Cooling a 64Ft Parachute Dome

[Shurafaliminal]

We are building a Parachute Dome for the first time this year. I noticed that some people like to put a second parachute in the dome to help block the sun. Does anyone have any experience with this? Any tips, thoughts, suggestions would be much appreciated!

[MrBeardy]

I've got a 16 foot dome and i do the parachute as well on it with several sheets and blankets under it, mostly to prevent the parachute from billowing. With a dome of your magnitude a swamp cooler is out of the question I think and likely instead you will want a way to raise and lower the bottom part of it to allow wind to pass through as well as maintaining the opening at the top for heat to escape. Best of luck and let us know how your planning and results turn out!

[GreyCoyote]

At 68,000 cu/ft of enclosed space, you are looking at a LOT of cooling. You would need one complete air change every two minutes as a bare minimum, and that translates to at least five of the big 6,000 cfm evap coolers. Thats a lot of power and water right there. But it could be done. Or concentrate on spot-cooling. Create small zones where the temp is lowered. People can move in and out as they need it.

In the long run hiwever, I think Mr. B hit the nail squarely on the head: leave a 2-3 foot gap on the sides, and have an open top. Shade and convection are your friend. If you want to encourage the flow, put a big exhaust fan up on top to get the heat out of the dome. This is what we do on ours, and it works very well. On a dome your size, a 10,000 cfm industrial fan would work and wouldnt break the bank. Look in ag stores as these are used for livestock cooling.

Finally, consider a mist system inside the dome perimeter so air entering is cooled and humidified. Done properly, this could be VERY effective and relatively cheap.

Good luck! Cant wait to see this in the dust!

[Shurafaliminal]

Thank you for the insights. Much appreciated!

Anyone have any recommendations for a good secondary parachute we can use to diffuse the sunlight?

[whimsicaltoast]

Thanks for the helpful question AND the responses here! We have ~4.5 ft open bottoms to let the air through our dome, but no top air vent... perhaps that would make the difference. Not sure we have enough time to implement it this year, but these are great things to keep in mind!

We're also thinking about playing with having one side of the parachute side being covered in aluminet for extra shading/protection, but I'm unsure how that will work out, as I think our plan is to "figure it out" on the playa, haha.

Do keep us updated on how things work out, if you're able to find a 2nd parachute/etc!

[gaminwench]

FWIW, parachutes are not UV protective; you get shade, but no sunscreen protection. Adding Aluminet would counter this.

[sharpstick]

translucent parachute makes for a great greenhouse, and is hard to fasten down because it doesn't fight tightly to anything.

[Token]

I love giant solar ovens.

Y'all will bake all week long.

Go look up pictures of large domes from years past. Only cover the sun side for shade, leave rest open.

Parachute is the worst choice for dome cover.

[sharpstick]

FWIW, parachutes are not UV protective; you get shade, but no sunscreen protection. Adding Aluminet would counter this.

Generally, parachutes are one big greenhouse unless you line it with a completely opaque inner layer.

[Papa Bear]

Parachutes can work, but not by themselves.

Your best bet (assuming you are going with the chute idea) is a second layer suspended at least 12 inches below the outer one, so that the air gap absorbs most of the heat and the warm air can flow up and out the hole in the center. You'll also want to keep the sides open at the base to allow the breeze to flow through.

That second layer can be a simple as another parachute (the difference will be noticeable), but I'd imagine the more opaque or reflective it is, the better. Though if you have something like that, the smarter idea might be to put it on the outside, and use the chute as the inner layer with a gap.

[Papa Bear]

Whoops, just noticed that this is an old thread. Ah well, maybe someone will find it useful.