A Study on the Impact of Radiative Heat Transfer for Hypersonic Nonequilibrium Flows over a Cylinder

Hypersonic flow over a cylinder is modeled using the finite volume method to solve the Navier-Stokes equations, including Park’s two-temperature model for chemical dissociation. The main focus of this work is to carry out a comparative analysis of the thermodynamic nonequilibrium properties along the flow stagnation line, and obtain the infrared spectrum of radiative heat flux at the stagnation point of the cylinder using a line-by-line approach. The spectrum of radiative heat flux at the stagnation point of the cylinder are obtained using NEQAIR numerical code, considering the NEQAIR and HITRAN transitions. In hypersonic flow conditions, it is possible to observe the occurrence of thermodynamic nonequilibrium through the magnitude difference of the translational-rotational and vibrational-electronic temperature modes inside the shock layer forming upstream of the cylinder. Analyses of the thermodynamic nonequilibrium effects are performed, considering the excitation state of the temperature modes, in addition to the chemical effects of dissociation and exchange of molecules and atoms present in the mixture.