Effect of Heating Element Positions on The Thermal Performance of Brick Tunnel Kiln: An Experimental Approach

This work experimentally investigates the effect of the heating element (electric coil) positions on the thermal performance of a brick tunnel kiln. A scale 1:4 test section has been utilized. Nine distinct heater positions were examined in the present experimental work, with Reynolds numbers (Re) ranging from 15,938 to 30,890, and as a result, Nusselt Numbers were found from 186 to 285 on most through all settings (nine settings tested), The thermal performance parameters were found to be dependent on the heater positions in each column in test section. The results revealed that at a maximum Reynolds number for each setting of the heating element, the average Nusselt number reached a maximum improvement of 48.8% for setting 2. The results show that the highest percent increase in the local Nusselt number, as the Reynolds number increased from the lowest value to the highest one in each setting, occurs in the longitudinal direction near the wall, reaching a percent value of about 55.7 and 51.3% for settings 2 and 9, respectively.