Originally Posted by FlyGood
For Dan: For your converging oil cooler exit duct, what is the ratio of the duct exit area at the bottom of the cowl to the area at the exit of the cooler?
It does not extend all the way to the freestream, but rather to the top of a converging exit bell exhausting all the cowl air. Oil cooler mass flow meets the majority mass flow at a right angle, more or less, so I didn't want significant velocity. So, if
the duct exit is smaller than the cooler face area, it is not by much. The area was set by the available space between engine mount tubes. I do not know the exact area.