三维可压缩多相反应复杂流动的界面演变精细模拟方法研究

超声速燃烧技术是高超声速技术领域的核心，对超声速燃烧过程的深入理解是该领域创新研究的重要基础。其中最具挑战的是如何真实考虑化学反应多相流在界面附近的物理化学性质变化，并准确描述燃料界面的运动和演化，目前国内外研究很少涉及。为解决上述问题，本项目拟发展复杂外形下界面拓扑结构发生合并、破碎等变化的高精度数值模拟技术。推导考虑粘性、表面张力、相变、化学反应等因素的界面间断关系，建立复杂物理特性和热力学特性下多相界面条件的数学模型，完善对复杂现象的精细化模拟能力，有利于准确高效地求解激波、化学反应流与液滴作用下带来的相变问题。将虚拟流体方法创新应用于三维可压缩多相化学反应复杂流动的数值模拟，开发大规模科学计算中界面演变的精细化仿真平台CA-HIFI，完成数值模拟方法的有效性验证与应用。本项目使用的虚拟流体方法可以为超声速流场中燃料喷注混合增强等难题提供技术支持，目前尚未发现该方法的工程化应用实例。

Supersonic combustion technology is the core of hypersonic technology. An in-depth understanding of supersonic combustion process plays an important role for innovative research in this field. The most challenging task is to faithfully take the physical and chemical properties of reacting multiphase flows into consideration, and accurately describe the motion and evolution of fuel interfaces. It is rarely involved in domestic and international research at present. In order to solve this problem, this project aims to develop the higher-order accurate numerical technique to treat interface topology changes involving mergence and fragmentation for complex geometries. All discontinuity relations at the material interface, including viscosity, surface tension, phase change and chemical reaction, are derived. Furthermore, the mathematical model of interface conditions for multiphase flows with complex physical and thermodynamic characteristics is established. This work improves the ability to accurately simulate complicated flow phenomena. It is also conducive to solve the practical problems with phase change accurately and efficiently, which are generally induced by the interaction of shock waves, chemically reacting flows and droplets. Based on these techniques, this project will extend the ghost fluid method to simulate three-dimensional compressible reacting multiphase flows with complex behaviors. A detailed simulation platform CA-HIFI for interface evolution in large scale scientific computation will be developed. Effectiveness of the numerical method is validated and typical applications are also performed. The ghost fluid method used in this project can provide technical support for some challenging problems such as the enhancement of fuel-air mixing in supersonic flow field. The engineering application of this method has not been found at present.