NNW-HyFLOW高超声速流动模拟软件框架设计

NNW-HyFLOW在国家数值风洞（NNW）工程支持下，由风雷开源软件提供基础框架支撑，将建设成为基于结构/非结构混合网格，面向高超声速应用领域的国产自主工业CFD软件，具备高温气体热化学非平衡效应模拟及其相关气动力、气动热和气动物理特性计算分析等主要特色功能。本文从框架设计、数据结构、耦合方法、并行计算方法以及接口设计等方面对软件设计思想和框架特点进行了介绍，给出了求解器采用的理论模型、核心数值算法及其实现方法，结合HEG风洞试验、RAM-C飞行试验、Electre飞行试验以及航天飞机OV102飞行试验等典型算例开展了数值模拟。研究表明：NNW-HyFLOW具有底层代码复用、功能兼容性好、扩展能力强和接口灵活等优点，其当前测试版本已经具备了较好的高超声速非平衡流动数值模拟能力，在热化学非平衡效应及其影响的气动力特性、气动热环境和等离子体分布特性预测与评估方面，具有较高的数值计算精准度，初步满足了高超声速复杂飞行器高温非平衡流动数值模拟的需求。

Framework design of NNW-HyFLOW hypersonic flow simulation software

NNW-HyFLOW, supported by the National Numerical Windtunnel (NNW) Project, is developed as a domestic independent industrial CFD software for hypersonic flow simulation based on structural/unstructured hybrid grids. It is designed with the basic framework provided by the PHengLEI open source program, and can be used mainly for simulation of thermochemical nonequilibrium effects of high temperature gas, and calculation and analysis of related aerodynamic forces, aerodynamic heat and aerophysical characteristics. The design ideas and framework characteristics of the software are first introduced, including the framework design, data structure, coupling method, parallel computing method, and interface design. Then, the theoretical models, core numerical methods and their implementation employed by the solver are illustrated. Finally, numerical simulations using the software are conducted for several examples including the HEG wind tunnel experiment, RAM-C flight experiment, Electre flight experiment and flight experiment of space shuttle OV102 model. Results shows that the software has the advantages of less code reuse, good functional compatibility, strong expansion capabilities, and flexible interface. Additionally, its current test version already has a good simulation capability for hypersonic nonequilibrium flow, and can achieve high accuracy in prediction and evaluation of thermochemical nonequilibrium effects and their impact on aerodynamic forces, aerothermal environment and plasma distribution characteristics. It is proved that the software can meet the basic requirements of numerical simulation of high-temperature nonequilibrium flow for the complex hypersonic aircraft.