I agree with you, It definitely doesn't make sense how it would increase efficiency. But there coast down test showed a 50% increase in coasting time, so maybe that is where the increased efficiency comes from
The Prius is arguably one of the most fuel efficient cars available, and is far more quiet than most.
[Edited by poster to correct silly writing]
Do electronic [fuel injection] and the related computer control unit increase noise, vibration and harshness? I think it's generally agreed that elec. [fuel injection] is more efficient overall than carburetors. And that's without considering how carbs misbehave when they get dirty/leaky/out of adjustment.
Last edited by brucepick; 10-29-2011 at 10:16 PM..
in my opinion, quiet=efficiency. That means that the air is flowing smooth over the vehicle. But noise is probably one of the worst ways to judge efficiency
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When I refer to noise, it is generally in relation to sound deadening; road noise; and engine sounds. Softer engine mounts and bushings mean less noise, but it also means that energy that could have driven the car forward was absorbed. Obviously, electric cars are much different than ICE, but many of the concepts translate well.
Do electronic ignition and the related computer control unit increase noise, vibration and harshness? I think it's generally agreed that elec. ign. is more efficient overall than carburetors. And that's without considering how carbs misbehave when they get dirty/leaky/out of adjustment.
If what ERW says it true, than michelin will not be able to sell their tweel because ERW has the patents. It's too bad because michelin is the one with all the money to get a product to market.
Michelin has their own patents. It looks like this company worked around Michelin's patents using bolts then obtained their own patent going that route.
I would be very hesitant about these wheels/tires as one good pot hole at highway speed would do them in just like it will do in low profile rims.
They are working on updated prototypes, and they have a version that has a closed "tire".
They are using a direct method of measuring rolling resistance -- a dynamometer. And quiet can be from dampening, which could also be causing higher rolling resistance.
This sort of tire seems to me to be able to provide lower rolling resistance; and I'm glad that someone is trying to develop this. The Tweel is non-pneumatic but it is designed to flex just like a pneumatic tire so that it can be used with the same suspension as standard tires.
I think that a more rigid wheel could provide lower rolling resistance, and that if the suspension was reworked to provide a smooth ride, that the combination would be more efficient and just as comfortable a ride. And if the suspension was regenerative, like the Levant Power shocks are, then this would provide more regenerated power than it would with pneumatic tires. The end result in theory, would be a more efficient vehicle, with more regenerative power and just as good or better ride; that would not require regular air pressure checks, and would not have punctures or blowouts.
With a car with full wheel skirts, like the Edison2 VLC or the Aptera or my CarBEN EV5, not having to check air pressure and not having to worry about changing a wheel on the side of the road would be a really good thing.
So, this type of technical development is a very good thing. Someone should be doing it. I would love to try these on CarBEN EV5 with regenerative shocks; after I get a working prototype built with standard tires.
To me, I think hydraulic energy recapture is the best way to go when talking about efficient tires. Mate a very efficient, hard tire with very good (computer controlled) suspension that can capture some of the bump energy and use it for forward propulsion.
I don't know much about tires, but I'd worry about harmonics with a tire/wheel like this. It seems like (in the right situation) this wheel could act like a car with springs but no dampers.
Right, the regenerative shocks that Levant make are hydraulic, with a small turbine and a generator as the load/dampener, and it can be used to vary the dampening, but this uses some power. If it is just used as "passive" dampening like a standard shock, then it would generate power to charge the battery.
Large truck tires -- mudders and oversized offroad tires have this undamped spring issue.