Three-dimensional Compressible Boundary Layer Calculation And Its Stability

In this paper the three-dimensional compressible boundary layer flow for a general fuselage with suction and a natural laminar flow (NLF) wing is investigated computationally by means of the boundary layer equation for a non-orthogonal curvilinear coordinate system. The stream function is modified and the nonlinear interaction between the boundary condition and the unknown variables is removed through the translation from wall normal velocity to a variable parameter of the governing equation. In this paper we develop a numerical technology of crosswise marching along divided segments. It can be used to compute the complicated boundary layer flow in which the sign of the crosswise velocity is changed for many times. Secondly, we applied the theory of parabolized stability equations into the three-dimension compressible boundary layer flow and derived the incompressible and compressible flow stability equations for a three-dimension non-orthogonal curvilinear coordinate system. We use the numerical method to solve these stability equations and analyze the stability features for a NLF wing.