Errors for calculations of strong shocks using an artificial viscosity and an artificial heat flux
Abstract
The artificial viscosity (Q) method of von NeumannRichtmyer is a tremendously useful numerical technique for following shocks wherever and whenever they appear in the flow. We show that it must be used with some caution, however, as serious Qinduced errors (on the order of 100%) can occur in some strong shock calculations. Three types of Q errors are investigated: (1) Excess Q heating, of which there are two types: (a) excess wall heating on shock formation, and (b) shockless Q heating; (2) Q errors when shocks are propagated over a nonuniform mesh; and (3) Q error in propagating shocks in spherical geometry. As a basis of comparison the Lagrangian formulation of von NeumannRichtmyer with Q = C0(2) rho l(2)(u sub x)(2) is used as the standard. Comparisons are made with other formulations.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 December 1985
 Bibcode:
 1985STIN...8632690N
 Keywords:

 Heat Flux;
 Shock Waves;
 Viscosity;
 Wave Propagation;
 Computation;
 Errors;
 Mathematical Models;
 Fluid Mechanics and Heat Transfer