Feasibility Study On Shallow-buried Insulation Of Rural Water Supply Pipes In Severe Cold Areas

Problems in the water supply network in rural areas in Northeast China are enormous,and pipeline frost heave in winter are seriously bad.How to solve the issue of frost heaving in pipelines to ensure the safe and reliable operation of water supply pipe network in winter has become a difficult problem for engineers and scientific researchers.In view of the above problems,this paper proposes a technical method of shallow buried water supply pipe network insulation to ensure the normal operation of pipelines in winter.Next,the thermodynamic calculation equations of the water supply pipelines in the severe cold regions of northeast China were established to calculate the vertical temperature field variation regular pattern and the 0°C intrusion soil temperature.The optimal insulation layer thickness of the pipeline is obtained by calculating the length of the pipe without freezing and the temperature drop of the water at the end of the pipe under different insulated layer thicknesses,depths of depth,and water flow rates in the pipe.The freeze-thaw circle model was established to analyze the variation of the diameter of the freeze-thaw circle cryosphere under different influence factors,and the heat tra nsfer regular pattern of the shallow buried water supply pipeline.The temperature field model of the shallow buried insulation water supply pipeline was established by Fluent simulation software to verify the conditions under the temperature field around the pipe network under different buried depths,different insulation layer thicknesses,different insulation materials and different nominal diameters of water supply pipes and prove verified feasibility and safety of theoretical calculation Finally,using the actual water supply pipeline as a prototype,a test platform was set up.And slect typical pipe diameters and typical buried depths to test and verify the correctness and reliability of the thermodynamic calculations and simulation experiments were verified.Then,the security evaluation of the pipe network before and after the project was carried out to obtain the safety indicators of the insulation of the water supply pipeline.And a comparative analysis was performed to verify the superiority of the operation safety of the shallow buried insulation pipe.Through theoretical calculation,simulation analysis and field test,it is proved that the thermal insulation shallow buried technology of water supply pipelines in the severe cold regions of northeastern China has certain advantages over direct burial technology,in line with China’s national conditions.And it is recommended for popularization and application in severe cold regions.