There are two concentric pipes. The outer pipe is ejecting air at 10 atm and 1200K. The inner pipe is ejecting air at 1 atm and 600K.Mass flow rate is the same and the air is being ejected into a common duct. What will happen? Will the the two flows mix together in the common duct producing a medium pressure and medium temperature or will the outer pipe exert backpressure on the inner one preventing the air from getting out?