Repeat Problem 8.1 but assume that a fouling factor on the inside of the tube of 0.00018 (m2 K)/W has developed during operation.From Problem 8.1: In a heat exchanger, air flows over brass tubes of 1.8 cm ID and 2.1 cm OD that contain steam. The convective heat-transfer coefficients on the air and steam sides of the tubes are 70 W/(m2 K) and 210 W/(m2 K), respectively. Calculate the overall heat transfer coefficient for the heat exchanger(a) Based on the inner tube area,(b) Based on the outer tube area.GIVENAir flow over brass tube containing steamTube diametersInside (Di) = 1.8 cm = 0.018 mOutside (Do) = 2.1 cm = 0.021 mConvective heat transfer coefficientsAir side (ho) = 70 W/(m2 K)Steam side (hi) = 210 W/(m2 K)Fouling factor on the inside of the tube (Rd) = 0.0018 (m2 K)/WASSUMPTIONSThe heat transfer coefficients are uniform over the transfersurfaces

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Do- 2.1 cm Di=1.8 cm Steem Air