VOLNA PACKADE AND NONHOMOGENEOUS DIFFERENCE METHOD FOR COMPUTING NONSTEADY-STATE MOTION OF COMPRESSIBLE CONTINUUM. PART I. NONHOMOGENEOUS METHOD

V. F. Kuropatenko, G. V. Kovalenko, V. I. Kuznetsowa, G. I. Mikhailova, B. K. Potapkin, G. N. Sapozhnikova
VANT. Ser.: Mat. Mod. Fiz. Rroc 1989. Вып.2. С. 9-18.

      We present physical and computational models designed to simulate numerically a nonsteady-state motion of cotinuum with respect to a number of physical processes. A nonhomogeneons difference method is examined for numerical integration of a system of conservation laws. The difference shemes used are explicit. We give difference equation stability conditions and some ways for adapting spatial grids to solutions.

      We describe a general organization of the VOLNA package designed to simulate numerically a nonsteady-state motion of continuum with respect to a number of physical processes. Package architecture, input and output data, data file structure, development and operation principles are described.

      Some results on accounting resonance effects in multigroup neutron calculations are presented. Two methods are examined: cross-section self-screening factor and subgroup methods. The ways are discussed for estimating resonance features of the weight function used to obtain cross-section resonance self-screening factors. The paper considers a more cost-effective method for accounting resonance effects which is involved in group constant setting and assoc i ted with a subgroup method.

      The paper describes macros extending Macro-11 Assembler capabilities for data structuring and description. Data structures are described by macro- instructions. Complicated structures are constructed hierarchicably buy introducing existing structures as their components. These are referenced with unique data structure names similar to predefined data type references in Pascal. Simple (number, symbol, logic) and complex (sets, files, records) data structures are allowed. Both conventional and optional records are possible.
      It is also possible to have various file and record superpositions. Several macroinstructions are developed to process data structures. Input data may be specified both in design and run-time stages.