An engine oil cooler consists of a bundle of 25 smooth tubes, each of length 2.5 m and diameter 10 mm. If oil at 300 K and a total flow rate of 22 kg/s is in fully developed flow through the tubes, what is the pressure drop, in bar, and the pump power requirement, in kW

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.