高焓流动中的可压缩颗粒求解器(第1部分):考虑多物理效应的点力颗粒两相流理论方程

Particle solver in compressible high enthalpy flow (Part 1): the theoretical equations of point particle laden flow

从含烧蚀颗粒的高超声速边界层到航空发动机燃烧室或火箭发动机燃烧室里的气液、气固两相燃烧等问题,都存在弥散相颗粒调制携带流体的两相耦合物理过程。尽管不可压颗粒两相流的理论、数值工具和实验都比较成熟,但可压缩颗粒两相流与不可压缩的情况是截然不同的。本文首先对可压缩颗粒两相流动力学和热力学进行理论研究,理论分析了经典的可压缩流体动力学和热力学方程,把颗粒动力学对不可压流动的调制理论修正拓展到了可压缩情况,发现了可压缩颗粒两相流特有的动量和能量调制无量纲参数;推导了考虑多物理效应的颗粒动力学方程,并将其与携带流体相的控制方程耦合。研究发现,尽管多物理效应下的颗粒动力学是复杂的,但其影响携带流体相的路径是唯一确定的,即:多物理效应的颗粒动力学仅能通过相间阻力调制携带流体相的动量,通过相间阻力做功和热对流调制携带流体相的能量。

Modulation of dispersed particles on the carrying fluid is a common phenomenon in aeronautic and aerospace engineering,including the ablation particle-laden boundary layer,the particles of solid fuel combustion in the rocket engine and the droplets of liquid fuel.Although theoretical,numerical and experimental studies on the particle laden incompressible flow have been well established,the particle laden compressible flow is distinctly different.In view of this,it is necessary to conduct a theoretical study on the dynamics and thermodynamics of particle laden compressible flow.We established the theoretical equations,and discovered the unique particle modulation parameters which are different from those of the incompressible counterpart.By considering the extreme mechanical environmental condition,the particle dynamic and thermodynamic equations have been derived and coupled to the governing equations of the carrying phase. It is found that, even with complicate multi-physics effects, the pathway of particle modulation on the compressible flow is deterministic, i.e., the carrying fluid momentum is modulated by the drag force of particles, while the energy is exchanged due to the work done by the drag force as well as the thermal convection. The present study lays a theoretical foundation for developing the particle solver for compressible flow.