Hot air at an average temperature of 100 degC flows through a 3 m long tube with an inside diameter of 60 mm. The temperature of the tube is 20 degC along its entire length. The average convective film coefficient is 20.1 W/m2*K. what is most nearly the rate of convective heat transfer from the air to the tube?

An air compression refrigeration system is to have an air pressure of 100 psia in the brine tank and an allowable air temperature increase of 60°f for standard vapor compression cycle temperatures of 77 f entering the expansion cylinder and 14 f entering the compression cylinder, calculate the coefficient of performance a. 2.5 b 3.3 c. 4.0 d. 5.0