车用涡轮增压器径流涡轮的背盘冷却技术研究  

Back-Disc Cooling Technology of Radial Turbine for Vehicle Turbocharger

作　　者：马超 李延昭 张健健 朱光前 MA Chao;LI Yanzhao;ZHANG Jianjian;ZHU Guangqian(School of Mechanical-electronic and Vehicle Engineering,Weifang University,Weifang 261061,China;Key Laboratory of Internal Combustion Engine Turbocharging System,China Machinery Industry Federation,Shouguang 262718,China;Kangyue Technology Co.,Ltd,Shouguang 262718,China)

机构地区：[1]潍坊学院机电与车辆工程学院,山东潍坊261061 [2]机械工业内燃机增压系统重点实验室,山东寿光262718 [3]康跃科技股份有限公司,山东寿光262718

出　　处：《车用发动机》2020年第5期28-35,共8页Vehicle Engine

摘　　要：随着车用柴油机排放法规和功率密度的不断提升,增压器转速及涡前温度不断提高,涡轮轮背发生热-机械疲劳失效的风险大幅增加。为了提高涡轮背盘可靠性,提出了一种径流涡轮背盘冷却技术,利用流固耦合的数值仿真方法研究了从中冷器后引入冷却空气,对背盘热应力的改善以及对涡轮机整机性能的影响。结果表明:当消耗1.0%,2.0%和3.0%的相对冷却流量时,背盘热应力分别比无冷却时降低31 MPa,108 MPa和132 MPa,综合应力分别降低3.8%,13.1%和16.0%。背盘冷却对涡轮机性能的影响较小,当相对冷却流量消耗3.0%以内时,冷却对膨胀比的影响可以忽略,热效率的降低不超过1.0%。With the continuous upgrading of vehicle diesel engine emission regulation and power density,the turbocharger rotating speed and turbine inlet temperature also increase continuously and hence the risk of thermal-mechanical fatigue failure of the turbine wheel back-disc increases significantly.In order to improve the reliability of turbine back-disc,a back-disc cooling technology for radial turbine was proposed.The influences of the relative mass flow rate of cooling air introduced from the pipe after an intercooler on the thermal stress of turbine back-disc and the performance of turbine were studied by the fluid-solid coupling numerical simulation.The results show that the thermal stress of back-disc decrease by 31 MPa,108 MPa and 132 MPa respectively and the synthetic stresses reduce by 3.8%,13.1%and 16.0%respectively when 1.0%,2.0%and 3.0%relative cooling flow is consumed.The effect of back-disc cooling on turbine performance becomes weak.Besides,the effect of cooling on expansion ratio can be ignored and its thermal efficiency reduction is no more than 1.0%at the relative cooling flow of less than 3.0%.

关 键 词：柴油机 涡轮增压器 径流涡轮 背盘冷却 热应力 

分 类 号：TK422[动力工程及工程热物理—动力机械及工程]