Comparative study of various approaches for modeling transitional hypersonic rarefied gas flows over blunt bodies

Abstract

The hypersonic rarefied gas flow over blunt bodies in the transitional flow regime, typical of the reentry flight of space vehicles at altitudes higher 90-100 km, is investigated. As an example, the problem of hypersonic flows over long blunt wings and axisymmetric bodies is considered. It is analyzed in a wide range of the free stream Knudsen number by using various approaches: the continuum approach-numerical and analytical solutions, the direct simulation Monte Carlo method and the direct numerical solution of the Boltzmann kinetic equation with the S-model collision integral. The efficiency, domain of applicability, advantages and disadvantages of various approaches in the transitional flow regime are considered. © 2012 American Institute of Physics.