Non‐Continuum Phenomena in Hypersonic Flow

Abstract

At high altitude in the trajectory of a hypersonic entry vehicle, the atmospheric density is low, leading to relatively infrequent intermolecular collisions. The low collision rate produces physical flow phenomena which cannot be predicted accurately using a continuum description. This chapter describes the most important of these non‐continuum phenomena for hypersonic flow analysis and the conditions under which they occur. A numerical technique for analysis of non‐continuum flows is described and its success demonstrated through comparison with measurements collected in laboratory and flight experiments, and with results generated using the continuum approach.