Test Method And Experimental Study Of Railway Vehicle Dynamic Characteristics Based On The Bogie Test-bench

It is the inevitable trend for the development of railway vehicles in China, which is high speed and heavy haul. But high Speed and heavy load operation condition will also worsen the running environment of whole vehicle system and components or assemblies, which will be a threat to the running safety. Meanwhile, vibration problem caused by high speed running will become more and more prominent. Railway vehicle is a complexity dynamic system with multidimensional and multi-DOF, and its dynamic performance is the key factor to the running safety and stability. So, study on the dynamic characteristics of whole vehicle and assemblies is of key technologies for the design of high-speed train.Considering the advantages that cannot be interfered from external environment and can realize the simulations of Single motion character or coupling of multiple motion characters of bench tests, it is in good graces of the manufacturer and research institutes. Test bench for dynamic and static parameters of bogie designed by thevehicle transportation Institute of Jilin University is a system which can provide three-dimensional vibration, and also it can realize the vibration simulation with multi-DOF, providing a more effective platform and experiment environment for the dynamic characteristics test. This thesis was based on the test bench, under the condition of multi-period and wide band frequency excitation, emphatically analyzed the suspension dynamic stiffness characteristic of railway vehicle, explored the suspension natural vibration characteristics under independent bogie condition, and the vibration characteristics under full loading condition, which Provided methods and basic theory for the dynamic characteristic test, and is of great significance for the development and manufacture of vehicles.1. This paper presented a deep analysis the realistic background and value of the study, the testing technology of bogie parameters at home and abroad was illustrated in detail. Effect of bogie suspension parameters to resilient vibration of car-bodies was analyzed, and also effect of elastic mode to the running stability was analyzed.2. Research on dynamic parameters of the test bench and the analytic model for bogieA new kind of test bench for dynamic and static parameters of bogie was illustrated and combined with the geometric structure of bench, dynamic and static motion parameters of the bench were analyzed; the frequency characteristic of the acceleration, inertia force, vibrating velocity and vibration power were also analyzed. A multi-factor and nonlinear 39 degrees of freedom rigid-flexible mixed analysis model integrated into tumbler node and traction rod model, which laid a foundation to the test of dynamic and static parameters under Preparation Condition.3. Research on mechanical properties of the test bench based on dynamic excitationTaking the three-dimensional force plate as research object, mechanical properties were investigated under the dynamic excitation. Dynamic and static Linear elastic model of three-dimensional force plate were established, and dynamic output characteristics of the inertia force, displacement were also analyzed deeply. Test models of three-axial dynamic stiffness for the three-dimensional force plate were established, and a thorough inquiry was made for the dynamic stiffness characteristics. This part laid a foundation to test of dynamic stiffness and ensured the accuracy of test results.4. Research on the test method of dynamic stiffness for bogie based on simulated loadBased on the test bench for bogie parameters, dynamic test method for the bogie suspension system stiffness characteristics was put forward via stepping swept sine excitation. A three-axis positioning device of the bogie was developed, which realized the separation of the first and the secondary suspension system. At the same time, measurement and analysis algorithms of suspension dynamic stiffness was put forward from the theoretical point of view under the test bench conditions of translation and rotating incentives, and a single-frequency of multi-cycle loading of suspension stiffness test calculating method was also proposed. Finally, suspension dynamic test models based on the test bench were established, and frequency characteristics curves of the suspension stiffness were solved.5. Analysis of suspension natural vibration characteristics based on semi-vehicle quality simulationAiming at the actual situation of working conditions for independent bogie suspension natural vibration characteristics test, test method based on Semi-car quality simulation was presented, which realized the simulation of bogie curb status load. Modal theory of algorithms and experimental identification method based on displacement was also put forward. Model of test bench-bogie vertical and horizontal vibration based on Simulation of Semi- vehicle were set up, and bogie and car body main vibration frequency and modal had been measured under the vertical and horizontal excitation. The error between test results and the calculated value was smaller, which verified the correctness of the established vertical and lateral dynamics model, which provided technical support and theoretical basis for bogie design and suspension parameters matching.6. Study on vehicle vibration characteristic based under the preparation conditionStudy on the dynamic characteristic under the preparation condition was developed. Under the condition of single-ended bogie excitation, vertical and horizontal linear sine sweep load were exerted to the vehicle, and taking the top of the vehicle body side wall, side wall beams as research object, the vertical and horizontal elastic vibration characteristics of the vehicle body was explored. And taking the traction converter as the main object, coupling vibration rule among traction converter, vertical and horizontal were analyzed, which provided technical support for the design of high-speed rail vehicle dynamic. At the same time, research on vertical attenuation characteristics of the vehicle suspension system was carried out,which provided test support for the vehicle suspension system parameters matching and the improvement of the vehicle running stability.This thesis was based on the test bench for dynamic and static parameters of bogie; mechanical properties were investigated under the dynamic excitation, which ensured the accuracy of test results. Solving method and evaluation method for the dynamic parameters were put forward. Meanwhile, new strategies for the suspension natural vibration characteristics under independent bogie condition and the vibration characteristics under full loading condition were explored, which improved the research of dynamic characteristic for railway vehicles.