Study On Mechanism Of Abnormal Surface Temperature Caused By Buried Heating Pipe Leakage

In northern China,the main heating measure in winter is central heating,while the leakage of heat pipes occurs frequently during the heating season.This not only brings more serious economic losses to the enterprise,but also affects people's quality of life,resulting in the pollution of water resources and environment and even threatening personal safety.At present,the technology used in detecting thermal pipeline leakages in enterprises is relatively backward.In addition,it is very difficult to detect the leaks of buried pipeline due to the topography and environment,so it is very important to find the leak and find the exact location for the leakages.,Not only can reduce the group's economic operating costs,but also ensure people's quality of life in winter and their own safety.Based on the infrared thermal imaging technology,according to the characteristics of the soil temperature and humidity changes when the pipe insulation is damaged and the pipeline is leaking,a test device similar in structure to the actual engineering buried heat pipe is constructed.This small-scale test platform is used to analyze the heat and mass transfer mechanism of buried heat pipe in intact insulation,damaged insulation in different directions and leakage of pipes in different directions.With the rapid development of computer,numerical simulation of heat and mass transfer has become an effective method.Taking full account of the external environment,the Fluent simulation software is used to simulate the temperature and humidity of buried heat pipe under different working conditions.Field distribution simulation,compared with the experimental data and corrections to verify the relevant parameters of the feasibility of numerical simulation.Based on this,the accurate soil physical parameters needed to simulate buried heat pipelines are obtained.Combined with the measurement of soil temperature and humidity in the anomalous area after detecting the surface temperature anomaly by the infrared thermal imager in actual project detection,the actual detected leakage conditions and the correlative physical parameters are simulated.In the end,the criterion of leakage of buried heat pipe was obtained by combining the experiment and simulation-simulation and actual research,which provided a scientific and accurate basis for the actual engineering inspection.