Accurate drag calculation by coupling automatic prediction of transition point to the Navier-Stokes method

In this paper, we couple automatic prediction of transition to the calculation of the Reynolds-Averaged Navier-Stokes (RANS) equations in order to improve the accuracy of drag prediction in our flow solver. The RANS solver calculates the surface pressure distribution of the airfoil and communicates as input data to the laminar boundary-layer method compute all of the boundary-layer parameters and then the simply e^N-database method determines new transition positions which given back to the RANS solver. So it is a automatic progress of transition prediction. This method is used to simulate the flow around the NLF0416 airfoil and the calculation results are in concordance with the experimental data.