重载列车牵引制动系统动力学研究
摘要
重载运输是除高速以外,铁路现代化的又一个标志。发展铁路重载运输得到世界上越来越多国家的重视,已被国际上公认为铁路货运发展的方向。20世纪80年代,我国修建了第一条电气化重载铁路—大秦线,在此之后重载运输在我国得到了快速发展。
随着重载列车编组的扩大、列车重量增大,长度增加,轴重增大和运营速度的提高,列车运行中的牵引力及制动力加大,制动波传递时间加长,各种与牵引和制动特性相关的安全事故频发,已经严重影响重载列车的安全运行,因而对长大重载列车牵引和制动动力学进行系统的研究,对于确保长大重载列车运输系统的行车安全具有非常重大的意义。而目前对牵引和制动动力学的研究都集中在纵向动力学方面,没有对其垂向和横向动力学的研究,所以很有必要展开对牵引和制动纵向、横向和垂向综合考虑的系统动力学研究,这也正是本文的研究目的。此外,目前列车动力学仿真中普遍采用等波速传播的空气制动特性,没有考虑空气制动的动态制动特性,因而会造成较大的误差。
针对传统列车动力学研究中出现的自由度众多,难于计算处理等局限以及动力学仿真中采用等波速制动特性带来的误差,本文运用基于循环变量的模块化建模及数值求解方法结合基于空气流动理论的空气制动仿真系统对重载列车牵引和制动动力学做了较为系统的研究,主要从以下几个方面进行分析：
(1)重载列车牵引和制动对动力学影响的基本原理；
(2)重载列车在直线、曲线和坡道上牵引、惰行和制动时的动力学性能；
(3)分析比较在牵引和制动工况下机车不同组合编组时纵向冲动的差异,确定机车最佳组合方式；
(4)分析比较在牵引和制动工况下空重车混合编组时空车编组在不同位置时动力学性能,确定空车最佳编组位置。
通过对重载列车牵引和制动系统动力学的全面分析,初步揭示了其与线路、编组和操纵方式之间的相互作用关系,反映了重载列车运行过程中的动态运行行为。
Heavy haul transportation is another mark of railway modernization in addition to high-speed train. The development of railway heavy haul transportation have been paid more attention by more and more countries, and been internationally recognized as the direction of the rail freight. In 1980s, Datong-Qinhuangdao railway the first electrified heavy haul rail of China has been built, then, heavy haul transportation has developed rapidly.
However, with the increase of train marshalling and hauling weight, and also a longer in length, and more heavy of axle load, and higher speed, the traction force and braking force of heavy haul train is increased, and the propagation time of brake wave is longer, various accidents related to traction and braking characteristics occuered, have seriously affected the safty of the heavy haul trains. Therefore, take a systematic comprehensive study of the dynamic performance on traction and braking of heavy haul train, has a great significance for ensuring safety of the heavy haul train transportation system.
Additionly, the current dynamics study of traction and brake are concentrated on the longitudinal dynamics, and have no research on its vertical and lateral dynamics, so, it is necessary to start the study of traction and braking system dynamics which including the vertical, horizontal and vertical dynamics, and this is just the purpose of this paper. What's more, the commonly velocity spread air brake characteristics was widely used in current train dynamic simulation, without considering the dynamic braking characteristics of the air brake, which will result in large errors.
Then, according to the limitation of traditional research on dynamics of train, and the errors caused by the commonly velocity spread air braking characteristics, a new method named Modular Modeling Method Based on Circular-Variable and combined with the air brake train simulation system based on the air flow theory have been used in this thesis to make a systematic study on traction and brake dynamics of heavy haul train. The detailed aspects are as follows:
(1) The basic principles of traction and braking effect on dynamics of heavy haul train;
(2) The dynamic performance while heavy haul train traction and braking on straight lines, curves and ramps railway road condition;
(3) Comparative and analysis the longitudinal impulse difference between different locomotive marshalling combinations when traction and braking, to determine the best locomotive marshalling;
(4) Comparative and analysis the dynamic performance while empty vehicle marshalling in different location of the train while traction and braking operating condition, to determine the best marshalling positions for empty vehicles.
Though the comprehensive analysis of traction and braking system dynamics of heavy haul train, it is easy for us to know the relationship between train dynamics and railway line, formation and operation of train. Furthermore, the analysis results show the dynamic behavior of heavy haul train.
随着重载列车编组的扩大、列车重量增大,长度增加,轴重增大和运营速度的提高,列车运行中的牵引力及制动力加大,制动波传递时间加长,各种与牵引和制动特性相关的安全事故频发,已经严重影响重载列车的安全运行,因而对长大重载列车牵引和制动动力学进行系统的研究,对于确保长大重载列车运输系统的行车安全具有非常重大的意义。而目前对牵引和制动动力学的研究都集中在纵向动力学方面,没有对其垂向和横向动力学的研究,所以很有必要展开对牵引和制动纵向、横向和垂向综合考虑的系统动力学研究,这也正是本文的研究目的。此外,目前列车动力学仿真中普遍采用等波速传播的空气制动特性,没有考虑空气制动的动态制动特性,因而会造成较大的误差。
针对传统列车动力学研究中出现的自由度众多,难于计算处理等局限以及动力学仿真中采用等波速制动特性带来的误差,本文运用基于循环变量的模块化建模及数值求解方法结合基于空气流动理论的空气制动仿真系统对重载列车牵引和制动动力学做了较为系统的研究,主要从以下几个方面进行分析：
(1)重载列车牵引和制动对动力学影响的基本原理；
(2)重载列车在直线、曲线和坡道上牵引、惰行和制动时的动力学性能；
(3)分析比较在牵引和制动工况下机车不同组合编组时纵向冲动的差异,确定机车最佳组合方式；
(4)分析比较在牵引和制动工况下空重车混合编组时空车编组在不同位置时动力学性能,确定空车最佳编组位置。
通过对重载列车牵引和制动系统动力学的全面分析,初步揭示了其与线路、编组和操纵方式之间的相互作用关系,反映了重载列车运行过程中的动态运行行为。
Heavy haul transportation is another mark of railway modernization in addition to high-speed train. The development of railway heavy haul transportation have been paid more attention by more and more countries, and been internationally recognized as the direction of the rail freight. In 1980s, Datong-Qinhuangdao railway the first electrified heavy haul rail of China has been built, then, heavy haul transportation has developed rapidly.
However, with the increase of train marshalling and hauling weight, and also a longer in length, and more heavy of axle load, and higher speed, the traction force and braking force of heavy haul train is increased, and the propagation time of brake wave is longer, various accidents related to traction and braking characteristics occuered, have seriously affected the safty of the heavy haul trains. Therefore, take a systematic comprehensive study of the dynamic performance on traction and braking of heavy haul train, has a great significance for ensuring safety of the heavy haul train transportation system.
Additionly, the current dynamics study of traction and brake are concentrated on the longitudinal dynamics, and have no research on its vertical and lateral dynamics, so, it is necessary to start the study of traction and braking system dynamics which including the vertical, horizontal and vertical dynamics, and this is just the purpose of this paper. What's more, the commonly velocity spread air brake characteristics was widely used in current train dynamic simulation, without considering the dynamic braking characteristics of the air brake, which will result in large errors.
Then, according to the limitation of traditional research on dynamics of train, and the errors caused by the commonly velocity spread air braking characteristics, a new method named Modular Modeling Method Based on Circular-Variable and combined with the air brake train simulation system based on the air flow theory have been used in this thesis to make a systematic study on traction and brake dynamics of heavy haul train. The detailed aspects are as follows:
(1) The basic principles of traction and braking effect on dynamics of heavy haul train;
(2) The dynamic performance while heavy haul train traction and braking on straight lines, curves and ramps railway road condition;
(3) Comparative and analysis the longitudinal impulse difference between different locomotive marshalling combinations when traction and braking, to determine the best locomotive marshalling;
(4) Comparative and analysis the dynamic performance while empty vehicle marshalling in different location of the train while traction and braking operating condition, to determine the best marshalling positions for empty vehicles.
Though the comprehensive analysis of traction and braking system dynamics of heavy haul train, it is easy for us to know the relationship between train dynamics and railway line, formation and operation of train. Furthermore, the analysis results show the dynamic behavior of heavy haul train.
引文
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[15]Hiroshi Fujimoto, Masayuki Miyamoto. The vibration analysis of the trail car in a train [J]. QR of RTRI,1989,30(1):42-47.
[16]Shiro Koynagi. A method of lateral vibration on analysis of the tail vehicle of a train [J]. QR of RTRI,1990,31(1):2-6.
[17]Masayuki Miyamoto, Hiroshi Fujimoto. Vertical riding comfort of articulated railway vehicle-A new method for the dynamic analysis of intermediate vehicles in a long train [J]. QR of RTRI,1986,27(3):88-93.
[18]Hajime Wakui, Nobuyuki Matsumoto. A study on dynamic interaction analysis for railway vehicles and structures-mechanical model and practical analysis method [J]. QR of RTRI,1994,35(2):96-104.
[19]沈利人译V.K.Garg, Rao V.Dukkipati.铁道车辆系统动力学[M].成都：西南交通大学出版社,1998.
[20]王启铭.大秦线2万t重载组合列车试验研究[J].铁道机车车辆,2008,28(6)：8-10,46.
[21]耿志修,李学峰,张波.大秦线重载列车运行仿真计算研究[J].中国铁道科学,2008,29(2)：88-93.
[22]常崇义,王成国,马大炜,张波.2万t组合列车纵向力计算研究[J].铁道学报,2006,28(2)：89-94.
[23]马大炜.重载列车及其试验研究—我国重载列车的实验研究(上,中,下)[J].铁道车辆,1999,37(4,5,6).
[24]程海涛,钱立新.长大货物列车制动时纵向动力学模型及求解方法初探[J].铁道车辆,1998,36(11)：10-12.
[25]赵鑫,王成国,马大炜.机车无线同步控制技术对2万t重载组合列车纵向力的影响.中国铁道科学.2008,29(3)：78-83
[26]Roberson Re. and S chwertassek R. Dynamics of Multi-body Systems [M]. Berlin:Spring-Verlag,1998.
[27]Wittenburg J.多刚体系统动力学[M].北京：航空航天大学出版社,1986.
[28]袁士杰,吕哲勤.多刚体系统动力学[M].北京：北京理工大学出版社,1992.
[29]洪嘉振.计算多体系统动力学[M].北京：高等教育出版社,1992.
[30]贺启庸,倪纯双,王卫东.多体系统动力学与车辆动力学[J].铁道车辆,1995,33(1)：38-42.
[31]Weihua Zhang, Maoru Chi, Jing Zeng. A New simulation method for the train dynamics:8th international Heave Haul Conference, Rio de Janeiro, June, 2005 [C]. Rio de Janriro:Heavy Haul Association,2005:773-778.
[32]池茂儒,张卫华,曾京,戴焕云,邬平波.长大列车动力学建模的一种新方法[J].铁道车辆,2007,45(3)：1-4.
[33]翟婉明.车辆—轨道耦合动力学[M].北京：中国铁道出版社,2002.
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