关键词: 多维对流通量重构；非结构网格；气动热；主方向

Abstract: In order to research the effects of different principle direction defined methods based on the multidimensional inviscid flux reconstruction on the stability of shock wave and pressure field， the analysis for the results in which the principle direction defined method based on Cartesian directions， density gradient and pressure gradient indicates that the non-physical ‘zigzag’ pressure contour occurs in the flowfield when the principle direction only relying on the gradient of physical quantities. In order to avoid this nonphysical phenomena， a new hybrid method based on pressure function is employed to define the principle direction. The simulation results for cylinder with single cell and ten rows of spanwise cells show that the hybrid method has better performance than other methods. The developed hybrid method not only eliminates the carbuncle phenomenon which occurs in the result solved by the principle direction based on Cartesian directions， but also removes the pressure contour ‘zigzag’ phenomenon which occurs in the result solved by the principle direction based on the gradient of density or pressure. The relative error of heat flux at stagnation point is 29.2% for the grid-align scheme by comparing with the result of structured grid solver， while this data is 4.0% for the multidimensional scheme by hybrid principle defined method. Therefore， it shows that the surface heat flux evaluated by the hybrid defined method for principle direction is reasonable.

Key words: Multidimensional inviscid flux reconstruction；Unstructured grid；Aero-heating；Principle direction