Hi lads! Im new to the forum though Ive been interested in pulsejets for a while now. So much so actually that I decided to design, build and analyse the operation of one for my final year project in university!
Ive the majority of the design work done now thanks to CE Tharrats "The Propulsive Duct" and Bruce Simpsons book.
Im using a tailpipe of 78.1mm ID since its easy to get hold of in seamless mild steel tubing so the size of the jet worked from that. This works out at 16.35lb thrust calculated. Now Ive designed a petal valve plate to try and make the most of a given size while keeping hole width to below 0.5" and keeping the total intake area to the required 0.23*A. Now with that configuration, the diameter of the valve plate and, hence, the front section of the engine is going to be only 3.49" or 88.8mm. This seems like a very small increase in diameter over what i was expecting... The question is, is it practical to have "orange segment" shaped intake holes in the valve plate of does the position of the inner portions of the holes reduce the efficiency due to having to pass across the outer part of the hole before entering the engine?
The other question is what, in yer experience is a nice overlap for the valves on the plate? Should I be going over 1mm? 2mm? At the moment I have less than 1mm, unless I can cut the valves to have a less than 1mm cut between the petals. Im afraid it might be too harsh on the plate? My intended valve plate material is anodised aluminium.
Thanks. I will keep ye posted on how the project goes...
Valve overlap and other stuff...
Moderator: Mike Everman