Characteristic Simulation And Applied Research Of Hydraulic Damper In Raily Vehicel

A hydraulic damper is an important component for the bogie in a locomotive. A hydraulic damper can convert vibration and shock caused by the irregularity of rails into thermal energy of hydraulic oil, thus reduces damage to strength and life of a locomotive body. Therefore, safety and comfort of a running train are significantly affected by performances of hydraulic dampers.Recently, with development of railway technology in China, the increased train speed results into more vibration and shock that means high performance hydraulic dampers are required. High performance hydraulic dampers for high speed trains, heavy haul trains and underground trains are almost imported. Due to poor performances, bad reliability and short life, domestic hydraulic dampers are supplied for low speed trains, which have less demand on performances of hydraulic dampers. However, some companies have conducted research and development of high performance hydraulic dampers. This thesis is based upon the hydraulic dampers improving project in CSR Zhuzhou Institute, in order to investigate the numerical optimization design method for hydraulic dampers, flow fields inside hydraulic dampers and especially, inside damper valves were simulated by ANSYS FLUENT, a commercial CFD software.In this thesis, operating principles and processes were analysed. Damper valves were studied based on the damping theory of squeezing film and force conservation and flux conservation, and a mathematic model about hydraulic dampers operating was set up. Then open speeds and open heights of damper valves in hydraulic dampers were calculated in MATLAB. Finally, simulations about hydraulic dampers were carried out in FLUENT. Results show that the indicator diagram with computational data is correlated well with the theoretical indicator diagram. It indicates that feasibility and accuracy of FLUENT simulations for flow field inside hydraulic dampers. Approaches and results in this thesis can provide theoretical foundation and data for structural optimization of hydraulic damper.