Experimental heat transfer performance evaluation of a novel multi electric injera bakery

Injera is daily cooked using conventional electric mitad or stove. It has low efficiency in the range of 45-55 %. This stove takes 14 min to heat up and another 3 min to make single Injera. The system has 50-60 % heat loss, of which bottom loss contributes 35.08 % (or 1.2 kW). In this paper, "an efficient multi electric mitad Injera bakery"is introduced that makes four Injera simultaneously. This bakery was manufactured by stacking vertically four decked electric mitads at a characteristic gap of 20 cm in a single column insulated cabin. The thermal performance of the bakery was evaluated using experimentally collected data. The heat up time, percentage total heat loss and efficiency of the four mitads (top-To-down) during simultaneous non-baking operation were found to be 10, 8, 7& 9 min; 31.7, 22.6, 18.2 & 26.9 % and 68.2, 77.3, 81.7 & 73.0 %, respectively. The average efficiency of the bakery in making four Injera simultaneously was 85.3 % with a lead time of 1.3 min. These results indicated that stacked arrangements of electric mitads is more efficient than the conventional stove with reduced cooking & heat up time that would significantly save electricity.