ANALYSIS OF BI-STABLE BEHAVIOR OF SHALLOW THIN SPHERICAL SHELL APPLIED IN ADAPTIVE INLET

Adaptive inlet can adjust the capture area and throat area of an inlet by actively controlling the structural shape of the lip and internal wall, so as to enhance the inlet performances of fighters in a large speed domain. A bump inlet is a kind of advanced inlet, but its performance of off-design points is limited due to its unchangeable bump surface shape. Aiming at the problem, this article presents an idea of using a bi-stable configuration of the shallow thin spherical shell to adjust the shape of the bump surface to improve the inlet performance at different speeds. For the hinge supported shallow thin spherical shell, the existence condition of a bi-stable configuration is analyzed, and the effects of loading mode and position on the bi-stable behavior of the shell are studied, also the relations between shell parameters and driving loads, loading stroke and internal stress are developed at the stable configuration transition moment, to provide a design reference for the shape control of the bi-stable configuration of the shallow thin spherical shell and its application in an adaptive inlet.