Laser-induced surface-tension-driven flows in liquids

High-intensity, short-pulse laser radiation incident on the free surface of an absorbing dielectric liquid results in heating that can alter the liqui d surface tension, causing Marangoni convection. This flow can dominate the transport of thermal energy in the liquid. In this work, both a scaling an alysis and a full numerical simulation of the governing equations are perfo rmed. A thermal mechanism is proposed as the driving force for these flows. The dependence on beam size and temperature increase in the liquid is inve stigated, with good agreement found among the scaling analysis, numerical s imulations and experimental data obtained from a previous study. The import ance of natural convection and thermal conduction on the fluid-thermal tran sport was assessed numerically, with both found to be negligible for this l iquid-laser system. Velocity and temperature profiles at the liquid surface are also discussed. (C) 1998 Elsevier Science Ltd. All rights reserved.