Design Engineer Needed! Peltier Cooler Design Help!
I’m new to Peltier modules, heatsinks, CPU fans, and thermoelectrics. I need help figuring out how to efficiently match those components together. I’ve been more of a mechanical designer rather than an electro-tech designer.
I am designing an Aeroponic system and I need a way to cool my nutrient reservoir. My goal is to bring the temperature of a 3-5 gallon water container down from 85 degrees Fahrenheit to 50 degrees Fahrenheit. Here’s the link to the design I'm trying to base my design off: http://www.novatecproducts.com/iceprobe.htm
The diameter of the probe is 1-1/4”. I thought about doing a simple cooling plate but couldn’t seal it against a cooler or plastic container as well as I could a bulkhead style probe fitting. They don’t sell probes like that and no one else makes anything close to that kind of thermal transfer probe so I had to make one. I couldn’t find an aluminum bolt or all-thread in 1-1/4” diameter so I got a piece of 1-1/4” aluminum round bar and threaded one end to fit a flat aluminum flange and got an aluminum flat lock nut to seal it against the wall of the container. I plan to use the aluminum flange of the probe as the thermal face that will contact the cold side of the Peltier module and transfer the cold temp down the probe and into the water. The flange is a 4-1/2” diameter circle so I want to find a Peltier chip that will fit under it nicely and be as cooling efficient as it can be. I need to cool a 3-5 gallon container from 85 degrees Fahrenheit to 50 degrees Fahrenheit but it’s going to have a controller so if the chip can cool more than that, it would be preferred because I might change the size of my reservoir and I want it to be strong enough to cool a larger size water tank or insulated box. If the module is able to cool it more than what I’m needing, the controller won’t have to run it as long, which would mean less power draw. I could use those huge Heatsinks with two and three fans with pipes that looks like a hot rod engine, but since the Peltier device will be sitting on the side of the water tank, the heatsink can’t be very heavy or stick out very far. So I need to match the Peltier module with a heatsink and CPU fan that will effectively cool the Peltier module that I’m looking for. I was thinking about using a heatsink like this: https://www.google.com/shopping/product/886015867783779298?q=efficient+cpu+heatsink&client=safari&hl=en-us&biw=414&bih=719&tbs=vw:l,ss:44&prmd=sivn&sxsrf=ALeKk02wST30IOo2hK7zmStKgUnU86Q0dQ:1593026927993&prds=epd:11304467210571878547,cdl:1,prmr:1,cs:1
I thought of this heatsink because it is thin and won’t be hard to mount on the side of a container and it has the cooling pipes like the bigger brothers to it that look like the hot rod engines. The Peltier module also has to fit on the heatsink plate so I have to consider the size of the heatsink that I will need to fit a Peltier module of the size I need. Since the device will be close to water, I was hoping to find a waterproof module or find something that will seal it up so water can’t get to the electronics. I am buying thermoelectric epoxy glue, could that be used to seal all under and around the Peltier module to make it waterproof? I don’t know much about CPU fans but I was hoping a heatsink like from the link with the fan would be okay to withstand the heat of the Peltier module. I know some CPU fans can’t take that much heat. I think the fan and the Peltier module have to work on the same power, so I have to make sure that when I wire the red wires from the Peltier and fan together and the black wires from the fan and Peltier together that the power supply is going to make them both run as they are intended to be and not overpower one and underpower the other. Since I’m using a controller, the fan and Peltier module have to match the power of the controller so I have to find a controller that will be easy to set up and control my Peltier cooling device. Thanks for any help.
2 Replies
So you want to take a TEC mount it on this storage tank, Cold side facing the tank, other side hotside you will have a fan heatsink combo removing the wast heat. Thermal glue would be fine, the units are sealed pretty well, caking it all over would not be needed.
If you want to control it via PWM or simple on off you can find them pretty easy
Sounds interesting. Let me know how I can help.