Accession Number : AD0650544

Title :   A CLASS OF SCIENTIFIC APPLICATIONS ON LARC,

Corporate Author : DAVID TAYLOR MODEL BASIN WASHINGTON D C APPLIED MATHEMATICS LAB

Personal Author(s) : Cuthill,Elizabeth ; Schot,Joanna Wood

Report Date : JUN 1958

Pagination or Media Count : 23

Abstract : Large data handling and storage problems are encountered in the preparation of codes for the solution of systems of elliptic partial difference equations on a three-dimensional network when the number of points is of the order of 50 x 50 x 50. The solution of such systems of equations comprises one part of FLAME, a multigroup burnout code for LARC prepared for the prediction of the time-dependent neutron distribution in a nuclear reactor. Seven-point difference equations are used. Coefficients in these difference equations are permitted to vary pointwise so that solutions for non-homogeneous reactors can be obtained. The form in which the coefficients are stored is a function of the numerical method used. Efficient methods of solution require fast access storage for the order of 1,000,000 values. This is possible using the LARC drums. On LARC, computation in the central computer can be performed concurrently with data-transfer operations between drums and core storage. Because of the relative speeds of these functions, it is shown that with the proper choice of method an almost perfect balance between computation time and data-transfer time can be achieved. (Author)

Descriptors :   (*DIGITAL COMPUTERS, DATA PROCESSING), (*NEUTRON TRANSPORT THEORY, COMPUTER PROGRAMS), (*REACTOR KINETICS, MATHEMATICAL PREDICTION), NEUTRON FLUX, DATA TRANSMISSION SYSTEMS, DIFFERENCE EQUATIONS, DATA STORAGE SYSTEMS

Subject Categories : Computer Programming and Software
      Computer Hardware
      Fission Reactor Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE