Oil temperature as a function of water temperature

jonlg_uk

Hi imagine I have a sphere of silicone oil in a sealed metal container. I then fully submerge the container in a bath of ice and water. This is what I have done.

The bath temperature remains at just below zero degrees. However the silicone oil temperature remains around 0.15degrees C. Despite both temperature probes being calibrated.

Any ideas gang?

I thank you in advance.

Chestermiller

I assume the silicone oil is less dense than the water. What is mechanically holding the sphere down, and can there be a heat leak through whatever is holding the sphere down? Can there be a heat leak through the thermocouple wire? Is 0.15 degrees that significant?

jonlg_uk

This is what I thought the problem might be. The sphere is held in place by in all directions by metal pegs that are welded onto the inside wall of the outer container (the container that holds the ice and water solution). However the whole system sits in an environmental chamber that is set to -1 degrees C (this has been calibrated aswell).

Could thin thermocouple cable really be responsible for heating the silicone oil temp up by this much?? The cable does run out of the chamber and into to the "outside world", where the room temperature is held around 21 degrees C.

I am not sure....the specific heat capacity of silicone oil is less than water, I don't understand why it's temperature is not the same as the ice and water?