A new method for estimating the first normal grid spacing in heat flux computations

The grid dependency is a crucial topic in the CFD computations of heat transfer. Furthermore, it is revealed that the first grid point spacing in the normal direction plays a key role in the computations. The grid resolution for accurate predictions of wall heat flux quantities does not only depend on Mach number and Reynolds number, but also depends on body characteristic length and the temperature. The present paper performs a systematic parametric study to analyze the influences from these parameters, and proposes a new approach to predict the required grid resolution. Numerical experiments are carried out to verify the proposed formulation.