DieselShip's Online Content Library

13. A counter flow shell and tube oil cooler has 100 tubes of inside diameter 25 mm and wall thickness 2.5 mm. The tubes are each 2.8 m long. Oil flows in the tubes and water in the shell. The surface heat transfer coefficient on the oil side is 950 W/m² K. The oil enters at a temperature of 82°C and leaves at 45°C and the water enters at 18°C. The mass flow rate of the oil is 8 kg/s and that of the water is 25 kg/s. The specific heat capacities are 2.0 kJ/kg K and 4.2 kJ/kg K for oil and water respectively. Determine EACH of the following:

(a) The rate of heat transfer;

(b) The logarithmic mean temperature difference;

(c) The surface heat transfer coefficient on the water side.