Experimental Study And Numerical Simulation Of Temperature Distribution In Coal Storage Silo With Internal Heat Source

As an environmental protection technical renovation project of power plant coal yard,coal storage silo not only greatly improves coal storage capacity,but also can effectively reduce dust pollution,which is of great significance for environmental protection and economic development of enterprises.However,in the process of coal storage,due to the physical and chemical properties of the coal itself,the heat in the limited confined space cannot be diffused,which leads to spontaneous combustion or explosion of the coal oxidation and temperature rise.Therefore,it poses a great threat to the safe and effective operation of the power plant.Researching the temperature distribution of loose coal and realizing the location of high temperature heat source point in coal silo are the premise of solving the spontaneous combustion problem.On the basis of previous research results,this paper adopts the method of combining experimental research and numerical simulation.Firstly,a small coal storage silo model is built in the laboratory for the experimental study of active temperature field.At the same time,finite element software is used to establish the finite element model of small coal storage silo.By calculating the model loading load,the distribution law of active temperature field in coal storage silo is obtained.The experimental results and numerical simulation results are compared and analyzed to obtain the distribution law of temperature field and the influence range of heat source under different temperature and different position of heat source.When the experimental data and the simulated data are highly similar,the active temperature field of coal storage silo in power plant is simulated numerically,and the temperature field distribution in actual coal storage silo with high temperature heat source is obtained.Finally,on the basis of numerical simulation,the relationship between the temperature of the high temperature heat source and the distance and temperature of the surrounding measuring points is fitted and verified,which provides a new idea for the location of the high temperature heat source in the coal silo and provides theoretical guidance for the later inerting protection.Through the comparison and analysis between the experimental results and the numerical simulation results of coal storage silo temperature field,it can be concluded that: The temperature distribution of the loose coal body in the coal silo is related to the intensity,time,distance and other factors of the heat source.The influence of heat source intensity is obvious,indicating that it is difficult to monitor the low temperature heat source;The direction of convection heat transfer caused by buoyancy is vertical upward,that is,the temperature of coal above the heat source is higher than that below the heat source;When the distance from the heat source is within 0.38 m,the heat conduction occupies a dominant position.When the distance is greater than 0.38 m,convection begins to play a role,and it plays its maximum role at the position 1 m away from the heat source;By simulating the actual coal storage silo within active temperature field distribution,the intensity can be obtained for more than 200?,its scope has been more than 5 m,on the basis of optimized layout of measuring points,no dead Angle can be continuously monitor coal temperature,ensure safe operation;The relations between the temperature and position of the heat source and that of the temperature measuring point were obtained by fitting the simulated data.Under certain conditions,the temperature and position of the internal hightemperature heat source could be deduced from the temperature value of the temperature measuring point.