A Sharp-Interface Cartesian Grid Method for Computations of Droplet Impact and Spreading on Surfaces of Arbitrary Shape

摘要

A sharp-interface treatment of the solid-fluid boundaries is combined with the Ghost Fluid Method (GFM) to simulate interactions between droplets and solid surfaces. All interfaces are represented by level sets. Application of contact angle conditions at the junction between the solid-fluid and fluid-fluid boundaries is fairly challenging in the level-set approach. In the VOF approach the contact angle can be imposed by reconstructing the partial volume in the fluid-fluid interface cell that lies adjacent to the solid surface such that the reconstructed surface assumes the specified contact angle with respect to the solid surface. In the Lagrangian moving mesh approach the mesh node that lies on the solid surface can be moved to apply the desired angle. An alternative approach based on a local level-set reconstruction has been modified and advanced in the present work. Additionally, the method is designed to enable simulations of droplet spreading on arbitrarily shaped solid surfaces. The results are compared with experimental as well as numerical results.