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wmjinman · 03-28-2013, 03:09 PM

I think Diesel Dave is joking with that picture. Look at all the single cylinder lawn mowers, generators, and such. They undoubtedly have heavier flywheels in relation to their size, but not comical proportions like in this picture.

I'm not sure if that's a steam engine or not, but it made me think of steam (I kinda have a "thing" for steam). But with pehaps not much more effort than your cylinder deactivation idea, a "steam-o-lene" design like Bruce Crower of Crower Cams came up with intrigues me.

What he does is has a special cam with additional lobes (convenient he's a cam manufacturer, huh?) that open the exhaust valves again, making it a 6-stroke engine instead of 4-stroke. Then there's an injector that squirts some water in at the start of the 5th stroke, which is the second power stroke - a STEAM power stroke.

So the engine goes like this:

> 1st stroke: Intake - intake valves open, piston moves down drawing in intake "charge"
> 2nd stroke: Compression - all valves closed piston moves up, compressing charge
> 3rd stroke: Power - all valves closed spark plug fires, fuel burn drives piston down
> 4th stroke: Exhaust - exhaust valves open, piston moves up, pumping exhaust out.

That's where a "regular" engine goes back to stroke 1, "intake". But in Crower's design, you get:

> 5th stroke: steam power - water is injected near TDC and heat causes steam, driving piston down again
> 6th stroke: steam exhaust - exhaust valve opens again due to 2nd cam lobe, piston moves up, pumping steam out.

And then you go back to stroke 1, Intake.

We always talk about all the waste heat in an internal combusion engine. This scheme uses the heat to make steam and more power. Cooling system could possibly be eliminated altogether. Imagine the "aero" possibilities if you didn't have a radiator you needed to get air to all the time!!!

Bruce calculated the potential efficiency improvement with his design, and it was substantial. Just going off my poor memory, it was something like 25% improvement in gas engines and even more - I wanna say 40% - in diesels!!! Patent pending, I believe...

03-28-2013, 03:09 PM	#16 (permalink)
wmjinman Master EcoModder Join Date: Oct 2012 Location: Carson City, Nevada Posts: 612 Jimmy - '00 GMC Jimmy SLT 90 day: 21.18 mpg (US) The White Gnat - '99 Suzuki Swift Team Suzuki 90 day: 51.87 mpg (US) Thanks: 240 Thanked 114 Times in 90 Posts	I think Diesel Dave is joking with that picture. Look at all the single cylinder lawn mowers, generators, and such. They undoubtedly have heavier flywheels in relation to their size, but not comical proportions like in this picture. I'm not sure if that's a steam engine or not, but it made me think of steam (I kinda have a "thing" for steam). But with pehaps not much more effort than your cylinder deactivation idea, a "steam-o-lene" design like Bruce Crower of Crower Cams came up with intrigues me. What he does is has a special cam with additional lobes (convenient he's a cam manufacturer, huh?) that open the exhaust valves again, making it a 6-stroke engine instead of 4-stroke. Then there's an injector that squirts some water in at the start of the 5th stroke, which is the second power stroke - a STEAM power stroke. So the engine goes like this: > 1st stroke: Intake - intake valves open, piston moves down drawing in intake "charge" > 2nd stroke: Compression - all valves closed piston moves up, compressing charge > 3rd stroke: Power - all valves closed spark plug fires, fuel burn drives piston down > 4th stroke: Exhaust - exhaust valves open, piston moves up, pumping exhaust out. That's where a "regular" engine goes back to stroke 1, "intake". But in Crower's design, you get: > 5th stroke: steam power - water is injected near TDC and heat causes steam, driving piston down again > 6th stroke: steam exhaust - exhaust valve opens again due to 2nd cam lobe, piston moves up, pumping steam out. And then you go back to stroke 1, Intake. We always talk about all the waste heat in an internal combusion engine. This scheme uses the heat to make steam and more power. Cooling system could possibly be eliminated altogether. Imagine the "aero" possibilities if you didn't have a radiator you needed to get air to all the time!!! Bruce calculated the potential efficiency improvement with his design, and it was substantial. Just going off my poor memory, it was something like 25% improvement in gas engines and even more - I wanna say 40% - in diesels!!! Patent pending, I believe...