Both. I'm building a custom trike out to be an apocalypse vehicle. The next body shell is designed to accommodate solar charging, I'll be able to comfortably sleep in the vehicle, and I'd like to have an ICE converted to run on ethanol or methanol or a diesel. I plan to use the traction battery as an energy source for heat as well as for cooking, and I'll require any onboard ICE to handle those demands without depleting the battery. The pedal drivetrain is also there as a meagre range extender and a last-ditch effort to remain mobile if all else fails, although with all this crap onboard, the unladen ready-to-ride full vehicle will be approaching 150 lbs.
As soon as you you can use the normally wasted heat from an engine the efficiency goes WAY up!
We're talking 90% plus if you use both the exhaust and cooling waste heat.
It changes the ICE picture completely..!
The heat from engine cooling is easy. Maybe even more so with an air cooled engine.
And yes; cooking on engine exhausts is a thing!
Mostly for a novel talking point, but possible.
I think
an important option or feature that hasn't been considered here is that a small genset can be a 'quick release' plug in/out device that can be left at home for shorter 'to work and back' type trips and quickly 'plugged' in for longer trips..!
When you're camped you might unplug it and put it further away = quieter with an extension cord back to you/the velo.
For heat from an air cooled engine flexible vent ducting is light and 'folds up' to a surprisingly small size.
A quick connect tail pipe is a bit of a challenge. You get metal quick connects for air though.
Do give these ideas a think.
I prefer 4-strokes. More efficiency potential and no need to mix oil into the fuel. I have zero concern regarding missions, as the gasoline engine will not be used often, even though the 4 stroke is an improvement in this regard vs the 2 stroke.
Hmmm... Not necessarily:
(An old post of mine)
If a 2-stroke is run at a constant rpm we can get most of the charge that is otherwise lost out the exhaust to return to the combustion chamber, with an Expansion Chamber or Tune-Pipe.
See the animation.
But not all as there will be some dilution in the tune pipe.
If a tiny reed valve is added to the TRANSFER port;
then the first bit of lost to exhaust charge is not charge but air.
The first bit to be lost is the last bit to be returned by the tune pipe.
So any dilution in the tune pipe is more with plain air than charge.
Meaning more to all charge is returned to the cylinder, by the tune-pipe before the exhaust port closes.
ie: in the video that 1st bit of green to escape, which is the last bit of green to be returned is plain air and any dilution is no longer a problem.
There's also a ~30% power increase and a ~12% economy increase.
That makes them worth the space and weight..?
The other place where there is a problem is with the power stroke only being around half a downward stroke, vs a 4-stroke's full stroke, before the exhaust port opens.
This means that there is way less time for a complete and clean burn of all the charge.
If you were to add hydrogen; the burn is speeded up dramatically, making that initial exhaust escaping down the pipe cleaner.
Here some sort of onboard hydrogen or HHO/Hydroxy cell could be used.
NOT for economy unless its running of a home charged battery, but if you want to improve emissions...
( MIT etc's 'forgotten' plasmatrons are in fact efficient at onboard hydrogen production!)
That leaves the lubricating oil and soot as an issue.
They are MUCH heavier than the gasses in the exhaust.
So a centrifuge after the tune-pipe would be efficient at separating these particulates in the exhaust from the gasses, whence they could be returned to the intake.
( I suspect a centrifuge may also be a very effective muffler. Especially with some thought in that direction put into it's design)
But ye; I doubt there's that much space to play in?
Rotary?
If the seals last?
pmc.ncbi.nlm.nih.gov
link.springer.com
toyanengine.com
endless-sphere.com
www.liquidpiston.com
