论文标题
轨道空气动力学应用的气体表面相互作用模型的综述
A Review of Gas-Surface Interaction Models for Orbital Aerodynamics Applications
论文作者
论文摘要
对非常低的地球轨道(VLEO)(即450公里的高度)的新兴趣导致对准确环境表征和空气动力学预测的需求增加。虽然前者需要了解驱动热层中密度变化的机制,但后者也取决于残留气氛中的气体和暴露于流动的表面之间的相互作用。空气动力系数的测定受到了众多不确定性的特征,这些不确定性表征了在裸露的表面上发生的物理过程。在过去的60年中,已经生产了几种模型,目的是将精度与相对简单的实现相结合。在本文中,最受欢迎的模型已被选择和审查与轨道空气动力学应用相关的区分因素,以及与气束实验数据的理论一致性。更复杂的模型被忽略了,因为它们的提高精度通常伴随着计算时间的大幅度增加,这可能不适合大多数太空工程应用。为了清楚起见,在基于物理和散射核理论的气体表面相互作用模型之间引入了区别。物理模型类别包括硬立方体模型,软立方体模型和洗手间模型,而散射内核家族由麦克斯韦模型,诺西拉·赫尔布特·舍尔曼模型和cercignani-lampis-lord模型组成。关于本文的背景,已经讨论了每个模型的限制和资产。在可能的情况下,已经提供了评论,以帮助读者确定有关轨道空气动力学应用的气面相互作用科学的未来挑战。
Renewed interest in Very Low Earth Orbits (VLEO) - i.e. altitudes below 450 km - has led to an increased demand for accurate environment characterisation and aerodynamic force prediction. While the former requires knowledge of the mechanisms that drive density variations in the thermosphere, the latter also depends on the interactions between the gas-particles in the residual atmosphere and the surfaces exposed to the flow. The determination of the aerodynamic coefficients is hindered by the numerous uncertainties that characterise the physical processes occurring at the exposed surfaces. Several models have been produced over the last 60 years with the intent of combining accuracy with relatively simple implementations. In this paper the most popular models have been selected and reviewed using as discriminating factors relevance with regards to orbital aerodynamics applications and theoretical agreement with gas-beam experimental data. More sophisticated models were neglected, since their increased accuracy is generally accompanied by a substantial increase in computation times which is likely to be unsuitable for most space engineering applications. For the sake of clarity, a distinction was introduced between physical and scattering kernel theory based gas-surface interaction models. The physical model category comprises the Hard Cube model, the Soft Cube model and the Washboard model, while the scattering kernel family consists of the Maxwell model, the Nocilla-Hurlbut-Sherman model and the Cercignani-Lampis-Lord model. Limits and assets of each model have been discussed with regards to the context of this paper. Wherever possible, comments have been provided to help the reader to identify possible future challenges for gas-surface interaction science with regards to orbital aerodynamic applications.