Numerical Simulation Study On Effect Of Gravity Heat Pipe On Distribution Of Coal Fired Spontaneous Combustion Temperature Field

As we all know,our country's primary energy is mainly coal and this will not be changed for a long time in the future.Spontaneous coal combustion is a major challenge for coal storage and transportation and safety management of coal mine.Large coal storage sites and coal gangue piles stacked randomly can easily lead to spontaneous combustion of coal piles and this is the main safety issue.In recent years,the successful application of gravity heat pipe technology in cold area engineering,air conditioning,refrigerating and other fields had drawn the attention of relevant scholars to put forward the idea of applying gravity heat pipe technology to coal mines or coal gangue hill to prevent spontaneous combustion.At present,the basic theory of gravity heat pipe technology is relatively matured,but to successfully apply the method of self-ignition of the heat pipe to remove heat and prevent coal combustion,there are still many key scientific issues that need to be studied.Spontaneous coal combustion is a major challenge for coal storage and transportation and safety management of coal mine.Large coal storage sites and coal gangue piles stacked randomly can easily lead to spontaneous combustion of coal piles and this is the main safety issue.In recent years,the successful application of gravity heat pipe technology in cold area engineering,air conditioning,refrigerating and other fields had drawn the attention of relevant scholars,and put forward the idea of applying gravity heat pipe technology to coal mines or coal gangue hill to prevent spontaneous combustion.At present,the basic theory of gravity heat pipe technology is relatively matured,but to successfully apply the method of self-ignition of the heat pipe to remove heat and prevent coal combustion,there are still many key scientific issues that need to be studied.The research shows that the internal migration of the coal pile in high-temperature zone is a dynamic change process.The temperature rises slowly in the early stage.On the 60th day,the high temperature area is highly concentrated and tends toward both ends of the windward side.Effective prediction of the high-temperature area range of the 3D coal stack,where the coordinates of the left-hand area are approximated as follows:the x direction is between(2.5,5.5)m,the y direction is between(1,6)m,and the z direction is taken The value is between(0.3)m.The right area is determined by mirroring the corresponding range in sequence.The specific scheme inserts the gravity heat pipe in the high temperature region of the 3D coal stack to arrange and optimize the cooling scheme of the coal stack.The study shows that the gravity of the model of the heat pipe inserted into the bottom of the coal stack has the best cooling effect(ie,Z = 0m),and should not be greater than 0.5m.The distance between the gravity heat pipes arranged in the X direction should be lm,not more than 1.5m;the spacing along the Y direction should be taken as 1m.