Design And Implementation Of Simulation Platform For Electromagnetic Eddy Current Nondestructive Testing Of RCF On High-speed Rail

The Outline of National Comprehensive Three-dimensional Transportation Network Planning points out that a 200,000 kilometers railway will be built by 2035,which will effectively solve the problem of unbalanced and insufficient transportation development in China.Rail as an important part of railway,it will be damaged due to the harsh working environment,manufacturing error and the repeated rolling of the train.Rail fatigue crack(RFC)is a potential threat for people’s life and health.Therefore,it is necessary to detect RFC.Nowadays,the way of detecting RFC mostly adopted numerical simulation and forward solution of eddy current nondestructive testing are less.Besides,the meshing in the moving and static areas of the rails is a problem when rail is running.The theoretical knowledge of nondestructive testing methods is difficult to understand,which is not convenient for the use and promotion of detect rolling contact fatigue(RCF).In this thesis,the electromagnetic field simulation platform is designed based on the.NET technology,which realizes the forward solution and numerical simulation of RCF.On the one hand,this platform can calculate the electromagnetic induction intensity of RCF by eddy current nondestructive testing when the rail is in different motion situations.On the other hand,it will conveniently judge the RCF by integrating the theoretical calculation and simplifing simulation modeling process.The main research content of this article is divided into three parts:(1)Analytical calculation module of solve RCF’s electromagnetic field distribution by eddy current nondestructive testing.The main content of this module includes analyzing the process of RCF,comparing the differences of RCF’s models and calculating the analytical expressions of different RCF.Matlab mathematical software is adopted to compile the analytical expressions of different RFC into algorithm.Under the.NET framework,this module realises the visual analytical calculation for different RFC’s models by combining with the advantages of C#’s interface design and Matlab’s strong numerical calculation capabilities.(2)2D simulation module of detecting RCF by eddy current nondestructive testing.This module mainly researches the influence of the RFC’s eddy currents distribution by motion induced eddy current(MIEC)detection technology under direct current excitation.The method of parametric modeling is adopted to mesh the 2D RCF,which reduce the professional requirements for operator.The electromagnetic field distribution of 2D RCF models is realised by recording the RFC’s simulation process and modifing the RFC’s simulation script.Considering the principles of human-computer interaction and modular design,sub-interface is composed of geometric modeling,material setting,motion setting,and meshing.What’s more,this platform analyzes the relationship between the change of magnetic induction intensity and the detection of RCF’s depth and width.(3)3D simulation module of detecting RCF by eddy current nondestructive testing.In actual working conditions,RCF is 3D models.This chapter study the difference of 2D numerical simulation and 3D numerical simulation.The database management technology is adopted to store 3D numerical simulation data,which replace the RCF’s numerical simulation process.The data is stored in the database management by the inspection speed and rail parameters,which solves the problem of a large mount of numerical simulation time and the slow speed of store and inquire data.This module has important promotion significance for 3D numerical simulation.