Yin H.,Hunan University |
Wen G.,Hunan University |
Hou S.,Hunan University |
Chen K.,Qingdao Sifang Rolling Stock Research Institute Co.
Materials and Design | Year: 2011
Honeycomb-filled tubes have recently gained attention for their enhanced energy absorption capacity. This paper firstly investigates the energy absorption characteristics of honeycomb-filled single and bitubular polygonal tubes (HSBPT) by nonlinear finite element analysis through LS-DYNA. By employing a six-level judgement method, we find that both of the honeycomb-filled single and honeycomb-filled bitubular tubes with enneagonal configuration have very excellent energy absorption characteristics among the considered cases. Next, the HSBPTs with enneagonal configuration are optimized by adopting multiobjective particle swarm optimization (MOPSO) algorithm to achieve maximum specific energy absorption (SEA) capacity and minimum peak crushing force (PCF). During the process of multiobjective optimization design (MOD), accurate metamodels of SEA and PCF of the HSBPTs with enneagonal configuration are established to reduce the computational cost of crash simulations by finite element method. Numerical experiments show that the quartic polynomial functions of SEA and PCF are the suitable metamodels for both honeycomb-filled single and bitubular enneagonal tubes. © 2011 Elsevier Ltd. Source
Li X.,Qingdao Sifang Rolling Stock Research Institute Co. |
Li X.,Southwest Jiaotong University |
Li T.,Southwest Jiaotong University
Vehicle System Dynamics | Year: 2013
A new vertical stiffness formula, including a term incorporating the rate of change of the effective area of a belted air spring, is established. Quasi-static vertical stiffness values are calculated using the formula. And four different experimental methods are used to study static and quasi-static vertical stiffness of a belted air spring. Results calculated using the formula are consistent with the experimental data. When the reservoir is small or the load is heavy, we can precisely predict the static and quasi-static extents of vertical stiffness. Differences between theoretical and experimental results are also analysed. We study the influence of geometric parameters on vertical stiffness of a belted air spring. When a reservoir is added to decrease vertical stiffness, we show how to avoid negative stiffness. © 2013 Taylor & Francis. Source
Qingdao Sifang Rolling Stock Research Institute. Ltd. | Date: 2011-06-28
The present invention relates to a comprehensive test bed for vehicle body, which comprises an vehicle body static strength testing apparatus, an vehicle body air tightness testing apparatus, an vehicle coupler strength testing apparatus and an vehicle body mode testing apparatus, wherein the tested vehicle body is provided with a strain foil and a displacement sensor; and the strain foil and the displacement sensor are connected with a data acquisition system. The comprehensive test bed for the vehicle body can perform an vehicle body static strength test on various rail passenger vehicles, an vehicle body steel structure vibration mode test, an vehicle body partial assembly vibration mode test and an vehicle body air tightness test, and can realize strength tests on partial key components of the vehicle body (a transition vehicle coupler, a return vehicle coupler, an vehicle body chassis cross beam, a hoisting structure, an end structure, and the like). The application range of the test bed includes high speed railway train units, urban rail vehicles, railway ordinary vehicles, maglev trains and straddle type single-rail vehicles. The comprehensive test bed for the vehicle body has a wide application range and can automatically carry out various tests on the same test bed, so that the test bed realizes simple and convenient testing process and convenient operation, and saves labor force and labor time.
Qingdao Sifang Rolling Stock Research Institute Co. | Date: 2013-06-10
A transverse adjustment mechanism for a bilateral half-spring type load-carrying head is installed in the casing of the load-carrying head of the lifting unit of a pit type unwheeling machine, fixedly connected with the casing, directly connected to an adjustment unit at the end of the load-carrying head, and installed on a lead screw of the adjustment unit. The transverse adjustment mechanism includes an adjusting nut, an adjusting nut guide, a guiding tube, and a guiding sleeve, a nut mounting plate, a flange plate, a compression spring and a sliding shaft. The invention is currently applied to the transverse adjustment of the no-loading heads and transverse fine adjustment of the load-carrying heads of the CRH train. The structure is reliable and practical, safe, convenient and energy-saving to use and satisfies the demand for the synchronous lifting operation of the entire CRH train of the compatible pit type unwheeling machine.
Qingdao Sifang Rolling Stock Research Institute Co. | Date: 2014-08-27
The patent was disclosed a telescopic mechanism in a telescopic hitch buffer device for use in high speed electric multiple unit (EMU) trains. The telescopic mechanism comprises a compression rod (