Artificial Wind to Move away Urban Air Pollution 6

[McDermott1711]

Hi everybody,
I don't know is here a proper place for this thread, but let me a try!
These days we hear (due to cold weather in northern hemisphere), that some cities challenge polluted environment. I thought, for ages, that what about generating with, say, spreading crashed "white" stones in one side of the city and "black" ones on the other side. Then by shining sun over these areas, we have different temperature in two opposite area, that eventually generate wind, in an "artificial natural" way.
What's your opinion?

 

[gruntguru]

Sounds like a good idea.

Instead of black stones, perhaps a solar PV farm (more than 80% of the sunlight ends up as heat) or a power station? Maybe you could keep all the traffic on one side of the city?

je suis charlie

 

[BUGGAR]

Unless the pollution is so bad (Beijing) that the sunlight never reaches the rocks.

 

[IRstuff]

Los Angeles is essentially like that already, but that doesn't eliminate the smog. LA's configuration is orders of magnitude larger than anything that could be man-made.

TTFN
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[JohnRBaker]

Perhaps, but the coastal mountain range blocks much of that natural air flow, except of course when the Santa Ana winds are blowing, which clears the air out quite nicely thank you. And BTW, some of what many people assume is 'smog' in the LA basin is a natural haze that was here long before industry and automobiles as evidenced in some early photographs taken in the area.

John R. Baker, P.E.
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[ornerynorsk]

This may be as simple as holding political conventions in auspicious locations.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[IRstuff]

If it's not mountains, there's always something else. The OP's suggestion is like my gardener blowing all my fallen leaves onto my neighbor's yard. Blowing all of LA's smog into Palmdale/Victorville is not going to go over very well, although LA still seems to have a death grip on Owen's Valley.

I considered the Santa Anas, but they don't really do much except to store it offshore until the winds die down. And, it takes a thermal system about 200 miles across to generate the Santa Ana winds. Crank the math on that, and you're looking nuclear bomb scale energy levels.


So, it takes a boatload of energy, pisses off other people, and doesn't eliminate the smog, just moves it somewhere else.

TTFN
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[SnTMan]

White stones on one side, black on the other, a windfarm in between

Regards,

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[zeusfaber]

And expect the pollutants to rain out downwind.

A.

 

[Sparweb]

The thermals over the black rock side would be impressive, too. I could launch a glider with minimal towing from an airport in the middle of the black rocks, rise up, cruise over the city...
The guy with the landing strip in the white rocks would probably jack up the landing fee. But he'll die of emphyzema in a few years so it's no big deal.
Hmmm How would I get my glider back to the other side? Trailer it back through traffic?
Maybe the rocks could be painted black on one side and white on the other. Flip all of the rocks over and the thermals will lift me back over to the other side of town!

STF

 

[SnTMan]

Well, mind the turbines

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[McDermott1711]

Thanks a lot for participation. Actually, I expected a more technical discussion. Anyway, does anybody know of any software to model and analyze this, considering major parameters such as buildings, mountain, heat from cars, ....?

 

[JohnRBaker]

Perhaps something along these lines, software that combines Thermal and Fluid-Flow analysis:

http://www.plm.automation.siemens.c...-Systems-Cooling-Fact-Sheet-10652&docType=pdf

John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Digital Factory
Cypress, CA
Siemens PLM:
UG/NX Museum:

To an Engineer, the glass is twice as big as it needs to be.

 

[dgallup]

Pretty sure the National Weather service has models.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

 

[McDermott1711]

What's the relation between shinning (duration, angle, color of object,...) and temperature? How this temperature results to different pressure?

 

[KENAT]

"How this temperature results to different pressure? "

https://en.wikipedia.org/wiki/Gay–Lussac_law

https://en.wikipedia.org/wiki/Combined_gas_law

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[dvd]

Instead of making artificial wind, how about making clean air with pollution controls?

 

[flash3780]

Maybe you could put a bunch of solar updraft towers on the hot side:

https://en.wikipedia.org/wiki/Solar_updraft_tower

Unfortunately, a lot of this solar stuff predicates itself on land being cheap. That's not usually the case near cities.

Roof solar collectors work because you're just using the space you already have. Most solar farms find themselves hundreds of miles away from the point of use where land is cheap, and you live with the transmission losses. But, that's neither here nor there.

I'd be interested in how you model it. I think that you could make a pretty simple 2D CFD model to get a rough idea of the flow rates for a given temperature delta. OpenFOAM could probably do it.