Pressure no, but volume is no problem -- that's what every ejector does. The resultant gas mix is slower than the driving jet stream, but MUCH denser and cooler. This should work well if you get it into the front end of a properly designed diffuser.Viv wrote:I would question the ability of the recirculated exhaust gas to usefully add pressure or volume to the intake by entrainment
Like, for instance, the energy taken up by a turbine? ;-)... any energy taken from the exhaust is lost to propulsion
What makes this a given? What if the losses somewhat, but not quite, negate the gains? If you have that, the rest is just tuning.... the losses will add up and negate the gains.
The first "successful" gas turbine was the 1905 Armengaud-Lamale turbine, which was big enough to take months to build and weighed many tons. When they fired this baby up, they were able to get a whopping ONE PERCENT of the total combustion energy delivered to the shaft! If you were an investor, and these guys told you, "You know, this really proves that is IS practical -- the design just needs some more work to make it really good," what would you have said to that?
Yes, it is probably just my own ignorance that makes this look so great. NASA certainly didn't buy into my attempt at it:I would recommend Foa's book on propulsion as it covers these types of engine and other interesting types as well.
http://www.cottrillcyclodyne.com/Cyclod ... ction.html