Cooling requirements for closed environment

Discussion in 'UDOO X86' started by Alicia Billings, Jan 4, 2018.

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  1. Alicia Billings

    Alicia Billings New Member

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    Hello everyone,
    I am considering purchases 4-5 of these to use as stations to process biological measures on a ship. My design requires that these are housed inside Pelican-type cases to allow for water resistance against splashing. While there will be holes drilled in the sides for wet pluggable bulkhead connectors, they will be set in with silicone. Anyway, there will be minimal air movement for cooling.

    My question: Do you think the CPU fan will be sufficient for cooling in this environment?

    Thank you!
     
  2. LDighera

    LDighera UDOOer

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    In my experience, the un-housed/bare-board Udoo X86 Advanced Plus seldom activated the heat-sink fan, only occasionally while viewing YouTube videos.

    Placing the X86 in a very well ventilated aluminum case results in more frequent fan operation. So, it is evident to me that some means of conducting the heat outside the Pelican case will be necessary for operation beyond a few minutes.

    You might consider a 3M Novec immersion liquid cooling solution: Video. Such passive cooling would be preferable to a liquid cooling system employing a pump and heat exchangers.
     
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  3. Alicia Billings

    Alicia Billings New Member

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    Thanks LDighera, that's an interesting solution I hadn't thought of before. I'll look into it.
     
  4. waltervl

    waltervl UDOOer

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    If you put the UDOO in a waterproof metal housing instead of a plastic (thermal insulating) housing the heat transfer through the metal walls could be good enough to keep the Udoo on a working temperature. You can also add extra cooling finns on the outside. You can also thermally connect the processor with the metal housing (metal spring) so the housing functions as a big heat sink.
    This could be an example: https://www.spartonre.com/littlepcs/fanless-mini-pcs/wpc-725f-rugged-fanless-waterproof-pc/
     
    Last edited: Jan 4, 2018
  5. waltervl

    waltervl UDOOer

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    See also this video to give an impression of such a case:
     
  6. Alicia Billings

    Alicia Billings New Member

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    Thank you waltervl! I'm not married to the idea of a plastic case, so this is a great option as well.
     
  7. Alicia Billings

    Alicia Billings New Member

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    So I've been going over this in my head for the past hour, and now I'm wondering if it would make a difference if the plastic case was much larger than the board (say ~460mm x 330mm x 175mm). I can bring in all of the necessary converters (like a serial to ip) and make the whole thing watertight instead of having everything separate.

    Even though the plastic case is still sealed, do you think there would be enough air movement in this larger case to be able to run for hours at a time using just the heatsink and fan? Or do you think there would still be a problem of the plastic case trapping the heat?

    Thanks,
     
  8. waltervl

    waltervl UDOOer

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    Keeping all the electronic devices in one box is definitely a better option. But all the electric devices consume power and generate heat also. Is the box lying in open air in the sun? What will be the average open air temperature? How long will the box be closed?

    When closed for a long time the box has to transfer the generated heat through the wall to the free air.
     
  9. Alicia Billings

    Alicia Billings New Member

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    The box will be under a stainless steel table, but all sides are open to the ambient air. It will be used on a ship in the northeastern Pacific Ocean, so the temp will be around 10-15C max. In a perfect world, I won't need to open the box at all. However we do have access to a dry lab space where it can be opened away from any danger of water splashing inside after all operations are complete. While the length of time varies for each use where it would need to be running, the average is about 3 hours at a time.

    I'm also thinking of writing something that will force the udoo to shutdown after 20-30min in an idle state so it won't be running all day long, in case one of the operators forgets to shutdown after operations are complete.

    Thanks,
     
  10. waltervl

    waltervl UDOOer

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    I still would use a metal box. It is easier to control and modify heat transfer if it is not sufficient after testing.

    Idling the Udoo could be just a setting in the OS like a normal pc shuts down after X minutes of idle state.

    Are you going to use the Arduino 101 (curie) side or the Braswell side to monitor the sensors?
     
  11. Alicia Billings

    Alicia Billings New Member

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    After looking into this some more, there are two reasons why I'm reluctant to go with a purely metal box: 1. I'd like to be able to use bluetooth/wifi for future applications and 2. it will be splashed with saltwater, although I guess something that is coated would help that aspect.

    What if I cut out a space on the box to add a metal plate (and then somehow figure out how to seal it so water doesn't get in)? Maybe one with some fins to increase airflow?

    As far as sensors go, I'm not using any for this particular project. I'm attaching serial devices via a serial to IP converter, and then plugging that into the udoo. We need to read in nmea strings from scales, length boards, barcode scanners, etc. and are limited by the products we already have on hand (ie, budget is fairly low).

    Thanks,
     
  12. waltervl

    waltervl UDOOer

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    Why buy a Udoo then? Buy a raspberry pi and you are good. There are waterproof boxes for these boards commercially available too. (Sorry Udoo team :) )
     
  13. Alicia Billings

    Alicia Billings New Member

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    Ha! Good point...

    Main reason I'm looking at Udoo vs Raspberry pi is that I'd like to have a full version on Windows running on it. Our acquisition software is written in python so theoretically it should be fine, but it hasn't been tested on a linux distro. I keep meaning to run it on a virtual machine, but other things always get in the way.
     
  14. waltervl

    waltervl UDOOer

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  15. Alicia Billings

    Alicia Billings New Member

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    You are a wealth of information, watervl. Thanks for all your help!
     
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