AN EXTENDED FINITE ELEMENT METHOD FOR HEAT TRANSFER WITH PHASE CHANGE IN FROZEN SOIL

摘要

This paper deals with a finite element analysis of heat transfer with phase change in frozen soil in terms of the transient temperature field and the thermally induced solid-solid phase transformations. By analyzing the shortcomings of the traditional finite element method in solving the phase change problem and the characteristics of the freezing process in frozen soil, the extended finite element method was proposed to solve the heat transfer problem with phase change for permafrost engineering. Taking a quadrilateral element as an example, the extended finite element method interpolating function and solution format of the temperature field with phase change was derived. According to studies on constructing and solving the level set function, building of the stiffness matrix, and the subdivision of the elements, a program for heat transfer with phase change was proposed. The numerical solution is in good agreement with the measured value.