> Russell McMahon wrote: > > I hereby release this idea into the public domain, to join "my" pistonless piston pump concept, always providing it hasn't already been thought up numerous times already in the last century or so, as the PPP already has ;-) > > Dare I ask?
No :-) But, the PPP is a Pistonless Piston Pump ** - a rocket propellant pump that uses 2 x 2 way valves and a few non return valves per propellant, is gas powered, has essentially no other moving parts and is equivalent or superior in key specification to some turbo-pumps, and more than an order magnitude easier to develop & make. And much cheaper. Unlike turbo-pumps it is within the realistic reach of manufacturing by many amateurs. I presented the idea on the ARocket list some years ago as an idea that was original as far as I was concerned, but which was so obvious in retrospect that it seemed likely to have been "invented" numerous times over the decades. Such proved to be the case. "It steam engines come steam engine time. " Steve Harrington of Flometrics (frequent contributor on the ARocket list) was secretly working on much the same idea. The Flometrics patented "pistonless pump" is essentially my idea, but arrived at independently. Henry subsequently advised that Lockheed had patented a similar device - its details show they had been secretly copying my ideas about 4 years before I thought any of them up* :-) and Steve has searched ancient literature and found similar devices described in the 1960s. >From my own subsequent research - The Humphrey Pump run by the Cobdogla Steam Engine Society in Australia and installed about ?1920 is essentially a half cycle version of the same thing but bizarrely executed and magnificent in its scale. It is INTERNAL COMBUSTION using coal gas and using the pumped fluid (water) as the piston and a resonant 4 stroke cycle. AFAIR bore is about 10 feet and stroke similar !!! I believe that somebody's incarnation of the PPP is going to have a significant role in rocketry in the future - whether as first stage pumps or for space use. I'm sure Steve agrees :-). See http://www.flometrics.com/rockets/rocket_pump/rocketpump.htm for Flometrics version. Russell McMahon * I have a whole collection of similar world beating ideas. I know they must be because I subsequently find that a number of them have been patented and implemented successfully by other people years or decades before I think of them. :-). ** Henry Spencer is responsible for the "Pistonless Piston Pump" name - he said something like "... it's a piston pump without a piston...". Sounded good to me. _______________________________________________ ERPS-list mailing list [EMAIL PROTECTED] http://lists.erps.org/mailman/listinfo/erps-list
