Mechanical Modeling And Numerical Research On The Vehicle Collision Test With Hydraulic Buffer

The sled crash test is an important test method for passive safety performance of automobiles and is widely used in the development of automotive products.At present,the most commonly used one is the sled crash test based on the hydraulic buffer device,but the working process of the porous type hydraulic buffer is affected by many factors,and the theoretical research on the collision process is not extensive and deep enough.In this thesis,the hydraulic buffer sled crash test device is taken as the research object.The porous type hydraulic buffer in the sled collision process is theoretically calculated.The piston assembly,the hydraulic cylinder assembly and the damping hole are designed,and the performance of the progressive hydraulic buffer is obtained.Then,through the study on the O-ring seal of the hydraulic buffer piston of the sled crash test system,the auto-correlation function is used to simulate the micro-surface,and the fluid dynamic pressure lubrication process in the hydraulic buffer process is numerically studied.With an example,the lubrication performance of the seal under different working conditions is calculated.The collision test of the porous type hydraulic buffering sled is studied.The mechanics and fluid mechanics theory are applied to analyze the mechanical process of the collision process.According to the principle of energy conservation,the mechanical model of the sled collision process is constructed and a discrete numerical solution method is proposed for numerically solving the model.The parameters such as the sled quality,the initial collision velocity and the diameter of the damping hole on the performance of the collision process are analyzed in detail.A series of specific curves are obtained,and the relevant conclusions are obtained.The research results in this thesis can provide useful theoretical references for the design of porous type hydraulic buffer and the further research and application of vehicle collision test with hydraulic buffer.