Abstract: The effect of ambient condition on the atomization characteristics were numerically simulated by using centrifugal nozzle as the research object, the influence of ambient air pressure and temperature on atomization characteristics parameters such as oil film thickness and atomization angle were obtained.With the FLUENT used,when the injection pressure was 4.0 MPa, the fuel temperature is 100 ℃,the ambient temperature from －50 ℃ to 400 ℃and the ambient pressure in the range of 0.1～3.0 MPa were numerically simulated.The results show that when the ambient pressure is constant, the temperature increases, the air density decreases, the fuel evaporation intensifies, the gas phase fuel ratio increases, and the atomization effect increases. When the ambient temperature is constant, the environmental pressure increases, the air density increases, the crushing occurs earlier, the oil film thickness increases, and the liquid phase fuel ratio increases, although the spray cone angle and the interaction between oil and gas increase, but it is not conducive to fuel atomization.

Key words: Centrifugal nozzle, Atomization characteristics, Ambient pressure, Ambient temperature, Numerical simulation

摘要： 以离心式压力雾化喷嘴为研究对象，对不同环境条件下喷嘴雾化特性的影响进行了数值模拟研究，获得了不同环境压力和环境温度对油膜厚度和雾化锥角等雾化特性参数的影响规律。利用FLUENT软件，在喷油压力4.0 MPa、燃油温度100 ℃的条件下，对环境压力由0.1 MPa升至3.0 MPa、环境温度由-50 ℃升至400 ℃过程中的燃油雾化特性进行了数值计算。结果表明，当环境压力一定时，环境温度增加，气体密度减小，燃油蒸发作用加剧，气相燃油比例增大，雾化效果增强；当环境温度一定时，环境压力增加，气体密度增大，油膜厚度增大，液相燃油比例增大，不利于燃油雾化。

关键词: 离心式喷嘴, 雾化特性, 环境压力, 环境温度, 数值计算