The Response of In-loop Transient Electromagnetic Configuration

Abstract

For the aim to assess the large loop transient electromagnetic method (TEM), an important method in engineering exploration, we study the distribution of vertical and horizontal magnetic component by calculating the 1-D response corresponding to in-loop and out-loop field point. A new algorithm for Dual Bessel integral has been developed. We divided the integral range \( (0,\infty ) \) into \( (0,\lambda_{0} ] \) and \( [\lambda_{0} ,\infty ) \). In the integral range of \( (0,\lambda_{0} ] \), based on the derivative relationship of Bessel integral, transforming the integral into the form of easily calculation. In the range of integral of \( [\lambda_{0} ,\infty ) \), Linear sine and cosine transformation algorithm can be used for the computation. We design models for numerical simulation and give the result. Based on the results, we draw a conclusion that vertical magnetic field component can be surveyed in the range of 50% inside of the loop and horizontal magnetic field component is so smaller than vertical component that it can not be well surveyed inside large loop.