DCT汽车起步过程离合器热负荷仿真研究
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摘要
双离合器自动变速器(DCT)是在电控机械式自动变速(AMT)技术基础上发展的一种新型自动变速器,它具备手动变速器结构简单、传动效率高的特点,并且克服了AMT换档过程动力中断的弱点,换档迅速,综合了AMT的优势和液力自动变速器AT动力换挡的优点,具备了很好的换挡品质和车辆动力性、经济性,已成为汽车自动变速器新的发展方向,具有广阔的市场前景。
目前DCT采用的离合器有干式和湿式两种结构型式。干式双离合器与湿式双离合器相比具有结构简单、传动效率高、成本低的优点,但对于干式离合器换档时为避免动力中断,两个离合器切换过程中必然存在扭矩传递的重叠,从而导致离合器大量滑摩热量的产生。离合器摩擦片的磨损随压盘温度的升高而增大,当压盘工作表面温度超过180～200?C时,摩擦片磨损急剧增加,而温升取决于干式离合器的热容量和热量耗散能力,因此温升控制问题是影响干式双离合器承载能力和寿命的关键之一。
本文针对装有干式双离合器自动变速器的车辆起步过程中离合器的滑摩温升问题进行了研究,主要内容如下:
①在分析干式离合器的摩擦材料、摩擦类型、摩擦过程和失效形式的基础上,对干式离合器主要性能参数及摩擦过程中热负荷评价指标进行了计算;
②制定了双离合器车辆起步控制策略,对DCT传动系统进行动力学分析,建立发动机、双离合器、整车数学模型和离合器滑摩功数值仿真模型。利用MATLAB/SIMULINK对采用干式双离合器自动变速汽车不同载荷普通路面起步和爬坡起步过程进行仿真,动态求解得到滑摩功曲线;
③从传热学的基本理论出发,求解离合器摩擦副热分析边界条件,利用ANSYS软件对双离合器摩擦副瞬态温度场进行有限元建模和仿真;
④通过对摩擦副温升过程的研究,分析了离合器摩擦副温升影响因素。提出了有利于降低温升,提高承载能力和使用寿命的干式双离合器结构设计方案和冷却系统与装置的设计方案;
⑤对干式离合器温升测试方法和摩擦磨损性能进行了研究,设计了干式离合器模拟测试系统,并制定了实验测试方案和步骤。
Dual-clutch Automatic Transmission (DCT) is a new automatic transmission developed on the basis of the electronically controlled Mechanical Automatic Transmission ( AMT) technology. DCT has simple, efficient transmission characteristics like Manual Transmission(MT) and can shift rapidly, which overcomes the AMT weakness of shifting power disrupts. DCT has become the new direction for the development of broad market prospects for a vehicle automatic transmission, because of the AMT advantages and the AT advantages of power shift, the good shift quality and dynamic and economic vehicle nature of the DCT.
There are two kinds of clutches currently used in a DCT, wet and dry. Dry clutches have the advantages of simple structure, high transmission efficiency and low cost compared with wet clutches. But in order to avoid power interruption when dry clutch shift, the two clutchs switch unavoidably to produce the torque transmission overlap, then leading to a lot of sliding friction heat. The wear of the friction disk increases with the pressure-plate temperature-rise. When the work surface temperature of the pressure is over 180 ~ 200 ? C, friction-wears increases sharply. Temperature-rise depends on the heat capacity and heat dissipation capacity of dry clutch. So the heat dissipation is a key to DCT carrying capacity and working life.
The paper studies the sliding friction process of clutch with temperature-rise issues, produced in dry dual clutch automatic transmission when vehicles start. The main contents are as followed:
①Dry clutch friction materials, the type of friction and friction process were explained. Key performance parameters and the failure mode of dry clutch, evaluation parameters of heat load in the process of friction are calculated;
②The start control strategy using two clutches is made. There is dynamic analysis for DCT transmission system. Mathematical models of the engine, double-clutch, and the slipping work are established. The car in different loads on ordinary road when doing climbing starting work is simulated under MATLAB / SIMULINK, then the slipping work curve produced under different work conditions;
③Based on the heat transfer theory, boundary conditions for thermal analysis of clutch friction are acquired. The finite element models of clutch friction disk and the pressure plate are established. Temperature rising of them is acquired and their transient temperature field distribution is obtained using ANSYS software;
④Through the front studies temperature rising of pairs, we determine the influence factors of temperature rise of clutch friction pairs. It is useful for reducing the temperature rising, carrying capacity and enhancing the service life of dry type structure of dual clutch design and cooling systems and equipment design;
⑤Temperature-rise and wear testing system is studied.The dry clutch simulation test system is designed.The basic structure of test bench and the testing process are established.
目前DCT采用的离合器有干式和湿式两种结构型式。干式双离合器与湿式双离合器相比具有结构简单、传动效率高、成本低的优点,但对于干式离合器换档时为避免动力中断,两个离合器切换过程中必然存在扭矩传递的重叠,从而导致离合器大量滑摩热量的产生。离合器摩擦片的磨损随压盘温度的升高而增大,当压盘工作表面温度超过180～200?C时,摩擦片磨损急剧增加,而温升取决于干式离合器的热容量和热量耗散能力,因此温升控制问题是影响干式双离合器承载能力和寿命的关键之一。
本文针对装有干式双离合器自动变速器的车辆起步过程中离合器的滑摩温升问题进行了研究,主要内容如下:
①在分析干式离合器的摩擦材料、摩擦类型、摩擦过程和失效形式的基础上,对干式离合器主要性能参数及摩擦过程中热负荷评价指标进行了计算;
②制定了双离合器车辆起步控制策略,对DCT传动系统进行动力学分析,建立发动机、双离合器、整车数学模型和离合器滑摩功数值仿真模型。利用MATLAB/SIMULINK对采用干式双离合器自动变速汽车不同载荷普通路面起步和爬坡起步过程进行仿真,动态求解得到滑摩功曲线;
③从传热学的基本理论出发,求解离合器摩擦副热分析边界条件,利用ANSYS软件对双离合器摩擦副瞬态温度场进行有限元建模和仿真;
④通过对摩擦副温升过程的研究,分析了离合器摩擦副温升影响因素。提出了有利于降低温升,提高承载能力和使用寿命的干式双离合器结构设计方案和冷却系统与装置的设计方案;
⑤对干式离合器温升测试方法和摩擦磨损性能进行了研究,设计了干式离合器模拟测试系统,并制定了实验测试方案和步骤。
Dual-clutch Automatic Transmission (DCT) is a new automatic transmission developed on the basis of the electronically controlled Mechanical Automatic Transmission ( AMT) technology. DCT has simple, efficient transmission characteristics like Manual Transmission(MT) and can shift rapidly, which overcomes the AMT weakness of shifting power disrupts. DCT has become the new direction for the development of broad market prospects for a vehicle automatic transmission, because of the AMT advantages and the AT advantages of power shift, the good shift quality and dynamic and economic vehicle nature of the DCT.
There are two kinds of clutches currently used in a DCT, wet and dry. Dry clutches have the advantages of simple structure, high transmission efficiency and low cost compared with wet clutches. But in order to avoid power interruption when dry clutch shift, the two clutchs switch unavoidably to produce the torque transmission overlap, then leading to a lot of sliding friction heat. The wear of the friction disk increases with the pressure-plate temperature-rise. When the work surface temperature of the pressure is over 180 ~ 200 ? C, friction-wears increases sharply. Temperature-rise depends on the heat capacity and heat dissipation capacity of dry clutch. So the heat dissipation is a key to DCT carrying capacity and working life.
The paper studies the sliding friction process of clutch with temperature-rise issues, produced in dry dual clutch automatic transmission when vehicles start. The main contents are as followed:
①Dry clutch friction materials, the type of friction and friction process were explained. Key performance parameters and the failure mode of dry clutch, evaluation parameters of heat load in the process of friction are calculated;
②The start control strategy using two clutches is made. There is dynamic analysis for DCT transmission system. Mathematical models of the engine, double-clutch, and the slipping work are established. The car in different loads on ordinary road when doing climbing starting work is simulated under MATLAB / SIMULINK, then the slipping work curve produced under different work conditions;
③Based on the heat transfer theory, boundary conditions for thermal analysis of clutch friction are acquired. The finite element models of clutch friction disk and the pressure plate are established. Temperature rising of them is acquired and their transient temperature field distribution is obtained using ANSYS software;
④Through the front studies temperature rising of pairs, we determine the influence factors of temperature rise of clutch friction pairs. It is useful for reducing the temperature rising, carrying capacity and enhancing the service life of dry type structure of dual clutch design and cooling systems and equipment design;
⑤Temperature-rise and wear testing system is studied.The dry clutch simulation test system is designed.The basic structure of test bench and the testing process are established.
引文
[1]庄继德.汽车电子控制系统工程[M].北京:北京理工大学出版社,1998.
[2]冯巍. DCT起步与换档特性的仿真方法研究[D].吉林:吉林大学,2007.
[3]葛安林.自动变速器综述(一)[J].汽车技术,2001,(5),1-3.
[4] Y.Zhang , X.Chen. Dynamic Modeling and Simulation of a Dual-clutch Automated Lay-shaft Transmission[J]. Journal of University of Michigan-Dearborn,2004.
[5] Xubin Song,Jason Liu and Daniel Smedley. Simulation Study of Dual Clutch Transmission for Medium Duty Truck Applications[J]. SAE,2005,(1):3590.
[6] Bernd Matthes. Dual Clutch Transmissions Lessons Learned and Future Potential[J]. SAE,2005,(1):1021.
[7] J.C.Wheals , C.Crewe , M.Ramsbottom, S.Rook and M.Westby. Automated Manual Transmissions-A European Survey and Proposed Quality Shift Metrics[J]. SAE,2002,(1):0929.
[8] Kevin Jost. A Different Automatic[J]. Automotive Engineering International,2003,(7):32-36.
[9] Volkswagen AG,DSG Press Release[J]. Wolfsburg Germany,2002,11.
[10] Reinhard Berger,Rolf Meinhard,Carsten Bünder. The Parallel Shift Gearbox PSG-Twin Clutch Gearbox with Dry Clutches. 7th LuK Symposium, 2002,4,11./12. .
[11]离合器:干式还是湿式[J].汽车工艺与材料,2007,(04):63-64.
[12]操剑锋.湿式双离合器自动变速器仿真技术研究论文[D].吉林:吉林大学,2007.
[13]朱攀.车辆制动摩擦材料关键特性的研究及检测方法[D].武汉:武汉理工大学,2006.
[14]关庆丰,李光玉,李晓宇.碳纤维对增强的摩阻材料的摩擦磨损性能的影响[J].吉林工业大学学报,1997,27(3):73-76.
[15]贾贤.汽车摩擦材料增强纤维研究综述[J].汽车技术,1994,(1):114.
[16]刘震之.汽车摩擦材料增强纤维研究综述[J].汽车技术,1999,(1):19.
[17]刘长生.汽车摩擦学[M].合肥:安徽科学技术出版社,1998,108-109.
[18]张剑锋,周志芳著.摩擦磨损与抗磨技术[M].天津:天津科技翻译出版公司,1993.
[19] M. Goetz,M. C. Levesley and D. A. Crolla. Integrated Power train Control of Gearshifts on Twin Clutch Transmissions[J]. SAE, 2004.
[20]韩凤麟,马福康,曹勇家.中国材料工程大典(14卷)[M] .北京:化学工业出版社,2005,8,919.
[21]张明韶,刘勇兵,杨晓红.车用摩擦材料的摩擦学研究进展.摩擦学学报,1999,19(4):379-384.
[22] Jack M. G,Tsang P.H.S and Rhee S.K. Wear debris compaction and friction film formation of polymer composites. Wear of Materials,ASME,New York,1989.
[23] Rhee S.K,Jack M.G,Tsang P.H.S. The role of friction film in friction, wear and noise of automotive brakes. Wear,1991,146(1):89-97.
[24] Rhee S.K. Wear equation for polymers sliding against metal surfaces. Wear,1970,(16):431-445.
[25]徐石安,江发潮.汽车离合器[M].北京:清华大学出版社,2005.
[26]雷雨龙,葛安林等.离合器起步过程的控制策略[J].汽车工程,2000,22(4):266-269.
[27] Richard G. Reed,Jr., Oak,Jeffrey P Cherry, Troy. Method of Controlling a Transmission Having a Dual Clutch System. US 6463821B1,2002-10-15.
[28]过学迅.汽车自动变速器[M].机械工业出版社,1999.
[29]胡建军.汽车无级变速传动系统建模、仿真及其匹配控制策略研究[D].重庆:重庆大学,2001.
[30]张慎良等.车用汽油机动态性能研究[J].内燃机工程,1988(1).
[31]杨昭.双离合器自动变速器动力学建模及仿真研究[D].吉林:吉林大学,2007.
[32]王玉海,宋健,李兴坤.离合器动态过程建模与仿真[J].公路交通科技,2004,10(121), 110.
[33]张朝晖. ANSYS热分析教程与实例解析[M].北京:中国铁道出版社,2007,2.
[34]姚仲鹏,王瑞君,张习军编.传热学[M].北京:北京理工大学出版社,1995.
[35]杨鹏飞,鼓式制动器温度场的数值模拟研究[D].长安:长安大学,2004,5.
[36] Bark L S. Chemical changes in asbestos base friction material during performance. Wear,1995,(34):345-348.
[37]姚仲鹏,王新国.车辆冷却传热[M].北京:北京理工大学出版社,2001,6.
[38]孙东野.湿式多片制动器破坏机理与设计方法研究[D].重庆:重庆大学,1996.
[39]张永振等.材料的干摩擦学[M].北京:科学出版社,2007.
[40] BAEBER J R. The conduction of heat from sliding solids. Int J Heat﹠Mass Transfer,1970,13(5):857-869.
[41] ABDEL-AALHA. On the distribution of friction-induced heat in the dry sliding of metallic solid pairs[J]. International Communications in Heat and Mass Transfer,1997,24(7):93-104.
[42] Bhushan B. Temperature and Friction of sliding surfaces. Massachusetts:IT,Cambridge,1971.
[43]赵镇南.传热学[M].高等教育出版社,2002.
[44] L.鲁道夫.汽车制动系统的分析与设计[M].北京:机械工业出版社,1985,12.
[45] Yuan Mao Huang,Shi-Han Chen. Analytical Study of Design Parameters on Cooling Performance of a Brake Disk. SAE,2006,(1):0692.
[46] Mills,A. F.,1999,Heat Transfer, 2nd edition,Prentice Hall,Inc.,p362-365,ISBN: 0139476245.
[47]李亮,宋建,李永,郭振宇.制动器热分析的快速有限元仿真模型研究[J].系统仿真学报,2005,12(17):2869-2877.
[48]霍晓强,刘安.湿式换挡离合器摩擦副瞬态温度场的仿真研究[J].工程机械,2006,3(37):23-28.
[49] H He,K Okubo,T Fuji,Y Takemoto and Y Doman. Thermal Deformation of Pressure Plates for Manual Clutches[J]. SAE,2005,(1):1784.
[50]胡家秀.简明机械零件设计实用手册[M].北京:机械工业出版社,2002.
[51]朱茂桃,张铁山,夏长高,高翔.离合器压盘表面工作温度变化规律的测定[J].江苏理工大学学报,1996,2(17):32—37.
[52]李立斌.综合性能试验台的设计与计算机仿真[D].长沙:湖南大学,2004.
[53]汽车工程手册·实验篇[M].北京:人民交通出版社,2001,151-154.
[54]汽车工程手册·设计篇[M].北京:人民交通出版社,2001,151-154.
[2]冯巍. DCT起步与换档特性的仿真方法研究[D].吉林:吉林大学,2007.
[3]葛安林.自动变速器综述(一)[J].汽车技术,2001,(5),1-3.
[4] Y.Zhang , X.Chen. Dynamic Modeling and Simulation of a Dual-clutch Automated Lay-shaft Transmission[J]. Journal of University of Michigan-Dearborn,2004.
[5] Xubin Song,Jason Liu and Daniel Smedley. Simulation Study of Dual Clutch Transmission for Medium Duty Truck Applications[J]. SAE,2005,(1):3590.
[6] Bernd Matthes. Dual Clutch Transmissions Lessons Learned and Future Potential[J]. SAE,2005,(1):1021.
[7] J.C.Wheals , C.Crewe , M.Ramsbottom, S.Rook and M.Westby. Automated Manual Transmissions-A European Survey and Proposed Quality Shift Metrics[J]. SAE,2002,(1):0929.
[8] Kevin Jost. A Different Automatic[J]. Automotive Engineering International,2003,(7):32-36.
[9] Volkswagen AG,DSG Press Release[J]. Wolfsburg Germany,2002,11.
[10] Reinhard Berger,Rolf Meinhard,Carsten Bünder. The Parallel Shift Gearbox PSG-Twin Clutch Gearbox with Dry Clutches. 7th LuK Symposium, 2002,4,11./12. .
[11]离合器:干式还是湿式[J].汽车工艺与材料,2007,(04):63-64.
[12]操剑锋.湿式双离合器自动变速器仿真技术研究论文[D].吉林:吉林大学,2007.
[13]朱攀.车辆制动摩擦材料关键特性的研究及检测方法[D].武汉:武汉理工大学,2006.
[14]关庆丰,李光玉,李晓宇.碳纤维对增强的摩阻材料的摩擦磨损性能的影响[J].吉林工业大学学报,1997,27(3):73-76.
[15]贾贤.汽车摩擦材料增强纤维研究综述[J].汽车技术,1994,(1):114.
[16]刘震之.汽车摩擦材料增强纤维研究综述[J].汽车技术,1999,(1):19.
[17]刘长生.汽车摩擦学[M].合肥:安徽科学技术出版社,1998,108-109.
[18]张剑锋,周志芳著.摩擦磨损与抗磨技术[M].天津:天津科技翻译出版公司,1993.
[19] M. Goetz,M. C. Levesley and D. A. Crolla. Integrated Power train Control of Gearshifts on Twin Clutch Transmissions[J]. SAE, 2004.
[20]韩凤麟,马福康,曹勇家.中国材料工程大典(14卷)[M] .北京:化学工业出版社,2005,8,919.
[21]张明韶,刘勇兵,杨晓红.车用摩擦材料的摩擦学研究进展.摩擦学学报,1999,19(4):379-384.
[22] Jack M. G,Tsang P.H.S and Rhee S.K. Wear debris compaction and friction film formation of polymer composites. Wear of Materials,ASME,New York,1989.
[23] Rhee S.K,Jack M.G,Tsang P.H.S. The role of friction film in friction, wear and noise of automotive brakes. Wear,1991,146(1):89-97.
[24] Rhee S.K. Wear equation for polymers sliding against metal surfaces. Wear,1970,(16):431-445.
[25]徐石安,江发潮.汽车离合器[M].北京:清华大学出版社,2005.
[26]雷雨龙,葛安林等.离合器起步过程的控制策略[J].汽车工程,2000,22(4):266-269.
[27] Richard G. Reed,Jr., Oak,Jeffrey P Cherry, Troy. Method of Controlling a Transmission Having a Dual Clutch System. US 6463821B1,2002-10-15.
[28]过学迅.汽车自动变速器[M].机械工业出版社,1999.
[29]胡建军.汽车无级变速传动系统建模、仿真及其匹配控制策略研究[D].重庆:重庆大学,2001.
[30]张慎良等.车用汽油机动态性能研究[J].内燃机工程,1988(1).
[31]杨昭.双离合器自动变速器动力学建模及仿真研究[D].吉林:吉林大学,2007.
[32]王玉海,宋健,李兴坤.离合器动态过程建模与仿真[J].公路交通科技,2004,10(121), 110.
[33]张朝晖. ANSYS热分析教程与实例解析[M].北京:中国铁道出版社,2007,2.
[34]姚仲鹏,王瑞君,张习军编.传热学[M].北京:北京理工大学出版社,1995.
[35]杨鹏飞,鼓式制动器温度场的数值模拟研究[D].长安:长安大学,2004,5.
[36] Bark L S. Chemical changes in asbestos base friction material during performance. Wear,1995,(34):345-348.
[37]姚仲鹏,王新国.车辆冷却传热[M].北京:北京理工大学出版社,2001,6.
[38]孙东野.湿式多片制动器破坏机理与设计方法研究[D].重庆:重庆大学,1996.
[39]张永振等.材料的干摩擦学[M].北京:科学出版社,2007.
[40] BAEBER J R. The conduction of heat from sliding solids. Int J Heat﹠Mass Transfer,1970,13(5):857-869.
[41] ABDEL-AALHA. On the distribution of friction-induced heat in the dry sliding of metallic solid pairs[J]. International Communications in Heat and Mass Transfer,1997,24(7):93-104.
[42] Bhushan B. Temperature and Friction of sliding surfaces. Massachusetts:IT,Cambridge,1971.
[43]赵镇南.传热学[M].高等教育出版社,2002.
[44] L.鲁道夫.汽车制动系统的分析与设计[M].北京:机械工业出版社,1985,12.
[45] Yuan Mao Huang,Shi-Han Chen. Analytical Study of Design Parameters on Cooling Performance of a Brake Disk. SAE,2006,(1):0692.
[46] Mills,A. F.,1999,Heat Transfer, 2nd edition,Prentice Hall,Inc.,p362-365,ISBN: 0139476245.
[47]李亮,宋建,李永,郭振宇.制动器热分析的快速有限元仿真模型研究[J].系统仿真学报,2005,12(17):2869-2877.
[48]霍晓强,刘安.湿式换挡离合器摩擦副瞬态温度场的仿真研究[J].工程机械,2006,3(37):23-28.
[49] H He,K Okubo,T Fuji,Y Takemoto and Y Doman. Thermal Deformation of Pressure Plates for Manual Clutches[J]. SAE,2005,(1):1784.
[50]胡家秀.简明机械零件设计实用手册[M].北京:机械工业出版社,2002.
[51]朱茂桃,张铁山,夏长高,高翔.离合器压盘表面工作温度变化规律的测定[J].江苏理工大学学报,1996,2(17):32—37.
[52]李立斌.综合性能试验台的设计与计算机仿真[D].长沙:湖南大学,2004.
[53]汽车工程手册·实验篇[M].北京:人民交通出版社,2001,151-154.
[54]汽车工程手册·设计篇[M].北京:人民交通出版社,2001,151-154.
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