If you have a cylinder with a slightly larger diameter at one end (the intake end) Would having one ducted fan powered by it's own motor at intake end and a second ducted fan powered by it's own motor at the exhaust end produce more thrust? It seems like the already accelerated air coming from the intake fan would be "super accelerated" by the exhaust ducted fan? I purposely stated using two fans for reasons of experimenting/controlling fan RPMs separately and also my final design may not be a straight cylinder. The diameter of fans would probably need to be at least 12 inches for the power I'd need. Any suggestions by folks with real experience with larger ducted fans would greatly be appreciated.