Water flowing at a rate of 10 kg/s through 50 tubes in a 2 – 1 pass heat exchanger heats air flowing on the shell side. The tubes are made of brass with an outside diameter 2.6 cm and 6.7 m long....

Water flowing at a rate of 10 kg/s through 50 tubes in a 2 – 1 pass heat exchanger heats air flowing on the shell side. The tubes are made of brass with an outside diameter 2.6 cm and 6.7 m long. Surface coefficients on the inside and outside tube surfaces are 470 and 210 W/m2 ·K, respectively. Air enters the unit at 15 °C with a flow rate of 16 kg/s. The entering water temperature is 350 K. Calculate the following; a) The heat exchanger effectiveness, b) Heat transfer rate to the air, c) Exit temperatures of water and air streams.