Air enters a frictionless, constant-area duct with
M1 5 2.0, T1 5 300R, and p1 5 70 psia. Heat transfer occurs
as the air travels down the duct. A converging section
(A2/A3 5 1.5) is placed at the end of the constant area duct
and M3 5 1.0. Assuming isentropic flow (aside from the heat
transfer through the duct), calculate the amount and direction of heat transfer.