Yang Lanhe
(College of Mineral Resource and Earth Science,China University of Mining & Technology, Xuzhou 221008, China)
Abstract：Based on the theories of heat transmission, plasto-elasticity and seepage flow mechanics, the coupled mathematical models of temperature field of gasification coal seam, seepage flow field of dry distillation gas, and deformation field of coal body are established. It is found that in the process of underground coal gasification, because of the high temperature effect, physico-mechanical parameters are not constant any more but become a function of temperature. In order to increase the calculation accuracy, the standardized thermal tendency of the physico-mechanical parameters are studied. The finite element method is used to solve the coupled models, and the calculated results are analyzed through a real example. According to the calculated results, compared with isothermal condition, the fitting degree of the measured values for dry distillation gas under nonisothermal condition is obviously better, and the measured values are higher than the theoretical ones. The agreement between the calculated and measured values indicates that the simulation are effective.
Keywords：underground coal gasification;dry distillation gas;temperature field;seepage flow
field;stress field;couple;numerical simulation