振荡环境下多层三明治模型火焰波动特性研究

Study on flame fluctuation characteristics of multi-layer sandwichmodel in oscillating environment

基于OpenFOAM计算平台,针对发动机振荡环境下AP/HTPB复合推进剂微观火焰的燃烧波动特性开展了数值计算研究。由于传统的三明治模型并未考虑相邻火焰之间的影响,因此本文采用多层三明治构型,在平均压强5.7 MPa、振荡频率323 Hz、压强振荡幅值为0.2 MPa、质量比α_(AP/HTPB)=7/3的情况下,开展数值模拟和分析工作。结果表明,基于OpenFOAM的建立的数值模拟方法,可获得发动机振荡环境下AP/HTPB三明治模型火焰的波动特性,包括火焰高度、火焰摆动角度、对近燃面气相区域的热反馈等参数的变化。对比分析表明,相邻火焰会对彼此的火焰波动特性产生影响,多层三明治模型对推进剂细观火焰的描述更加合理。

Based on the calculation platform of OpenFOAM,the numerical simulation of the combustion fluctuation of AP/HTPB composite propellants＇ micro-flame in engine oscillation environment is carried out.Because the traditional sandwich model does not consider the influence of adjacent flames,the multi-layer sandwich configuration is adopted in this paper.In the case of pressure of 5.7 MPa,oscillation frequency of 323 Hz,amplitude of pressure oscillation 0.2 MPa,mass ratio α_（AP/HTPB）= 7/3,the numerical simulation and analysis are carried out.The results show that the fluctuation characteristics of the AP/HTPB sandwich model flame can be obtained based on the numerical simulation method established by OpenFOAM,including the flame height,the flame swing angle and the thermal feedback of the propellant surface.Comparative analysis shows that the adjacent flames will have an impact on the flame fluctuation characteristics,and multi-layer sandwich model is more reasonable for the description of propellant microscopic flame.