Design of laminar supercritical airfoils based on Navier-Stokes equations

This paper aims to develop a suit of design methods and tools for laminar supercritical airfoils, based on high-fidelity computational fluid dynamics (CFD). The reliable transition perdition method, efficient inverse design and global optimization design methods are regarded as three key issues, which are addressed in this paper. The automatic transition prediction method coupling Navier- Stokes equations flow solver and e^N linear stability analysis method is applied to the design and analysis of the laminar supercritical airfoils; inverse design and optimization design methods based on kriging surrogate model is developed to attain favorable pressure gradient while reducing wave drag; efficient optimization based on kriging model and an improved EI (expected improvement) method is developed for finding the global optimum. Two laminar supercritical airfoils have been designed for cruise Mach number of 0.72 and 0.74, and design lift coefficient of 0.6. The results show that about 55-60 laminar flow regions on upperand lower surface have been attained.