Water Cooling

[ollypenrice]

It seems a good idea. Atik Peltiers have the option to add watercooling but I've never used it. My friend and guest Ralph Ottow has a watercooled pimary mirror in his Newt. He likes his 20th wave optics to stay that way!!

Olly

[Gina]

Thanks Olly Now that's one high quality mirror!

[Photosbykev]

The water radiator design you've posted will provide very uneven cooling as it's designed like a stack of resistors (tubes) wired in parallel. Most of the flow will be through the lowest tube with little, or no flow, through the upper tubes.

You might find it better to have a single tube running through a spiral designed heatsink to maintain and maxmise the cooling effect along it's full length.

[Gina]

The water radiator design you've posted will provide very uneven cooling as it's designed like a stack of resistors (tubes) wired in parallel. Most of the flow will be through the lowest tube with little, or no flow, through the upper tubes.

Thanks for your thoughts on the matter That heat exchanger was my first thought - now abandoned.

You might find it better to have a single tube running through a spiral designed heatsink to maintain and maxmise the cooling effect along it's full length.

That was my second thought But after advice to go for a properly designed water block with much greater efficiency, I decided to buy a Zalman CPU water block. One of the things that swayed me was the difficulty I've found in getting a good flat surface on a copper sheet.

[Photosbykev]

flat and a mirror finish will give you the best heat transfer

[Zakalwe]

The water radiator design you've posted will provide very uneven cooling as it's designed like a stack of resistors (tubes) wired in parallel. Most of the flow will be through the lowest tube with little, or no flow, through the upper tubes.

You might find it better to have a single tube running through a spiral designed heatsink to maintain and maxmise the cooling effect along it's full length.

Or arrange it so that the outlet is diagonally opposite the inlet.

Thanks for your thoughts on the matter That heat exchanger was my first thought - now abandoned.

That was my second thought But after advice to go for a properly designed water block with much greater efficiency, I decided to buy a Zalman CPU water block. One of the things that swayed me was the difficulty I've found in getting a good flat surface on a copper sheet.

You'll still need a way to dump the heat-load from the water. The Zalman waterblock is designed to circulate water over the hot item. The water will then have to lose the heat...either by circulating through a radiator (which will need a pump....I would think that thermosyphoning wouldn't work), or by flowing over a surface that is mounted to a peltier. In fact, you might be able to use two of the Zalman blocks....one connected to the "hot" sensor, the other mounted to the cold side of the peltier. A small electric pump could be used to flow the water.

The other thing that might be worth considering is using heatpipes. A big CPU cooler might work, especially if you could mount the peltier between the heatsnk and sensor. It'd be bulky though!

[Zakalwe]

Or another alternative....buy a readymade CPU watercooler...something like this:

Corsair Memory Cooling Hydro Series H80 High-Performance CPU Cooler (CWCH80) - dabs.com

or this:

Corsair Memory Cooling Hydro Series H100 High-Performance CPU Cooler (CWCH100) - dabs.com

You wouldn't be able to assemble it for much less TBH

[Gina]

You'll still need a way to dump the heat-load from the water. The Zalman waterblock is designed to circulate water over the hot item. The water will then have to lose the heat...either by circulating through a radiator (which will need a pump....I would think that thermosyphoning wouldn't work), or by flowing over a surface that is mounted to a peltier. In fact, you might be able to use two of the Zalman blocks....one connected to the "hot" sensor, the other mounted to the cold side of the peltier. A small electric pump could be used to flow the water.

Yes, I still have to sort out some sort of radiator. I've already got a pump on order.

The other thing that might be worth considering is using heatpipes. A big CPU cooler might work, especially if you could mount the peltier between the heatsnk and sensor. It'd be bulky though!

Too bulky and too heavy.

[Gina]

Or another alternative....buy a readymade CPU watercooler...something like this:

Corsair Memory Cooling Hydro Series H80 High-Performance CPU Cooler (CWCH80) - dabs.com

or this:

Corsair Memory Cooling Hydro Series H100 High-Performance CPU Cooler (CWCH100) - dabs.com

You wouldn't be able to assemble it for much less TBH

Yes, I'm beginning to think that.

I've looked at this one :- Corsair CW-9060001-WW Hydro Series H40 Hydro CPU Cooler: Amazon.co.uk: Computers & Accessories

[Gina]

I don't think there's really any great difficulty in getting rid of heat from water. eg. I have some old CH radiators not doing much including quite a little one. I could take pipes out to the warm room, or to the outside. Just copper pipes alone would lose a fair bit of heat and we're only talking of something like 50W. Depends on how hot the water is, of course, and the idea is to have the returning water as cool as possible. Want the heat shed away from the scope though.

[The Sailor]

It was whilst reading a thread on here over the weekend that had me thinking of cooling a camera. I have already looked at stripping the camera to the bare bones and putting it in a light metal box with peltier and fans but that looked cumbersome. I was also at the same time organising a drip feed for her indoors tomatoes via a solar pump and this got me thinking, is there enough room in a camera for micro copper tube and to this end I am looking at boring two holes in the case so there is one continous run of tubing in and out and at each end a tube to the freezer contraption. All this of course is an idea yet to be looked at

Jim

[Psychobilly]

Your working in a differrent Temperature delta regime than you would with a CPU...

CPU dies run hotter than the sensors in the camera...

Sent from my GT-I9100 using Tapatalk 2

[iwatkins]

But the water cooling is for the hot side of a TEC which in turn cools the sensor. And the hot side of a TEC is easily up there with a CPU, so deltaT is similar.

Cheers

Ian

[Psychobilly]

But the water cooling is for the hot side of a TEC which in turn cools the sensor. And the hot side of a TEC is easily up there with a CPU, so deltaT is similar.

Cheers

Ian

I was answering sailors post the pipes to the sensor I should have quoted it like I did this time ...

Thats where the possible confusion came in... coupled with the way i read his post

Peter

Sent from my GT-I9100 using Tapatalk 2

[The Sailor]

Thanks Peter, I have been reading a number of threads on this subject and have to be honest I am a bit dumb . What I have been thinking about is a freezer unit running copper piping into the obsy and up the pier then rubber tubing to the camera, a bit Heath Robinson affair but I am looking at cooling the inside of the camera as low as possible.

Jim

[iwatkins]

Apologies Peter

Cheers

Ian

[Zakalwe]

Would you even need a cooler? A couple of gallons of cold water in a small barrel would probably do. Someone better at maths than me could easily work out how much heat the sensor puts out, and how much water you'd need to act as a heatsink.

[Psychobilly]

Apologies Peter

Cheers

Ian

No need Ian ... I shouldn't been lazy and quoted sailors post...

Sent from my GT-I9100 using Tapatalk 2

[Reggie]

You mentioned flat copper sheet, the term to look for is 'lapping', overclockers used to do it (Not sure if they need to these days as the flatness of a high-end cpu cooler is a selling point these days). Basically it's using sucessively finer grades of abrasive to get an ultra smooth finish on the thermally conducting surface that touches whatever it is you're trying to get heat away from.

[Gina]

Would you even need a cooler? A couple of gallons of cold water in a small barrel would probably do. Someone better at maths than me could easily work out how much heat the sensor puts out, and how much water you'd need to act as a heatsink.

I was thinking that too. I read somewhere that others have done that or similar, including using ice to provide a lower temperature.

When I was testing a cool box for whole camera cooling I used an 80mm CPU cooler and that was quite adequate to remove the heat generated when running the 12v 50W TEC at the full 12v and nearly 5A. The hot side was running at just a few degrees above ambient. Some form of simple heat exchanger could conduct the heat from the water to the cooler.

As has also been mentioned, a Peltier TEC could be used between heat exchanger and cooler to further reduce the water temperature but really I think this would be overkill. I want to keep things simple yet effective. The aim being to cool the image sensor to something like 5-10C with as little weight on the scope as possible with simplicity as the next consideration.

ATM the ambient night-time temperatures are low enough to provide 11-12C sensor temperature without TEC which is sufficient for my present wishes but I'm looking ahead to the summer (hoping we get one this year!). This is a longer term project - I've started recently due to not being able to check out my equipment on proper targets. Though last night was pretty good - more of which later in appropriate threads.

[Gina]

You mentioned flat copper sheet, the term to look for is 'lapping', overclockers used to do it (Not sure if they need to these days as the flatness of a high-end cpu cooler is a selling point these days). Basically it's using sucessively finer grades of abrasive to get an ultra smooth finish on the thermally conducting surface that touches whatever it is you're trying to get heat away from.

Yes, I was using cheapo copper sheet from eBay to make a heat conductor and support for the hot side of the TEC but found this unsuitable so I'm going for a proper professional water block directly on the TEC. Then that can be supported with a bracket.

[RAC]

I don't think there's really any great difficulty in getting rid of heat from water. eg. I have some old CH radiators not doing much including quite a little one. I could take pipes out to the warm room, or to the outside. Just copper pipes alone would lose a fair bit of heat and we're only talking of something like 50W. Depends on how hot the water is, of course, and the idea is to have the returning water as cool as possible. Want the heat shed away from the scope though.

My water is pumped through a small radiator that is sitting in a chillybin half filled with water. I put frozen milk bottles filled with water in the chilly bin to get the water nice and cold. Two frozen milk bottles keep me going for about 3-4 hours.

[Gina]

I've boobed! The Zalman water cooler came this morning and the CPU area won't cover the Peltier TEC. The bottom part that contacts the CPU is only 40mm diameter (round) and the TEC is 40mm square! I'm puzzled because I was sure the AMD CPU that I took the original 80mm sq cooler off was at least 40mm square. I've just checked the AM2 spec and chip size and it's 40mm square! The same size as my 12v Peltier TEC.

I thought the bottom of the Zalman water block had a cover on it that you took off to use it (to stop damage to the copper surface) but NO the instructions state clearly that the unit must NOT be undone and that precautions have been taken to stop dismantling. The thing is held together with 4 screws with tamper proof heads. Strangely, the bottom is NOT COPPER but appears to be chromium plated and not mirror flat by any means.

EDIT... The TEC MUST be cooled over the whole surface area or some of the cooling elements will overheat and destroy the unit. I thought much the same applied to CPUs - certainly the heatsink is bigger than the chip on all I've dealt with!

[Zakalwe]

A copper spreader plate, with a thin smear of heat transfer paste, sandwiched between the peltier and waterblock will sort this out.

[Gina]

A copper spreader plate, with a thin smear of heat transfer paste, sandwiched between the peltier and waterblock will sort this out.

The whole idea of buying a proper cooler was to avoid a copper plate in between and to provide better contact/conductivity.

Looks like I'll go for another make and decide whether to use the Zalman on the hot side of the water system to feed heat to one of my old CPU coolers, or to return it to Amazon for a refund. At least Amazon are alright with refunds

Sometimes I wonder why I bother - with anything!!! Still, at least I got some imaging time in last night for the first time in ages.