Cass256 The Bourke engine was way ahead of its time. It was designed from the principles of high pressure, high temp, fast complete lean combustion that does not produce CO2 and is very economical, and has a great power to weight ratio. Before you would even think about using this type of engine in an aircraft it would need a massive lot of operational reliability testing in varying environments etc, etc. I am hoping one day soon to build one specifically for a paramotoring application, but that may never happen.
FYI - the write up on the 'bourke engine' in Wikipedia is very biased and bags the engine without really understanding it. There is a lot of misinformation surrounding this engine, yet it is not an unproven theory, there are functioning bourke engines currently in existence, and they are amazing!
Agreed, it's a relic of an age past for sure. I believe it was used for ease of manufacturing, honestly. Pistons & jugs were much easier to make than rotary engines in the 40s.For me, the Scotch Yoke is the deal breaker.
Years ago I was trying to design the simplest possible expansion engine. The kind of thing I could slap together in my apartment with a hack saw, drill and a set of files. No illusions of changing the world, just something unique I could say I designed myself. Somehow I always ended up at a Scotch Yoke in it somewhere and would have to move on to the next idea.For me, the Scotch Yoke is the deal breaker.
It will be fun to scheme and the essential parts have run well but not in same engine.If you're not familiar with this type of engine, here's an article and here's everything else you could want to know.
What are your guys thoughts on this type of engine?
I think the idea of using detonation for power is genius, and if the claimed performance specs are anywhere near true (weighed 38lbs, 30cu in. making 76hp at 10k rpm, burns 1gal/hr at 6500rpm ) it could be revolutionary not only for aviation, but the motor industry as a whole.
Would it be worth it to pursue designing a one-off of this design? As far as I can tell, the problem everyone's run into with the engine is fuel delivery. A standard carb just doesn't work, and the original #001 engine ran with a constant velocity carb. I think this would be a great candidate for FADEC, though I'm not confident I could pull that off myself. It supposedly runs very lean, giving it great efficiency. Burning less gas would be a major benefit in my plane, since I can only hold 10 gal.
If I were to pursue making one for my plane, do you guys have any suggestions for parts manufacturers/mechanical engineers that could help?
Since we are definitely on the "alternative engine" bandwagon, there is a really good writeup on Atkinson on Wiki: Atkinson cycle - WikipediaThe idea of the Atkinson cycle is to have a larger expansion stroke than compression stroke. We are limited on the compression ratio due to knock, octane and other things. But having a larger expansion ratio extracts more power for the given amount of fuel. Most modern car engines that use the Atkinson cycle do so by just holding open the valves during part of the compression stroke and this also increases pumping losses a little.
Another and maybe a better choice is an opposed piston engine with different phasing of the crank shafts. There is still a weight penalty since you are not "using" all of the possible cylinder volume but less pumping loss and no cylinder head weight. I think cheapracer was working on one of these in the past.
Cass256 and any others interested in detail discussion please PM me for further voice discussion. Single channel simplex communication via keyboard does not facilitate efficient communication.I am interested in designing an engine from scratch, not necessarily using off the shelf parts, and I know this is no small task/journey. Do you have any advice where I could start with this? Should I go get a mechanical engineering degree? Should I try to find other people who might be interested in working for me designing this? I'd like to create an RC scale version for bench testing, using CNC milled parts or something similar.
In my opine,
The Epicyclic Parson's would be a more viable project.
The video shows a single cylinder, which is easiest test
article, if you or a lurker is sufficiently interested.
Good luck chap.
From what I've read, you can get sufficient heat transfer from a moving liner to the outer piston walls via the oil film if the tolerances are close enough.Sockmonkey:
Interesting concept but would only run for a short period of time as the inner (moving) liner has no cooling path to outer (cooled) liner. Needs actual contact. Also no way to cool the piston unless there is a TON of oil flowing through the "crankcase" area.
Enter your email address to join:
Register today and take advantage of membership benefits.
Enter your email address to join: