by Jiequan Li.

**Series:** 1999-20, Preprints

- MSC:
- 35L65 Conservation laws
- 35L67 Shocks and singularities
- 65M99 None of the above, but in this section
- 76N15 Gas dynamics, general

**Abstract:**

This paper is the continuation of Preprint 99-19.

We take into account the existence of global

continuous solutions of two-dimensional

gas expansion for compressible Euler equations

for the case 1 < $\gamma$ < 3. The flow is governed by

a partial differential of second order

in the phase space under irrotationality condition, which can be

further reduced to three inhomogenous linearly degenerate

equations. Then this conclusion is applied to solve the

problem that a wedge of gas expands into a vacuum and

analyze the occurence of shocks in the interaction of

four planar rarefaction waves.

**Keywords:**

two-dimensional gas expansion, globa