Abstract
Optically induced thermal Marangoni instability in irradiated transparent liquid films on absorbing solid substrates is investigated numerically, where the effects of optical interference between light waves reflected from the gas-liquid and liquid-solid interfaces are taken into account. When a film is exposed to uniform irradiation, the film stability is strongly affected by the energy reflectance that fluctuates with the film thickness, so that the stability varies periodically with the thickness. When a film is exposed to weakly nonuniform irradiation, the behavior of the film is affected not only by the nonuniformity but also by the stability for uniform irradiation with the mean light intensity. While a nonuniformly irradiated film that is stable for uniform irradiation is deformed but remains in the neighborhood of the initial state, a similarly irradiated film that is unstable for uniform irradiation evolves in a manner similar to phase separation behavior observed in uniformly irradiated films.
