The overall heat transfer coefficient for a shell and tube heat exchanger for clean surface The fouling factor after one year is 3000 W is 400 W/m²K m-K heat transfer coefficient for the impure fluid in the heat exchanger. Now calculate the a) 353 W/m²-K b) 333 W 3 W/m²-K c) 433 W W/m²K d) 453 W 53 W/m². m2.K