I need to regulate the temperature of the surface of a tube of aluminium. The tube is used as a mandrel for composite molding/curing, so the target temperature is below 100C.
Currently, there is no type of heating element attached to the tube. I have done a little bit of research, and these are some of the possibilities I found:
- Peltier module. Its hot side would be glued with thermal grease to some areas of the tube, the cold side would be brought to room temperature with a heatsink + fan.
- Resistive heating element. Nichrome wire would be wrapped around the tube and heat it by thermal conductivity. However, it seems to be challenging to electrically isolate the wire from the aluminium tube.
- Joule-heating the tube. Voltage between the extremities of the tube would heat it by Joule effect. The problem is the current requirement is huge, since the tube resistance is low.
- Hot air. It is simple to setup up with a fan and heating elements, but the heating would not be uniform due to convection currents.
I am looking to some answers about:
- The Peltier module is widely used to cooling applications, do they have a down-side when used the opposite way, to heat things up?
- Could the nichrome wire be isolated electrically but not thermically easily?
- Would it be easier to switch to a steel tube and heat it by induction? By coiling the tube and applying AC current?