pusher fan for small SUV

[H-Man]

You know what? Forget the SUV. Give me that dang flying car.

[mort]

Originally Posted by ChazInMT

His assumption is that somehow a fan is better at converting gasoline into thrust, if this were the case, we'd all have propeller cars. There's no magic in a propeller, a fan would simply not be more efficient at converting gasoline into usable thrust than turning the tires with a drive shaft.

I agree, but there are other reasons for not having propeller cars, the prop would be big and there would be safety and noise issues.
This isn't a pure slam-dunk. Good propellers are about 85% efficient, compared to 90 to 95% efficient gears and tires drive train - so it doesn't look that bad. Only going to waste a little gas.
-mort

[ChazInMT]

Originally Posted by mort

This isn't a pure slam-dunk. Good propellers are about 85% efficient, compared to 90 to 95% efficient gears and tires drive train - so it doesn't look that bad. Only going to waste a little gas.
-mort

If by a little gas you mean I'd only get 31MPG with my car as opposed to 35MPG I suppose you're right. And that assumes a perfect propeller design and implementation....something a home built Briggs and Stratton motor with a "who knows the source" propeller is unlikely to yield.

And don't even get me started on the aerodynamic aspect of something sticking up on a vehicle that is at least 2 square feet of added frontal area.

This isn't the worst idea ever, it just really does not pen out at all in being able to improve what is the current drive train.

[baldlobo]

i think he means to build one of these

[ChazInMT]

Originally Posted by baldlobo

i think he means to build one of these

Oh, all right then, forget everything I said and carry on straight away.

What was I thinking.

[baldlobo]

http://www.darkroastedblend.com/2008...essential.html

[redneck]

Originally Posted by baldlobo

http://www.darkroastedblend.com/2008...essential.html

That was a excellent link.

Thanks for posting...

>

[gone-ot]

...loved the blue/white "Rock-n-Roll" Messerschmitt(?) conversion:

[jamesqf]

I think he's talking about something like an airboat Airboat - Wikipedia, the free encyclopedia that's used in swampy waterways where a water prop would be fouled. I don't think they're really efficient, as they use a small aircraft engine to attain the sort of speeds you'd get from a much smaller outboard. And I really like the Wikipedia article's understated comment:

The engine and propeller are enclosed in a protective metal cage that prevents objects, e.g., tree limbs, branches, clothing, beverage containers, passengers, or wildlife, from coming in contact with the whirling propeller...

PS: Just a note re small aircraft efficiency. With my Piper Cherokee 180, I could do about 18 mpg, not far off typical SUV mileage, but I was travelling at ~140 mph, and often cutting miles travelled by a third, or even half, 'cause I didn't have to go around curves.

[ChazInMT]

Originally Posted by jamesqf

PS: Just a note re small aircraft efficiency. With my Piper Cherokee 180, I could do about 18 mpg, not far off typical SUV mileage, but I was travelling at ~140 mph, and often cutting miles travelled by a third, or even half, 'cause I didn't have to go around curves.

Flew a Warrior when I took lessons a few years back, so I like flying. You do realize that you were getting 18mpg in what is essentially my Civic while doing 140 mph. Fun, yes....Fast, you betcha..... beautiful view, Oh Man....worth every penny, certainly....efficient, debatable.