制冷液温度对地下冷冻墙制冷效果影响的有限元分析

Finite Element Analysis on the Influence of Cooling Liquid Temperature on the Refrigeration Effect of Underground Frozen Wall

油页岩原位开采、矿山竖井施工、基坑支护等工程中,常采用地下冷冻墙进行止水和护壁。在地下冷冻墙制冷系统中,制冷液温度影响冻结交圈时间,进而影响地下冷冻墙的制冷效率,更影响工程的施工成本及运行费用。通过有限元模拟,对制冷过程中地下温度场进行理论分析,得出制冷液温度对地下温度场的影响规律,并对制冷液温度进行优化,得到在制冷机组制冷或风冷制冷方式下,制冷液温度应在-10^-15℃较为合适的结论,为提高地下冷冻墙制冷效率提供理论指导。

For oil shale in-situ mining, mine shaft construction and foundation pit support, underground frozen wall should be built to prevent underground water flowing into the mining area and the leakage of oil and gas.Cooling liquid tempera-ture of underground frozen wall not only affects freezing closure time, but also affects the refrigeration efficiency of the un-derground frozen wall and further affects the entire costs of the construction and operation.By the finite element simulation and the theoretical analysis on the underground temperature field in the refrigeration process, the influence law of cooling fluid temperature on the underground temperature field was found and the cooling liquid temperature was optimized.It was concluded that under refrigeration modes of refrigeration unit or air cooling, the appropriate temperature of cooling fluid should be -10 to -15℃, which could be the theoretical guidance to improve the refrigeration efficiency of underground frozen wall.