In order to analyze the energy consumption of wheel loader during working process, a three-dimensional（3D） model of wheel loader is established by Pro/E software, and it is imported into the software SimulationX tob...In order to analyze the energy consumption of wheel loader during working process, a three-dimensional（3D） model of wheel loader is established by Pro/E software, and it is imported into the software SimulationX tobuild the kinetic model of the whole wheel loader. Meanwhile, the simulation model of hydraulic system is builtby the same software. By integrating the simulation model of hydraulic system with the kinetic model, the co-sim-ulation model of wheel loader could be achieved. The precision of co-simulation model of the working device isverified through the comparison between simulation results and test results. The testing results show that, undernegative loading condition, the energy loss in multi-way valve accounts for about 52%. The important energy lossin loader＇s working hydraulic system using constant displacement pump is the large throttling loss of multi-wayvalves. This study provides a reference for designing of a more energy-efficient hydaulic system of wheel loader.展开更多
针对重型工程车轮在径向载荷工况下有限元分析(Finite Element Analysis,FEA)的不准确问题,基于车轮-轮胎接触压力测试结果,构建了一种新的仿真分析模型。首先,测试车轮仅在充气压力工况下的应力数据,并以4阶高斯函数拟合充气压力加载模...针对重型工程车轮在径向载荷工况下有限元分析(Finite Element Analysis,FEA)的不准确问题,基于车轮-轮胎接触压力测试结果,构建了一种新的仿真分析模型。首先,测试车轮仅在充气压力工况下的应力数据,并以4阶高斯函数拟合充气压力加载模型;然后,测试车轮在充气压力和径向载荷共同作用下的应力数据,消去充气压力的影响,并以4阶傅里叶函数和4阶正弦和函数分别拟合径向载荷周向加载模型和轴向加载模型;最后,通过Ansys软件仿真验证加载模型。结果显示,与实测数据相比,关键校核点的计算误差仅为1.943%。此外,应力分布也显示出高度的一致性,证明了径向接触压力分布模型的准确性和可靠性较高。展开更多
Operation safety and stability of the train mainly depend on the interaction between the wheel and rail.Knowledge of wheel/rail contact force is important for vehicle control systems that aim to enhance vehicle stabil...Operation safety and stability of the train mainly depend on the interaction between the wheel and rail.Knowledge of wheel/rail contact force is important for vehicle control systems that aim to enhance vehicle stability and passenger safety.Since wheel/rail contact forces of high-speed train are very difficult to measure directly,a new estimation process for wheel/rail contact forces was introduced in this work.Based on the state space equation,dynamic programming methods and the Bellman principle of optimality,the main theoretical derivation of the inversion mathematical model was given.The new method overcomes the weakness of large fluctuations which exist in current inverse techniques.High-speed vehicle was chosen as the research object,accelerations of axle box as input conditions,10 degrees of freedom vertical vibration model and 17 degrees of freedom lateral vibration model were established,respectively.Under 250 km/h,the vertical and lateral wheel/rail forces were identified.From the time domain and frequency domain,the comparison of the results between inverse and SIMPACK models were given.The results show that the inverse mathematical model has high precision for inversing the wheel/rail contact forces of an operation high-speed vehicle.展开更多
文摘In order to analyze the energy consumption of wheel loader during working process, a three-dimensional（3D） model of wheel loader is established by Pro/E software, and it is imported into the software SimulationX tobuild the kinetic model of the whole wheel loader. Meanwhile, the simulation model of hydraulic system is builtby the same software. By integrating the simulation model of hydraulic system with the kinetic model, the co-sim-ulation model of wheel loader could be achieved. The precision of co-simulation model of the working device isverified through the comparison between simulation results and test results. The testing results show that, undernegative loading condition, the energy loss in multi-way valve accounts for about 52%. The important energy lossin loader＇s working hydraulic system using constant displacement pump is the large throttling loss of multi-wayvalves. This study provides a reference for designing of a more energy-efficient hydaulic system of wheel loader.
文摘针对重型工程车轮在径向载荷工况下有限元分析(Finite Element Analysis,FEA)的不准确问题,基于车轮-轮胎接触压力测试结果,构建了一种新的仿真分析模型。首先,测试车轮仅在充气压力工况下的应力数据,并以4阶高斯函数拟合充气压力加载模型;然后,测试车轮在充气压力和径向载荷共同作用下的应力数据,消去充气压力的影响,并以4阶傅里叶函数和4阶正弦和函数分别拟合径向载荷周向加载模型和轴向加载模型;最后,通过Ansys软件仿真验证加载模型。结果显示,与实测数据相比,关键校核点的计算误差仅为1.943%。此外,应力分布也显示出高度的一致性,证明了径向接触压力分布模型的准确性和可靠性较高。
基金Project(2009BAG12A04-A11)supported by the National Key Technology R&D Program in the"11-th Five-year Plan"of ChinaProjects(51275432,51005190)supported by the National Natural Science Foundation of ChinaProject(SWJTU09ZT23)supported by University Doctor Academics Particularly Science Research Fund,China
文摘Operation safety and stability of the train mainly depend on the interaction between the wheel and rail.Knowledge of wheel/rail contact force is important for vehicle control systems that aim to enhance vehicle stability and passenger safety.Since wheel/rail contact forces of high-speed train are very difficult to measure directly,a new estimation process for wheel/rail contact forces was introduced in this work.Based on the state space equation,dynamic programming methods and the Bellman principle of optimality,the main theoretical derivation of the inversion mathematical model was given.The new method overcomes the weakness of large fluctuations which exist in current inverse techniques.High-speed vehicle was chosen as the research object,accelerations of axle box as input conditions,10 degrees of freedom vertical vibration model and 17 degrees of freedom lateral vibration model were established,respectively.Under 250 km/h,the vertical and lateral wheel/rail forces were identified.From the time domain and frequency domain,the comparison of the results between inverse and SIMPACK models were given.The results show that the inverse mathematical model has high precision for inversing the wheel/rail contact forces of an operation high-speed vehicle.
