入口压力对圆形喷管气体射流特性影响的试验研究
彭广宇1,李活1,雷艳2*,仇滔2,吴悦2
1. 湖南交通职业技术学院,湖南 长沙 410132;2.北京工业大学环境与能源工程学院,北京 100124
摘要:针对高压气体直喷射流特性开展试验研究,测试不同入口压力下圆形喷管高压气体射流质量流量;在定容弹上利用纹影法开展气体高压喷射特性试验研究,分析不同入口压力下高压气体射流贯穿距、射流锥角及马赫盘发展特性。结果表明:高压工况下,气体射流达到音速,射流在背景流场形成激波出现马赫盘;随着入口压力的增加,马赫盘区域的总长度和个数先上升后不变再减小;在音速射流工况,近嘴端气体射流同时受到来自流动量和出口马赫盘膨胀的作用,随着射流向前发展,射流前锋面逐渐远离喷管,贯穿速度逐渐降低,而远端由于马赫盘消失,气体的贯穿速度基本保持不变。
关键词:气体射流;圆形喷管;定容弹;马赫盘;贯穿距
Experimental study on the influence of inlet pressure on gas jet characteristics
PENG Guangyu1,LI Huo1,LEI Yan2*,QIU Tao2,WU Yue2
1.Hunan Communication Polytchnic,Changsha 410132,China;
2.College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China
Abstract:This paper presents an experimental investigation on the jet characteristics of highpressure gas direct injection. The highpressure jet mass flow is tested under varied injection pressure. In addition, the optical experimental study of highpressure gas injection characteristics is conducted by using the shadow method based on a constantvolume bomb test system, and the gas jet characteristic parameters such as the gas jet penetration distance, jet cone angle and Mach disk are analyzed under condition of varied inlet pressure. The results show that under condition of highpressure injection, the gas jet velocity becomes sonic speed, and Mach disks appear in the background flow field. As the injection pressure increases, the total length and number of the Mach disks region have the change trend of first rising and then decreasing. As for the sonic gas jet, the gas jet in the nearnozzle zone is affected by the gas flow velocity at the nozzle outlet and the Mach disk at the same time. As the gas jet moves forward and the jet front gradually moves away from the nozzle, the gas penetration velocity decreases gradually. In the far zone to the nozzle, where the Mach disk disappears, the gas penetration velocity basically remains unchanged.
Keywords:gas jet; cylindrical nozzle; constantvolume bomb; Mach disk; jet penetration distance
不同余热对有机朗肯循环余热回收效果的影响
王培伦1,2, 孔祥花1,2, 李敏1,2, 隋博1,2, 文志永1,2, 李志杰1,2
1. 内燃机可靠性国家重点实验室,山东 潍坊 262061;2. 潍柴动力股份有限公司,山东 潍坊 261061
摘要:针对以环戊烷和R245fa为工质的有机朗肯循环(organic Rankine cycle, ORC)系统进行研究。分析蒸发压力、过热度、过冷度、回热度(回热器液态工质进出口温差)、膨胀机效率和膨胀比等对ORC系统工作效率的影响,缸套水余热和中冷器余热对ORC系统功率提升的影响。研究发现:蒸发压力、膨胀机的效率和膨胀比对ORC系统工作效率的影响较大;通过合理配比2个ORC循环中烟气的热量,能显著增加系统的输出功率;中冷器布置在回热器上游时中冷器余热对系统工作效率的提高比中冷器布置在下游时更好。
关键词:有机朗肯循环;柴油机余热;环戊烷和R245fa
The influence of different waste heat on waste heat recovery performance based on organic Rankine cycle
WANG Peilun1,2, KONG Xianghua1,2, LI Min1,2,SUI Bo1,2, WEN Zhiyong1,2, LI Zhijie1,2
1. State Key Laboratory of Engine Reliability, Weifang 262061, China;
2. Weichai Power Co., Ltd., Weifang 261061, China
Abstract:For the organic Rankine cycle (ORC) system, cyclopentane and R245fa are selected to analyze the effects of evaporation pressure, overheating, overcooling, reheating (regeneration thermoelectric inlet and outlet temperature difference), expander efficiency and expansion ratio on the ORC system efficiency. Among them, the evaporation pressure, expander efficiency and the expansion ratio have a great influence. The effect of the waste heat of the liner water and the waste heat of the intercooler on the power boost of the Rankine cycle system is also studied. It is found that the proper heat output ratio of flue gas in the two ORC can significantly increase the output power of the system. Moreover, the waste heat of the intercooler is better in the upstream of the regenerator than that in the downstream.
Keywords:organic Rankine cycle; diesel engine waste heat; cyclopentane and R245fa
船用中速柴油机气门热负荷降低研究
朱涛1,2,杨栋1,2,朱娜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:在当前配置基础上,利用一维和三维仿真,研究某船用中速柴油机不同高压油泵凸轮型线、喷油器喷孔夹角、活塞顶型线对降低燃油消耗率和气门热负荷的影响。研究结果表明,通过优化油泵凸轮型线和活塞顶型线以及选择小的喷孔夹角,燃油消耗率和气门热负荷分别降低3%和35%,排气门开启时的缸内燃气温度降低50 ℃,有效地降低缸内热负荷,提高气缸盖、气门等零部件可靠性,同时NOx排放水平基本不变,避免对大气环境的危害。
关键词:船用中速柴油机;燃油消耗率;气门热负荷;可靠性
Research on valve thermal load reduction of marine mediumspeed diesel engine
ZHU Tao1,2, YANG Dong1,2, ZHU Na1,2
1.State Key Laboratory of Engine Reliability, Weifang 261061 , China; 2.Weichai Power Co., Ltd., Weifang 261061, China
Abstract:Based on a marine mediumspeed diesel engine, the effects of different highpressure fuel pump cam profiles, injector nozzle angles, and piston crown profiles on fuel consumption and valve thermal load are studied. The results show that about 3% fuel consumption rate and 35% valve thermal load can be reduced by optimized matching. When the exhaust valve is opened, the gas temperature in the cylinder is reduced by 50 ℃, which effectively reduces the thermal load in the cylinder and improves the reliability of some critical parts such as cylinder head and valves. At the same time, the NOx emission level is kept basically unchanged to avoid harm to the atmospheric environment.
Keywords:marine mediumspeed diesel engine; fuel consumption rate; valve thermal load; reliability
缸内直喷发动机正时系统设计与验证
尹子明1, 余伟1, 张春丽1, 黄黎明2
1.奇瑞汽车股份有限公司动力系统技术中心,安徽 芜湖 241000;
2.博格华纳汽车零部件有限公司,上海 201100
摘要:对某直喷汽油机正时系统进行仿真计算和试验验证。优化凸轮轴设计,调整燃油泵凸轮相对凸轮轴凸轮的角度,将燃油泵扭矩峰值滞后凸轮轴扭矩峰值的角度由72°调整到125°,使合成扭矩峰值最小,降低对正时系统负载影响。仿真结果表明,链条张力和张紧器柱塞位移均达到设计标准,系统运行稳定;发动机正时系统功能测试结果表明,凸轮轴优化后,链条对固定导轨的振动加速度从270g(g为重力加速度)降低到100g;链条最大张力满足强度要求;张紧器柱塞位移在发动机转速范围内小于3 mm,稳定工况下小于0.5 mm。仿真和测试结果接近,优化后的凸轮轴链条负载大幅度降低,张紧器工作稳定,能够控制整个系统平稳运行,凸轮轴优化合理,达到了设计目标。
关键词:缸内直喷;高压油泵;正时系统;合成扭矩;凸轮轴优化
Design and validation on GDI engine timing drive system
YIN Ziming1, YU Wei1, ZHANG Chunli1, HUANG Liming2
1.Powertrain Technology Center of Chery Automobile Co., Ltd., Wuhu 241000, China;
2. BorgWarner Automotive Components Co., Ltd., Shanghai 201100, China
Abstract:In terms of a fuel pump used for gasoline direct injection (GDI) engine, the angle between fuel pump lobe and camshaft lobe is adujsted, and the fuel pump peak torque retarded camshaft peak torque is set from 72° to 125°,in order to minimize the resultant torque and reduce the effect to chain load. By numerical simulation of timing drive system, two main features,chain force and piston motion satisfy design specification. The test results show the optimized camshaft reduce the vibration acceleration of chain guide from 270 g to 100 g, which means the adjusted fuel pump lobe angle is effective. The chain drive test results show, the chain max force meet the strength requirement and the tensioner piston motion less than 3 mm for all engine speeds and less than 0.5 mm in the steady speed. Both the simulation and test results show that the chain load reduced with optimized camshaft and tensioner work steadily, theoptimized camshaft is reasonable and the system runs smoothly which meet the initial design target.
Keywords:GDI;high pressure fuel pump;timing drive system;resultant torque;camshaft optimization
船用高强化柴油机冷却系统优化设计与试验研究
刘晶晶1,2,陈秀梅1,2,周萌1,2,李光辉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:基于降低成本和轻量化需求,对某高强化船用柴油机冷却系统进行优化设计,取消低温回路水泵,高、低温冷却回路共用同一水泵。对优化后冷却系统的流量分布、温度分布、压力分布和整机热平衡等进行试验验证。结果表明,冷却系统各部件的进出水温差和压降分布合理,整机热平衡热量分布满足性能要求,减少了系统附件,降低了制造成本和整机质量。
关键词:热负荷;高强化柴油机;冷却系统;试验研究
Optimization design and experimental study on the cooling system of a highlystrengthened marine diesel engine
LIU Jingjing1,2,CHEN Xiumei1,2,ZHOU Meng1,2,LI Guanghui1,2
1.State Key Laboratory of Engine Reliability, Weifang 261061, China; 2.Weichai Power Co., Ltd., Weifang 261061, China
Abstract:Based on the requirements of cost reduction and lightweight, the cooling system of a highlystrengthened marine diesel engine is optimized.The low temperature loop water pump is cancelled, alternatively, the high and low temperature cooling circuit shared the same water pump. The flow distribution, temperature distribution, pressure distribution and heat balance of the whole machine are tested and verified. The results show that the distribution of water temperature difference and pressure drop of each component is acceptable, the heat balance meets the performance requirements of the whole machine, when the accessories are reduced. Then the manufacture cost and the quality of the whole machine are reduced.
Keywords:thermal load;highlystrengthened diesel engine;cooling system;experimental study
柴油机水压波动分析及机油冷却器盖结构优化
李正现1,2,刘伟达1,2,刘近报1,2,程祥军1,2,高进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:为解决市场配套柴油机机油冷却器盖频繁出现裂纹的故障,分析2种不同流量的水泵,测量不同转速下水泵的水压及水压波动。测量结果表明:水流量大、转速高的水泵易引起水压大幅度波动,最大水压超过500 kPa,波动幅度约为250 kPa。对测量的水压进行有限元分析可知,水压及水压波动大是导致机油冷却器盖裂纹的根本原因。对机油冷却器盖进行改进,增大倒角,计算分析表明改进后的机油冷却器盖可承受500 kPa水压。改进后机油冷却器盖在使用中未出现裂纹现象。计算分析及使用结果表明:在满足散热、冷却和热平衡等情况下,应优先选用流量小的水泵;用瞬时水压代替平均水压,分析结果更准确;防冻液刚进入机体的位置为水压测点,测量结果更精确。
关键词:水压;波动;机油冷却器盖;节温器;冷却系统;水泵
Analysis of water pressure fluctuation of a diesel engine and optimization of oil cooler cover
LI Zhengxian1,2, LIU Weida1,2, LIU Jinbao1,2,
CHENG Xiangjun1,2, GAO Jin1,2
1.State Key Laboratory of Engine Reliability,Weifang 261061, China;
2. R&D Centre,Weichai Power Co.,Ltd., Weifang 261061, China
Abstract:In order to slove the crack failure of oil cooler cover frequently occured in a diesel engine ,two pumps with different flow are selected for analysis. The pressure and fluctuation of pressure of water are measured at different speeds. The measurement results show that pumps with larger water flow and higher speed are easy to cause larger fluctuation of water pressure.The maximum water pressure could exceed 500 kPa, and the fluctuation rang is 250 kPa.Finite element analysis is used and it is found that cracks appear because of such high water pressure and water pressure fluctuation. Increasing the chamfering of the cold cover could improve its performance under 500 kPa water pressure.No cracks appear in the oil cooler cover after use. Calculation, analysis and application results show that considering heat dissipation,cooling and heat balance,water pump with small flow is preferred.Replacing average water pressure with instantaneous water pressure will get more accurate analysis results.The position near the antifreeze inlet of the water pump could give reliable data for pressure measurement.
Keywords:hydraulic pressure; fluctuation; oil cooler cover;thermostat; cooling system; water pump
针阀升程对共轨喷油器稳定性的影响
李春晖,吴小军,奚星,徐春龙
中国北方发动机研究所燃油系统研究室,天津 300400
摘要:为研究针阀升程对某柴油机共轨喷油器喷油稳定性的影响,在高压共轨性能试验台上对不同针阀升程的喷油器进行性能测试,研究改变针阀升程对共轨喷油器不稳定工况点的影响;根据试验结果搭建AMESim仿真模型,仿真分析不稳定工况点的针阀运动状态。研究发现,增大针阀升程不利于喷油器稳定喷油,增大针阀在最大升程处的维持时间有利于提高喷油器稳定性。研究结果为该型喷油器改进设计提供了支撑。
关键词:共轨喷油器;喷油稳定性;仿真
The effect of needle valve lift on the stability of common rail injector
LI Chunhui, WU Xiaojun, XI Xing, XU Chunlong
Fuel System Research Division, China North Engine Research Institute,Tianjin 300400,China
Abstract:In order to study the effect of needle valve lift on the stability of common rail injector for a diesel engine, the performance of the injector with different needle valve lift is tested on the EFS test bench. The influence of the maximum lift of needle valve on the unstable operating point of a common rail injector is obtained. The AMESim simulation model is built according to the test result, and the movement of needle valve on the unstable operating points are analyzed. The result indicates that increasing the lift of needle valve is not conducive to improving the injection stability, and increasing the holding time of the needle valve at the maximum lift is conducive to improve the injection stability.
Keywords:common rail injector;injection stability;simulation
某静音机组热管理一维与三维耦合仿真
尹晓青1,仇海龙1,王继勇1,高亚南2,葛西坤1
1.潍柴重机股份有限公司,山东 潍坊 261061;2.潍柴动力股份有限公司,山东 潍坊 261061
摘要:以某静音机组为研究对象,采用一维与三维耦合仿真方法对机组热管理进行分析计算,研究一维与三维耦合仿真的准确性。在利用三维软件Fluent完成机舱内空气流动、风速等参数计算的基础上,利用一维软件Kuli对模型进行标定,得到一维中冷器、热交换器的出水温度分别为55.40、87.51 ℃。进行机组热平衡试验,得到中冷器、热交换器出水温度分别54.40、88.48 ℃。仿真计算与试验结果误差较小,表明一维与三维耦合仿真精确性较高,可为后续机组热平衡的设计及仿真提供参考。
关键词:静音机组;机舱;热管理;一维仿真;三维仿真;耦合
Onedimensional and three-dimensional coupling simulation of thermal management of a silent unit
YIN Xiaoqing1, QIU Hailong1, WANG Jiyong1, GAO Ya′nan2, GE Xikun1
1.Weichai Heavy Machinery Co., Ltd., Weifang 261061,China; 2.Weichai Power Co., Ltd., Weifang 261061,China
Abstract:Taking a silent unit as an example, onedimensional and threedimensional coupling simulation method are used to analyze and calculate the cooling performance of the unit, and the simulation results are verified by experiments. The threedimensional software Fluent is used to complete the calculation of air flow and wind speed in the cabin. Then based on the threedimensional simulation calculation results, the model iscalibrated using the onedimensional software Kuli, and the outlet water temperature of intercooler and heat exchanger are 5540 ℃ and 87.51 ℃. Through the heat balance test, the outlet water temperature of intercoder and heat exchanger is 5440 ℃ and 88.48 ℃. The comparison between the calculation and the test shows that the error between the two is small, and within the acceptable range, which provides a reference for the subsequent design and simulation of the unit thermal balance.
Keywords:silent unit; engine room; thermal management; onedimensional simulation; threedimensional simulation; coupling
柴油机配气机构摩擦仿真建模
李云华1,2,陈火雷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,山东 潍坊 261061
摘要:为深入研究低摩擦技术在柴油机上的应用,基于GTuite软件搭建柴油机配气机构摩擦仿真模型,利用柴油机摩擦功拆解试验得到的配气机构及各部分摩擦功,对模型进行校核,通过试验和仿真对比,验证仿真模型的准确性。研究气门压差对摩擦功计算结果的影响,结果表明:摩擦模型准确,可以用于配气机构进一步研究;在计算配气机构摩擦功时,必须考虑气门压差对摩擦功计算的影响。
关键词:配气机构;气门压差;摩擦仿真;建模
The friction simulation model of valve train of diesel engine
LI Yunhua1,2, CHEN Huolei1,2, XU Xianfa1,2
1.State Key Laboratory of Engine Reliability, Weifang 261061, China; 2.Weichai Power Co., Ltd., Weifang 261061, China
Abstract:In order to deepen the application of low friction technology in diesel engines, the friction simulation model of diesel engine valve distribution mechanism is built based on the GTSuite software. The model is checked by motoring friction work of valvetrain and the accuracy of the model is verified through the comparison of test and simulation. Further studies on the valve pressure difference on the influence of friction is also carried out. The results show that the friction model is accurate and can be used for further research of the valve distribution mechanism. In calculating the friction work of the valve, the influence of valve pressure difference on the calculation of friction work must be considered.
Keywords:valve train; valve pressure difference; friction simulation; modeling
基于DoE的农用高压共轨柴油机优化设计
孙良良,冯洪庆
中国石油大学(华东)新能源学院,山东 青岛 266580
摘要:以某农用高压共轨柴油机为研究对象,将应用试验设计(design of experiment, DoE)与数值仿真相结合,对柴油机的结构参数进行优化仿真。选取柴油机进气系统参数与配气相位作为设计变量,通过试验获得设计目标的响应特性,拟合得到响应面近似模型。应用遗传预测算法进行多参数多目标优化求解,得到柴油机常用工况下的最佳设计参数。研究结果表明:设计参数优化后,柴油机的有效扭矩提高了2.6%,有效比油耗降低了25%,排气温度降低了16.7%。
关键词:农用柴油机;进气系统;配气相位;数值仿真;DoE
The optimization design of a highpressure common rail diesel engine used for agriculture based on DoE
SUN Liangliang, FENG Hongqing*
College of New Energy,China University of Petroleum,Qingdao 266580, China
Abstract:A diesel engine used for agriculture is selected to optimize the structural parameters by DOE combining with numerical simulation.Several structural parameters is selected as design variables and the response characteristic of the design target is obtained through the experiment. The response surface approximation model is obtained by fitting. Multiparameter and multiobjective optimization is carried out by genetic algorithm and the optimal design parameters of engine common working conditions is obtained. The results show that the effective torque is increased by 2.6%, the effective specific fuel consumption is reduced by 2.5%, and the exhaust temperature is reduced by 16.7%.
Keywords:agricultural engine; intake system; valve timing; numerical simulation; DoE
柴油机活塞裙面型线设计分析
宋娇1,2,赵忠诚1,2,田新伟1,2,江雨晨3,胡勇3
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;3.山东大学能源与动力工程学院,山东 济南 250061
摘要:为得到活塞裙面型线设计中不同因素的影响权重及显著性,选取活塞裙面型线中凸型线顶端内缩量、底端内缩量、中凸点高度及变椭圆度系数等参数,设计正交试验方案,应用三维结构动力学分析软件,研究不同活塞裙面型线设计方案下的活塞裙部-缸套间的润滑及振动特性。分析结果表明:活塞裙顶端内缩量对最小油膜厚度存在显著影响,中凸点高度和底端变椭圆度系数为摩擦功耗的影响因子,而顶端变椭圆度系数对缸套振动特性的影响高度显著;综合考虑活塞裙部润滑特性和缸套振动特性,得到活塞裙面型线最优设计方案,活塞裙底部缩进量为0.08 mm,活塞裙顶端内缩量为0.15 mm,中凸点高度为27 mm,变椭圆度系数a为0.45,变椭圆度系数b为0.002 8。
关键词:活塞裙面型线;柴油机;润滑特性;振动特性
Analysis and design of diesel engine piston skirt profile
SONG Jiao1,2, ZHAO Zhongcheng1,2, TIAN Xinwei1,2, JIANG Yuchen3, HU Yong3
1.State Key Laboratory of Engine Reliability, Weifang 261061,China;2.Weichai Power Co., Ltd., Weifang 261061,China;3.School of Energy and Power Engineering, Shandong University, Jinan 250061,China
Abstract:In order to obtain the influence weight and significance of different factors in the design of piston skirt profile, the orthogonal test scheme is designed by selecting the parameters such as the top shrinkage, the bottom end shrinkage, the height of middle convex point and the variable ellipticity coefficient. The lubrication and vibration characteristics between piston skirt and cylinder sleeve under different design schemes of piston skirt profile are studied by using 3D structural dynamics analysis software.The results show that the reduction of the piston skirt top has a significant effect on the minimum oil film thickness, the height of the middle convex point and the variable ellipticity coefficient of the bottom end are the influence factors of the friction power consumption, while the top variable ellipticity coefficient has a significant impact on the vibration characteristics of the cylinder liner.Considering the lubrication characteristics of the piston skirt and the vibration characteristics of the cylinder liner, the optimal design scheme of the piston skirt contour is obtained. The reduction of the bottom of the piston skirt is 0.08 mm, the internal shrinkage of the top of the piston skirt is 015 mm, the height of the middle convex point is 27 mm, the variable ellipticity coefficient a is 0.45, and the variable ellipticity coefficient b is 0.002 8.
Keywords:piston skirt profile; diesel engine; lubrication characteristic; vibration characteristic
排气管布置形式对双增压发动机性能影响的计算分析
刘俊龙1,2,耿国芳1,2,庞斌1,2,冯新刚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:为了提高直列8缸机的排气能量利用率,利用AVL-Boost软件建立某直列8缸柴油机匹配2台增压器的计算模型,分析3种排气管布置方案下的各缸排气流量、涡轮增压器效率、各缸均匀性、发动机性能等参数。分析结果表明:布置方案A的整体性能较好、各缸排气干扰和回流小、废气能量利用率高,但各缸均匀性略差;与方案B、C相比,方案A的整机油耗率降低5~8 g/(kW·h),涡轮增压器效率提高4%~6%,泵气损失减小60~100 kPa,充气效率提高3%~4%。
关键词:双增压发动机;排气管;性能;仿真计算
Calculation and analysis of the influence of exhaust pipe layout on the performance of dualturbochargers engine
LIU Junlong1,2, GENG Guofang1,2, PANG Bin1,2, FENG Xin′gang1,2
1.State Key Laboratory of Engine Reliability, Weifang 261061 China;
2.Weichai Power Co., Ltd., Weifang 261061 China
Abstract:In order to use more exhaust energy,AVL-Boost is used to establish a calculation model of an inline 8cylinder diesel engine with dual turbochargers, and the simulation is done with three different exhaust pipe layouts,the parameters such as exhaust flow of each cylinder, turbocharger efficiency, uniformity of each cylinder and engine performance under three kinds of exhaust pipe layout schemes are analyzed. The analysis results show that overall performance of layout A is better, the exhaust interference and backflow of each cylinder is smaller, the exhaust energy utilization rate is higher, but the uniformity of each cylinder is slightly worse.Compared with layout B and C, the fuel consumption rate of the whole machine in layout A is 5~8 g/(kW·h) lower, the turbocharger efficiency is 4%~6% higher, the pump gas loss is 60~100 kPa lower, and the gas charging efficiency is 3%~4% higher.
Keywords:dualturbochargers engine; exhaust pipe; performance; simulation calculation
虚拟装配技术下发动机曲轴正时相位空气间隙优化分析
刘泽涛1,2,魏红玲1,2,徐庆增1,2,宋广迎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:通过研究公差分析原理及流程,利用VSA软件建立发动机曲轴正时相位空气间隙虚拟装配模型,采用蒙特卡洛法进行累积公差仿真分析,研究初始设计阶段零件特征对空气间隙的影响和贡献率。结果表明:虚拟装配技术可以在产品设计阶段避免装配时的公差累积,为产品公差再设计提供解决方案,缩短产品开发周期,为产品设计提供准确可靠的依据。
关键词:虚拟装配;曲轴正时相位;空气间隙公差分析;发动机;VSA软件
Analysis and optimization of air clearance of engine crankshaft timing phase based on virtual assembling technology
LIU Zetao1,2, WEI Hongling1,2, XU Qingzeng1,2, SONG Guangying1,2
1.State Key Laboratory of Engine Reliability, Weifang 261061,China;
2.Weichai Power Co., Ltd., Weifang 261061,China
Abstract:By studying the principle and process of tolerance analysis,VSA software is used to establish the virtual assembly model of engine crankshaft timing phase air gap, and Monte Carlo method is used to carry out the cumulative tolerance simulation analysis,the influence and contribution rate of part characteristics on air gap in the initial design phase are studied. The results show that the virtual assembly technology can avoid tolerance accumulation during assembly during product design stage, provide solutions for product tolerance redesign, shorten product development cycle, and provide accurate and reliable basis for product design.
Keywords:virtual assembly; crankshaft timing phase; air gap tolerance analysis; engine; VSA software
基于Madymo的正面碰撞驾驶员侧约束分析
韩广德,杨君,高岩飞,薛文杰,郭峻宇
山东交通学院汽车工程学院,山东 济南 250357
摘要:选取道路交通事故中比例较高的车辆正面碰撞事故,通过Madymo仿真软件,建立由车体、假人、安全带和安全气囊4部分模型组成的驾驶员侧约束系统模型,对国内外不同性别、身高的假人模型进行正面碰撞仿真试验。通过不同假人头部和胸部的伤害程度对比,发现现有驾驶员侧约束系统对中国人中体型较小和体重较轻的人群保护效果较差,该分析为车辆约束系统的设计及优化提供参考依据。
关键词:Madymo;驾驶员侧;正面约束系统
Driverside constraint analysis in frontal collision based on Madymo
HAN Guangde, YANG Jun, GAO Yanfei, XUE Wenjie, GUO Junyu
School of Automotive Engineering, Shandong Jiaotong University, Jinan 250357,China
Abstract:The vehicle frontal collision accidents with a high proportion in road traffic accidents are selected and the driverside restraint system model consisting of the vehicle body model, dummy model, seat belt model and airbag model is established through Madymo simulation software. The frontal collision simulation test is conducted for dummies of different genders and heights at home and abroad. By comparing the injury degree of the head and chest of different dummies, it is found that the existing driverside restraint system has poor protective effect on the small and light weight population in China, which provides reference for the design and optimization of vehicle restraint system.
Keywords:Madymo; driverside; frontal restraint system
DPF超声波清洗与高温气体再生技术研究
邵清1,2,袁彬1,2,翟浩1,2,李晓辉1,2,王文全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:研究超声波清洗与高温气体再生技术对柴油颗粒捕集器(diesel particulate filter, DPF)性能的影响,制定试验方法与策略,对不同规格DPF进行超声波清洗与高温气体再生试验。背压试验发现,超声波清洗后DPF压降增加2.7%,高温气体再生处理后压降增加4.3%;超声波清洗处理与高温气体再生处理DPF的起燃温度最大降幅为1.9%。活性试验发现,400 ℃时2种处理方法的最大转化率降低1.6%。经过上述2种方法处理后的DPF背压与合成气体台架试验中载体涂层活性变化均在5%以内,无明显差异。
关键词:颗粒捕集器;超声波清洗;高温气体再生;碳烟
Study on ultrasonic cleaning and high temperature gas regeneration of DPF
SHAO Qing1,2, YUAN Bin1,2, ZHAI Hao1,2, LI Xiaohui1,2, WANG Wenquan1,2
1.State Key Laboratory of Engine Reliability, Weifang 261061, China; 2.Weichai Power Co., Ltd., Weifang 261061, China
Abstract:In order to verify the effect of ultrasonic cleaning and hightemperature gas regeneration DPF technology, different specifications of DPFs are tested. Pressure drop is increased by 27% after ultrasonic cleaning, and increased by 43% after high temperature gas regeneration. The maximum reduction of light off activation characteristic after ultrasonic cleaning and high temperature gas regeneration is 19%, and the maximum conversion rate is decreased by 16% at 400 ℃. The results show that there is no significant impact on DPF pressure drop value and SGB activity after ultrasonic cleaning and high temperature gas regeneration treatment.
Keywords:DPF; ultrasonic cleaning; hightemperature gas regeneration; soot
内部EGR对自吸柴油机性能影响的仿真研究
孙振宇1,2,庞斌1,2,周鹏1,2,沈健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:采用一维仿真、三维仿真相互提供边界的方法,研究内部废气再循环(exhaust gas recirculation,EGR)对柴油机性能的影响。以原机试验数据作为输入,建立一维仿真模型,模拟配气相位变化对换气过程的影响;将换气过程对应的进气边界赋值给三维仿真模型,模拟内部EGR对燃烧的影响,输出放热率;将放热率代入一维仿真模型,重新评估配气相位对性能的影响。仿真结果表明:内部EGR会降低泵气损失,但造成缸内热负荷增加;排气门二次开启的各缸EGR率一致性优于进气门二次开启;采用内部EGR可以在不增加NOx排放的基础上,通过提升喷油压力,达到降低油耗和碳烟的目的,并降低机油老化的风险。
关键词:柴油机;内部EGR;性能仿真
Simulation of the effect of internal EGR on performance of naturally aspirated diesel engine
SUN Zhenyu1,2, PANG Bin1,2,ZHOU Peng1,2,SHEN Jian1,2
1.State Key Laboratory of Engine Reliability, Weifang 261061, China;2. Weichai Power Co.,Ltd., Weifang 261061,China
Abstract:The influence of internal exhaust gas recirculation (EGR) on the performance of diesel engine is studied using combined 1D and 3D simulation technology. A 1D simulation model is established to simulate the influence of the phase change of the distributor on the ventilation process with the original test data as input. The inlet boundary corresponding to the ventilation process is assigned to the 3D simulation model to simulate the internal EGR′s influence on combustion and calculate the heat release rate, which is substituted into the 1D simulation model to reevaluate the influence of the distribution phase on the performance. The simulation results show that internal EGR can reduce the pumping loss, but heat load in the cylinder increases. The consistency of EGR rate of each cylinder with dual opening of exhaust valve is better than that of intake valve. Internal EGR can reduce fuel consumption and smoke by increasing injection pressure without increasing NOx emission, and reduce the risk of oil aging.
Keywords:diesel engine ; internal EGR;performance simulation