| Drag-reducing is an important issue and must be considered and solved in the research and development of hypersonic vehicles. Reduce drag of the hypersonic flight means that aircraft itself can carry more fuel and payload.Numerical simulation for hypersonic blunt of different configurations of the drag-reducing design is utilized to calculate the resistance of different states by using Euler and N-S equations. Especially for two kinds of drag-reducing designs, making a channel-configuration and adding an air-spike before the hypersonic configurations. Only the channel-configuration height and air-spike length and shape are paid attention. These two kinds of drag-reducing design configuration of the drag reduction effect and laws are summed up by analyzing and comparing the Fluent's calculation results and program calculation results. The relevant laws and conclusions are given after a detailed analysis to the calculation results.Firstly, the finite-volume method based on Jameson cell-centered scheme is applied to solve the two-dimensional Euler equations and N-S equations, and the Explicit Runge-kutta time stepping for the time marching.N-S equations based on Spalat-Allmaras One-Equation turbulence model is employed to simulate turbulent flows. Local time-stepping and implicit residual smoothing are applied to accelerate the solution for problems. Computational results agree well with experimental data. Secondly,the program capacity in this paper is compared with the Fluent software to determine the technical feasibility used in the drag-reducing program analysis. Finally, inviscid unstructured grid for Euler equations and viscous structure grid for N-S equations were generated by using Gridgen. In different states, the resistance of different drag-reducing designs configurations of blunt head hypersonic body shape is calculated by the program in this paper and Fluent software. The relevant laws and conclusions are given after a detailed analysis to the calculation results.
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