Finite differences software for the numeric analysis of a non-destructive electromagnetic testing system
In this paper, theoretical bases for the development of a software for electromagnetic effects simulation based on the approximation method of finite differences using Scilab are presented. A methodology for programming the algorithm is discussed and a simulation test is conducted in order to validate it, which consists of a coil with a ferromagnetic core. Finally, this software is used in studies related to magnetic flux leakage by a simulation of a system for the measurement of magnetic flux density in plates with different defects, which include both 2D and 3D and defects with orientation of 45 degrees.
Contribuciones al método de las diferencias finitas para la resolución de las ecuaciones de Maxwell en el dominio del tiempo
En la memoria, junto a una completa revision bibliografica, se hace un estudio de los esquemas en diferencias finitas para la resolucion de las ecuaciones de maxwell en el dominio del tiempo; abordandose los conceptos de consistencia, convergencia y estabilidad en tres dimensiones.Tambien se estudia el metodo de conformacion para aproximar mejor la geometria del objeto dispersor, evitando asi falsas soluciones numericas. Se proponen modificaciones para disminuir las inestabilidades que surgen en el proceso de solucion escalonado en el tiempo. Los resultados obtenidos se validan con resultados teoricos y experimentales en dos y tres dimensiones.
A Finite Element Procedure for Dynamic Micromagnetic Computations
This paper presents a 3-D dynamic micromagnetic numerical scheme, based on the decoupling of the effective field evaluation from the treatment of the Landau-Lifshitz equation. The weak formulation of the effective field expression is spatially discretized through a nodal finite element approach. The micromagnetic equation is locally computed, performing the time integration with a finite difference scheme, based on midpoint rule and able to preserve the magnetization nonconvex constraint. Different techniques are compared for the evaluation of the magnetostatic field, such as finite element/boundary element method, standard finite element approach with first-order asymptotic boundary conditions, and Green integral formulation.