Multiphase Modelling of Thin Film Flow Over the Vertical Plate Under Gravity in Pseudo-Laminar Region

In many engineering applications, such as in compressors, evaporators, and boilers, wavy film flow acts as a heat transfer barrier. Numerous researchers used long wave approximation and linear stability analysis to characterize the wavy flow. It is still necessary to study the film flow over the vertical plate in the pseudo-laminar region using numerical simulation and analytical models such that varying heat transfer coefficients with time and space can be obtained later. In the current study, we developed an analytical model that depicts the distribution of forces as a function of the film thickness and change in wave amplitude with time and space, variation of film velocity profile, and wall shear stress along the plate. We also performed a multiphase VOF simulation using ANSYS Fluent for two films free stream Reynolds number 2000 and 4000, several parameters including velocity profile, variation in film thickness along the plate length and time, variation in film Reynolds number and wall shear stress along the plate length, were obtained. Film thickness and Reynolds number data from the simulation show a 1.13% average error with the Kapitsa average film thickness equation.