The Outflow Boundary Condition in Numerical Time Integration of Advective Equations

Abstract

Tests are made on the methods of estimating outflow boundary values when simple linear and non-linear advective equations are solved numerically by use of finite difference. Of nine schemes examined, four methods seem to be useful ; they are Methods 5, 6, 7 and 9 described in section 3. Errors occurring due to improper setting the outflow boundary condition propagate backward into the domain with slightly higher speed than that of advection speed.