某柴油机增压器支架NVH性能分析与改进  

Analysis of NVH performance of a diesel turbocharger bracket and its improvement

作　　者：李俊琦 高书贞 姚亚俊 张晨 梁伟 LI Junqi;GAO Shuzhen;YAO Yajun;ZHANG Chen;LIANG Wei(Weichai Power Co.,Ltd.,Weifang 261061,China)

机构地区：[1]潍柴动力股份有限公司,山东潍坊261061

出　　处：《内燃机与动力装置》2023年第6期90-96,共7页Internal Combustion Engine & Powerplant

基　　金：国家重点研发计划项目(2022YFE0100010)。

摘　　要：为解决某轻型紧耦合后处理柴油机在台架开发阶段出现的排气系统增压器支架断裂故障,利用有限元仿真分析方法,建立柴油机排气系统三维模型,利用SimLab和HyperMesh软件联合划分四面体单元网格,导入ABAQUS软件计算得到系统模态结果,结合噪声、振动与声振粗糙度(noise vibration harshness,NVH)测试试验及故障件材料微观分析,查找增压器支架断裂的原因;提出台架试验条件及增压器支架结构改进方案,并进行NVH性能测试及耐久试验验证。结果表明:柴油机与台架存在共振、增压器支架设计刚度及材料强度不足是增压器支架断裂的原因;使用垂直刚度更低的软垫作为该柴油机台架的支撑软垫,共振转速由776 r/min降低为318 r/min,振动速度由382 mm/s降低为89 mm/s,避免柴油机与台架共振的风险;更换支架材料并在支架受力变形方向增加条形筋,使排气系统NVH性能满足要求,解决了增压器支架断裂故障。In order to solve the fracture of the turbocharger bracket of a lightweight tight-coupled post-treatment diesel engine during the performance development,a three-dimensional model of the exhaust system of the diesel engine is established by using the finite element simulation analysis method,and the tetrahedral unit mesh is jointly divided by SimLab and HyperMesh software.The modal results of the system are calculated by ABAQUS finite element analysis software.Combined with the noise vibration harshness(NVH)test and the microscopic analysis of the fault parts,the cause of the fracture is summarized.The test for the improvement scheme of turbocharger support structure are put forward,and NVH performance test and durability test are carried out.The results show that the reasons for the fracture of the turbocharger bracket are the resonance between the engine and the bench,the design stiffness of the turbocharger bracket and the insufficient material strength.Using the cushion with lower vertical stiffness as the turbocharger bracket cushion developed for the platform of this model,the resonance speed can be reduced from 776 r/min to 318 r/min,and the vibration speed can be reduced from 382 mm/s to 89 mm/s,which avoids the resonance risk between the whole machine and the platform.The turbocharger bracket material is replaced,and additional bars in the direction of the bracket stress deformation are added,which can increased the tensile strength of turbocharger bracket,the NVH performance of the exhaust system can meet the requirements,and the fault of the turbocharger bracket fracture is solved.

关 键 词：紧耦合后处理柴油机 增压器支架 NVH 断裂 共振 

分 类 号：TK427.13[动力工程及工程热物理—动力机械及工程]