Effect of static shape deformation on aerodynamics and aerothermodynamics of hypersonic inflatable aerodynamic decelerator
Effect of static shape deformation on aerodynamics and aerothermodynamics of hypersonic inflatable aerodynamic decelerator
复制标题
静态形状变形对高超声速充气气动减速器气动和气动热力学的影响
DOI：
10.1016/j.actaastro.2017.03.019
复制
发表时间：
2017
影响因子：
3.5
通讯作者：
Y. Chao
中科院分区：
文献类型：
--
作者：
Jinghui Guo;G. Lin;Xueqin Bu;S. Fu;Y. Chao
充气式空气动力减速器（IAD）能够承载更重、更大的有效载荷，并在更高高度的着陆点选择上具有灵活性，在下一代空间运输系统中具有潜在的优势。然而，由于材料和结构装配的灵活性，IAD在进入大气时不可避免地会发生表面变形，从而改变飞行器周围的流场，导致空气动力学和空气热力学的变化。本文采用Menter的剪切应力输运（SST）湍流模型，通过求解可压缩Navier-Stokes方程，详细论证和分析了静态形状变形对叠合环面高超声速充气式气动减速器（HIAD）高超声速气动和气动热力学的影响。在进入时最大气动压力存在的情况下，通过结构建模得到了变形形状。数值结果表明，波动形状变形对流动结构有显著影响。特别是外侧前体表面的弯曲程度越高，导致了谷内的局部流动分离和再附着，从而产生了谷内压力上升而波峰处下降，谷内剪切应力和热流密度下降而波峰处上升的表面状况的显著波动。因此，与初始（未变形）形状相比，外部表面条件的差异更为明显，最大增加了379 pa、2224 pa和19.0 W/cm2，压力、剪切应力和热流分别增加了9.8%、305.9%和101.6%。此外，随着迎角的增大，气动特性和表面热效应发生变化，变形后的表面热效应与初始形状之间存在明显差异。本文研究的可变形HIAD模型揭示了更为剧烈的表面条件和变化的飞行空气动力学，这对结构材料的选择和飞控系统的设计至关重要。
The inflatable aerodynamic decelerator (IAD), which allows heavier and larger payloads and offers flexibility in landing site selection at higher altitudes, possesses potential superiority in next generation space transport system. However, due to the flexibilities of material and structure assembly, IAD inevitably experiences surface deformation during atmospheric entry, which in turn alters the flowfield around the vehicle and leads to the variations of aerodynamics and aerothermodynamics. In the current study, the effect of the static shape deformation on the hypersonic aerodynamics and aerothermodynamics of a stacked tori Hypersonic Inflatable Aerodynamic Decelerator (HIAD) is demonstrated and analyzed in detail by solving compressible Navier-Stokes equations with Menter's shear stress transport (SST) turbulence model. The deformed shape is obtained by structural modeling in the presence of maximum aerodynamic pressure during entry. The numerical results show that the undulating shape deformation makes significant difference to flow structure. In particular, the more curved outboard forebody surface results in local flow separations and reattachments in valleys, which consequently yields remarkable fluctuations of surface conditions with pressure rising in valleys yet dropping on crests while shear stress and heat flux falling in valleys yet rising on crests. Accordingly, compared with the initial (undeformed) shape, the corresponding differences of surface conditions get more striking outboard, with maximum augmentations of 379 pa, 2224 pa, and 19.0 W/cm2, i.e., 9.8%, 305.9%, and 101.6% for the pressure, shear stress and heat flux respectively. Moreover, it is found that, with the increase of angle of attack, the aerodynamic characters and surface heating vary and the aeroheating disparities are evident between the deformed and initial shape. For the deformable HIAD model investigated in this study, the more intense surface conditions and changed flight aerodynamics are revealed, which is critical for the selection of structure material and design of flight control system.