Blunt-body configurations are the most common geometries adopted for non-lifting re-entry vehicles. Hypersonic re-entry vehicles experience different flow regimes during flight due to drastic changes in atmospheric density. The conventional Navier-Stokes-Fourier equations with no-slip and no-jump boundary conditions may not provide accurate information regarding the aerothermodynamic properties of blunt-bodies in flow regimes away from the continuum. In addition, direct simulation Monte Carlo method requires significant computational resources to analyze the near-continuum flow regime. To overcome these shortcomings, the Navier-Stokes-Fourier equations with slip and jump conditions were numerically solved. A mixed-type modal discontinuous Galerkin method was employed to achieve the appropriate numerical accuracy. The computational simulations were conducted for different blunt-body configurations with varying freestream Mach and Knudsen numbers. The results show that the drag coefficient decreases with an increased Mach number, while the heat flux coefficient increases. On the other hand, both the drag and heat flux coefficients increase with a larger Knudsen number. Moreover, for an Apollo-like blunt-body configuration, as the flow enters into non-continuum regimes, there are considerable losses in the lift-to-drag ratio and stability.

中文翻译：

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基于模态间断Galerkin方法的带滑移和跳跃条件的Navier-Stokes-Fourier方程的近连续气体流动计算模拟

钝体构型是非起重再入车辆采用的最常见几何形状。由于空气密度的急剧变化，高超音速再入飞行器在飞行过程中会经历不同的流动状态。具有无滑移和无跳跃边界条件的常规Navier-Stokes-Fourier方程可能无法提供关于钝体在远离连续体的流动状态下的空气热力学性质的准确信息。此外，直接模拟蒙特卡洛方法需要大量的计算资源来分析近连续流状态。为了克服这些缺点，对具有滑移和跳跃条件的Navier-Stokes-Fourier方程进行了数值求解。为了达到适当的数值精度，采用了混合型模态间断Galerkin方法。针对具有不同自由流马赫数和克努森数的不同钝体构型进行了计算仿真。结果表明，阻力系数随着马赫数的增加而减小，而热通量系数增大。另一方面，阻力系数和热通量系数都随着更大的克努森数而增加。此外，对于类似阿波罗的钝体构造，当流体进入非连续状态时，升阻比和稳定性会损失很多。