Numerical investigation of the aerothermodynamics of lifting re-entry geometries

空间系统(包括发射和回收)及其相关技术具有广泛的社会经济效益，包括电信、农业、气候变化和救灾。对空间再入飞行器和高超声速飞行的空气热力学的了解仍然存在许多差距，包括显著的空气动力学特性对几何构型和飞行条件的依赖。对于升力再入飞行器来说尤其如此，这些飞行器在高层大气中飞行了很大一部分轨迹，在那里稀薄的流动、非平衡和化学效应变得相关。这一领域研究差距的主要原因是从实验和数值两方面研究这一问题的难度和高昂的成本。在过去的二十年里，计算能力和模拟技术的重大进步使得用最少的先验经验输入对这些现象进行数值研究变得越来越可行--提供了以前无法获得的数据和洞察力水平。本研究计划将使用升力再入流动的数值分析，以提高我们对复杂的气体动力学现象的理解，包括激波-边界层相互作用、流动分离和尾迹动力学。关键发现将有助于改进空间发射和回收系统的控制、热保护以及维修和重复使用战略。此外，这些发现还将有助于在超音速流动现象普遍存在的其他领域，如爆炸安全、工业气体处理和推进等领域的相关工作。由于CFD方法和计算能力的进步，可能会探索广泛的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数据。通过应用第一原理，他们将发展出更好的理论理解和有价值的半经验模型，使研究结果更普遍地适用。本研究人员过去的工作主要集中在低复杂性的二维和轴对称形状上，主要集中在高超声速层流流型上。高大气中3D升力再入几何的高超声速尾迹是这项过去工作的一个令人兴奋的进步。这项研究计划的长期目标是对复杂的三维气动热力特性有一个基本的了解，从而对高超声速尾迹动力学有一个更统一的理解，包括真实的气体效应。到五年的时间线结束时，HQP在这个项目中进行的工作将显著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，并增加提升再入飞行器的信心，从而具有科学、工程和政策意义。

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.