How to Cool a sealed 10 gallon container?

[Stone]

Hi Everyone

I need some cooling ideas.

I have a Synology NAS that I use for storing my Data. It is a great device but very pricey.

I live 50 meters from the sea which means everything rusts! For example, my TV never lasts longer than 2 years before the corrosion kills it. I gave up trying to have a decent sound amp, they die in 18 months or less. There are no nudists on our beaches because everything that sticks out, rusts, and falls off.

I need to protect the Synology from rust. To do this I bought a plastic container that has a nice airproof sealing lid and placed the Synology inside, the cables running to it through sealed holes.

I have placed some Daubrite VCi rust inhibitors, as well as silicone desiccators in the box. These helps prevent rust formation on the electronic components. I would like to recirculate and slightly cool the air in the box to keep it from overheating. It must recirculate so I do not lose the VCi rust inhibitor concentration or bring in external moist air.

I have no idea how to do this. Of course, budget is always a problem.

The box size is 52 x 37 x26 cm = 38.5 litres

The box size is 20.5 x 14.5 x 10.2 inch = 10.2 gallon

A miniature Air-to-Air Heat Exchanger would be ideal, wonder if they are available?


Anyone suggestions on how I could cool the inside of my sealed container would be appreciated.

 

[TonyM]

You could cool using the workings of a small benchtop type refrigerator.

 

[rhitee93]

They sell various devices for cooling industrial electrical enclosures where it is important to isolate what's inside the cabinet from the atmosphere outside. For the size range you are taking about, I would look into the Peltier (Sometimes called "Thermoelectric Effect") type units.

 

[ninefinger]

Any active cooling solution is going to cost capital upfront, a fair bit of design time if not buying a commercial unit, and operating cost (electricity) over time. Peltier coolers are nice and compact but power hungry little things, using about as many watts as they cool (i.e. to provide ~20Watts cooling capacity you need to supply ~20 watts power to the cooler, so its cooling ~20W one side and heating ~40W the other side).

Perhaps better plan would be to design for passive cooling. A taller container with a simple heat sink at the top may be all that is needed for convection cooling, depending on your requirements (i.e. desired ambient temperature inside enclosure, temperature outside the enclosure, amount of heat to be dissipated, etc.).

I'd go looking on forums that deal with PC's for more ideas. I'm sure someone has done an environmentally sealed PC before that would provide some ideas.

Otherwise, if you're interested in a complicated, home brew suggestion that fits in with model engine making I can suggest a rather more complicated model engine driven recirculating fluid setup with a pump, multiple fans and radiators...

 

[cds4byu]

How much power does your NAS use? That's the first thing we need to know to get a feasible design. Second what is your ambient temperature?

 

[Stone]

Thanks for the replies.
Ambient temp = 15(winter) to 31 degree (summer) Celsius
60W power consumption

 

[Stone]

With open lid, an internal box temp of 25° C will result in a HDD's temps of about 37° C.
When lid is closed, the internal of box temp slowly climes and when it reaches around 35° C the HDD's reach 50° C.
HDD's will die sooner running at 50° C or over. The NAS has 8 x 14TB HDD drives that cost a fortune, so I need them to stay between 40° to 50° C as much as possible.

 

[cobra]

https://www.theverge.com/2020/9/14/...-center-server-underwater-cooling-reliability

 

[ajoeiam]

With open lid, an internal box temp of 25° C will result in a HDD's temps of about 37° C.
When lid is closed, the internal of box temp slowly climes and when it reaches around 35° C the HDD's reach 50° C.
HDD's will die sooner running at 50° C or over. The NAS has 8 x 14TB HDD drives that cost a fortune, so I need them to stay between 40° to 50° C as much as possible.

Dunno if you can but install a Noctua fan inside that case.

I specd my computer, bought in 2011, with maximum cooling capabilities of the time.
I have had to replace fans but am still running the system and it operates well.

Even at house temperature of close to 30C my temperature monitors tell me I rarely get to even 52C.
The longevity of the box tells me things are working as expected.

(Why Noctua - - - quietest and largest amount of air moving fan available AFAIK today.)

 

[kf2qd]

Peltier Devices. check this site out - Peltier - Thermoelectric Cooler Modules - TE Tech Products

 

[cds4byu]

Here's a listing for a 10" x 12" aluminum heat sink. $109. Has a thermal resistance of 0.21C/W, which means that if it is mounted vertically into the side of your box, it can dissipate 60W with a 12 degree temperature rise using only natural (free) convection. Unfortunately, this doesn't work with your ambient of 31 degrees. Even if you used 2 of them you'd have a 6 degree rise, and an internal temperature of 37C which would get you over your desired HD temp of 50C. If you could fit 4 of them in your box, you'd only have a 3 degree rise, and that would meet your requirements.

If you used an external fan to blow on the heat sink, your temperatures would be lower, but I'm not sure how much. You're getting very close to zero temperature difference.

But an advantage to this approach is that it doesn't need any power, except in the hottest times.

 

[Joe Mantle]

Around work on control panels we use what basically is an aluminum plate finned on both sides with muffinsfans blowing on both sides (one inside and one outside) they do a great job keeping nasty stuff out & keeping temperature inside close to ambient outside. Should work good for what you're trying to do & could be put together for on a budget.

 

[awake]

One issue with the suggestion of an aluminum heat sink, with or without fans, is having to mount that heat sink in such a way that it replaces all or part of a wall of your container, involving the need for a good gasket or other means of sealing. Depending on the container, this may compromise the strength of the structure.

A possible alternative would be to use two PC radiators, which can run from fairly expensive to fairly cheap on Amazon or similar sites. Here's an example (just the first relatively cheap one I saw in a search, no affiliation): https://www.amazon.com/FITNATE-Aluminum-Exchanger-Radiator-10-62Inch/dp/B07C79CH67/. I would guess that fans would be pretty much essential, but one can get quiet fans. The bigger issue as far as noise and trouble is concerned would be flow of the liquid (water or anti-freeze mix or so on) - I don't know whether a heat siphon setup would suffice, or whether you would need a pump - and if a pump, how noisy that might be. Needless to say, this approach could get complicated, but it would have the advantage of only needing to put relatively small round holes in the container, which should be easy to seal and have little effect on structural integrity.

 

[cds4byu]

I agree with the worry about the structure, but the way I read his design, the box is not structural; it only holds up the lid. A heat sink bonded to a hole in the box with some kind of adhesive, or screwed in place and sealed with adhesive would seem to.meet the listed requirements.

If you used muffin fans on the heat sink you could mount it in the lid (because it wouldn't need to be vertical) and it would be at the hottest point in the box (best for taking heat out).

Carl

 

[awake]

I agree with the worry about the structure, but the way I read his design, the box is not structural; it only holds up the lid. A heat sink bonded to a hole in the box with some kind of adhesive, or screwed in place and sealed with adhesive would seem to.meet the listed requirements.

If you used muffin fans on the heat sink you could mount it in the lid (because it wouldn't need to be vertical) and it would be at the hottest point in the box (best for taking heat out).

Carl

This would definitely be the easier approach! As I was describing it above, I was thinking that my approach could get complicated ...

 

[Stone]

I have attached a picture of the box with the Synology NAS inside it