铁路道碴瞬态电磁散射特性分析

引用离散随机媒质结构来模拟铁路道碴的分布情况，采用在ＦＤＴＤ法的差分网格中进行随机填充来实现铁路道碴的计算模拟模型，并求解其瞬态电磁散射场。通过对该散射场的处理，提取出道碴的非相关散射场，然后再对该非相关场进行分析，得出了可描述道碴分布状况的电磁参量。数值分析结果显示，该参量与道碴空隙率之间在一定范围内具有指数关系。这表明，用电磁方法来探测铁路道碴的空隙率是可能的。

Analysis of Transient Electromagnetic Scattering for Railway Ballast

A discrete model for random media is employed to simulate the distribution of railway ballast. The calculation simulation model for railway ballast is built by random filling in the meshes of FDTD method, and the intensities of the transient electromagnetic scattering field are calculated. Then the incoherent scattering field is calculated and analyzed to obtain the electromagnetic parameters for the distribution of the railway ballast. The numerical analysis result shows that there exists an exponential function relationship in a certain range between the obtained parameters and the porosity of railway ballast. Therefore, it can be concluded that applying the electromagnetic technology to detect the porosity of railway ballast is possible.