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When it comes to an automobile's engine with moving parts..

The engine uses oil to keep things lubricated..Which aids in friction, heat, wear etc..etc..Soooo..Too much friction is a bad thing right?

At what point does too little friction present a problem?

Where you at GM?


Rayo..
 

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probably at the point where it reaches zero friction, and even then the problems would be minor. for instance you would have to perhaps wait for the engine to stop rotating after you shut the key off. in a zero friction engine the compression would act as a spring, and you would have to wait until the spring pressure and the weight of the rotating mass counteracted each other for the engine to stop rotating.

other problems would be acceleration of the engine to higher rpms would be harder to properly control, and you could face a runaway engine situation as there would be virtually nothing holding the engine back. however technology could take care of that.

but if you could create a frictionless engine, imagine the power and fuel economy levels you could reach. add to that the ability to run an engine at 1000 degrees, thats one of the nice things about reducing friction is that engine temps can be hotter before one runs into temperature issues.
 

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but if you could create a frictionless engine, imagine the power and fuel economy levels you could reach. add to that the ability to run an engine at 1000 degrees, thats one of the nice things about reducing friction is that engine temps can be hotter before one runs into temperature issues.
Aside from fuel pre-ignition? :)
 

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At 1000°, what do you make the injector seals out of?

:D

There is no mechanism that I can think of on our cars' engines that requires friction to operate; every point I can image would run cooler, and thus at a lower rate failure.

The transmission requires it.
And it requires it to be precise, and apply and release on command; variations high or low from the baseline cause issues.

Tires and brakes are friction dependent; a good coat of oil will prove that. :)


IDK why, but it made me think of this lyric:

Spontaneous combustion
Scientific fact
But your approach to friction
(is an) An unnatural act
Bells I hear ain't fire drills
I hope you understand
It's a bona fide five alarmer
Melting in my hand

Alice Cooper Muscle of Love :)
 

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If there were no friction,
I think that would be a perpetual motion machine.
 

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If there were no friction,
I think that would be a perpetual motion machine.
+1 :tongue:

It would certainly have the potential to be one.
 

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When it comes to an automobile's engine with moving parts..

The engine uses oil to keep things lubricated..Which aids in friction, heat, wear etc..etc..Soooo..Too much friction is a bad thing right?

At what point does too little friction present a problem?

Where you at GM?


Rayo..
Engine oil doesnt just lubricate, it provides a coushin barrier between parts like the connecting rods / crankshaft.

Newer engines are made for lower viscoscity oils but they require tighter tolerances and well balanced rotating assemblies.
 

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you can never reach zero friction, therefore the less friction is always better. No such thing as a "runaway" engine because even if it were in neutral not connected to the transmission/drivetrain, once you let off the throttle the dashpot function built into the PCM controls idle, regardless at what RPM you just let off the throttle. Even if you could get to astonishingly low levels of friction, the "new" friction will manifest itself in pumping losses via the intake/exhaust tracts, ultimately dictated by the IAC and the dashpot function that control's it's behavior. When you shut the engine off, the opening orifice in the IAC collapses to it's rest state, which is NC (normally closed, just like a relay). Hence the pistons attempting to draw air down the intake ports connected to a closed intake tract will still cause immediate shut down of the engine. Friction or not, you can't draw air across a restrictive orifice without energy. No air/fuel to burn, no energy.

My 2V is as frictionless as it will get for an old mod motor.
 

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He beat me to it. ^^^
 

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you can never reach zero friction, therefore the less friction is always better. No such thing as a "runaway" engine because even if it were in neutral not connected to the transmission/drivetrain, once you let off the throttle the dashpot function built into the PCM controls idle, regardless at what RPM you just let off the throttle. Even if you could get to astonishingly low levels of friction, the "new" friction will manifest itself in pumping losses via the intake/exhaust tracts, ultimately dictated by the IAC and the dashpot function that control's it's behavior. When you shut the engine off, the opening orifice in the IAC collapses to it's rest state, which is NC (normally closed, just like a relay). Hence the pistons attempting to draw air down the intake ports connected to a closed intake tract will still cause immediate shut down of the engine. Friction or not, you can't draw air across a restrictive orifice without energy. No air/fuel to burn, no energy.

My 2V is as frictionless as it will get for an old mod motor.
Except on diesel engines with no throttle body, the rpm is controlled by the amount of fuel you put in.
 

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There are magneticle levitated compressors that have no bearings. They are frictionless, but if levitation fails while running, its a major catastrophic failure. Also now have centrifugal chiller compressors up to 1000 horsepower that have ceramic ball bearings and use no oil. For refrigeration thats huge. They have very little friction.
 

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very little friction is not the same as no friction. The closest thing man has seen to no friction is an electric current in a superconducting loop. I know they say they are "no friction", but unless that thing is spinning in a complete vacuum, there will ALWAYS be friction. Even the tiniest molecules/atoms in the atmosphere cause friction.
 

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The best possible gas flow gauge is a magnetically-levitated ball, spinning at incredible speeds.

Individual gas atoms can be detected, by how much it slows the ball down when it hits. :)

There is no friction on the ball but the residual gases...



Forget friction; I want a knob to crank down inertia!
 

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Discussion Starter #18


Interesting..So how does friction effect fuel mileage?

Friction makes heat..A warmer engine gets better fuel mileage..No?

With less friction..The engine would stay cooler..Taking the thermostat more time to open, and the engine to warm up..

How do you reap the benefits of a low friction engine..As far as fuel mileage is concerned?

Will the ecm keep the engine in "open loop" if it's too cool?



Rayo..
 

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Most of the heat generated by the engine is a by-product of combustion; the heat generated by friction would be practically negligible by comparison...

Effectively, to get less friction and cause less wear on engine components, you need thinner oils. To use such oils, you need tighter clearances...

Most of the "frictions" generated by the engine itself are actually pumping losses. Basically, under high manifold vacuum or a relatively small throttle blade opening, there is comparatively more vacuum generated in each cylinder on the intake stroke. To create this vacuum more energy from the combustion stroke has to go into drawing the air into the cylinders.

One way to combat this is to have less vacuum for a given RPM/throttle setting - commonly achieved by leaning out the mixture a tad so as to create less power, requiring a greater throttle blade opening. This generates a higher load at that RPM than there would be at stoich, translating to less vacuum in the cylinders, less pumping losses, more power transmitted to the wheels, better fuel economy.
 

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Discussion Starter #20
Ok..Thanks..

I know there's plenty of smart people here..So I'd like to hear someone else chime in..

Lets say you found a way to decrease friction in the rotating assembly..So much so that the engine never reached optimal mpg temperature..

If the engine never reached optimal mpg temperature..The car would use more fuel because the ecm would keep it in "open loop"..Right?

What's your guys take on this?



Rayo..
 
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