ORIGINAL: siclick33
What is the theory (in layman's terms) behind the thrust augmenting tailpipe? Is is simply a divergent duct increasing the exhaust pressure? if so, there is always a penalty to be paid and surely this would be in terms of exhaust gas velocity (and hence top speed).
I am still a believer that you don't get something for nothing.
Also, the thrust that is being measured by most people is static thrust. Does anyone know the magnitude of the benefit these "augmenting" pipes actually have in the air?
It would be really interesting to see a comparison with all else equal, and measure acceleration, top speed etc.
My thoughts are that maybe the efflux speed of the standard pipes are so high that the plane can't make good use of it, much like having a propeller with to much pitch.
Trading off 10% of the exhaust speed for 10% more static thrust might not show up on the top speed?
Hey you magazine guys, that would be a great article!
Lars