12-04-2010, 04:28 PM
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#91 (permalink)
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Master EcoModder
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I guess the difference between me an you DCB, is you look for reasons it can't be done, and I know there are reasons it can be done.
Go any contribution to success?
Haven't seen one yet.
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12-04-2010, 04:32 PM
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#92 (permalink)
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Electric motors must be sized for the load applied. Are you going to change your electric motor when you change the load?
That's the only way you will see 93% efficiency as an average, but you use an average efficiency to criticize IC engines when simple driving tactics can double engine efficiency and triple vehicle mileage.
With no changes to the engine itself, just changes in the way it is operated.
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12-04-2010, 04:40 PM
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#93 (permalink)
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Quote:
Originally Posted by NeilBlanchard
The Revetec design doubles the efficiency of a crankshaft design. If some of the other major losses could be addressed, then could the efficiency go above 50%? Is 60% possible?
The major problems with most current ICE designs:
Poor geometric / mechanical torque due to the inherent limitations of the sinusoidal motion of the piston and the connecting rod's angle relative to the crankshaft (vs a rotary design or an electric motor)
No con rods cylinders maintain parallel aspect to the location points at top and bottom, sequential injection pulses to produce peak pressure at best point of leverage.
Long time periods between power strokes, requiring relatively large flywheels.
reduce cycles by 50%
Large mechanical drag from the valvetrain having to work against the springs.
No valve train
The acceleration and deceleration of the piston and connecting rods.
Eliminate it.
The brief / momentary pressure buildup of the fuel burn (vs the constant pressure reserve of a head of steam, for example)
Covered by injection fuel in several events during the combustion stroke.
The need to pump oil through tiny passageways, and to generate electricity.
Actually you can produce oil pressure with less energy than an electric hand drill, but you can reduce the engines total running time by 80% using capacitive storage and release with a IVT of some configuration.
The need to warm up to reach ideal operating temperature.
Eliminate the cylinder head.
The amount of waste heat requires a lot of "stuff" and requires a lot more aerodynamic drag to be able to dump it out of the vehicle.
Insulate everything to reatin the heat and use it to generate power for all of the accessories.
The relatively narrow torque band, requiring a multi-ratio transmission -- basically as many gears as possible. Seven or eight gears would be better than merely three to five.
Operate engine only at peak torque
The need to idle while not actually being used.
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Eliminate idling.
No new technology necessary.
regards
Mech
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12-04-2010, 04:41 PM
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#94 (permalink)
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needs more cowbell
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Dude, don't be defensive, I'm already driving a tdi, which they list as 41% efficient, and drive it more efficiently than most people realize is possible (there are many boxes that bind us).
I did research the hydraulic transmission a bit more, in this real world example it is ~85% efficient.
Torvec, Inc. - Message from the CEO ", reflecting an overall operating efficiency of 85% (92% x 92%). " which isn't real good for long distances. Sprockets are the best I've seen so far, achieving up to 98% transmission efficiency.
You should stop the personal attacks immediately and deal with the technical issues and invalid assumptions you are making.
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WINDMILLS DO NOT WORK THAT WAY!!!
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12-04-2010, 04:52 PM
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#95 (permalink)
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Do some more research, about a decades worth, and you might actually be able to contribute.
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12-04-2010, 04:53 PM
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#96 (permalink)
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The efficiency of electric motors is very flat across a very wide RPM range. For example, the Illuminati Seven has a 5-speed Suzuki/Metro transmission, but they found out that they can run very well in just 3rd or 4th gear. So, they put in 3rd to get more acceleration, or 4th to get more efficiency. Having a continuously variable transmission (even with a narrow range) would help an EV wring out the last bit of efficiency, but the difference is relatively small.
Back on topic, electric motors are a great model to study for efficiency -- much of it comes from the nearly perfect geometry of the force vectors relative to the rotation of the armature.
On the "Blanchard Cycle" proposed open source design, I realized that it has a power stroke (in each pair of cylinders) that is 270 degrees out of every 360 / revolution. Compared to a typical 4-stroke that has only 90 degrees out of every 720 degrees, or every 360 if you have two cylinders. So, from that standpoint, all else being equal, it would be producing 3-6X more torque, and it could be nearly that much more efficient, too.
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12-04-2010, 04:54 PM
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#97 (permalink)
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Quote a single personal attack, while you do little else.
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12-04-2010, 04:56 PM
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#98 (permalink)
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needs more cowbell
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Quote:
Originally Posted by NeilBlanchard
The efficiency of electric motors is very flat across a very wide RPM range.
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that is not the traditional perspective
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12-04-2010, 04:58 PM
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#99 (permalink)
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needs more cowbell
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Quote:
Originally Posted by Old Mechanic
Quote a single personal attack, while you do little else.
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your past 10 posts have all addressed me, even though I have been talking about things other than you.
Look, you said nobody listened, in fact I did. I spent several hours trying to pull out of you the details of what you were trying to say. When I finally got it, I said you gotta do some more testing to verify your claims. Which was really me trying to say in a nice way "I wish I had those several hours of my life back".
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WINDMILLS DO NOT WORK THAT WAY!!!
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12-04-2010, 05:41 PM
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#100 (permalink)
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Old Mechanic -
Quote:
Originally Posted by Old Mechanic
I guess the difference between me an you DCB, is you look for reasons it can't be done, and I know there are reasons it can be done.
Go any contribution to success?
Haven't seen one yet.
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In fairness to dcb, he is the creator of the open-source MPGuino :
OpenGauge / MPGuino FE computer - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com
In fairness to your main project, I think that perfecting a hydraulic drivetrain is not as easily "scalable" to an open-source solution.
CarloSW2
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