RANS simulation with transition prediction method on airfoil flows with laminar separation bubbles

In this paper, the transition prediction model of e^N method based on linear stability theory is introduced into the calculation of the two dimensional Reynolds-Averaged Navier-Stokes (RANS) equations in order to improve the accuracy of numerical simulation of flow around airfoil, especially for cases involving laminar separation bubbles. The detailed information of the boundary layer used for linear stability analysis is obtained from the RANS solver. e^N method based on linear stability theory is used to analyze this information and determine the transition position which is then returned into the RANS solver. The above steps are repeated until the transition position changes insignificantly. So it is an automatic progress of transition prediction. Numerical simulation results of flows respectively around S809 airfoil and NACA 66₃-018 airfoil, presented in Figs.3 through 9, Figs.11 through 14 and Tables 1 and 2, and their analysis confirm preliminarily indeed the validity of our method of calculation, particularly for the cases involving laminar separation bubbles.