可调向心涡轮蜗壳流动周向非均匀性的研究  

Uniformity of Circumferential Flow in Volute of Variable Radial Turbine

作　　者：邢世凯[1] 李聚霞[2] 李晴[1] 陈立辉[1] 马朝臣[3] 

机构地区：[1]河北师范大学职业技术学院,河北石家庄050024 [2]石家庄信息工程职业学院,河北石家庄050035 [3]北京理工大学机械与车辆学院,北京100081

出　　处：《内燃机学报》2016年第6期562-568,共7页Transactions of Csice

基　　金：河北省科技支撑计划资助项目(15273703D);河北省高等学校自然科学研究青年基金资助项目(QN20131017;QN2014164);河北师范大学博士基金资助项目(L2016B15)

摘　　要：针对某可调向心涡轮增压器,基于蜗壳流动周向非均匀性的分布规律,提出采用改进喷嘴座连接臂结构和非均匀布置可调导叶的设计方案,以降低涡轮级各部分的流动损失,提高涡轮效率.结果表明:改型后涡轮工作在发动机标定功率工况对应相似转速条件下效率相对提高值最大为5.18%,,发动机最大转矩工况对应相似转速条件下效率相对提高值最大为3.57%,;改型后蜗壳出口气流角变得更加均匀,蜗壳出口气流角与导叶开度角相接近,减小了喷嘴环区域的流动损失,解释了改型前、后涡轮效率提高的原因;改型后各叶轮流道流量的周向非均匀性明显降低,各叶轮叶片负荷周向分布更加均匀.证明改型方案对提高涡轮效率,降低叶片振动,延长涡轮有效使用寿命具有积极的影响.For a variable radial turbocharger, according to the circumferential non-uniform flow distribution in volute, a design for improving the nozzle seat connecting arm＇s structure and non-uniform arrangement of variable vanes was proposed to decrease the turbine stage flow losses and improve turbine efficiency. Results show that turbine efficiency improves by 5.18% under the reduced speed condition corresponding to the engine rated power working condition, and the efficiency increases by 3.57% at the reduced speed condition corresponding to the maximum torque working conditions. The flow angle at volute outlet of the optimized turbine becomes more uniform. Flow angle is close to the opening angle of guide vane, which decreases the flow loss in the nozzle ring and explains the reason for the improved turbine efficiency. After optimization, the flow non-uniformity among impeller channels is signifi- cantly reduced, and the distribution of the blade load is more uniform. The study proves that the retrofit scheme is helpful to increase turbine efficiency, reduce blade vibration and extend the workin life of turbine.

关 键 词：可调向心涡轮 周向非均匀性 非均布导叶 内部流场 数值计算 

分 类 号：TK421.8[动力工程及工程热物理—动力机械及工程]