模型参数对直喷汽油发动机喷雾特性的影响

Effects of Model Parameters on Spray Characteristics of Gasoline Direct-Injection Engines

摘要:

基于单向耦合模拟方法，研究了湍流模型参数、单向耦合模型参数和破碎模型参数对喷雾贯穿距和粒径的影响。结果表明，湍流模型参数C_ε1和RT（Rayleigh-Taylor）破碎模型尺寸参数C_RT对喷雾贯穿距的影响最大，KH（Kelvin-Helhmoltz）破碎模型尺寸参数C_KH和C_RT对粒径的影响最大。在此基础上建立了适用于不同工况的高精度喷雾模型，标准Spray G工况下，模拟结果与实验结果误差在3%以内；不同环境气体密度下，多种工况的模拟结果与实验结果误差在10%左右。

Abstract:

This paper investigates the effects of turbulence model parameter， one-way coupling model parameter， and break-up model parameters on spray penetration and droplet size based on the VOF-spray one-way coupling model. The results indicate that the RANS constant C_ε1 and the RT model size constant C_RT have the greatest effect on the spray penetration， and size constants C_KH and C_RT have the greatest effect on the droplet size. Based on the above analysis， it establishes a high precision spray model for different working conditions. The error between experiment and simulation is within 3% for standard Spray G condition， and around 10% error for different ambient gas densities.