also reanalyzed. Extremely localized fertile capture rate increases of on the order of 50% were measured immediately at the interfaces relative to extrapolation of asymptotic interior traverses, and relative to state-of-the-art (LIB-IV, SPHINX, ANISN/2DB) calculations which employ infinite-medium self-shielding throughout a given zone. A method was developed to compute a spatially varying background scattering cross section per absorber nucleus which takes into account both homogeneous and heterogeneous effects on the interface flux transient.
Date: May 1, 1979
Creator: Saidi, M.S. & Driscoll, M.J.
Partner: UNT Libraries Government Documents Department

Systems studies on the extraction of uranium from seawater

Description: This report summarizes the work done at MIT during FY 1981 on the overall system design of a uranium-from-seawater facility. It consists of a sequence of seven major chapters, each of which was originally prepared as a stand-alone internal progress report. These chapters trace the historical progression of the MIT effort, from an early concern with scoping calculations to define the practical boundaries of a design envelope, as constrained by elementary economic and energy balance considerations, through a parallel evaluation of actively-pumped and passive current-driven concepts, and thence to quantification of the features of a second generation system based on a shipboard-mounted, actively-pumped concept designed around the use of thin beds of powdered ion exchange resin supported by cloth fiber cylinders (similar to the baghouse flyash filters used on power station offgas). An assessment of the apparently inherent limitations of even thin settled-bed sorber media then led to selection of an expanded bed (in the form of an ion exchange wool), which would permit an order of magnitude increase in flow loading, as a desirable advance. Thus the final two chapters evaluate ways in which this approach could be implemented, and the resulting performance levels which could be attained. Overall, U/sub 3/O/sub 8/ production costs under 200 $/lb appear to be within reach if a high capacity (several thousand ppM U) ion exchange wool can be developed.
Date: November 1, 1981
Creator: Driscoll, M.J. & Best, F.R.
Partner: UNT Libraries Government Documents Department

Evaluation of tight-pitch PWR cores

Description: The impact of tight pinch cores on the consumption of natural uranium ore has been evaluated for two systems of coupled PWR's namely one particular type of thorium system - /sup 235/U/UO/sub 2/ : Pu/ThO/sub 2/ : /sup 233/U/ThO/sub 2/ - and the conventional recycle-mode uranium system - /sup 235/U/UO/sub 2/ : Pu/UO/sub 2/. The basic parameter varied was the fuel-to-moderator volume ratio (F/M) of the (uniform) lattice for the last core in each sequence. Although methods and data verification in the range of present interest, 0.5 (current lattices) < F/M < 4.0 are limited by the scarcity of experiments with F/M > 1.0, the EPRI-LEOPARD and LASER programs used for the thorium and uranium calculations, respectively, were successfully benchmarked against several of the more pertinent experiments.
Date: August 1, 1979
Creator: Correa, F.; Driscoll, M.J. & Lanning, D.D.
Partner: UNT Libraries Government Documents Department

Resonance region neutronics of unit cells in fast and thermal reactors

Description: A method has been developed for generating resonance-self-shielded cross sections based upon an improved equivalence theorem, which appears to allow extension of the self-shielding-factor (Bondarenko f-factor) method, now mainly applied to fast reactors, to thermal reactors as well. The method is based on the use of simple prescriptions for the ratio of coolant-to-fuel region-averaged fluxes, in the equations defining cell averaged cross sections. Linearization of the dependence of these functions on absorber optical thickness is found to be a necessary and sufficient condition for the existence of an equivalence theorem. Results are given for cylindrical, spherical and slab geometries. The functional form of the flux ratio relations is developed from theoretical considerations, but some of the parameters are adjusted to force-fit numerical results. Good agreement over the entire range of fuel and coolant optical thicknesses is demonstrated with numerical results calculated using the ANISN program in the S/sub 8/P/sub 1/ option.
Date: May 1, 1977
Creator: Salehi, A.A.; Driscoll, M.J. & Deutsch, O.L.
Partner: UNT Libraries Government Documents Department

LMFBR Blanket Physics Project progress report No. 2

Description: This is the second annual report of an experimental program for the investigation of the neutronics of benchmark mock-ups of LMFBR blankets. Work was devoted primarily to measurements on Blanket Mock-Up No. 2, a simulation of a typical large LMFBR radial blanket and its steel reflector. Activation traverses and neutron spectra were measured in the blanket; calculations of activities and spectra were made for comparison with the measured data. The heterogeneous self- shielding effect for $sup 238$U capture was found to be the most important factor affecting the comparison. Optimization and economic studies were made which indicate that the use of a high-albedo reflector material such as BeO or graphite may improve blanket neutronics and economics. (auth)
Date: June 30, 1971
Creator: Forbes, I.A.; Driscoll, M.J.; Rasmussen, N.C.; Lanning, D.D. & Kaplan, I. (eds.)
Partner: UNT Libraries Government Documents Department