Trying to build a checkerboard where I can control the heat of all the black squares.

[SKN]

Or all the white squares. Basically I want fairly well-defined areas of high temp next to fairly well defined areas of lower temp. I think Peltier devices might be the way to go, but I'm not sure exactly how to figure this out. Any help would be appreciated! thanks!

 

[ericgibbs]

hi,
What temperature ranges are you working with, also how many squares and how big.??

E.

 

[SKN]

I think maybe 16x16 or 24x24. I'd like to make the size of the squares variable, if possible - anywhere from 2x2 to 6x6 or so. Temp ranges would be from maybe 15-35 celsius, although I'm flexible.

 

[SKN]

hi,
What temperature ranges are you working with, also how many squares and how big.??

E.

I think maybe 16x16 or 24x24. I'd like to make the size of the squares variable, if possible - anywhere from 2x2 to 6x6 or so. Temp ranges would be from maybe 15-35 celsius, although I'm flexible.

 

[ronv]

15 to 35 C would mean you have to cool them as well as heat them. Do you need that. It would be much easier to just heat them.

 

[BioniC187]

Pour some current through some power resistors. Make the squares out of aluminium, attach the resistor, and use PWM to control the temp to balance out the heat loss due to surface area of the squares

 

[SKN]

15 to 35 C would mean you have to cool them as well as heat them. Do you need that. It would be much easier to just heat them.

It would be good to have that level of control.

 

[SKN]

Pour some current through some power resistors. Make the squares out of aluminium, attach the resistor, and use PWM to control the temp to balance out the heat loss due to surface area of the squares

PWM? I am not well versed in this situation.

 

[ronv]

If you need to cool them below ambient as well as heat them the peltiers are probably the answer. I keep trying to talk you out of cooling them because it will add a lot of cost and complexity.

I think I would start out with an aluminum plate the size of the board as a heatsink. Then peltiers and the small metal squares. I would use some type of insulator for the white squares - maybe pcb material.
I think I would use two PC power supplies for the peltiers so you would have a + and - 12 volt supply. If we are on the right track we can talk about temperature control.

 

[SKN]

If you need to cool them below ambient as well as heat them the peltiers are probably the answer. I keep trying to talk you out of cooling them because it will add a lot of cost and complexity.

I think I would start out with an aluminum plate the size of the board as a heatsink. Then peltiers and the small metal squares. I would use some type of insulator for the white squares - maybe pcb material.
I think I would use two PC power supplies for the peltiers so you would have a + and - 12 volt supply. If we are on the right track we can talk about temperature control.

I've got a pretty good amount of money to work with, so I'm not worrying about cost at the moment. So just to be clear (because I am really a novice at this type of thing), the board would be aluminum. Where would the peltiers go? On the bottom? Do you think this would allow for variable sized squares? So then, the white squares are insulated. Do you think I need peltiers for teh whole board? Probably because I want to control the temperature everywhere.

Thanks for your help, I seriously do not know what I'm talking about here.

 

[ronv]

Some more info would be helpful. Like what is this for??

I have a vision now of a 12 foot by 12 foot checkerboard with 6 inch squares.

Peltiers are maybe 40 mm so maybe some multiples could be worked out but it is easier if the end result is a known.

 

[BioniC187]

Oh it's gonna be large! i was thinking small scale, like a 30cm by 30 cm
Even so, when you say you want different squares of hot and cold, you mean just that right? so that someone can touch and say, "that is hot" and "this is cold". coz if so, then i don't feel the need for a peltier route. too complex for something not so complex

 

[BioniC187]

Rather loop the "cold" squares in a water cooling loop. Far cheaper. Forgive me, but i'm all for making things cost effective and going for a simple solution as far as possible. Perhaps tell us what it will be used for, and where etc

 

[JimB]

Consider:
a cool plate will be surrounded by four hot plates.
Keeping the cool plate cool will be quite difficult.

Similarly:
a hotplate will be surrounded by four cool plates.
Keeping the hot plate hot will be quite difficult.

JimB

 

[BioniC187]

No, there will be insulation between the plates, i thought that was a given. You can get thin pieces of plastic, about 1.5mm thick to place between like a grid and slot the plates between that. the only thing giving heat transfer to nearby plates will be air, and that won't happen in a hurry

 

[blueroomelectronics]

Unless all plates are actively cooled / heated they'll reach equilibrium probably sooner than later.