发表机构
Hong Kong University of Science and Technology; Northwestern Polytechnical University; HKUST Shenzhen Research Institute（香港科技大学; 西北工业大学; 香港科技大学深圳研究院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文将UGKWP方法扩展至带基元反应的多尺度混合气体流动，通过波粒解耦、宏观化学源项处理等方式改进，经高超声速圆柱、激波结构及三维侧喷算例验证，与DSMC结果吻合，具备多尺度多物种反应流动计算能力。
AI 中文摘要
近空间中的高超声速流动常耦合连续-稀薄多尺度效应与有限速率化学过程。本文将UGKWP方法扩展至带单一基元反应的多尺度混合气体流动。在UGKWP方法中，流体动力学波用于描述近平衡分布函数，数值粒子用于非平衡分布函数的演化；由特征积分解引导的波与粒子间的自适应转换，以及将dt作为观测尺度引入通量的操作，使该方法在涉及复杂物理的多尺度问题中取得成功。本研究中，并未依赖针对整个分布函数的综合反应动力学模型，而是先在宏观层面计算化学源项，再将其纳入波粒更新过程，同时在本研究考虑的单原子设定中，自由输运粒子保持化学非活性。该方法利用了波粒解耦的建模优势，便于扩展至更复杂的化学反应。此外，本文针对物种数大于2的多物种效应，开发了先进多物种动力学模型的近似扩展形式。通过在宽努森数范围（涵盖化学惰性、正向放热、正向吸热及dE=0条件）下的高超声速圆柱流动，以及具有热上/下游平衡态的激波结构，对当前UGKWP方法进行了评估，在混合气体流场、物种摩尔分数及壁面量方面均与DSMC结果吻合。进一步模拟了钝锥上的三维侧喷流动，以展示当前代码的三维计算能力。
英文摘要
Hypersonic flows in the near space often couple continuum-rarefied multiscale effect with finite-rate chemistry. This paper extends the UGKWP method to multiscale gas mixture flows with a single elementary reaction. In the UGKWP method, hydrodynamic waves are employed to describe near-equilibrium distribution functions, and numerical particles are used for the evolution of nonequilibrium ones. The adaptive conversion between waves and particles, guided by the characteristic integral solution, together with the introduction of dt into the flux as an observation scale, has enabled the UGKWP method to succeed in many multiscale problems involving complex physics. In this work, rather than relying on a comprehensive reactive kinetic model for the entire distribution function, chemical source terms are first evaluated at the macroscopic level and then incorporated into the wave-particle update, while free-transport particles are kept chemically inactive in the monatomic setting considered here. This approach leverages the modeling advantages of wave-particle decoupling, facilitating extension to more complex chemical reactions. Moreover, an approximate extension of an advanced multispecies kinetic model is developed in this work for multispecies effect with species number larger than two. The present UGKWP method is assessed for the Zeldovich-type reaction O2+N=NO+O through hypersonic cylinder flows over a wide Knudsen number range, covering chemically inert, forward exothermic, forward endothermic and dE=0 conditions, and through shock structures with hot upstream/downstream equilibrium states. Agreement with DSMC is obtained for gas mixture flow fields, species mole fractions and wall quantities. A three-dimensional side jet flow over a blunt cone is further simulated to demonstrate the three-dimensional capability of the present code.
