Hole through middle of car. Aero benefits?

[orange4boy]

I realize this sounds like a whacky idea BUT...

Would it work and how much benefit would it give?

I got the idea from this joke CFD by trebuchet03

Best Mod So Far.... Put a Hole Through Your Car




I did a quick 2 minute solve (like the original stuff posted) - just for fun

This would actually be a fairly simple and easily reversible mod for my van if it gave enough of a benefit.

[SVOboy]

Do it! It would be fun just to see, I think

[aerohead]

Yeah,it's pretty whacky.GM actually released an artist's rendering of an COE 18-wheeler in the 1980s,which depicted an enormous hole between the driver's compartment and running gear below,with streamline sections supporting the upper structure.------------ As far as I know,this is as far as it' gone.No claims were made about the concept.So you and Treb are not alone.-------------------------- The twin-boom Tarf,by Taruffi(?) had driver in one boom and running gear in other,and wing-like spars connecting the two,with Cd 0.10 claimed.I think the polar-moment-of -inertia would limit a vehicle like this to the track,where it operated.----------Some solar racers have used this layout but the didn't make it into the winner's circle.------------------------ The design is a shoe-in for donut-shaped motorists.

[orange4boy]

Theoretically though, it would work, correct?

Air from the high pressure region in the front would rush to fill the low pressure in the back with little restriction other than surface friction. I guess it would have to be a pretty direct path. I would think this would be even better if it was the radiator duct but then it would have to be insulated in the summer.

I suppose it wouldn't be a huge change but it's an interesting thought experiment.

[Bicycle Bob]

This might help fix an existing vehicle if the interior room is not needed, but if you pursue the idea, you wind up with a stove pipe with all surface drag and no useful volume.

[cfg83]

Bicycle Bob -

Originally Posted by Bicycle Bob

This might help fix an existing vehicle if the interior room is not needed, but if you pursue the idea, you wind up with a stove pipe with all surface drag and no useful volume.

Would an inline fan help make a smaller diameter pipe useful? For the purpose of the conversation, assume the cost of running the fan is free.

CarloSW2

[Bicycle Bob]

If you can postulate a free fan, you can rewrite the economics of almost anything.

[cfg83]

Bicycle Bob -

Originally Posted by Bicycle Bob

If you can postulate a free fan, you can rewrite the economics of almost anything.

I know, but I want to know if the "aero" will benefit first.

If the system was workable, then you could run the fan off a battery?!?!?!

CarloSW2

[Bicycle Bob]

The aero can benefit to the point the regular engine becomes redundant - just see a jet aircraft. The battery power is not free - it makes the alternator draw power from the engine.

[NeilBlanchard]

Hi,

If this idea was used to ventilate the interior of the car, then it would have that benefit, as well as filling in the low pressure in the back. The Aptera does essentially this exact thing.