The numbers I’m looking at are for relation reference only so 180kt inlet speed does not indicate the airspeed of the aircraft (for sake of argument.)

 

I have read that the airspeed needs to be reduced, hence the expansion from a 16 x 3 opening to a core frontal area of 200 sq in.) As a result of the expansion and drop in pressure, I realize that the air that reaches the core will be cooler than the air that enters the inlet.

 

From the radiator to the exhaust I’m looking at reducing to an opening size of approximately 75 sq inches. Based on what I have read this should slow the air down sufficiently to get it closer to a speed where it can absorb the most heat from the core. Some of the speeds I’ve been quoted have been in the neighborhood of 35 kts. I don’t know how accurate those numbers are.

 

The air is expanding to a greater volume after it passes through the radiator and is compressed due to the ducting which is supposed to result in enough thrust gain to cancel out 90+% of the drag created by the scoop.

 

I know that a 180 > 45 is close. I don’t know if I could get away with a smaller inlet or if a 4 to one ration is as far as I can push it.

 

T Mann