An Investigation of Base Flow of a Circular Cylinder at Hypersonic Speeds

Abstract

Flows immediately behind bodies, often known as base flows, have been investigated by various researchers under various atmospheres and flow conditions at hypersonic speeds [1]. From the experimental point of view, one major limitation of the previous studies is that the data are usually limited to low enthalpy based ‘cold’ wind tunnel results where temperatures are not sufficiently high enough to drive real gas effects such as chemical reactions. There are some high enthalpy data available but generally, the data is sparse. Apart from the experiments, there are high enthalpy based computational results available which cover real gas effects, but these results are often validated with low enthalpy results, sometimes showing inconsistency in validation. Similarly, the efficacy of existing theories based on perfect gas are also examined using such ‘low enthalpy’ data. It is therefore worthwhile to examine the suitability of these theories and computations covering a broad range of flow conditions from low to sufficiently high enthalpy.