Battery Powered Nichrome wire Heater help

[hbard21]

Hello, I am new to this and need some help designing a project of mine.

I am trying to build a small battery powered heater using nichrome wire. I am going to be heating a liquid within a coiled copper tube and plan on heating it by wrapping the tube in nichrome wire.

Since this is a small project I need it to battery powered.

I am not sure about the exact temperature I wish to reach, but it is in between 120-200 degrees fahrenheit.

Also, I want this to heat up as fast as possible, so as I am aware the thinner gauge the wire, the faster it heats up, but I have also herd that thinner wire tends to break. However, since I am only heating it up to around 200 degrees, will this be a problem?

Basically what I need help with is what gauge wire I should be using and how much battery power will it take to heat it. Since it is small scale I was planning on using the smallest batteries possible, but this is just a prototype, so if someone could just tell me what voltage of battery I would need that helps just as much.

The tube in which the nichrome will be wrapped around will be around 3/8 of an inch thick.

Also, I have herd that the shorter the distance of wire, the faster it will heat. In my case, I want this heater to heat as fast as possible, hopefully in between 0 to 10 seconds. Therefor I have been considering dividing the nichrome wire that is to be wrapped around the tube to be sectioned off and powered independently from the next section, so it will heat up faster.

Please, I would appreciate any information and input anyone has to offer, thank you!

 

[mdjensen22]

does something like this help?
http://www.jacobs-online.biz/nichrome/NichromeCalc.html

 

[berkeman]

Hello, I am new to this and need some help designing a project of mine.

I am trying to build a small battery powered heater using nichrome wire. I am going to be heating a liquid within a coiled copper tube and plan on heating it by wrapping the tube in nichrome wire.

Since this is a small project I need it to battery powered.

I am not sure about the exact temperature I wish to reach, but it is in between 120-200 degrees fahrenheit.

Also, I want this to heat up as fast as possible, so as I am aware the thinner gauge the wire, the faster it heats up, but I have also herd that thinner wire tends to break. However, since I am only heating it up to around 200 degrees, will this be a problem?

Basically what I need help with is what gauge wire I should be using and how much battery power will it take to heat it. Since it is small scale I was planning on using the smallest batteries possible, but this is just a prototype, so if someone could just tell me what voltage of battery I would need that helps just as much.

The tube in which the nichrome will be wrapped around will be around 3/8 of an inch thick.

Also, I have herd that the shorter the distance of wire, the faster it will heat. In my case, I want this heater to heat as fast as possible, hopefully in between 0 to 10 seconds. Therefor I have been considering dividing the nichrome wire that is to be wrapped around the tube to be sectioned off and powered independently from the next section, so it will heat up faster.

Please, I would appreciate any information and input anyone has to offer, thank you!

Can you please tell us more about the application? What are you making?

 

[hbard21]

thank you mdjenson, that actually does help a lot, however my wire is going to be coiled. will this effect the numbers given in that site?

and unfortunately berkeman i am not legally allowed to divulge much more information about the application of the device. All i can really say that it is used to heat a liquid that is being run through the coil. if there is something specific you are wondering that would make helping me more clear, please feel free to ask and hopefully i can tell you to receive assistance.

 

[mdjensen22]

Glad that helps - I have no idea in terms of the effect of coiling the wire. All of my applications have been straight wire. Sorry...

I was thinking a little more about this, and one thing to keep in mind is your current draw. I'm not sure what type of battery/batteries you are planning on using, but you will most likely be pulling a lot of juice - the discharge rate for the battery is something to pay attention to.

Also, be aware that your battery voltage may drop as your batteries discharge - this will alter your temperature.

If I may make a suggestion, I would recommend using a current limited bench supply for your initial development work. This will let you play around with various voltages without going through so many batteries.

 

[hbard21]

thanks again. yeah, the whole battery issue is also a big concern for this project.

i will run some tests and hopefully everything goes well. thanks so much!