Studies based on the numerical simulations are presented for hypersonic blunt body and normal shock flows involving thermo-chemical nonequilibrium and radiation phenomena. The internal energy relaxation processes of vibrational energy transfer, dissociation, and radiation are treated using a state-to-state kinetics approach. A set of dissociation studies are conducted for a nitrogen gas flow past a blunt body, and coupled physico-chemical and radiative processes are investigated for flow behind a shock wave. The surface heat flux on the body is determined through a rigorous kinetic theory algorithm for the calculation of statetostate transport properties, such that diffusion velocities and heat flux are accounted for in the dissipative processes in the flow. Contributions to heat flux are considered for heat conduction, thermal diffusion, mass diffusion, and diffusion of vibrational energy. For the Mach 19.83 conditions, thermal diffusion is the dominant contributor to surface heat flux, and vibrational energy diffusion is also found to be a significant contributor. Radiation modeling is performed using a state to state approach which incorporates procedures for vibrational-translational and vibrational-electronic energy exchange as well as state-specific dissociation. It is found that radiative emission is very sensitive to dissociation product concentrations, and the evolution of the macroscopic gas parameters is essentially governed by the behavior of most populated species in their ground electronic states. The radiation intensity is mainly governed by spontaneous emission processes, which in turn result in significant depletion in the population of N₂ in the excited B³П state.