Extended Continuum Models for Transient and Rarefied Hypersonic Aerothermodynamics

设想用于未来国防应用的高超音速飞行器的空气动力学设计，以及英国合作的行星探索计划（例如欧空局极光计划中的ExoMars），由于强烈的粘性效应，（非常高的局部加热率和激波/激波相互作用）、混合密度流场的稀疏现象和高温的真实气体效应（振动激发、离解和电离）。传统的流体动力学通常不适用于许多气动热力学的情况，而统计分子动力学计算量太大。为了解决这两个问题，我们建议部署扩展的流体动力学旁边的一个新的连续流体描述的非平衡热化学，包括稀疏和表面催化。扩展的流体动力学包括高阶添加到Navier-Stokes模型，纠正稀疏。它结合了连续流模型的计算效率和在近平衡条件下简化为传统的Navier-Stokes模型的主要优点。这是达雷斯伯里实验室与斯特拉斯克莱德大学和沃里克大学之间的一项新的合作，目的是建立英国在高速混合密度空气动力学建模方面的新能力。这是一个与国防部国防科学技术实验室（Dstl）的联合拨款计划提案，并得到MBDA和FGE的额外支持。Dstl将提供实验和计算数据来帮助验证我们的模型。他们还将与申请人共同举办为期一天的高速流动建模公开研讨会，该研讨会将作为讨论英国高速流动研究界未来发展和方向的论坛。

The aerodynamic design of hypersonic vehicles envisaged for future defence applications, and UK-partnered planetary exploration plans (e.g. ExoMars in ESA's Aurora programme), is a major challenge due to the strong viscous effects (very high local heating rates and shock/shock interactions), the rarefaction phenomena characteristic of mixed-density flowfields, and the real-gas effects of high temperature (vibrational excitation, dissociation and ionization). Conventional fluid dynamics is often unsuitable for many aerothermodynamic situations, while statistical molecular dynamics is computationally too intensive. To address these twin problems we propose deploying extended hydrodynamics alongside a new continuum-fluid description of the non-equilibrium thermochemistry that incorporates both rarefaction and surface-catalycity. Extended hydrodynamics comprises high-order additions to the Navier-Stokes model that correct for rarefaction. It combines the computational efficiency of continuum-flow models with the major advantage that it reduces to the conventional Navier-Stokes model in near-equilibrium conditions.This is a new collaboration between Daresbury Laboratory and Strathclyde and Warwick Universities with the goal of building a new UK capability in high-speed mixed-density aerodynamic modelling. It is a Joint Grant Scheme proposal with the MoD's Defence Science and Technology Laboratory (Dstl), with additional support from MBDA and FGE. Dstl will provide experimental and computational data to help validate our models. They will also co-host with the applicants a one-day open workshop on high-speed flow modelling, which will act as a forum to discuss the future growth and direction of the UK high-speed flow research community.