Results 1 to 30 of 30
  1. #1
    Joep Hogenhout's Avatar
    Joep Hogenhout Guest

    Question Cooling down the water in a 1000 liter container



    Dear refrigeengineers,

    A question.

    I'm in lasershow business and when I have outdoor party's I use 1 or 2 1000 liter water containers to cool the lasersystem.

    When I use 1 1000 liter container that water is in about 1 till 2 hour 30\40 degrees celsius when I drive the laser with DC 30A secondary current. The laser needs water with a maximum temperature of 30 degrees celsius, and 8.5 liters/min or 2.2 gal/min

    Is there a way to cool the water down to about 10 degrees stable? Please keep in mind that the laser must be able to run the whole night.

    If it is possible to cool down such containers, maybe it's also possible to look for a smaller solution as the 1 by 1 meter 1000 liter containers, because then I not need such big vehicle to move the containers. The cooling device must cool alot quicker when I use a smaller container instead of a 1000 liter one.

    Thanks
    Last edited by Joep Hogenhout; 17-03-2004 at 05:01 PM.



  2. #2
    Join Date
    Sep 2003
    Location
    ISRAEL
    Age
    72
    Posts
    4,266
    Rep Power
    46
    hi joep,

    the laser machines I know are for cutting,
    each one comes with a small chiller to keep the water cool without a reservoir.

    I think it will be easier for you to carry a small chiller instead of a 1000 litre tank the water ca go down to 23C, under that temperature you might get condensation and you dont want it.

    so if you tell me in what temp. the water are coming out.
    I can tell you the size that you need.

    this way you will not need any container.

    chemi

  3. #3
    Join Date
    Oct 2003
    Location
    Belgium
    Age
    62
    Posts
    5,645
    Rep Power
    34

    Re: Cooling down the water in a 1000 liter container

    Originally posted by Joep Hogenhout
    When I use 1 1000 liter container that water is in about 1 till 2 hour 30\40 degrees celsius when I drive the laser with DC 30A secondary current. The laser needs water with a maximum temperature of 30 degrees celsius, and 8.5 liters/min or 2.2 gal/min

    Is there a way to cool the water down to about 10 degrees stable? Please keep in mind that the laser must be able to run the whole night.
    Worst situation, 1000 liter was heated in hour from 10 to 40°C.
    So you need a cooler of 1000 x 30 x 1,16 = 34 kW.
    MOost positive situation : 1000 l in 2 hour from 15 to 30°C =
    1000 *0.5 x 15 x 1.16 = +/- 8 kW.

    So your figures should be more precise to calculate your machine.

    I should go for this configuration for a Rhoss (relative cheap and good quality, everything build into it, pump, buffer, made to install outside..) of +/- 15 kW.

    You can also consider to install 2 independent machines so that you will have a safer setup. If one fails, then you always have the other one as a backup.

    You will need +/- 20 to 25 l/kW so 500 l should be sufficient.
    Last edited by Peter_1; 17-03-2004 at 10:02 PM.

  4. #4
    Join Date
    Sep 2003
    Location
    ISRAEL
    Age
    72
    Posts
    4,266
    Rep Power
    46
    peter,

    he just wants to cool the laser head and you give him too much,
    mixing valves and thermostates.

    why not a chiller as you advised about 20KW and connect it straight to the laser?

    MTK also make that kind of small chillers.

    chemi

  5. #5
    Join Date
    Oct 2003
    Location
    Belgium
    Age
    62
    Posts
    5,645
    Rep Power
    34
    Originally posted by chemi-cool
    he just wants to cool the laser head and you give him too much, mixing valves and thermostates.
    Why not a chiller as you advised about 20KW and connect it straight to the laser?

    Agree Chemi, will edit my previous post.

  6. #6
    Join Date
    Sep 2003
    Location
    ISRAEL
    Age
    72
    Posts
    4,266
    Rep Power
    46
    good idea marc,


    since lasers work at nights and the ambients fall down any way,

    to be safe, I would add a chiller as backup.


    chemi

  7. #7
    Join Date
    Oct 2003
    Location
    Belgium
    Age
    62
    Posts
    5,645
    Rep Power
    34
    Hmmm,...Holland same weather as here.
    If you need water of 10°C, then at least ambient of 5°C. Get never that cold, except for some months during winter.

  8. #8
    Join Date
    May 2002
    Location
    The Netherlands
    Age
    48
    Posts
    274
    Rep Power
    22
    Mr. Hogenhout, I see you live in The Netherlands. I cannot help you, but I know a company/person who is very capable of helping you with this problem. You know, one of those belonging to the top 5% of their trade. If you need contact information, send me a private message or an E-mail.

  9. #9
    Joep Hogenhout's Avatar
    Joep Hogenhout Guest
    I would like the cheapest solution, because I've invested a lot of money in the laserdevices.

    I like to make it myself, that's no problem.

    Maybe I can make a bigger heat exchanger then on: http://www.icecoldcomputing.com/text...page.php?id=23

    With a phase change setup from a big refrigerator.

    Can I change the cooling part in the refrigerator with the self made heat exchanger without problems?

  10. #10
    Join Date
    Oct 2003
    Location
    Belgium
    Age
    62
    Posts
    5,645
    Rep Power
    34
    Originally posted by Joep Hogenhout
    I would like the cheapest solution, because I've invested a lot of money in the laserdevices.

    Cheapest or best? Think the chiller will cost a fraction of your lasers.
    You have to make the choice: don't do anything or install a DIY cooler like you described and destroy your lasers or do it the way it has to be done, with other words,... like a pro.

    I like to make it myself, that's no problem.

    Maybe I can make a bigger heat exchanger then on: http://www.icecoldcomputing.com/text...page.php?id=23

    With a phase change setup from a big refrigerator.

    Can I change the cooling part in the refrigerator with the self made heat exchanger without problems?
    Which self made exchanger?
    No, you can't.
    Seems that with this suggestion you don't have a clue how those systems work.

  11. #11
    Joep Hogenhout's Avatar
    Joep Hogenhout Guest
    Yes indeed, I don't know how it exacly works.

    I can run a whole night, but then I must turn the laser on and off every time I've performed a show.

    This is only an option but I not want to spend a lot of money to it.

    I want to make a system that I can use @ the water out of my power supply. From there comes out the warm water.

    That has to be cooled.

    I love to make things by myself, but I haven't got any experience with this sort of cooling stuff

  12. #12
    Join Date
    May 2002
    Location
    The Netherlands
    Age
    48
    Posts
    274
    Rep Power
    22
    Originally posted by Joep Hogenhout
    I would like the cheapest solution, because I've invested a lot of money in the laserdevices.
    Isn't that a good reason to use a decent cooling device?

    I like to make it myself, that's no problem.
    That is harder than you think...

    Maybe I can make a bigger heat exchanger then on: http://www.icecoldcomputing.com/text...page.php?id=23

    With a phase change setup from a big refrigerator.
    A 'big refrigerator' does about 300W at best (to keep it simple). Compare this to the amount of power you feed into your laser power supply. The heat must go somewhere, and 99% ends up into the cooling water.

    Can I change the cooling part in the refrigerator with the self made heat exchanger without problems?
    Sure, if you scale up everything 1000x, it would maybe work. Maybe not.

    Start by telling us how much heat you need to get rid of.

    If you intend to go the DIY route, I would suggest to add one or more car radiators with large fans on them. This would make a difference, but I don't know how much. On the other hand, it's cheap to try.
    Maybe adding a car

  13. #13
    Join Date
    Oct 2001
    Location
    Nottingham UK
    Posts
    5,733
    Rep Power
    51
    What sort of car Da Bit?????

  14. #14
    Join Date
    Oct 2001
    Location
    Nottingham UK
    Posts
    5,733
    Rep Power
    51
    Hi Joep

    As the guys have said, yes it is possible to achieve cooling to your equipment without having to lug 2 x 1000 litre tubs of water around but everything has a price. The tubs of water act as a passive heat sink so as your lasers heat up the excess heat energy is transfered to the water (or heat sink) and is dissapated, which allows your lasers to keep on working.

    From what you say, it looks like the 1000litre or 1000kg of water rises in temperature about 10deg C per hour. This equates to about 12kw of heat load. You can of course buy refrigeration equipment which will handle this load but are you prepared to invest? Only you know the answer. We of course can offer (collectively) the best solution to your dilema but you need to advise us which way to go. Balls in your court mate - as they say!

  15. #15
    shogun7's Avatar
    shogun7 Guest
    This may be of some value to you!
    http://teryx.bobdbob.com/~protius/lasercooling/
    Roger

  16. #16
    Join Date
    May 2002
    Location
    The Netherlands
    Age
    48
    Posts
    274
    Rep Power
    22
    Originally posted by frank
    What sort of car Da Bit?????
    Uh, oops

    But to elaborate on the car radiator idea: Just use what you can get for free/cheap. It is probably not good enough to keep the water temperature below the 30 degrees on every circumstance, but it could work.

    And why does the topic starter want 10C water? It seems to me that 20C or 25C water would be sufficient too.

    This may be of some value to you!
    http://teryx.bobdbob.com/~protius/lasercooling/
    Roger
    That's about cooling a small (100mW or so) argon-ion laser head. I expect the topic starter to use more colorful kryton-ion laser tubes.

  17. #17
    Join Date
    Oct 2003
    Location
    Belgium
    Age
    62
    Posts
    5,645
    Rep Power
    34
    14 kW chiller will cost +/- 2.000 Euro.

    Or make a small adiabatic cooler wit he the car radiators from Dabit and spray some of the water you use for your circuit in the radiator with fuel nozzles (For example Danfoss) they use in ordinary fuel burners.

    I did this to cool down some years ago a huge space where a friend of mine had +/- 10.000 rabbits were inside and due to the heat of that summer, one after the other got a heard attack (the rabbits ).
    Last edited by Peter_1; 19-03-2004 at 09:35 AM.

  18. #18
    Joep Hogenhout's Avatar
    Joep Hogenhout Guest
    It's a 6 watt argon laser I use.

    The temperature of the water that goes in the tube may not exceed the 30oC (86oF).

    But I better can keep the water about the 10 till 15 degrees just for safety. 20 is also possible. but that is a little bit to high tolerance.

  19. #19
    Join Date
    May 2002
    Location
    The Netherlands
    Age
    48
    Posts
    274
    Rep Power
    22
    If I recall correctly, a 6W Ar-ion laser tube needs about 280VDC @ 35 amps max.

    Thus, power input is about 10kW max (of which 6W is light output).

    At 30 amps and ~260VDC it's about 7.8kW.

    power supply produces another ~2kW, if it is also watercooled.

    Thus, 12kW cooling load is a good guess.

    At 8.5 liters/min coolant flow, which is 0.142 l/sec, the exit temperature of the water would be 12000 / (0.142*4200) = ~20C warmer than the inlet.

    If we have a 20C ambient (not unusual in The Netherlands in the summer at night), and use 25C water at the inlet, we have 45C water at the inlet of the car radiators. At this inlet temperature and with decent airflow they can reject quite a lot of heat.

    A 100pk car engine under full load also dumps ~25kW of heat into the coolant which is rejected by the car radiator, though at a much higher temperature.

    A very rough guesstimate: with 4-6 car radiators (from 100pk cars ) and adequate airflow you should be able to keep your liquid cool enough.

    How would I build such a system? I'd make a box of flightcase wood, mount the car radiators on the sides of the box, and use a few powerful fans sucking air through the radiators mounted in the remaining sides of the box. The water pump can be inside the box as well.

    I don't see why you would want water cooler than 20C. The purpose of the water cooling is to prevent the laser from overheating, and I don't see how cooler water would prolong the tube life. Even worse: too cold water causes condensation/sweating which can't be good for the tube.
    Your optics are the weakest points in such a laser.
    Last edited by DaBit; 19-03-2004 at 02:18 PM.

  20. #20
    Join Date
    Sep 2003
    Location
    ISRAEL
    Age
    72
    Posts
    4,266
    Rep Power
    46
    hi dabit,

    earier on this thread I have warned joep about condensation. its fatal for lasers.

    I maintain a foctory that uses big lasers for cutting metals.

    you do not need a big chiller, and if you use a dry cooler, it can all be on a trailer and the chiller can only used as a backup.

    chemi

  21. #21
    Joep Hogenhout's Avatar
    Joep Hogenhout Guest
    But DaBit,

    Can't I use the heat exchanger that you've build on your website in combination with a cooling installation of a big refrigerator?

    Then I can fill the heat exchanger spiral with coolant that also is in the refrigerator system. The water out of the power supply I can point through the evaporator housing.


    I mostly run the laser on a standard water outlet in discotheques, there is the temperature also about 10 degrees. I've never had any troubles with condensation.

    And when, the tube and optics can handle it, because the optics are protected with an airtight cover over the brewsters.

    Only the powersupply could be damaged by it, because the transistors from the passbank become wet.
    Last edited by Joep Hogenhout; 19-03-2004 at 04:54 PM.

  22. #22
    Join Date
    Oct 2001
    Location
    Nottingham UK
    Posts
    5,733
    Rep Power
    51
    Thus, 12kW cooling load is a good guess.
    A good guess! the calculation brought it out at 11.63888kw so I rounded it up to 12kw

  23. #23
    Joep Hogenhout's Avatar
    Joep Hogenhout Guest
    Nice picture frank

  24. #24
    Join Date
    May 2002
    Location
    The Netherlands
    Age
    48
    Posts
    274
    Rep Power
    22
    Originally posted by Joep Hogenhout
    [B]But DaBit,

    Can't I use the heat exchanger that you've build on your website in combination with a cooling installation of a big refrigerator?
    Sure, if you exchange the 'big refrigerator' with a unit which is many times more powerful (let's say about 3 A/C outdoor units as seen on shops and office buildings), and my heat exchanger on steroids.

    Then I can fill the heat exchanger spiral with coolant that also is in the refrigerator system. The water out of the power supply I can point through the evaporator housing.
    The basic idea is OK
    If you want a more thorough understanding of how a refrigeration system works, I suggest www.refrigerationbasics.com

    Only the powersupply could be damaged by it, because the transistors from the passbank become wet.
    At 10C the risk is not so high due to the temperature difference between the silicon and heatsink. But it's critical, especially in damp discotheques (I've been doing drive-in for years).

    Anyway, you really seem inclined to go the DIY-route. If I can do so, so can you. It's just a larger scale.

    Make sure that you understand how refrigeration works. That will help.

    BTW: I sent you a PM about the guy I was talking about.

  25. #25
    Join Date
    Mar 2002
    Location
    San Francisco Bay Area
    Posts
    180
    Rep Power
    23
    Designed a laser cooling system a few years ago. Laser was for cutting. Laser manual provided water temp & flow rate specifications. Installed a cooling tower and a three-way valve to prevent temperature from dropping too low at low ambients.

    Laser was aimed using small mirrors, computer controlled, each with a heat sink on the back with a channel bored for coolant circulation. Water temp had to stay above dew point to prevent condensation on the mirrors.

    Saved the customer a bit of money, using an open-loop cooling tower, but due to the water treatment hassles, he bought a chiller with his next laser.

    Rog

  26. #26
    Join Date
    Jan 2008
    Location
    India
    Age
    70
    Posts
    171
    Rep Power
    17

    Re: Cooling down the water in a 1000 liter container

    you can have tank &coil with condensing unit attached to cool the water which will work out simple r and simple

  27. #27
    Join Date
    Apr 2009
    Location
    earth
    Posts
    25
    Rep Power
    0

    Re: Cooling down the water in a 1000 liter container

    Quote Originally Posted by Sridhar1312 View Post
    you can have tank &coil with condensing unit attached to cool the water which will work out simple r and simple

    i think this will work we have tried like this set up in a shampoo manufacturing. although you really need to invest on the equipment

  28. #28
    Join Date
    Oct 2003
    Location
    Belgium
    Age
    62
    Posts
    5,645
    Rep Power
    34

    Re: Cooling down the water in a 1000 liter container

    This thread is standing up out of his grave
    It's better to keep your mouth shut and give the impression that you're stupid than to open it and remove all doubt.

  29. #29
    Join Date
    May 2007
    Location
    Auckland
    Age
    74
    Posts
    3,362
    Rep Power
    37

    Re: Cooling down the water in a 1000 liter container

    Well said Pete 1, like a pheonix rising out of the ashes 5 years later. The original poster has probably retired by now. Short of reading all posts, did any suggest throwing some ice in the tank, would be quick and cheap ?.

  30. #30
    Join Date
    Apr 2009
    Location
    earth
    Posts
    25
    Rep Power
    0

    Re: Cooling down the water in a 1000 liter container

    hahaha sorry i'm new hir i didn't notice it was dated 2004 i just reply on the last quote which is 2009. really sorry

Similar Threads

  1. cooling water TDS
    By afeef in forum Technical Speculations
    Replies: 1
    Last Post: 19-04-2009, 07:38 AM
  2. pure water from air
    By Lc_shi in forum New Technologies
    Replies: 32
    Last Post: 26-02-2009, 01:25 PM
  3. Cooling tower evaporation, blowdown, makeup and cycles
    By miltbeychok in forum Industrial
    Replies: 5
    Last Post: 14-10-2005, 06:34 PM
  4. Cooling tower evaporation, blowdown, makeup and cycles
    By miltbeychok in forum Fundamentals
    Replies: 0
    Last Post: 13-10-2005, 05:14 AM
  5. Building a wine cabinet
    By Rory in forum Technical Discussions
    Replies: 38
    Last Post: 13-07-2004, 08:28 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •