tolojim said:
OK, everyone. All engineers here now agree with the above feedback regarding no efficiency losses related to a piston's changing inertia in conventional reciprocating engines. Thank you for your input. But as you'll see, a piston that does not reciprocate is not a "self contradiction".
Just a quick, down and dirty website to view what we've been talking about here.
Please go to
www.circlecycleengine.com
Any and all comments are welcome. See any muck in this brass?
While it's a very interesting idea, there are several problems with the overall idea that I see... Most of all, I don't really think you have removed "reciprocation" in its most general sense from the engine, you've added more! But, that's neither here nor there... from what I see in the animation, some BIG problems with the idea:
1) Lubrication. Not only will it be very difficult to lubricate all of the parts, it will be nearly impossible to lubricate the cylinder without burning off all of your lube each stroke. If you thought 2-stokes or wankels burned a lot of oil, you ain't seen nothing yet. And don't forget, burning the oil will kill your emissions. This engine would be one gas and oil slingin' machine.
2) Compression: It will be very difficult to achieve a good seal with a piston that is completely removed from the cylinder on EACH stroke, and any non-metallic materials these are made out of will have generally poor wear characteristics. This is a problem for people trying to make ceramic reciprocating engines. Also, friction on the seal around the piston from constantly exiting/entering the cylinder will severly increase wear, obviously degrading engine life significantly.
3) Emissions Control: You will not be able to even marginally separate intake and exhaust gases (since they are mixed in the same area), making intake of clean air for combustion nearly impossible, and emissions will be horrible since a catylitic converter will not be possible. It's stated that the cylinders will be completely air cooled, which means they will need large heatsinks on them, making them far larger than presented in the animation.
4) Sound deadening: If you ever get the engine to run it will sound like a shotgun going off each time a cylinder finishes its power stroke, as you have no possiblity of muffling short of encasing the entire engine. Encasing the entire engine to add sound deadening would add significant weight and size to the design, as well as make it even more unlikely you will be able to get clean air into the engine each stroke, and destroy any chances of your "efficient" air cooling.
5) Control: How do you plan to attach fuel lines or plug wires to a cylinder which is constantly rotating? The plugs, wires, and fuel injectors will have to spin WITH the cylinder, increasing rotating mass. I don't think there are any fuel lines or plug wires that would be able to withstand the centripetal accelerations of a couple of thousand rpm's while remaining functional and lasting for many hundreds of hours of operation.
6) Size/Cost/Weight: The added structure that would be required to hold this thing together with the strength needed would be large and heavy, unless made out of more expensive materials. In fact, the total size of this engine would easily surpass a comparable IC engine.
That's just off the top of my head, I'm sure I'll think of many more problems later on this evening. This is a very unique and innovative design, but I think if you want to remove reciprocation from the automotive engine, you need to develop a turbine engine.
