A VARIATIONAL THEORY FOR ONE-DIMENSIONAL UNSTEADY COMPRESSIBLE FLOW -AN IMAGE PLANE APPROACH

Via a semi-inverse method of establishing generalized variational prin ciples, two families of variational principles and generalized variati onal principles for one-dimensional unsteady compressible flow in an i magine plane tau-Psi (defined by tau = t, Psi - path-function) have be en deduced. The calculation domain in the image plane has the regular form of rectangle, which gives much advantage of utilizing variational -based FEM or other direct variational methods such as Kantrovich-FEM method to solve the problem. (C) 1998 Elsevier Science Inc. All rights reserved.