A tubular heat exchanger is being used for heating a liquid food from 30^oC to 70^oC. The temperature of the heating medium decreases from 90^o to 60^oC.

a) Is the flow configuration counter current or concurrent flow? Why?

b) Determine the log mean temperature difference.

c) If the heat transfer area is 20 m² and the overall heat transfer coefficient is 100 W/m² .^oC, determine the rate of heat transfer from the heating medium to the liquid food.

d) What is the flow rate of the liquid food if the specific heat of the liquid is 3.9 kJ/kg ^oC? Assume no heat loss to the surroundings.