Ram Air Wind Alternator

[Jay2TheRescue]

Hmmm, old thread here but I'll add my 2 cents worth. Modifying a turbo to power an alternator and a/c would create exhaust backpressure which would be a drag on the engine, maybe even more than just leaving the stock setup of being turned by a belt attached to the main drive pulley.

[theholycow]

Welcome, FX Flyboy. I have to say, since you've commanded me in your avatar:

I shall do so. Seriously...I'd be doing it anyway. It's what I'm really good at.

Anyway, note that you've responded to a two-year-old thread. Many or most of the users involved are no longer participating.

[trautotuning]

Just one quick question to this old thread.

How would a turbine, behind the bumper, be of any added aerodynamic drag??

Its behind everything, and the radiator would still get air since air goes past the blades (just at a slower speed obviously).

I have thought deeply of doing this and see absolutley no bad things coming out of it. It its behind the front bumper it is not going to create more drag, take away air from the radiator (like a grill block would), and it will provide free energy... so?!?!

[GasSavers_JoeBob]

Originally Posted by trautotuning

Just one quick question to this old thread.

How would a turbine, behind the bumper, be of any added aerodynamic drag??

Its behind everything, and the radiator would still get air since air goes past the blades (just at a slower speed obviously).

I have thought deeply of doing this and see absolutley no bad things coming out of it. It its behind the front bumper it is not going to create more drag, take away air from the radiator (like a grill block would), and it will provide free energy... so?!?!

Anytime you have air moving over the car, drag is created. Any time it is passing through a hole in a car, more drag is created. If that air is meeting some resistance in that hole (such as that created by a wind turbine), more drag is created.

An air dam on the front of a car would create more drag than a car with no air dam. I'm pretty sure that the mileage gain comes from deflecting the air which would otherwise pass over the uneven surfaces of the underside of the car, which has more drag than the air dam. (Someone correct me if I am wrong).

Here's one way of doing it...combination charging system, rotating air dam and gyroscopic speed governor:




For the real story behind the picture, click on the link below:
http://www.otherpower.com/otherpower...odelAtest.html

[trautotuning]

Originally Posted by JoeBob

Anytime you have air moving over the car, drag is created. Any time it is passing through a hole in a car, more drag is created. If that air is meeting some resistance in that hole (such as that created by a wind turbine), more drag is created.

Sure, but there is already so much drag in the grill that it would not make a difference at all.

There is the hood latch, the radiator, ac stuff, and well... the engine! So another object (and one that actually allows air to flow through it) would be insignificant to aerodynamics but very helpful in supplementing the alternator...

[GasSavers_JoeBob]

I still think there would be drag equivalent to the amount of power the alternator would use, but I could be wrong...give it a try and let us know...

[theholycow]

IMO, if it's somewhere that it's not going to create significant drag, it's also not going to get enough energy into it to make significant electricity.

I really doubt that it could work, but I'd be interested to see you try and find out what your results are.

[KitCarlsonEMS]

Here is an alternator test for you. Rig up an alternator to a bicycle. The easiest way is a small bike with the rear tire removed and a belt to run an alternator connected to the stationary platform. Use it to power a headlight. Wire light with "on-off" switch. Get on and pedal, now turn on the light. See how long you can keep the light going.

30 years ago I used this generator as a part of an "Energy Talk" with school children. Even the most energetic child, would last only a minute.

Electricity is rarely free. Education in physics is priceless!

[theholycow]

What kind of headlight was it? A lightweight human on a bicycle puts out 165 watts at 20mph on flat land.

*WARNING: Taking thread onto a tangent....*

Hmm...I got that number from http://en.wikipedia.org/wiki/Bicycle_performance and actually, there's some interesting measurements in there:

For example, assuming no wind, one gets the following results for kilocalories required and power delivered to the pedals (watts):
175W for a 90 kg bike + rider to go 9m/s (20 mph or 32 km/h) on the flats (76% of effort to overcome aerodynamic drag), or 2.6m/s (5.8 mph or 9.4 km/h) on a 7% grade (21% of effort to overcome aerodynamic drag).
300W for a 90 kg bike + rider at 11m/s (25 mph or 40 km/h) on the flats (83% of effort to overcome aerodynamic drag) or 4.3m/s (9.5 mph or 15 km/h) on a 7% grade (42% of effort to overcome aerodynamic drag).
165W for a 65 kg bike + rider to go 9m/s (20 mph or 32 km/h) on the flats (82% of effort to overcome aerodynamic drag), or 3.3m/s (7.4 mph or 12 km/h) on a 7% grade (37% of effort to overcome aerodynamic drag).
285W for a 65 kg bike + rider at 11m/s (25 mph or 40 km/h) on the flats (87% of effort to overcome aerodynamic drag) or 5.3m/s (12 mph or 19 km/h) on a 7% grade (61% of effort to overcome aerodynamic drag).

Knock 30% of the weight off and only save 6% of the power requirement at 20mph; savings drops to 5% at 25mph. I wonder what the numbers are for a car driving 40mph or 70mph...

[thornburg]

(Continuing the tangent)

Originally Posted by theholycow

Knock 30% of the weight off and only save 6% of the power requirement at 20mph; savings drops to 5% at 25mph. I wonder what the numbers are for a car driving 40mph or 70mph...

I've often wondered about this. Any of us who have read the requisite links on this site are aware that weight reduction of an existing vehicle does yield any substantial measurable gains in FE, until it gets extreme (i.e. a 10% weight reduction (would be about 260lbs off my car) doesn't yeild more than about .5% gain in FE, if that much, but a 40% weight reduction (would be about 1000lbs off my car) yeild substanital measurable gains in FE, especially when combined with other efforts (aero, etc)).

This is where my thoughts have been going:

Many people here are serious about lightweight wheels as a way to increase FE. But since rotating wheels are rather like a flywheel, doesn't that mean that would increase FE during acceleration, but decrease it during steady cruise or glide type operation? I'm thinking mostly in relation to "performance" or "racing" flywheels available as performance mods to cars. Lightweight flywheels increase acceleration, but they also don't hold energy, so as soon as you let off the gas you are basically "back to zero".

Given the reports people give that P&G works better with a moderate throttle (or even wide throttle) than feathering the throttle, and the same goes for what I might call "Pulse and Cruise". It seems generally reported that moderate throttle is better than very light throttle.

Doesn't the combination of these mean that heavier wheels (or even a heavier flywheel) would increase FE for P&G or cruise type driving, but decrease it for heavy city traffic (or other no-cruise driving)?