人工多圈管冻结水热耦合数值模拟研究

人工多圈管冻结过程中温度场和水分场的计算,是一个多物理场耦合和非线性数学问题,其影响因素多、相互之间关系复杂。基于相似理论原理和人工多圈管冻结模型试验,提出渗流方程中的导水系数是温度梯度的函数,建立了多圈管正冻土中水热耦合数学模型,并采用有限元方法实现了对多圈管冻结温度场和水分场耦合的数值分析。数值模拟温度场的发展趋势、水分场迁移特征与模型试验吻合良好,表明用提出的水热耦合数学模型计算多圈管冻结温度场和水分场是可行的,对多圈管冻结壁设计有参考意义。

RESEARCH ON HYDRO-THERMAL COUPLING NUMERICAL SIMULATION WITH ARTIFICIAL MULTI-FREEZING-TUBE CYCLES

During the coupling analysis of moisture field and temperature field in freezing soil by using artificial multi-freezing-tube cycles,a lot of factors should be considered,including multi-fields and nonlinear problems,etc..Their relations are complicated.The model tests of freezing process with multi-freezing-tube cycles are conducted.The regulation of variation of temperature field and moisture field with freezing time are obtained.It is proved that the temperature is the source of variation of moisture field;and the hydro-thermal coupling dominant equation is proposed.The finite element method is used to carry out hydro-thermal coupling movement with the hydro-thermal coupling parameters being solved simultaneously.It can simulate the characters of temperature forming and development,freezing moisture field transferring,as well as the coupling relation of the two fields.The results of numerical simulations and model tests have good coincidence.The hydro-thermal coupling analysis in this study has important reference to designing and optimizing freezing wall.The results have promotion role for both technological progress and theoretical development of shaft sinking by artificial freezing process with multi-freezing-tube-cycles in thick overburden.