涡轮增压器涡轮BPF噪声试验研究

李伟1，2，李国祥1，马超2，刘莹2，张健健2，付丽娇2，苗熠芝2，张晓林2,3

1. 山东大学能源与动力工程学院，山东济南250061；2. 康跃科技股份有限公司，山东寿光262718；3. 机械工业内燃机增压系统重点实验室，山东寿光262718

摘要：为改善涡轮叶片通过频率（blade passing frequency,BPF）噪声，研究噪声产生机理，仿真分析流道喉舌与涡轮进口距离对涡轮进口静压分布的影响，通过试验研究流道喉舌与涡轮进口距离和涡轮叶片数对噪声的影响，提出增大流道喉舌与涡轮进口距离、增加涡轮叶片等改善涡轮BPF噪声方案。结果表明：由于流道喉舌结构，涡轮进口静压存在明显不均匀性，是涡轮BPF噪声产生的主要原因；增加涡轮叶片、增大流道喉舌与涡轮进口距离是改善涡轮BPF噪声的有效途径。

关键词：涡轮增压器；涡轮BPF噪声；流道喉舌；涡轮叶片数量；涡轮进口静压

Experimental research on turbine BPF noise of turbocharger

LI Wei1，2, LI Guoxiang1, MA Chao2, LIU Ying2, ZHANG Jianjian2, FU Lijiao2, MIAO Yizhi2, ZHANG Xiaolin2,3

1. School of Energy and Power Engineering, Shandong University, Jinan 250061, China; 2. Kangyue Technology Co., Ltd., Shouguang 262718, China;3. Key Laboratory of Internal Combustion Engine Pressurization System in Machinery Industry, Shouguang 262718, China

Abstract:In order to improve the turbine BPF noise, the mechanism of noise generation is discussed.Theinfluence of the distance between the volute throat and the turbine inlet on the static pressure distribution of the turbine inlet are simulated and analyzed, and the influence of the distance between the volute throat and the turbine inlet and the number of turbine blades on the noise are experimentally studied,and a scheme to improve BPF noise by increasing the distance between mouthpiece and turbine inlet and increasing turbine blades are proposed.The test results show that the turbine inlet static pressure shows obvious nonuniformity due to the volute throat structure,which is an important source for turbine BPF noise.Increasing the number of turbine blades and the distance between the volute throat and the turbine inlet are the effective way to improve BPF noise.

Keywords:turbocharger；turbine BPF noise；volute throat；number of turbine blades；static pressure at turbine inlet

基于Inspire软件的复合支架轻量化拓扑优化设计

刘洋1,2, 申加伟1,2, 王超1,2, 田少聪1,2, 徐贤发1,2

1.内燃机可靠性国家重点实验室，山东潍坊261061；2. 潍柴动力股份有限公司 发动机研究院，山东潍坊261061

摘要：对发动机附件的复合支架结构进行轻量化拓扑优化设计，选择和校核支架材料，采用Creo建立Inspire仿真模型，根据优化结果中加强筋起筋趋势和局部镂空情况对模型进行重构，在兼顾铸造工艺的基础上对支架结构进行整合设计，使复合支架质量减少约60%，结构模态和强度均比初始设计提高。拓扑优化的复合支架满足工程设计要求，避免过度设计，充分发挥了材料的性能，实现了轻量化的设计目标。

关键词：支架；变密度；拓扑优化；轻量化

Lightweight design on composite bracket based on topology optimization by Inspire

LIU Yang1,2, SHEN Jiawei1,2, WANG Chao1,2, TIAN Shaocong1,2, XU Xianfa1,2

1.State Key Laboratory of Engine Reliability, Weifang 261061, China; 2.R&D Center, Weichai Power Co., Ltd., Weifang 261061, China

Abstract:The lightweight topology optimization design of engine composite bracket is carried out by Creo Inspire simulation model. According to the result of optimization in the tendency of reinforcing rib and partial hollowing out, the structure of composite bracket is reconstructed on the basis of considering the casting technology, the weight of final design reduced by 60%, the modal and strength of the structure are improved compared with the original design. Topological optimization could meet the requirements of engineering design, avoid excessive design, improving material utilization and avoid excessive design at the same time. The design goal of light weight is achieved.

Keywords: bracket; variable density; topology optimization; lightweight

基于有限元仿真的发动机吊耳强度分析

王俊然1,2，程市1,2，曾超1,2，刘伦伦1,2，沈琳清1,2，谢永胜1,2

1.内燃机可靠性国家重点实验室，山东潍坊261061；2.潍柴动力股份有限公司，山东潍坊261061

摘要：为保证发动机吊装的安全性，建立发动机吊耳结构有限元模型，针对发动机垂直起吊和斜拉起吊2种工况，提出不同的吊耳受力分解方法，并进行有限元仿真分析，结果表明垂直起吊工况吊耳所受最大应力小于斜拉起吊工况。对比斜拉工况下发动机吊耳所受应力的仿真值与测试值，相对误差为8%左右，在可接受范围内，证实发动机吊耳有限元仿真方法的有效性。

关键词：发动机吊耳；斜拉工况；垂直工况；有限元分析

Simulation of engine lug strength based on finite element analysis

WANG Junran1,2， CHENG Shi1,2， ZENG Chao1,2， LIU Lunlun1,2，SHEN Linqing1,2， XIE Yongsheng1,2

1.State Key Laboratory of Engine Reliability，Weifang 261061，China；2.Weichai Power Co.，Ltd.，Weifang 261061，China

Abstract:Taking the lifting lug of an engine as the research object, the finite element model of the structure of the engine lifting lug is established, and the two working conditions of the engine: vertical lifting and slope lifting are considered. Different stress decomposition methods of the lifting lug are put forward, and the finite element simulation analysis is carried out. It is concluded that the vertical lifting condition is better than the oblique pulling lifting condition. The relative error is about 8% by comparing the simulation and the test of the stress on the engine lug under the cablestayed condition, which proves the effectiveness of the finite element simulation method for the engine lifting lug.

Keywords:engine lug; slope lifting; vertical lifting; finite element analysis

发动机结构及参数对缸孔变形的影响

蔡强1,2，胡琦山1,2，李连升1,2，赵文彬1,2，任燕平1,2

1.内燃机可靠性国家重点实验室，山东潍坊261061；2.潍柴动力股份有限公司发动机研究院，山东潍坊261061

摘要：以某无缸套柴油机为研究对象，建立机体-缸垫-缸盖一体化有限元计算模型，采用傅里叶变换研究发动机各结构参数对缸孔变形的影响。研究结果表明：减少机体上水孔和清砂孔数量，可以有效降低缸孔变形；机体设计时应控制上水孔和清砂孔的截面积尽可能小，且要尽量远离缸孔；螺栓的布置对缸孔变形有一定的影响，而且4颗螺栓对4阶缸孔变形最为敏感，设计时应使螺栓的跨距尽量均匀；在缸垫密封满足要求的情况下，可以通过降低最外侧2个缸的螺栓轴力来减小2阶缸孔变形；增大缸心距可以改善机体刚度分布，有效降低缸孔变形。

关键词：缸孔变形；傅里叶级数；无缸套机体；热机耦合计算

Influence of engine structure and parameters on bore distortion

CAI Qiang1,2, HU Qishan1,2, LI Liansheng1,2, ZHAO Wenbin1,2, REN Yanping1,2

1.State Key Laboratory of Engine Reliability, Weifang 261061, China;2.R&D Center, Weichai Power Co., Ltd., Weifang 261061, China

Abstract:The cylinder block of a jacketfree diesel engine is studied, the thermomechanical coupling finite element model is established, and the influence of structural parameters to the bore distortion are studied by using Fourier series. It is found that reducing the number of upper water hole and sand hole can effectively reduce the bore distortion.The smaller sectional area of the hole and away from the hole, the less bore distortion. The arrangement of bolts has a certain influence on the bore distortion, especially the four bolts are the most sensitive to the fourthorder bore distortion. So the span of bolts should be considered as uniform as possible in the design.When the gasket seal meets the requirements, the bore distortion of the second order can be reduced by decreasing the bolt force on both sides of the cylinder.Improving the stiffness distribution by increasing the cylinder center distance can effectively reduce the bore distortion.

Keywords:bore distortion; Fourier series; block without liner；thermomechanical coupling method

一种双阀结构共轨喷油器性能仿真

顾娇娇, 况涪洪, 吴小军, 奚星, 徐春龙, 李春晖

中国北方发动机研究所，天津300400

摘要：提出并设计一种双阀结构的新型电控喷油器，详细介绍结构设计原理，建立典型结构喷油器与新型双阀结构喷油器的一维仿真模型，进行模型校验，仿真研究双阀结构喷油器的结构参数对性能的影响，提出优化设计的建议。研究结果表明，新型双阀结构共轨喷油器比典型球阀结构共轨喷油器的针阀提升和关闭速度更快，可大幅降低喷油嘴座面节流的影响，提高喷油嘴喷油压力，缩短喷油持续期。

关键词：共轨喷油器；双阀；针阀速度；喷油特性；仿真

Simulation on performance of the common rail injector with doublevalve structure

GU Jiaojiao, KUANG Fuhong, WU Xiaojun, XI Xing, XU Chunlong, LI Chunhui

China North Engine Research Institute (Tianjin), Tianjin 300400, China

Abstract:In this paper, a new type of electronic fuel injector with double valve structure is designed and proposed. The principle of structural design is introduced in detail. The onedimensional simulation model for typical structural injector and doublevalve structural injector is established and verified. The influence of structural parameters on the performance of doublevalve structural injector is studied by simulation, and suggestions for further optimization design are put forward. The results show that the newtype doublevalve common rail injector has a faster lifting and closing speed than the typical structure injector. The doublevalve injector can greatly reduce the throttling effect of the seat surface of the fuel injector, so as to increase the actual injection pressure of the fuel injection nozzle and shorten the fuel injection duration.

Keywords:common rail injector; double valve; needle valve speed; injection characteristics; simulation

装载机用柴油机整车路谱的台架试验研究

范振勇1,2，王素梅1,2，何乃鹏1,2，万永召1,2，赵联海1,2

1.内燃机可靠性国家重点实验室，山东潍坊261061;2.潍柴动力股份有限公司，山东潍坊261061

摘要：基于装载机用柴油机经济性和动力性的典型瞬态路谱，提出台架模拟整车路谱的试验方法，研究台架实现瞬态试验的可行性,引入线性回归作为台架试验有效性的评价依据。台架模拟试验结果表明:装载机经济性路谱采用转速/扭矩模式时，通过比例积分微分调节控制参数后，实际值与设定值跟随性较好，线性回归结果满足要求；装载机动力性路谱采用扭矩/油门模式，转速跟随性较好。对2台不同配置柴油机进行台架和整车对比试验，台架模拟与整车试验结果很好吻合，表明基于台架模拟整车路谱的试验方法可行，可以用于柴油机台架性能的优化研究。

关键词：台架模拟；装载机；路谱；试验方法；线性回归

Experimental study on road spectrum of wheel loader withengine test bench

FAN Zhenyong1,2， WANG Sumei1,2， HE Naipeng1,2，WAN Yongzhao1,2， ZHAO Lianhai1,2

1.State Key Laboratory of Engine Reliability, Weifang 261061, China; 2.Weichai Power Co.,Ltd.,Weifang 261061, China

Abstract:Based on the typical transient road spectrum of fuel economy and power performance of loader diesel engine, the test method of bench simulation road spectrum is proposed, and the feasibility of bench test to realize transient test is studied. The linear regression is introduced as the evaluation basis of bench test effectiveness. The results of the bench simulation test show that the speed / torque mode is adopted for the economic road spectrum of the loader, and the actual value and the set value are adjusted by the proportional integral differential control, and the linear regression results meet the requirements; the torque / throttle mode is adopted for the power spectrum of the loader, and the speed tracking performance is good. The bench simulation and vehicle test results of two diesel engines with different configurations are compared and verified. The results show that the test method based on bench simulation of vehicle road spectrum is feasible and can be used to guide the performance optimization of diesel engine on the bench.

Keywords:bench test; wheel loader; spectrum; test method; linear regression

柴油机气门座圈异常磨损分析及改进

叶飞1，吕祥2，李杰1

1.潍柴动力扬州柴油机有限责任公司技术中心，江苏扬州225009；2.潍柴动力股份有限公司发动机技术研究院，山东潍坊261061

摘要：为解决某排放升级后重型车用柴油机在耐久试验过程中出现的气门座圈异常磨损故障，分析气门座圈磨损机理、负荷、接触条件、形貌和金相组织，确定爆发压力增加和润滑条件差是导致气门座圈异常磨损故障的原因。通过调整气门座圈与气门的密封锥面角度、增加气门与座圈密封带面积，从而减小接触比压，提高与摩擦副的配合。改进后的耐久试验结果表明：气门座圈的磨损大幅降低，有效解决了排放升级后气门与气门座圈的磨损问题。

关键词：气门座圈；异常磨损；设计改进

Analysis of the valve seat′s wear of diesel engine and it′s improvement

YE Fei1, L Xiang2, LI Jie1

1.R&D Center, Weichai Power Yangzhou Diesel Engine Co., Ltd.,Yangzhou 225009, China；2.R&D Center，Weichai Power Co., Ltd., Weifang 261061，China

Abstract:In order to solve the wear problem of heavy duty diesel valve seat, the wear mechanism，the loading environment and contact condition, the surface appearance of the seat wear are analyzed.The increased peak pressure and the poor lubrication are the main factors for the wear. An improved valve seat is designed with reducing the angel of the seal, increasing the contact area of the valve and the seat for decreasing the contact pressure and optimizing the rubbingpair.The endurance test results show that the wear of valve seat is greatly reduced, the valve seat wear failure is resolved by optimization of the valve seat angle and increasing of sealing area.

Keywords:valve seat;wear; design improvement

醇氢燃料在甲醇发动机上的试验研究

张江华1, 檀昌雅2

1.南昌工学院新能源车辆学院，江西南昌330108；2.淮北师范大学信息学院，安徽淮北235000

摘要：利用甲醇发动机高温尾气加热裂解装置，将甲醇裂解成甲醇裂解气（氢气、一氧化碳、甲醇蒸气），并与甲醇进行混合形成醇氢燃料（甲醇裂解气、甲醇），结合发动机复合喷射技术实现甲醇裂解气与甲醇的掺烧。对比和试验研究甲醇发动机燃用醇氢燃料、甲醇、汽油3种不同燃料的外特性、油耗率、排气温度及污染物排放，结果表明：发动机燃用醇氢燃料时，动力性与甲醇燃料相当，但优于汽油，发动机燃用醇氢燃料时，发动机的扭矩比甲醇、汽油燃料分别提高了05%、56%；燃油消耗率是甲醇的07~08倍，是汽油的150~174倍；发动机的排气温度与甲醇、汽油相比分别降低了3%、14%；CO、总碳氢化合物和NOx排放与甲醇相比分别降低了53%、46%和68%，与汽油相比分别降低了77%、68%和72%。

关键词：醇氢燃料；外特性；油耗；温度；排放

Experimental study on methanol hydrogen fuel used in methanol engine

ZHANG Jianghua1, TAN Changya2

1.New Energy Vehicle College, Nanchang Technology and Science of University, Nanchang 330108, China；2.School of Information, Huaibei Normal Univesity, Huaibei 235000, China

Abstract:Methanol is cracked into methanol cracking gas (hydrogen+carbon monoxide+methanol steam) ,methanol cracking gas mixed with methanol to form methanol hydrogen fuel (methanol cracking gas+methanol) in the high temperature tail gas heating and cracking device of methanol engine. Combined with the technology of composite jet engine, the mixed combustion of methanol cracked gas and methanol is realized. In this paper, the external characteristics, fuel consumption rate, exhaust temperature and pollutant emission characteristics of three different fuelsalcohol hydrogen fuel, methanol and gasoline are contrasted and researched by the experiments. The results show that the power performance of methanol hydrogen fuel is better than that of gasoline and is equivalent to that of methanol; Compared with methanol and gasoline, the engine torque of methanol hydrogen fuel is increased by 0.5% and 5.6% respectively, the fuel consumption rate of methanol hydrogen fuel engine is 0.7-0.8 times of that of methanol and 1.5-1.74 times of that of gasoline; the exhaust temperature of methanol hydrogen fuel engine is decreased by 3% and 14% respectively. Carbon monoxide (CO), total hydrocarbon (THC) and nitrogen oxides (NOx) of methanol hydrogen fuel are reduced by 53%, 46%, 68% compared with methanol, and 77%, 68%, 72% compared with gasoline fuel.

Keywords:methanol hydrogen fuel; external characteristics; fuel consumption; temperature; emission

热冲击工况中冷却模块密封方式优化设计

成敬敏1,2,李建文1,2,王洪忠1,2,王磊1,2,王慧辉1,2,李寒寒1,2

1.内燃机可靠性国家重点实验室,山东潍坊261061;2.潍柴动力股份有限公司，山东潍坊261061

摘要：针对发动机热冲击运行工况中冷却模块密封面存在的漏水风险，建立机体、冷却模块、螺栓、垫片的有限元模型，对冷却模块在热冲击工况中的密封性能进行仿真分析，研究螺栓数量及垫片材料对密封性能的影响。结果表明，增加螺栓数量时密封效果改进不明显，采用回弹性（补偿量）更大的不锈钢SUS301新垫片密封效果较好。经热冲击工况耐久试验考核，采用新垫片密封的发动机未出现漏水故障，为后续密封方式设计提供参考。

关键词：冷却模块；热冲击工况；补偿量；有限元分析

Optimizing design of sealing methods of cooling module at thermal shock condition

CHENG Jingmin1,2， LI Jianwen1,2， WANG Hongzhong1,2， Wang Lei1,2， WANG Huihui1,2， LI Hanhan1,2

1.State Key Laboratory of Engine Reliability，Weifang 261061，China；2.Weichai Power Co.,Ltd., Weifang 261061，China

Abstract: Aiming at the risk of water leakage on the sealing surface of cooling module under the condition of engine thermal shock, the finite element model of engine block, cooling module, bolt and gasket are established. The sealing performance of cooling module under thermal shock condition is analyzed by simulation tool, and the influence of bolt quantity and gasket material on sealing performance is studied. The results show that the sealing effect of the method of increasing the number of bolts is not obvious, and the new gasket made of stainless steel SUS301 with greater resilience (compensation) has better sealing effect. After the thermal shock durability test, the engine with new gasket seal has no water leakage fault, which provides a reference for the subsequent seal design.

Keywords:cooling module；thermal shock condition；gasket；finite element analysis

重型拖拉机控制器的引导加载程序与上位机设计

谭文阳，李军伟*，朱青松

山东理工大学交通与车辆工程学院，山东淄博255049

摘要：针对重型拖拉机控制器的升级维护问题，采用32位微控制器MPC5744P，开发基于控制器局域网络总线技术的引导加载程序，设计上位机。依据引导加载程序的需求开发FlexCAN模块、Flash模块的底层驱动程序及S19文件的解析代码。为了实现对程序的在线更新，利用Python的外部工具PyQt5设计相应的上位机。为验证系统性能，通过上位机对MPC5744P开发板进行程序升级，对引导加载程序进行测试。测试结果表明：设计的引导加载程序能够通过与上位机的交互准确实现应用程序的在线升级，符合设计要求。

关键词：引导加载程序；重型拖拉机控制器；Flash驱动；FlexCAN通信；上位机设计

Design of bootloader and upper computer of heavy tractor controller

TAN Wenyang， LI Junwei*， ZHU Qingsong

School of Traffic and Vehicle Engineering, Shandong University of Technology,Zibo 255049,China

Abstract:In order to facilitate the upgrade and maintenance of automobile controller, MPC5744P CAN bus based bootloader and PyQt5 based upper computer are designed and developed.The program update of microcontroller MPC5744P is completed through the configuration of FlexCAN communication module, the design ofFlash driver, the analysis of S19 file.PyQt5, an external Python tool, is used to design the corresponding upper computer in order to update the program online.In order to verify the system performance,the bootloader is tested by upgrading the program of MPC5744P development board which use the upper computer.The test results show that the bootloader can accurately realize the online upgrade of the application program through the interaction with the upper computer, which meets the design requirements.

Keywords:bootloader;heavy tractor controller;the Flash driver;FlexCAN communication;upper computer design

排气管铸造筋结构分析与优化设计

王宝军1,2，孙晶晶1,2，李连升1,2，马庆镇1,2，李德华1,2，侯晓良1,2

1.内燃机可靠性国家重点实验室，山东潍坊261061;2.潍柴动力股份有限公司发动机研究院，山东潍坊261061

摘要：针对发动机排气管出现的裂纹问题，基于热机耦合方法，采用Abaqus软件对故障排气管进行温度场和应力场分析。结果表明：排气管区域应力较大，应力最大的区域与裂纹故障部位相吻合。基于分析结果对故障部位进行优化，将排气管结构由铸造单筋改为管体两侧铸造双筋。对优化方案进行仿真分析，结果表明优化后排气管所受最大应力比改进前降低了87 MPa。发动机装配优化后排气管进行3000 h耐久试验，无开裂故障发生。

关键词：排气管；裂纹；热应力；筋

Analysis and optimal design for cast ribs structure of exhaust pipe

WANG Baojun1,2, SUN Jingjing1,2, LI Liansheng1,2, MA Qingzhen1,2, LI Dehua1,2, HOU Xiaoliang1,2

1.State Key Laboratory of Engine Reliability, Weifang 261061, China; 2.R&D Center,Weichai Power Co., Ltd., Weifang 261061, China

Abstract:In order to solve the crack problem of engine exhaust pipe, the thermalmechanical coupling method is used to analyze the temperature and stress field of the engine exhaust pipe. The results show that the stress of the exhaust pipe is large and the region with the maximum stress value is consistent with the failure position in the test. The structure of exhaust pipe is then changed from casting single rib to casting double rib on both sides of the pipe body, and it is simulated and verified by test. The results show that the maximum stress of the optimized exhaust pipe is reduced by 87 MPa, and no cracking failure occurred in the 3000 h endurance test.

Keywords:exhaust pipe; crack; thermal stress; rib

柴油机喷油器回油管密封失效分析

李杰，于洪涛

潍柴重机股份有限公司，山东潍坊261108

摘要：为解决喷油器回油管密封失效问题，以实际使用过程中出现的喷油器回油管漏油问题为例，根据喷油器回油管的密封原理，采用动力学分析软件Abacus和网格划分工具Hypermesh对喷油器回油结构进行动力学分析，查找失效原因，并提出改进方案。分析结果表明，回油管与喷油器回油锥孔之间的接触密封面积小导致材料塑性变形和密封环线部分翘起是密封失效的原因。改进回油管结构，将回油管密封方式由线接触更改为面接触；同时改进喷油器与回油管的连接套结构，加强喷油器与回油管的紧固；将压紧锥面密封更改为过油螺栓加复合式密封垫圈的密封结构。对改进后的回油管进行500 h耐久试验，结果表明：回油管没有出现漏油故障，改进措施有效。

关键词：喷油器；回油管；密封；失效分析

Failure analysis on seal of fuel injector return pipe of a diesel engine

LI Jie, YU Hongtao

Weichai Heavy Machinery Co., Ltd., Weifang 261108,China

Abstract:In order to solve the problem of fuel injector return pipe seal failure, taking the problem of oil leakage from the return pipe of the injector in actual use as an example ,Abacus and Hypermesh are used for injector oil return structure dynamic analysis to find the cause of failure,and the improvement is proposed. The analysis results show that the sealing failure is caused by the small contact sealing area between the return pipe and the return oil cone hole of the injector, which leads to the plastic deformation and the partial warping of the sealing ring. For improvement, the line contact is changed into surface contact for pipe seal, and the connection sleeve is strengthened. After 500 h endurance test, the improved return pipe shows no oil leakage fault,which shows the improvement is effective.

Keywords: fuel injector; fuel return pipe; seal; failure analysis

某车用柴油机EGR系统应用试验研究

殷海红1，解永辉1，李海庆1，周海磊2,3，肖有强2,3

1.潍坊职业学院机电工程学院，山东潍坊261001；2.内燃机可靠性国家重点实验室，山东潍坊261061；3.潍柴动力股份有限公司，山东潍坊261061

摘要：针对某2级增压车用柴油机的废气再循环(exhaust gas recirculation，EGR)系统，试验研究不同EGR率对发动机经济性和排放性的影响，以及利用EGR实现进气旁通后对发动机性能的影响。试验结果表明：随着EGR率升高，柴油机燃油消耗率和噪声降低；排气温度升高，有助于提高选择性催化还原后处理效率；降低缸内压力，可以提高发动机可靠性。随着EGR率升高，NOx和HC排放明显减低，但会导致CO和烟度排放升高；EGR率低于23%时，CO和烟度排放升高缓慢，EGR率高于23%时，CO和烟度排放升高趋势明显。超低排放发动机应选择高EGR系统，当中冷后进气压力比涡前排气压力高时，EGR阀可作为旁通阀，将进气旁通到增压器涡端，提高增压器的效率和发动机缸内进气量，增加低速时的过量空气系数和低速扭矩。

关键词：柴油机；EGR系统；试验研究

Experimental study on the application of the EGR system of vehicle diesel engine

YIN Haihong1, XIE Yonghui1, LI Haiqing1, ZHOU Hailei2,3, XIAO Youqiang2,3

1. School of Mechanical and Electrical Engineering, Weifang Vocational College, Weifang 262737,China ;2.State Key Laboratory of Engine Reliability, Weifang 261061, China; 3.Weichai Power Co., Ltd., Weifang 261061, China

Abstract: In this paper, the application of exhaust gas recirculation (EGR) in a twostage turbocharged automotive vehicle diesel engine is studied by experiment, the effects of different EGR rates on engine economy and emission, as well as the effects of EGR on engine performance after engine bypass are evaluated. The test results show that with the increase of EGR rate, the fuel consumption and noise of diesel engine decrease. The increase of exhaust temperature is benefit to SCR. Reduced pressure in cylinder can improve engine reliability. At the same time, with the increase of EGR rate, the NOx and HC of diesel decreased significantly, but the CO and smoke increased. When the EGR rate is lower than 23%, the increase is slow, while when the EGR rate is higher than 23%, the increase trend is obvious. For ultralow emission engines, high EGR systems are preferred. After engine bypass can improve the efficiency of the supercharger to improve the air intake in the engine cylinder, and then improve the excess air coefficient at low speed, and improve the low speed torque.

Keywords:diesel engine; EGR system; experimental study

高排温发动机涡轮壳总成流固耦合分析及验证

张金明1，2，张健健1，2 ，马超2，3，苗熠芝1，2，张国栋1，2

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

摘要：为研究涡轮壳废气旁通阀总成卡滞原因和壳体应力分布，通过数值模拟方法建立某型号涡轮增压器的涡轮机有限元分析模型，采用CFX软件对涡轮增压器涡轮壳进行流固耦合分析，仿真分析涡轮壳体温度场分布和应力分布，进行增压器温度场发动机台架试验。结果表明：发动机排温高是涡轮壳废气旁通阀卡滞的原因，设计时应关注涡轮壳高应力区域；仿真与试验结果高度吻合，可为工程应用中分析涡轮壳破坏、阀门总成卡滞等失效模式及增压器总成设计提供技术参考。

关键词：涡轮增压器；涡轮壳总成；计算流体动力学分析；流固耦合；温度场；热应力

Fluidsolid coupling analysis and verification of turbine assembly for high temperature exhaust

ZHANG Jinming1,2, ZHANG Jianjian1,2, MA Chao2,3,MIAO Yizhi1,2, ZHANG Guodong1,2

1.Kangyue Technology Co., Ltd.,Shouguang 262718,China;2.Key Laboratory of Turbocharging System of Machinery Industry, Shouguang 262718, China;3.School of Mechanical and Electrical and Vehicle Engineering,Weifang University, Weifang 261061, China

Abstract:In order to study the cause of the wastegate sticking and the stress distribution of the shell,the finite element model of a certain type of turbocharger is established by numerical simulation method. The CFX software is used to analyze the temperature field and stress of the turbocharger turbine housing by fluidsolid coupling, and the temperature field test of turbocharger based on engine bench is carried out .The results show that the high exhaust temperature is the cause of the wastegate sticking, and the stress analysis shows that the high stress region should be paid attention to when it is been designed,the simulation results are in good agreement with the test results, the simulation results can provide a reference basis for analyzing the failure modes of turbine housing, wastegate assembly and turbocharger assembly design.

Keywords:turbocharger;turbine housing assembly;computational fluid dynamics analysis; fluidsolid coupling;temperature field;thermal stress

飞轮壳螺栓断裂失效分析

曾亮1,2，李文广1,2，张志伟1,2，李雷1,2

1.内燃机可靠性国家重点实验室，山东潍坊261061;2.潍柴动力股份有限公司，山东潍坊261061

摘要：为解决某拖拉机用发动机飞轮壳螺栓断裂故障，通过宏观断口和受力分析、加工质量和材料检验等手段对螺栓进行失效分析，结果表明:螺栓失效原因为低周疲劳断裂，疲劳源位于螺纹牙底，M12螺栓孔附近表面被压溃，螺栓轴力松弛，周围的M10螺栓承受较大的拉压交变应力，产生疲劳，发生断裂。将螺栓承压面改为法兰面，增大接触面积。经计算，优化后螺栓接触区域的面压符合要求。飞轮壳更换新螺栓后市场上未反馈相同故障，改进措施有效。

关键词：飞轮壳；螺栓；断裂

Fracture failure analysis of flywheel housing bolts

ZENG Liang1,2, LI Wenguang1,2, ZHANG Zhiwei1,2, LI Lei1,2

1.State Key Laboratory of Engine Reliability, Weifang 261061, China; 2.Weichai Power Co., Ltd., Weifang 261061, China

Abstract:In order to solve the problem of bolt fracture of flywheel housing for a tractor used diesel, the failure analysis is carried out by means of macro fracture, machining quality, material inspection and force analysis. The results show that the lowcycle fatigue fracture of the bolt occurs, and the fatigue originate from the outer circle of the bolt. Due to the crushing of the surface near the bolt hole of connector M12, the axial force of the bolt is relaxed, and the bolt is easy to loosen. Then the surrounding M10 bolts bear a large alternating stress, resulting in fatigue and fracture. Accordingly, the bolt bearing face is modified to be flange face, and the contact area is increased, the tightening process is also reformulated. The stress is lower after the refinement, and no feedback fault reported from the market.

Keywords: flywheel housing; bolt; fracture

某柴油机空压机支架有限元分析及优化

骆翠芳，陈国强，孙晶晶

潍柴动力股份有限公司发动机技术研究院，山东潍坊261061

摘要：基于有限元分析方法对空压机支架结构设计进行验证，采用Abaqus软件对空压机支架进行模态分析，结果显示：支架安全系数较低，刚度不足；1阶模态频率与激振频率接近，易产生共振。结合拓扑优化方法对刚度不足处进行结构改进设计；对改进后结构进行强度及连接可靠性分析，均满足要求。采用Femfat分析软件对支架进行高周疲劳计算，其最小安全系数不满足限值要求，对支架进行加强筋增厚处理后满足疲劳强度要求。改进后的空压机支架已完成样机开发并通过耐久试验验证，表明优化方法有效。

关键词：空压机支架；有限元方法；优化设计

Finite element analysis and optimization of air compressor bracket

LUO Cuifang, CHEN Guoqiang, SUN Jingjing

R&D Center, Weichai Power Co.,Ltd., Weifang 261061, China

Abstract:The structural design of the air compressor bracket is verified based on the finite element analysis method, and the modal analysis of the air compressor bracket is carried out by using Abaqus software. The results show that the first mode frequency is close to the excitation frequency, easy to produce resonance. The structural topology optimization is carried out, and the direction of the reinforcement rib at the bottom of the bracket is changed. After the optimization, the mode of the bracket meets the requirements. The net strength and connection reliability analysis of the improved structure meet the requirements. The minimum safety factor does not meet the requirements of the limit value when the high cycle fatigue of the bracket is calculated by using the Femfat analysis software, and the fatigue strength requirement is satisfied after the bracket is thickened. The prototype of the improved air compressor bracket has been developed and verified by durability test, and the optimization method is feasible.

Keywords:air compressor bracket; finite element method; optimal design