Turkish Journal of Engineering and Environmental Sciences

Abstract: In this study, the general exergy balance of a system was analyzed based on the variation of the temperature of the surroundings. Using this balance, the mathematical equations regarding both the reversible work given to the system in the electric arc furnace used in steel production and the exergy loss in the rotary burner used in cement production were obtained. The assumption that the temperature of the surroundings has a sinusoidal change was made in obtaining these equations. The changes of the exergy expressions and the temperature of the surroundings within a day are presented graphically.

Key Words: Variable surroundings temperature, Exergy balance