Evaluation of thermochemical models for particle and continuum simulations of hypersonic flowComputations are presented for one-dimensional, strong shock waves that are typical of those that form in front of a reentering spacecraft. The fluid mechanics and thermochemistry are modeled using two different approaches. The first employs traditional continuum techniques in solving the Navier-Stokes equations. The second approach employs a particle simulation technique (the direct simulation Monte Carlo method, DSMC). The thermochemical models employed in these two techniques are quite different. The present investigation presents an evaluation of thermochemical models for nitrogen under hypersonic flow conditions. Four separate cases are considered that are dominated in turn by vibrational relaxation, weak dissociation, strong dissociation and weak ionization. In near-continuum, hypersonic flow, the nonequilibrium thermochemical models employed in continuum and particle simulations produce nearly identical solutions. Further, the two approaches are evaluated successfully against available experimental data for weakly and strongly dissociating flows.
Document ID
19920065294
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Boyd, Iain D. (NASA Ames Research Center Moffett Field, CA, United States)
Gokcen, Tahir (Eloret Institute Palo Alto, CA, United States)