Effects of Bulk Viscosity, Vibrational Energy, and Rarefaction on Flow and Vorticity Fields around Simple Bodies at Hypersonic Speeds

Abstract

The discrepancy between Navier Stokes Fourier-based CFD and aero thermodynamic flight test data becomes noticeable from altitudes above 50 km. It is argued that this gap is due to the shortcomings of the conventional Navier-Stokes-Fourier model. To investigate the cause of the shortcomings, we revisited the derivation of the continuum models from the BoltzmannCurtiss kinetic equations for diatomic and polyatomic gases. We investigated the effects of bulk viscosity, vibrational energy, and rarefaction on the hypersonic flow around a twodimensional cylinder and supersonic flow past a cavity. In addition, we analyzed the flow field in detail using a new complete compressible vorticity transport equation including the bulk viscosity. ? 2022, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.