Experimental Study Of Heat Pipe Layout Parameters And Environmental Wind Speed On Coal Reactor Heat Transfer

At present,the prevention and control measures for spontaneous combustion of coal heap have high cost and no obvious effect in practical application,some control methods can not eliminate the factors of spontaneous combustion of the coal heap in essence.Under this background,the heat pipe heat transfer technology that have the effect of recyclable and efficient characteristic provide a new way to solve the coal spontaneous combustion.In this paper,we analysis the heat turnover process of the "heat pipe-coal heap" system,clear some key factors to the heat transfer in the heat turnover process,use the coal heap-heat pipe heat transfer experiment table,measure temperature data by the thermal resistance,temperature monitor and other monitor instruments,adjust the heating temperature 100?and 150?to the coal heap,heat pipe insertion ratio 1/4,1/3and 1/2 in the coal heap,angle of the heat pipe insertion 45°,60°and90°,wind speed out of the coal heap from no wind condition,1.5m/s to the 2m/s,study the heat pipe influence radius in the coal heap,axial temperature difference on the heat pipe surface,and the change rule about the heat pipe heat transfer to the coal heap in the effective work time,we can come to the follow conclusion by analysis the experimental data:(1)Under the 100?heat temperature,the temperature drop and the temperature transfer in coal heap temperature field is taper caused by the heat pipe,change with the insertion ratio gradually increasing,heat pipe get the highest heat transfer efficiency at the 1/4 insertion ratio;under the 150?heat temperature,the temperature drop and the temperature transfer in coal heap temperature field is gradually increasing caused by the heat pipe,change with the insertion ratio gradually increasing,heat pipe get the highest heat transfer efficiency at the 1/2 insertion ratio;analysis the different experimental result of the different angle of insertion,we can come to the heat transfer relationship:60°>45°>90°,it is that the heat pipe get the highest heat transfer efficiency when the heat pipe have appropriate amount angle of highest heat transfer efficiency when the heat pipe have appropriate amount angle of inclination;(2)The wind speed change process from 0m/s,1.5m/s to the 2m/s,the temperature drop at the first temperature measurement point average increase is 46.3%,when the angle of the heat pipe is 45°,it is the 32.8%,when the angle of the heat pipe is 90°,it is the 10.8%,when the angle of the heat pipe is 60°,it shows that under the 45°experimental condition,the heat transfer have great influence,more sensitive to the wind,the angle of the heat pipe inclination have great influence to the heat pipe heat transfer,under wind free environment,the transfer efficiency improve 107%when the angle change from 45°to 60°;it is improve 11.6%when the angle change from 90°to 60°;both of them improve 76%.when the wind speed is 1.5m/s;it is improve the 79%and 3%when wind speed is 2m/s,compare with the vertical insertion condition,appropriate amount of decline angle promote the heat extraction,when the heat pipe have 60°with the wind direction,it have the least axial temperature difference on the heat pipe surface and it get the highest heat transfer at the same time.