Numerical Simulation And Application Of Soil Temperature Field Around Buried Thermal Pipeline

Underground pipelines are often used for petroleum transportation.In the process of pipeline operation,in order to optimize the pipeline construction and formulate a scientific and reasonable hot oil transportation process,it is necessary to master the temperature drop and the temperature field around the pipeline in the process of pipeline operation.On the basis of establishing the physical model of soil temperature field around buried oil pipeline,considering the temperature variation of lateral and longitudinal soil around the pipeline.Then a three dimensional operation model of soil temperature field is established,which makes the simulation of soil temperature field more closer to reality.The main research contents include: for the oil pipeline investigation and theoretical discussion,building a physical model of buried oil pipeline in non steady state,meshing the model by Gambit.And the influence of pipe depth,pipe radius and crude oil velocity on the soil temperature field around the pipeline was simulated by Fluent software.,the simulation data postprocessing temperature field distribution can be using Tecplot software to deal with,calculate the working oil temperature drop and pipeline pipeline safety shutdown time.The calculation results show that these factors have great influence on the oil temperature change in the pipe,and the influence should be fully considered in the optimization of pipeline construction and the formulation of scientific and reasonable conveying process.In the study of soil temperature field around the buried pipeline at the same time,also conducted heat pipe heat diffusion application experimental study on performance of snowmelt experimental apparatus using the obtained experimental data,the snow melting time and snowmelt load,which is of certain significance to carry out the application research of thermal melting system.The main work done in this paper is:(1)The finite element method is used to calculate the soil temperature field around the pipeline under different buried depth.The results show that under the same conditions,the deeper the buried pipeline,the less heat dissipation and the longer the shutdown time.(2)Numerical simulation of the variation of soil temperature field around the pipeline when transporting crude oil with the different temperatures.From the calculation results,it can be seen that the higher the oil temperature,the greater the thermal influence range of the horizontal direction of the pipeline,the faster the temperature drop,and the greater the allowable shutdown time.(3)Numerical simulation of flow velocity at different exit stations.The greater the crude oil flow rate in the pipeline,the less heat emitted by the hot oil pipeline to the surroundings,and the lower the crude oil temperature drop in the hot oil pipeline,the longer the shutdown time is allowed.(4)Carrying out the study on thermal diffusion of heat pipe,getting the influence of snowmelt time under different conditions,and calculate snow melting load,which has certain guiding significance for the study of buried pipeline operation condition under snow condition.