GATE MT 2022 Q45

Air at 300 K is passed at a mass flow rate of 1.5 kgs1  through a metallic tube of inner diameter 0.08 m. Inner wall temperature of the tube is maintained at 700 K. Temperature of the air leaving the tube is 600 K. Assuming that heat transfer occurs entirely by steady state convection, length of the tube is ______ m (round off to 2 decimal places).

Given: the coefficient of convective heat transfer from tube wall to air is 500 Wm² K¹. Assume specific heat capacity of air to be constant and equal to 1080 Jkg¹K¹  and π = 3.14