Global solutions of shock reflection by large-angle wedges for potential flow

Abstract

When a plane shock hits a wedge head on, it experiences a reflection-diffraction process and then a self-similar reflected shock moves outward as the original shock moves forward in time. Experimental, computational, and asymptotic analysis has shown that various patterns of shock reflection may occur, including regular and Mach reflection. However, most of the fundamental issues for shock reflection have not been understood, including the global structure, stability, and transition of the different patterns of shock reflection. Therefore, it is essential to establish the global existence and structural stability of solutions of shock reflection in order to understand fully the phenomena of shock reflection. On the other hand, there has been no rigorous mathematical result on the global existence and structural stability of shock reflection, including the case of potential flow which is widely used in aerodynamics. Such problems involve several challenging difficulties in the analysis of nonlinear partial differential equations such as mixed equations of elliptic-hyperbolic type, free boundary problems, and corner singularity where an elliptic degenerate curve meets a free boundary. In this paper we develop a rigorous mathematical approach to overcome these difficulties involved and establish a global theory of existence and stability for shock reflection by large-angle wedges for potential flow. The techniques and ideas developed here will be useful for other nonlinear problems involving similar difficulties.

Authors

Gui-Qiang Chen

Department of Mathematics
Northwestern University
Evanston, IL 60208-2730
United States
and
Mathematical Institute
University of Oxford
0X1 3LB, Oxford
United Kingdom
and
School of Mathematical Sciences
Fudan University
Shanghai 200433, PRC

Mikhail Feldman

Department of Mathematics
University of Wisconsin
Madison, WI 53706-1388
United States