Accession Number : AD0702666

Title :   THE CALCULATION OF THE FORMATION OF DISCONTINUITIES IN PLANAR AND SPHERICALLY-SYMMETRIC NONISENTROPIC FLOWS.

Descriptive Note : Technical information series,

Corporate Author : GENERAL ELECTRIC CO PHILADELPHIA PA SPACE DIV

Personal Author(s) : Gordon,Paul ; Scala,Sinclaire M.

Report Date : MAR 1970

Pagination or Media Count : 50

Abstract : The possibility of the occurrence of discontinuities in inviscid flows governed by the Euler equations is a well-recognized phenomenon, and artificial viscosity techniques have been developed to overcome the associated difficulties. In the paper, the following two questions were investigated: (1) Is it possible to utilize a numerical scheme for the inviscid equations, for both isentropic and nonisentropic flows, such that the stability of the method does not depend on an artificial viscosity effect, (2) Is it possible to have continuous nonisentropic, inviscid flows in which there are subsonic and supersonic regions. The results of three numerical studies indicate that the finite difference representation that was utilized to solve the Euler equations is stable, even in the presence of mathematical discontinuities, and that this stability is not due to what is commonly referred to as an artificial viscosity. Also, it was found that regions of varying entropy remain continuous, although mathematical discontinuities are formed at later times in the regions of constant entropy. (Author)

Descriptors :   (*FLOW FIELDS, NUMERICAL ANALYSIS), EQUATIONS OF MOTION, VISCOSITY, SUBSONIC FLOW, SUPERSONIC FLOW, INJECTION, MASS TRANSFER, PISTONS, EXPLOSIONS, ENTROPY, DIFFERENTIAL EQUATIONS

Subject Categories : Aerodynamics
      Numerical Mathematics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE