Rotating Convection

Just playing around

This experiment was originally a student experiment used to demonstrate Mantle convection. The rotating system element of the experiment was a bit of playing around unrelated to the original experiment.

We thus started the experiment without much forethought, and used a small homemade cooling device made to fit on the rotating table.

The steam train engineer

The small cooling device was made with a Peltze device, and it was too weak to generate a sufficient temperature gap. We ended up having no choice but to maintain the temperature by dropping small ice cubes the cold water while keeping an eye on the thermometer. As the temperature gap grew, the pace of ice cube dropping also increased, and this dropping of the ice cubes in rhythm with the rotation of the rotating table was somehow reminiscent of the engineer of a steam train.

 

A lucky hit

The parameters that could be used for experimentation with this apparatus were limited to a uninspiring sphere close to the critical Rayleigh numbers. In the 1990's, experiments at much higher Rayleigh numbers have been actively carried out, so in comparison, our experiment was a little behind the times. Since we never intended to carry out experiments on the bleeding edge, I suppose this can't be helped.

However, as I researched related theses during the course of the experiment, I discovered that a number of issues that I thought would have been resolved years ago were actually still unresearched. Even in a simple experiment like this, we still managed to find some new facts.

If I had have been reading the latest theses, I probably would have never bothered with an experiment under these parameters.