The Role of Thermoviscous and Thermocapillary Effects in the Cooling and Gravity-Driven Draining of Molten Free Liquid Films

We theoretically considered two-dimensional flow in a vertically aligned thick molten liquid film to investigate the competition between cooling and gravity-driven draining, which is relevant formation of metallic foams. Molten films cools as it drains, losing its heat surrounding colder air substrate. extended our previous model include non-isothermal effects, resulting coupled non-linear evolution equations for film’s thickness, extensional speed temperature. The coupling effect was via constitutive relationship temperature-dependent viscosity surface tension. This parameterized by transfer coefficients at film–air free film–substrate interface, Péclet number, viscosity–temperature parameter slope linear tension–temperature relationship. A systematic exploration space revealed that low numbers, increasing coefficient gradually reducing with temperature conducive could slow down draining thinning film. on observed be more effective lower where tension gradients lamella region opposed flow. At higher though, tended enhance region, dramatic later stages.