冻土墙墙体时空扩展过程中热能消耗的有限元分析

FEM Analysis of Heat Energy Exhaust During Space-time Expending of Frozen Wall

用于人工冻土墙形成过程相关计算的 Sanger- Sayles经验公式是 ,Fourier热传导方程在单值热物理参数轴对称条件下的求解结果 ,对结构形成过程中冻结管吸热的计算采用了不合理的温度分布假设 ,计算结果不能令人满意。运用有限元分析程序 ,完成了对热物理参数非线性变化土体材料的人工冻结过程的计算分析 ,模拟了冻土墙时空扩展过程 ,研究了土体内的温度分布以及能量消耗等问题 ,在此基础上推导出的关于冻结过程的能量消耗计算的一般形式 ,对人工冻土墙的工程设计具有重要的指导意义。

Sanger-Sayles formula, a method frequently used in thermal calculation of artificial frozen wall expending, is the solution of Fourier′s thermal equation describing the axisymmetric problem with single value of thermal physical parameters. The unreasonable temperature distribution hypothesis adopted into the calculation of absorbed heat energy by freezing pipes made the result dissatisfactory. In this paper, based on FEM, the computational analysis is made of the process of artificially freezing the soil with nonlinear changing thermal physical parameters, the frozen wall expending process is simulated, and the problems such as inner soil temperature distribution and energy exhaust are thoroughly studied. The general form concerning the energy exhaust during freezing contains the significant instructive sense to engineering design of the artificial frozen wall.