No abstract

The onset of Marangoni convection in an initially isothermal, quiescent fluid layer experiencing evaporative cooling from above is analyzed theoretically. For this system, the stability analysis on regular cell modes is conducted, based on the linear stability theory, the energy method, and their modifications. The stability equations are derived and the critical time to mark the onset of convection (τ c ) is obtained, as a function of the Marangoni number (Ma) and the Prandtl number (Pr). The linear stability theory predicts more-stable conditions than the energy method. The present results show that τ c decreases as Pr increases for a given Ma value. The present predictions are compared with the available experimental data of propanol.

The onset of buoyancy-driven convection caused by gas absorption through the upper free boundary of an initially quiescent, horizontal liquid layer is analyzed under linear theory. It is well-known that convective motion sets in when the Rayleigh number (Ra) exceeds a certain value. In this study, the critical conditions to mark the onset of convective instability are analyzed using the dominant mode method and frozen-time model for large Ra values. The results are compared with those from the propagation theory and also the amplification theory. The dominant mode method yields the stability criteria, which agree well with those from the propagation theory. Therefore, the latter results are compared with available experimental data. It is shown that the initiated instabilities grow until detected experimentally and the upper free interface often behaves similar to a rigid one.

Articles you may be interested inStability analysis of ultrathin lubricant films via surface energy measurements and molecular dynamics simulations J. Appl. Phys. 97, 10P302 (2005); 10.1063/1.1849073 Surface morphology and molecular conformation for ultrathin lubricant films with functional end groups

No abstract