Travel Instabilities in lateral heating

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 difference 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 affect the threshold for the instability, as well as their consequences on other features of the waves.