Abstract
An optical grid line method with image correlation analysis processor has been developed for study of the kinetics of buoyantthermocapillary convection，it gives out the information of liquid free surface of buoyant-thermocapillary convection in a rectangular cavity. In the present paper, the free surface deformations of the thin liquid layer and the thick liquid layer have been discussed and compared. The present experiment results prove that surface deformation is related with temperature gradient and the thickness of liquid layer. In other words that surface deformation depends on capillary convection and buoyancy convection.
