Strength Simulation Analysis Of Railway Tank Cars And Study Of Fluid-Solid Coupling Problem

Fluid-solid coupling problem as the interdisciplinary extension of fluid mechanics and solid mechanics of a class of problems,the main content of the study of deformation of the solid in the flow field under the action of various behaviors and deformation of the impact of solid on the flow field.Railroad tank cars are affected by dynamic load during operation,the liquid in the tank shaking,liquid shaking and tank coupling effect,affecting the stability and safety of vehicle operation.In order to improve the stability and safety of railroad tank cars during operation,it is necessary to analyze the liquid shaking problem generated during the process.In this paper,on the basis of nonlinear theory,contact is established between the tank body and the tank belt and matting to improve the quality of simulation analysis.According to the relevant standards to establish the tanker working conditions,strength analysis of the tanker;firstly,the unconstrained free modal analysis of the tanker to get the first tenth order frequency,and the specific order inherent frequency as the fluid shaking excitation frequency in fluid analysis to achieve the harsh conditions,and based on the theory of fluid mechanics,the VOF(Volume of Fluid)model with PISO(Pressure Implicit with Splitting of Operators)algorithm is used for fluid analysis.Secondly,based on the variable gravity method and the use of User Define(UDF)to apply excitation to the fluid domain,the simulation of liquid swaying under different working conditions is realized,and the effect of liquid swaying on the tank body is applied to the tank body in the form of load through the unidirectional data flow coupling of the software,and the strength analysis of the tank body is performed to extract the stresses of the tank car floating and sinking conditions,curve passing conditions,longitudinal impact conditions,and liquid swaying conditions(longitudinal and transverse).The results are used to evaluate the static strength and fatigue strength of the body structure.Finally,for fatigue strength analysis,a nonparametric kernel density estimation method is proposed to verify the distribution match between the measured load spectrum of the line and the simulated load spectrum of the liquid shake,and a kernel regression analysis is also performed on the two types of load spectrum samples,and the results show that the two types of load spectra have the same distribution at 99.7% confidence interval.The accumulated damage at the fatigue assessment point was calculated based on the measured load spectrum of the tanker line and the S-N curve in the IIW standard.