The equations of 1-D compressible flow with area change in a Lagrangian particle description

Abstract The equations for one-dimensional compressible flow with area change are derived in the Lagrangian particle description for the first time. A simple finite difference code based on the α method is used to obtain the solution for three problems; the passage of a rarefaction wave through an area reduction and an area enlargement, and the passage of a shock wave through an area enlargement. Results are presented in the form of Lagrangian particle trajectories as well as spatial distributions of pressure, velocity and density.