Accuracy versus convergence rates for a three dimensional multistage Euler codeUsing a central difference scheme, it is necessary to add an artificial viscosity in order to reach a steady state. This viscosity usually consists of a linear fourth difference to eliminate odd-even oscillations and a nonlinear second difference to suppress oscillations in the neighborhood of steep gradients. There are free constants in these differences. As one increases the artificial viscosity, the high modes are dissipated more and the scheme converges more rapidly. However, this higher level of viscosity smooths the shocks and eliminates other features of the flow. Thus, there is a conflict between the requirements of accuracy and efficiency. Examples are presented for a variety of three-dimensional inviscid solutions over isolated wings.
Document ID
19890026221
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Turkel, Eli (NASA Langley Research Center Hampton, VA; Tel Aviv University, Israel)