Instabilities of Numerically Computed Thermocapillary Flows in Liquid Bridges at Medium Prandtl Numbers

Abstract

The instabilities of the thermocapillary flows in cylindrical liquid bridges are investigated numerically by employing a finite volume approach to solve the complete Navier-Stokes equations accompanied by appropriate boundary conditions on the free surface, which model the surface tension effects. The influences of Marangoni number, aspect ratio A and gravity on the computed spatio-temporal structures of the thermocapillary flow are emphasized. The structures associated with high Marangoni number regimes are analyzed by using specific tools of the nonlinear dynamics: temperature signal, power spectrum, first return maps and Poincare maps.