A 15-m-long section of Air smooth circular duct of 20 cm diameter passes through cold water at a costent temperature of 15 oC. Air at 1 atm enters the duct at 25 oC at a velocity of 3 m/s. Assuming the surface of the duct to be at the temperature of the water, 1) Sketch the problem showing all information needed 2) Perform an energy balance on the air inside the pipe 3) Apply Newton's cooling law for heat lost by the air 4) Using equations in 2) and 3) calculate the air exit temperature 5) Using the LMTD calculate the exiting temperature and compare it to that in 4) 6) Calculate the heat lost by the air 7) Do you need to redo the calculations if the air pressure is changed to 3 atm? Redo 5) and compare it to 1 atm) 2.33 x 8) Going back to the original problem calculate the heat lost by air if the circular duct is replaced by a 106 m roughness pipe. 9) Going back to the original problem, if the velocity of air at 1 atm is reduced to 0.1 m/s calculate heat transfer rate at the middle length of the pipe 10) Going back to the original problem, If the velocity of air at 1 atm is reduced to 0.1 m/s calculate the heat transfer rate at the end of the pipe and compare it to the base case of 3 m/s 11) Going back to the original problem, If the velocity of air at 1 atm is reduced to 0.1 m/s calculate the fan power used to move the air and compare it to the base case of 3m/s