An oil cooler for a large diesel engine is to cool engine oilfrom 60 to 45 °C, using seawater at an inlet temperature of 20 °Cwith a temperature rise of 15 °C. The design heat load is 140 kW,and the mean overall heat transfer coefficient based on the outersurface area of the tubes us 70 W/m2°C. Calculate the heat transfersurface area for single pass (a)- counter flow and (b)- parallelflow arrangements.
