Alireza

There are all sorts of Peltier coolers on the market. Why re-invent the wheel?

Hi, remember Peltier has very low COP or efficiency; not useful for relatively large volume

There are all sorts of Peltier coolers on the market. Why re-invent the wheel?

Hi, remember Peltier has very low COP or efficiency; not useful for relatively large volume

When you "create cold", you're really just "pumping heat". That is, moving heat from one place to another. Without moving parts, a peltier cooler is about your best bet, but while they are capable of creating quite a wide temperature differential--and some designs can even get to cryogenic temperatures--they can't generally move very much heat. If your intention is to create an air conditioner, it will work, but it won't be able to move enough heat fast enough to chill a room, for example.

 

So, what are you up to? If you can give a few more details, I am sure we can come up with some hints. For example, you can do it without electricity if you only want cold for an hour or two. Dry ice can be used to cool a liquid which can then be pumped through a radiator. If you want really cold air, that is a good option.

 

If on the other hand, you're just trying to make a simple and inexpensive air conditioner for a room, you can do what "they" did before air conditioners were invented: evaporative cooling. Take a regular fan, a pan of water and some strips of thick cloth. Soak the cloth and put the ends in the pan of water. When the fans blow across the cloth, it will cool the air as the water evaporates. It will also help increase humidity, if you live in a dry climate like I do.

 

If you're just interested in cooling a small space, perhaps the size of a soda cooler, peltier is a great choice. Depending on ambient temperature, you can expect to cool a cubic foot or two down to about 45 F or so. I recommend just going to a department store and buying a premade cooler. I believe "Coleman" makes one.

 

So, what is your application? We know you want to cool air, but to what temperature, on what scale, and for what purpose?

 

-Caver

Hi Cover,

Your explanation was really helpful and thorough which i really liked it. I am working on special type of stirling cooler in small size, any idea where to prapare? I already have a medium size one, wonder why small siza of it is not available. I will let you know what is in my mind finally.

You can use a Stirling cycle Cooler. Some small coolers are about the length of a 30cm ruler (so, about 30cm). They don't have a lot of moving parts - just a linear motor driving a piston.

 

It's very efficient and larger ones can cool to cryogenic temperatures. Of course, it takes up a bit of space.

Please let me know where did you find/buy a small stirling cooler? I have a big size but could not find a small size, thank you.

Hi, I am Alireza , PhD student in mechanical engineering at UIUC, and interested in Renewable energy, solar cooling, biomedical device design and more..