A Numerical Algorithm for the Multidimensional, Multiphase, Viscous Equations of Interior Ballistics,

Abstract

A numerical method based on a linearized ADI(Alternating Direction Implicit) scheme is described in the context of the solution procedure for the nonlinear partial differential equations associated with an average two-phase (gas-solid), two-dimensional, fully viscous model of interior ballistics. This method was chosen because the linearization of the time-differenced equations within the temporal truncation error permits a non-iterative solution procedure for this implicit scheme, and the splitting of difference equations along the coordinate directions provides a block tridiagonal structure of the solution matrices. The implementation of the algorithm possesses several novel features: the algorithm is derived in the context of a moving coordinate system; the non-conservational form of the governing equations avoids both mass sources (which can be generated by grid motion) and singular solutions matrices (which can arise in regions on one-phase flow in a two-phase calculation); and finally, the Jacobian type matrices (which arise from the linearization process) are determined by numerical differentiation instead of the usual analytic calculations. This numerical scheme is encoded in the DELTA computer code. Verification of the DELTA algorithm is obtained by comparing simulations to an analytic solution of an isentropic core flow and to the two-dimensional results of an experiment.

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1985
Accession Number
ADP004942

Entities

People

  • J. A. Schmitt

Organizations

  • Ballistic Research Laboratory

Tags

DTIC Thesaurus Topics

  • Algorithms
  • Applied Mathematics
  • Ballistics
  • Coordinate Systems
  • Difference Equations
  • Differential Equations
  • Equations
  • Interior Ballistics
  • Mathematics
  • Partial Differential Equations
  • Simulations
  • Two Dimensional

Fields of Study

  • Mathematics

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)