[PSUBS-MAILIST] pulled thread line - submarine AC and heat

[Alan via Personal_Submersibles]

Hi Brian,
I have just named a file "air conditioning" as I couldn't find any of my 
past research.
I don't know how many peltiers. If you based your air conditioning system
on a car which uses 4 hp or 2,980 Watts & factored in that peltiers are 1/4
as efficient as conventional air conditioning then you would need 11,920 W
to get the equivalent cooling! And then it's an unknown as the peltiers are
more efficient when there is a larger temperature differential between sides.
So when you really need AC in Florida, because the water is warm, the peltier
will be less efficient ( as I presume the AC system will be ).
Directing the ducted cold air on to you rather than trying to cool the whole 
sub is the best way to go.
I have heard that some commercially available subs use a lot less power in their 
AC systems than cars. Cars don't sit in water, so subs have that advantage.
As I have said, peltiers are an efficient heater, so there is no waste putting them
in even if you have a not so good air conditioner.
With the boat air conditioners you have to get rid of the heat they produce
to the water which could be a problem with pressures that subs go down to.
If you force an air stream over the peltiers moisture will condense on them so
maybe mount them on a slope with a drain at the bottom.
I was thinking of mounting them with a heat transfer glue either direct to the 
hull or on an Aluminium heat sink that is bolted in contact with the hull.
If I went with the Aluminium heat sink I would have to ensure the contour 
of the heat sink matched the hull perfectly & add some heat transfer paste.
I like the heated vest idea. 
Phil Nuyten said Nuytco used an external air conditioner & kept the sub cool
that way before diving. They also had vests with pockets that they stored
re freezeable chilly pads in.
Alan




> On 3/04/2019, at 12:15 AM, Brian Hughes via Personal_Submersibles <personal_submersibles at psubs.org> wrote:
> 
> Alan,
> 
> How many peltier chips do you think you'll use? Or need? I was kinda planning the same idea, but was trying Kydex. I made a cover with a thin sheet of clear plastic, but I wondered about durability. Hadn't thought fiberglass. Doh.  The real reason is I picked up for free a vacuum thermomolding machine and needed an excuse to play. 
> 
> As per attachment I was thinking magnets, the chrome covered ones you can get a home depot. Attach where needed.  Spread heat transfer paste on the surface, etc. How will you attach yours? Building in piping for condensation runoff? 
> 
> For heat I'm going with a cigarette lighter socket into which I can plug my heated vest I use on cold days on the Harley. Keep the core warm, etc. 
> 
> Get Outlook for Android
> 
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