In this investigation, Direct Simulation Monte Carlo Method is used to compute the surface properties of inflatable aerodynamic decelerators (IAD) applied for the reentry, recovery, and reuse of cubeSats. Surface properties calculation is of fundamental importance for flexible thermal protection system materials selection that withstand the harsh reentry environment. Furthermore, simulations are extremely important to detect possible hot spots at the IAD before design and flight. In this work, three IAD configurations are exposed to a rarefied hypersonic flow with freestream conditions that correspond to those found at reentry conditions at 105 km altitude. All geometries are assumed to be axisymmetric and have a maximum radius of 0.3 m from the center line to the shoulder edge. The main differences between the geometries are the angle between the IAD and cubeSat body and the IAD curvature for geometry 3. According to the results, all IAD geometries are effective in protecting the cubeSat during the reentry phase. It is shown that the IAD geometry has a significant influence on the heat transfer, pressure, and skin friction coefficient distribution over the flexible heat shield. The maximum heat transfer coefficient computed for geometry 1, 2, and 3 is 0.90, 0.97, and 0.84, respectively.

中文翻译：

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用于立方体卫星再入和回收的充气气动减速器：表面特性


在这项研究中，直接模拟蒙特卡罗方法用于计算用于立方体卫星再入、回收和再利用的充气气动减速器 (IAD) 的表面特性。表面特性计算对于灵活选择能够承受恶劣再入环境的热防护系统材料至关重要。此外，模拟对于在设计和飞行之前检测 IAD 可能的热点非常重要。在这项工作中，三种 IAD 配置暴露在稀薄的高超音速气流中，其自由流条件与 105 公里高度的再入条件相对应。所有几何形状均假定为轴对称，并且从中心线到肩部边缘的最大半径为 0.3 m。几何形状之间的主要区别在于 IAD 和立方体卫星主体之间的角度以及几何形状 3 的 IAD 曲率。根据结果，所有 IAD 几何形状都可以在再入阶段有效保护立方体卫星。结果表明，IAD 几何形状对柔性隔热罩上的传热、压力和表面摩擦系数分布有显着影响。计算得出的几何形状 1、2 和 3 的最大传热系数分别为 0.90、0.97 和 0.84。