Wing-body Viscous Flow Field Ns Equation, Numerical Simulation,

It' s necessary for computational fluid dynamics(CFD) to provide exact, efficient, applied aerodynamic data and tools for analyzing flow-fields. Only making use of Euler equations to simulate the flow-fields is untimeliness, the tendency is solving N-S equations with algebraic methods, so as to simulate viscous effection and offer more exact information about flow-fields.In recent thirty years, with the development of velocity potential methods, methods of solving Euler equations and the numerical value methods of Euler equations and boundary layer equations coupling iterative, it could realistically simulate the true flow-fields, partly replace the experimental research and play a crucial role in engineer applications research. Whereas the methods above are faultiness to some complicated viscous circle-flow problems, such as, the mutual interferer of strong shock wave and boundary layer, the isolating flow of large attack angle and the form and development of votex, etc. As a result, numerically solving N-S equations is developed step by step.It is possible to solve N-S equations with the improvement of the hardware and software in computer fields, and the development of numerical methods in computational fluid dynamics (CFD). To numerically solve N-S equations, the present work is mainly focused on the following aspects:1. Solving the elliptic grid generation together with an algebraic method marching along the normal-to-wall direction, viscous grids around complex geometries are generated. The boundary-layer grids with the algebraic method is othogonality and easy to control the distance to the wall. According to the Hilgenstock, the source items are calculated to control the othogonality and spacing of grid lines to boundaries.2. The spatially discrete schemes about the convection terms of the N-S equations: the centered difference with artificial viscos by Jameson, is studied. In order to apply the central scheme to higher Mach number flows, the sensor about pressure are modified with some TVD-like properties, as a result, it decrease the untruth numerical vibration effectively, and broaden the application extent of the centered difference format.3. Explicit four stages modified Runge-Kutta scheme is used to solve 3-D unsteady compressible N-S equations. The explicit method is widelyused for its simpleness and little memory consumed with local time step and variable coefficients implicit residual smooth to accelerate the convergence procedure.4. Choose and solve algebraic Baldwin-Lomax turbulent model.Many test cases are calculated to verify the above studies. Such as Lann wing, F4 wing, M6 wing, TND wing-body standard model, and F4 wing-body model. The results show the computing results match the experimental results very well.