Aerodynamic Heating Around Flare-Type Membrane Inflatable Vehicle in Suborbital Reentry Demonstration Flight

Abstract

A demonstration flight of an advanced reentry vehicle was carried out using a sounding rocket. The vehicle was equipped with a flexible (membrane) aeroshell deployed by an inflatable torus structure. Its most remarkable feature was the low ballistic coefficient that enables reduction in aerodynamic heating and deceleration at a high altitude. During the suborbital reentry, temperatures at several locations on a backside of the flexible aeroshell and inside the capsule were measured by means of embedded thermocouples. The aerodynamic heating behavior of the vehicle was investigated using the measured temperature history, in combination with a numerical prediction in which a flow-field simulation of the heating was conducted. In this flow-field simulation, both laminar flow and turbulent flow were assumed, and the deformation of the flexible aeroshell was considered. A thermal model of the capsule and membrane aeroshell was developed, and the heat flux profiles of the vehicle surface during aerodynamic heating were constructed based on the measured temperatures. The measured temperature data were found to be in reasonable agreement with the predicted data if the flow field near the capsule of the vehicle was assumed to be laminar, with a transition to turbulent flow near the membrane aeroshell.