On an Artificial Boundary Condition for Compressible Inviscid Isentropic Flows and a Relation to the Thompson Boundary Condition(Scientific Computation and Numerical Analysis,<Special Issue>Joint Symposium of JSIAM Activity Groups 2008)

Abstract

Since the computational resources are finite, one must truncate the computational domain into finite when he/she simulates waves in an unbounded region. However this truncation gives rise to artificial boundaries and boundary conditions on such the artificial boundaries greatly affect the quality of the numerical solutions. In this paper restricting ourselves to compressible inviscid isentropic flows we derive an artificial boundary condition and an energy-type estimate under that condition. Futhermore the obtained boundary condition is shown to be equivalent to the well-known Thompson boundary condition.