> I?ve downloaded the NACA Submerged Inlet Data drawing provided by I > believe, Mark Langford, but after working all night I?m having some > trouble understanding the direction of airflow through the duct. For > explanation ease let?s consider an airplane flying left to right with > the airflow right to left over the fuselage. To act as an inlet, does > the narrow, shallow end point into the airflow? Conversely, to use as an > airflow exit duct does the broad end face forwards?
Does the photo at http://home.hiwaay.net/~langford/nacaducts/02082310.jpg give you a clue? Basically, you put the small end whereever the high speed air is, and the wide end where you're trying to slow the flow down (such as your engine's cylinder fins). Hence, since I have slow air coming out of my cowling and want to re-accelerate it back to the free stream speed that the airplane is seeing, the small end faces rear for this application, but would face forward if you were trying to duct air to the carb, engine, or interior. Mark Langford, Huntsville, AL N56ML "at" hiwaay.net see KR2S project at http://home.hiwaay.net/~langford
