Finite Element Modeling of Thermal Mechanical Coupling in Thermal Recovery Wells

摘要

In thermal recovery wells, the temperature of heat steam is very high and casing is heated during steam injection process, which has become the main reason of casing failure. Therefore, it is very important to analyze the thermal mechanical coupling in thermal recovery wells. Finite element modeling of thermal mechanical coupling for thermal recovery wells is analyzed as basis of ADINA. Three-dimensional finite element model is investigated; geometry model is constructed with native and parasolid method in ADINA. The casing is modeled by native method and strata are modeled by parasolid method, casing are subtracted and merged with strata by Boolean Operation. Gravity and displacement loads are defined in structure model, and temperature load in thermal model.In thermal model, all materials are treated as heat conduction material. Thermal-mechanical coupling is calculated with the thermo-mechanical coupled analysis solver in ADINA. According to the calculating results of thermal-mechanical coupling, the mechanism of casing damage is analyzed. Finally, some advice is proposed to prolong the casing life of thermal recovery wells.