Many tunnels go through mountains. Mountains typically have a big static air pressure differential due to wind systems obstructed by the mountain.

My tunnel would be divided into two separate tunnels (opposing lanes). One heading up the pressure gradient would be unassisted, and the other assisted.

On the upwind side, a position in the mountain would be chosen that funnelled and concentrated the wind and this would be blown down the tunnel at around 30mph.

This would reduce fuel consumption of vehicles in the 'assisted' tunnel. The unassisted tunnel would be designed so that baffles, etc. reduced the contraflow of wind in that side.

PS, I have already considered a closed loop system but that would lead to a build up of exhaust fumes.
-- FloridaManatee, Jun 18 2003

(?) Bicycle Version http://www.biketrans.com/info.html
Near-Baked for bicycles [bicyclist23, Oct 05 2004, last modified Oct 21 2004]

<constructs sail from shirt and folding jack-handle, extends sail from sun-roof>
-- lurch, Jun 19 2003


What would the maximum wind velocity be? I remember from school a walkway where the wind would be concentrated, and on some days it was strong enough to knock people over. Surely variable weather conditions would cause similar problems.

That is unless you installed variable baffles at the assisted tunnel entrance. (New problem - tunnel closed due to excessive wind.)
-- suctionpad, Jun 19 2003


use a closed system with a car 'container' similar to the ones at bank drive throughs. as you approach the tunnel, a door opens, you drive into the container, you stop your car, the door closes, a vacuum sucks your container, and zips you to the other end where another door opens and you drive out. sounds like fun ;)
-- gooeythoughts, Jun 19 2003


I'll bite. [+]
-- oxen crossing, Jun 19 2003


[suctionpad], you're right, the velocity would have to be moderated. The idea is not to have so much wind flow that it's propelling cars down the tunnel, but enough to improve fuel economy.

My idea was that the tunnel should be designed so that peak flow without traffic should be 50-70mph, but I agree that your idea with variable baffles adds value.
-- FloridaManatee, Jun 20 2003


A definate plus but you will have to move if you want to see your plans come to fruition.
-- sartep, Jun 20 2003


wind energy potential relates to the cube of the wind velocity. That ultimately means your equipment is trading dollars for pesos in what it is trying to accomplish.
-- MrExergy, Nov 04 2017



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