Supercritical Airfoil, Wing Fixed Regular And Non-steady Flow Numerical Simulation,

Supercritical wings have been widely used on modern civil airplanes and military transports due to their higher aerodynamic efficiency, higher cruising Mach number and greater relative thickness. Accurate calculation of aircraft steady and unsteady aerodynamics and flutter characteristics, especially in the transonic speed range is a crucial problem for aircraft designers. It is very important for us to develop an efficient, accurate, robust Navier-Stokes/Euler flow solver that could be used to study transonic steady and unsteady flowfields.The transonic steady/unsteady Navier-Stokes/Euler flow solvers based on AUSM+ scheme have been developed in this dissertation. The structured grids are generated using transfinite interpolation. A cell-centered finite volume approach is used. The in viscid flux is discretized by AUSM+ scheme. The viscid flux is discretized by second-order central difference scheme. Baldwin-Lomax turbulence model is implemented in Navier-Stokes flow solver. For steady-state calculations, a four-stage Runge-Kutta scheme with convergence acceleration techniques such as local-time stepping and implicit residual smoothing is used. For unsteady-state calculations, Jameson's dual-time method is used.To confirm the validity, effectivity and reliability of developed flow solvers based on AUSM+ scheme, test cases of steady/unsteady transonic flow of NACA0012 airfoil and ONERA M6 wings are investigated first. Furthermore, numerical simulations for steady or unsteady transonic flow of RAE2822 and DFVLR-R2 supercritical airfoils and a supercritical wings are investigated. The numerical results are in good agreement with experimental data where available. Finally, the 2D unsteady Navier-Stokes flow solver is coupled with two-degree-of-freedom flutter motion equation in time domain to investigate the flutter characteristics of several supercritical airfoils.The investigation in this dissertation shows the capabilities of AUSM+ scheme, such as the exact resolution of shock, low numerical dissipation, simple and requiringless computational effort. The successful applications on supercritical airfoils and wings show that the present flow solvers based on AUSM+ scheme are of valuable and promising in practical application.