Tranvel Instabilities in Lateral Heating

Abstract

We study the convective motion forced by lateral heating on a liquid layer. The movement is caused by two forces: buoyancy and thermocapillarity on the free surface, which is open to the air. As soon as a temperature gradient is imposed along the liquid layer, the fluid begins to move. When a certain threshold of the temperature di erence is attained, this flow destabilizes and oscillations appear. We have performed an experiment to characterize the thermocapillary waves in a rectangular container whose dimensions can be continuously changed. This way, we are able to investigate how boundaries a ect the threshold for the instability, as well as their consequences on other features of the waves.