环形燃烧室内气液同轴雾化数值模拟研究

Numerical Simulation of Gas Liquid Coaxial Atomization in Annular Combustor

关键词:  同轴气流  环形燃烧室  OpenFOAM  射流  雾化

Key words:  Coaxial gas flow  Annular combustion chamber  OpenFOAM  Jet  Atomization

摘要:

为了探究连续旋转爆轰发动机环形燃烧室内煤油射流在同轴气流作用下的雾化过程，采用开源软件OpenFOAM中基于欧拉-拉格朗日方法的SprayFoam求解器对其进行数值模拟，开展了喷射角度、相邻喷嘴夹角、背压和气液速度比对雾化特性影响的研究。研究表明：SprayFoam求解器可以较好地模拟环形燃烧室内液态燃料的喷射雾化特性；随着喷射角度和背压增大，液滴雾化后的粒径逐渐减小；相邻喷嘴角度为15°时燃料雾化后的液滴分布最佳，此时液滴索特尔平均直径为85.1μm；不同气液速度比的射流末端液滴速度最终趋于一致，均约为160m/s。

Abstract:

To investigate the atomization process of kerosene jet in the annular combustor of continuous rotating detonation engine under the action of coaxial gas flow， the SprayFoam solver based on Eulerian-Lagrangian method in open source software OpenFOAM was used to simulate the process. The effects of spray angle， angle between adjacent nozzles， back pressure and gas-liquid velocity ratio on atomization characteristics were analyzed. The results show that the SprayFoam solver used in the study can effectively simulate the spray atomization characteristics of liquid fuel in annular combustor. With the increase of injection angle and back pressure， the droplet size decreases gradually after atomization. The best droplet distribution after fuel atomization is obtained when the angle between the adjacent nozzle is 15°， where the Sauter mean diameter of droplets is 85.1μm. The droplet velocity at the end of the jet with different gas-liquid velocity ratios finally tends to be the same， which is about 160m/s.