车用涡轮增压器涡轮级流场特性的仿真研究

Simulation Study on Flow Field Characteristics of Turbine Stage of Vehicle Turbocharger

基于计算流体动力学两相流技术对某车用涡轮增压器涡轮级的流场特性进行了仿真研究,分析不同涡轮转速下涡轮级的废气颗粒质量浓度、废气流速、压力及温度变化规律。研究结果表明,当涡轮转速由100000 r/min加快至140000 r/min时,涡轮级废气颗粒质量分数呈现出降低趋势,废气颗粒分布的均匀性提高。涡轮级废气的最大流速由211.121 m/s加快至306.624 m/s,效率提高27%。随着涡轮转速的加快,涡轮级最大压力由159771.84 Pa增大至253244.031 Pa,温度梯度不断增大,温度分布的均匀性则有所降低。

Based on the computational fluid dynamics two-phase flow technology,a simulation study on the flow field characteristics of turbine stage of a vehicle turbocharger was conducted,and the fluctuation regular pattern of exhaust gas particle mass concentration,exhaust gas flow rate,pressure and temperature of the turbine stage at different turbine speeds were analyzed.The findings show that when the turbine speed is increased from 100000 r/min to 140000 r/min,the mass fraction of exhaust gas particles in the turbine stage shows a decreasing trend,and the uniformity of the exhaust gas particle distribution is improved.When the maximum flow rate of exhaust gas at turbine stage has been accelerated from 211.121 m/s to 306.624 m/s,the efficiency has increased by 27%.As the turbine speed increases,the maximum pressure of the turbine stage increases from 159771.84 Pa to 253244.031 Pa,the temperature gradient increases without intermission,and the uniformity of temperature distribution decreases.