Numerical observation and analytical formulation of droplet impact and spreading around the thin vertical cylinder

Abstract

The dynamic characteristics of a water droplet impact on a thin vertical dry solid cylinder are delineated numerically. Finite volume-based axisymmetric simulations are carried out by employing the volume-of-fluid method to predict complex hydrodynamic behaviors. To simulate the present computational work, the conservation equations of mass, momentum, and volume fraction are solved. The droplet surface undergoes a continuous deformation during impact to the thin cylindrical target by resulting in various crucial stages: free fall, hitting, cap formation, encapsulation, uncovering, and detachment. The range of cylinder-to-droplet diameter ratio ( Dc/ Do) is considered to be from 0.13 to 0.4 for the present computational study to observe different deformation patterns of the droplet. The influence of contact angle ( θ), Dc/ Do, We, Oh, and Bo on the maximum deformation factor is elucidated from the numerical results. The findings show that the maximum deformation factor increases with the increasing We and the reducing contact angle. An analytical model has been formulated to elucidate the maximum deformation factor, which shows an excellent agreement with the numerical results. Furthermore, a correlation was developed to predict maximum deformation factors in terms of θ, Dc/ Do, We, and Oh, which operates exceptionally well within ±1% of the computational data.