Accurate prediction of the development of the boundary-layer thickness is essential in designing hypersonic wind tunnels and nozzles using computational fluid dynamics(CFD). The nozzle boudnary-layer thickness becomes extremely thin at the throat region. Immediately downstream of the throat, as the flow begins to expand, the boundary-layer thickness grows rapidly. Estiamtes of grid requirements for resolving the turbulent boudnary layer in the throat region using a Navier-Stokes solver have shown that the number of grid points or grid stretching factor is an order of magnitude greater than what is needed to resolve the nozzle exit region. Approximately 80percent of the total time taken to resolve the flow field in the entire nozzle is consumed at the throat region. In the present study, the law of the wall and the law of the wake are used to resolve the inner part of the boundary layer instead of integrating to the surface to improve the execution time nad relax the grid clustering requirements.
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