Numerical investigation of the aerothermodynamics of lifting re-entry geometries

空间系统（包括发射和回收）及其相关技术具有全面的社会经济惠益，包括对电信、农业、气候变化和救灾的惠益。对空间再入飞行器和高超音速飞行的气动热力学的理解仍有许多空白，包括显著的气动力特征对几何构型和飞行条件的依赖性。对于升力式再入飞行器来说尤其如此，因为其轨道的很大一部分是在高层大气中度过的，在那里稀薄气流、非平衡和化学效应变得相关。在这一领域的研究差距的主要原因是困难和高成本的实验和数值研究的问题。在过去的二十年中，计算能力和模拟技术的重大进步使得以最小的先验经验输入来数值地研究这些现象变得越来越可行-提供了以前无法获得的数据和洞察力。本研究计划将使用数值分析的升力再入流，以提高我们对复杂的气体动力学现象，包括激波边界层相互作用，流动分离，和尾流动力学的理解。关键的发现将有助于改进航天发射和回收系统的控制、热保护、维修和可重复使用战略。此外，这些发现将有利于在其他领域，如爆炸安全，工业气体过程，推进超音速流动现象无处不在的相关努力。由于CFD方法和计算能力的进步，可以探索各种飞行条件和几何形状。HQP将产生高质量的数值数据集和观测结果。通过第一原理的应用，他们将开发更好的理论理解和有价值的半经验模型，使研究结果更普遍适用。本研究员过去的工作集中在二维和轴对称形状的低复杂性，主要集中在高超音速层流状态。高大气层三维升力再入体的高超音速尾流是对以往工作的一个令人兴奋的进展。 这项研究计划的长期目标是从根本上了解复杂的三维气动热力学流动特征，从而对高超音速尾流动力学（包括真实的气体效应）有更统一的认识。到五年时间轴结束时，HQP在该计划中进行的工作将大大提高我们对再入和几个邻近领域所涉及的气体动力学现象的理解。这项工作将开辟新的研究领域，改进优化和飞行器设计工作，并增加对提升重返大气层飞行器的信心，从而具有科学，工程和政策影响。

Space systems (including launch and recovery) and their associated technologies have comprehensive socio-economic benefits, including to telecommunications, agriculture, climate change, and disaster relief. Understanding of the aerothermodynamics of space re-entry vehicles and hypersonic flight still contains many gaps, including the dependence of salient aerodynamic features on geometric configuration and flight conditions. This is particularly true for lifting re-entry vehicles which spend a significant portion of their trajectory in the upper atmosphere where rarefied flow, non-equilibrium, and chemistry effects become relevant. The primary reason for the research gaps in this area has been the difficulty and high cost of studying the problem both experimentally and numerically. In the past two decades, major advances in computing power and simulation techniques have made studying these phenomena numerically, with minimal a priori empirical inputs, increasingly feasible - providing data and levels of insight previously unavailable. The present research program will use numerical analysis of lifting re-entry flows to improve our understanding of complicated gas dynamic phenomena, including shock-wave boundary layer interactions, flow separation, and wake dynamics. Key findings will enable improved control, thermal protection, and repair and reusability strategies in space launch and recovery systems. In addition, these findings will benefit related efforts in other domains such as explosion safety, industrial gas processes, and propulsion where supersonic flow phenomena are ubiquitous. Thanks to advancements in CFD methodologies and computing power, a wide range of flight conditions and geometries may be explored. HQP will produce high-quality numerical datasets and observations. Through the application of first principles, they will develop improved theoretical understanding and valuable semi-empirical models making findings more generally applicable. Past work by the present investigator has focused on 2D and axisymmetric shapes of low complexity, primarily focused on the hypersonic laminar flow regime. The hypersonic wake of 3D lifting re-entry geometries in the high atmosphere presents an exciting advancement to this past work. The long-term objective of this research program is to gain a fundamental understanding of complex three-dimensional aerothermodynamic flow features leading to a more unified understanding of hypersonic wake dynamics, including real gas effects. By the end of the five-year timeline, the work conducted by HQP in this program will have significantly improved our understanding of gas-dynamic phenomena involved in re-entry and several adjacent fields. This work will open up new areas of inquiry, improve optimization and vehicle design efforts, and increase confidence in lifting re-entry vehicles, thereby having scientific, engineering, and policy implications.