Is there some sort of heat conductive wave?

[Heros_iragorri]

Hello, i am new at the forum and i hope i can help and get helped so we can move forward in our projects/jobs/studies. I also ask please to correct any gramatical or vocabulary mistake, since i am still learning english.

Now to the actual problem.
I am already building some kind of epoxy resin curing device, the important thing in this is that it generates a very constant temperature surface, constant in space and time.

The device is made out of aluminium and is internally heated by oil at about 200 celcius, the fluid temperature is monitored by a variable resistance sensor, and activated by an electronic comparator circuit, i am also constantly sensing the surface temperature and turn on or off the oil heater acording to this.

The issue is that there is a big delay between the heater activation and the surface getting the target temperature(aprox 20 seconds delay) and that creates some sort of resonant frecuency in the temperature domain. Also creating overheating in some points of the system, and very irregular surface temperature in time domain.

My real question is if there is a wave kind of behavior of these heat going into the piece, if so, what is the speed of that wave? is that a constant speed wave?My wish is to know that for somehow predict and slow down the "resonance". I understand that there is a formula that from given temperature gradient, conductivity and area can calculate power, but i think that that's for time going to infinity.

Thanks.

 

[rootone]

You could probably introduce a small computer to the setup that can estimate ahead when the temperature will have fallen to the critical level.
It would then be able to trigger the reheating slightly ahead depending on how fast the temperature is falling.

 

[Tom.G]

That is a common problem and can be improved but it is not real easy. Look up PID controller on Google, over 5 000 000 hits.
https://www.google.com/?gws_rd=ssl#q=pid+controller