Study On Freezing Temperature Field With Freezing Pipes Divergent Arranged

The project about sealing water with freezing method in the Tunnel between theChaojunbeilu station and the Chaoan station in the Guang-fo line was arranged divergentfreezing pipes in bottom section of tunnel to seal the water. The dissertation combined thenumerical simulation research and simulation experiment research to get the law of thetemperature field.Built the finite element model with Structure analysis soft ANSYS to study the variousfactors’ influence on temperature field and get the regression formulas with the single factoranalysis; orthogonal experiment analysis and multiple regression analysis. Through the singlefactor analysis, got the conclusions that the thickness of frozen wall decreased with theincreasing of initial soil temperature or the angle between adjacent freezing pipes, whileincreased with the increasing of row spacing or the decreasing of the outside wall temperature infreezing pipes. In addition, the influence of the soil frozen temperature is not obvious. While thelaw of the average temperature was opposite to the thickness of frozen wall. While the influenceof the row spacing made the average temperature first decrease then increase. The dissertationgot the significant influence factors through the orthogonal experiment analysis, and got the mostsignificant factors for the thickness of frozen wall were the outside wall temperature in freezingpipes and the angle between adjacent freezing pipes. And the most significant factors for theaverage temperature of the frozen wall were the outside wall temperature in freezing pipes; theangle between adjacent freezing pipes and the the row spacing. And then got the regressionformulas of the thickness and average temperature of frozen wall through the multiple regressionanalysis.Studied the temperature field of the two models with different angles10oand14obetweenadjacent freezing pipes through the simulation experiment research. Analyzed the developmentand distribution law of the measuring point on the feature face. And then compared thetemperature field of two models to analyze the similarities and differences. The experimentalresults show that the development of the temperature field in the interface is lower than thetemperature field in the main surface In the early stage, and latterly they have been similar.Increase the angle between adjacent freezing pipes will made the thickness of frozen walldecrease and the average temperature rise, but it made the range of the frozen wall increase. Thedissertation got the fitting formulas of the thickness and the average temperature of frozen wallby fitting the data of the experiments. And then got the formulas of temperature field development speed with the derivation of the fitting formulas.The dissertation compared the numerical simulation research and simulation experimentresearch through the results of temperature field. And got the conclusion that the laws oftemperature field got from the two methods were similar. but the data of simulation experimentresearch were less than numerical simulation research. And in the area of freezing pipes, thenumerical simulation research could represent the temperature field exactly.In conclusion, the factors had some degree impact on the temperature field with divergentarranged freezing pipes. while the outside wall temperature in freezing pipes; the angle betweenadjacent freezing pipes and the the row spacing were more significant. The experiment processshould be strictly controlled to avoid the experimental errors. The regression formulas and thefitting formulas of the thickness of frozen wall and the average temperature in this dissertationhad a certain reference to related projects.