Interesting cooling concept.

[dcbrown73]

I had read about this before, but here is a video that shows how it works.

If you keep your wine in a room that is mostly cool, but could benefit from a bit more cooling (especially in warmer months) maybe this is a homemade device you can make without adding another A/C unit.

Though since your house is sealed, you can probably create some type of funnel out of a heavy duty plastic garbage bag duct tapped around a tornado fan leading to the back of the board to force air through the bottle tops.

My house is at 72F. If it's true that you can drop the temperature by up to 5 degrees Celsius. Theoretically, I could drop my wine storage closet closer to 64-65F!

[ame]https://www.youtube.com/watch?v=jPuh8IFbIzQ[/ame]

 

[Boatboy24]

Fascinating!

 

[Mismost]

In those villages...I think if they put a layer of thatch on top of the tin roof it would also help by blocking the sun's radiation from the roof....shading it in effect. Vines planted in front west walls would also help....grape vines of course!

A friend in West Texas has one of those concrete cattle troughs and a wind mill in the pasture...they built a simple brush arbor beside it on the north side...big piece of burlap is hanging up next to the trough and down into the water...south wind blows through the burlap...you're sitting in shade and it's quite a bit cooler with the breeze cooled by that burlap wicking water up from the trough. Nice spot to eat lunch after working cows all morning....if you can stand the flies!

 

[BernardSmith]

What a great idea... but I wonder if it works only when the air is moving at significant velocity (a need for the fan or for there to be an open window and the fixture set up to block it

 

[lilvixen]

That's really neat!

 

[vacuumpumpman]

very simple idea !

I would like to look into it a bit more - a 20 degree F drop is alot

 

[JohnT]

Interesting, but wouldn't it only work in a strong breeze that would cool you off anyway??

 

[dcbrown73]

very simple idea !

I would like to look into it a bit more - a 20 degree F drop is alot

I believe it's closer to 9 degree Fahrenheit. 1 degree Celsius is equal to 1.8 degrees Fahrenheit. (1.8 * 5 = 9)

Which is why I said my 72F wine storage closet, could be brought down to 65F (or 63F if it actually can cool 5 degrees Celsius)

I generally cool my reds to 65F in my counter top wine cooler. I wouldn't have to do that anymore and only keep my whites in it at 55F.

 

[dcbrown73]

Interesting, but wouldn't it only work in a strong breeze that would cool you off anyway??

You would need a breeze strong enough to force air through it.

That's why I said I would get a tornado fan and a heavy duty garbage bag to create a funnel from the fan to the back of the board with the 2 liter bottles in it.

I don't buy 2 liter bottles, but I go through 16.9 ounce water bottles at work. Maybe I will try with those.

 

[bkisel]

Wow! What a cool idea!

In Vietnam we were able to cool our squad tents if able to get a parachute and hang it a foot or so below the canvas top. I've no idea, in degrees, how much cooler it made the tent but I can tell you that it was definitely noticeable compared to squad tents not having a parachute.

 

[JohnT]

It is worth an experiment. It is hard to believe that such a little amount of compression can make such a difference. I was never really big on thermodynamics, but I am sure that someone on this sight can do the math.........

 

[Boatboy24]

Wow! What a cool idea!

I see what you did there!

 

[vacuumpumpman]

I believe it's closer to 9 degree Fahrenheit. 1 degree Celsius is equal to 1.8 degrees Fahrenheit. (1.8 * 5 = 9)

Which is why I said my 72F wine storage closet, could be brought down to 65F (or 63F if it actually can cool 5 degrees Celsius)

I generally cool my reds to 65F in my counter top wine cooler. I wouldn't have to do that anymore and only keep my whites in it at 55F.

I went off the 2 temperature readings in the photo -

 

[stickman]

I have to call BS on this one. In general, as a gas is compressed the temperature of the gas increases. Any cooling caused by the gas dropping in pressure as it flows through the nozzle would be offset by the temperature increase during compression. The air speed may be increased, so it may feel a bit cooler, but the total air flow would be reduced. In sweltering dry heat it may be better than nothing, but I don't think you'll be seeing these things cooling a wine room any time soon.

 

[ibglowin]

Where is the resident WMT Physicist @sour_grapes when we need him...........

 

[terrymck]

It's been over 50 years since I sat in a classroom but I would say that it's not the compression of the air but the expansion after it leave the nozzle that causes the cooling effect. One of those dead Europeans discovered it. Boyle, Pascal someone like that.

 

[dcbrown73]

It's been over 50 years since I sat in a classroom but I would say that it's not the compression of the air but the expansion after it leave the nozzle that causes the cooling effect. One of those dead Europeans discovered it. Boyle, Pascal someone like that.

Thanks Terrymck.

From Wikipedia:

Joule–Thomson effect
The effect is named after James Prescott Joule and William Thomson, 1st Baron Kelvin, who discovered it in 1852.
​

LINK => Why does air cool as it expands?

EDIT: The interesting thing here is, in this case the compression of the air entering into the bottle theoretically should have caused the air to heat up, then cool back down as it left the nozzle. (returning to the same air pressure) How does it end up cooler is the question.

 

[stickman]

Yes, there is cooling when a gas expands, but there is heating when it is compressed. In the picture, air flows into the large end of the bottle and is compressed as it moves into the neck, as it flows out of the neck and into the room it expands, so the temperature of the air is first heated by the compression and then cooled by the expansion; therefore, there is no net change in the air temperature.

 

[richmke]

It is the way an air-conditioner works. The gas is compressed, and heats up. If something can take away the heat, then when it expands, it will be cooler than before.

I don't see how the gas can give up enough heat to the nozzle to make a difference.

 

[Mismost]

I have to call BS on this one. In general, as a gas is compressed the temperature of the gas increases. Any cooling caused by the gas dropping in pressure as it flows through the nozzle would be offset by the temperature increase during compression. The air speed may be increased, so it may feel a bit cooler, but the total air flow would be reduced. In sweltering dry heat it may be better than nothing, but I don't think you'll be seeing these things cooling a wine room any time soon.

I tend to agree. The thing I noticed in the video was the nice new hole cut into the side of the solid tin wall...any air movement is bound to help inside a tin box!