Improving the aerodynamic force measurement system for the USQ gun tunnel

Abstract

The accurate landing of entry capsules on other planets and moons depends on accurate knowledge of the aerodynamic behavior of the landing vehicle. The problem is that at the hypersonic speeds that are experienced by entry capsules during atmospheric entry, it is very hard to predict the capsule's behavior. This project, The Measurement of Entry Capsule Aerodynamic Force Coefficient aims to improve the original aerodynamic force measurement system that is used in the University of Southern Queensland Gun Tunnel. After an analysis of the previous method of force measurement and a review of other force measurement systems a new system was designed for the Gun Tunnel. This will allow for the prediction of normal and axial forces on an entry capsule model, as well as the location of the centre of pressure. The first test run of this project aimed to identify the aerodynamic forces acting on the Japanese, MUSES-C Entry Capsule during a Mach 7 flow in the USQ Gun Tunnel. During this test only the axial force was measured. This force was then compared to a prediction based on a Newtonian Flow model.