Liquid water enters a cooling tower operating at steady state at 40°C with a mass flow rate of 10s kg/hr Cooled water at 25°C exits the cooling tower at the same mass flow rate. Makeup water is supplied at 23℃ Atmospheric air enters the tower at 30°C, 1 bar, 35% relative humidity. A saturated moist air stream exits at 34°C, 1 bar. Ignoring the effects of KE and PE, determine

a. The mass flow rate of the dry air and makeup water, each in kg/hr
b. The rate of exergy destruction within the cooling tower, in kW, for To 23°C

Along 8-cm diameter steam pipe whose external surface temperature is 900c connects two buildings. the pipe is exposed to ambient air at 70c with a wind speed of 50 km/hr blowing across the pipe. determine the heat loss from the pipe per unit length. (b) air at 500c enters a section of a rectangular duct (15 cm x 20 cm) at an average velocity of 7 m/s. if the walls of the duct are maintained at 100c. a) the length of the tube for an exit temperature of the air to be 40 0c. b)the rate of heat transfer from the air. c) the fan power needed to overcome the pressure drop in this section of the duct.