Optimizing energy consumption in hot air furnaces

Abstract

The hot air furnace is used to heat interconnected and integrated spaces. This heating device works as a gas-to-gas heat exchanger, and one of its main problems is that its overall heat transfer coefficient is low. To improve the thermal performance of this type of heating equipment, it is possible to increase the area and duration of heat exchange or to disrupt the thermal boundary layer by installing flow barriers. Accordingly, in this study, the thermal efficiency of a new sample of hot air furnace has been investigated by installing a flow barrier and increasing the heat exchange area, etc. According to the results, the thermal efficiency of the new hot air furnace is seventy-nine and a half percent and the efficiency of the same hot air furnace available in the market is seventy-three percent. The relevant economic analysis also shows that the return time of additional investment for the new sample, assuming the average operating temperature of the hot air furnace (in the three months of winter, equal to twelve hours per day and assuming twenty-five working days per month), The basis of subsidy prices (the price of each cubic meter of gas is one hundred tomans) is equal to fifty-three months, and based on the export rates (each cubic meter of gas is one thousand two hundred tomans), it is equal to five and a half months. As is well known, it is economical to optimize gas consumption in hot air furnaces in both cases (evaluation at subsidized rates or export rates).