A singly-iterative second-order method of characteristics for unsteady compressible one-dimensional flows

Unsteady compressible and frictional pipe flows in the high subsonic range, especially near the choking condition, are delicate to handle with numerical methods. Even the well-established first-order characteristics method may not be accurate enough. This communication describes a procedure based on second-order interpolations using curved characteristics within each numerical space-time mesh. As only one level of iteration is needed, a considerable amount of computing time can be saved.