Dewetting regimes of condensation droplets in a microgroove

This paper describes a numerical investigation of the groove-embedded droplet dewetting process, namely the spontaneous transition from the Wenzel state to the Cassie state, using the multiphase lattice Boltzmann method. Numerical simulations are employed to reproduce the dynamic behaviors of extension, squeezing, rupture, and ejection of condensation droplets in a groove, allowing us to examine how the groove geometry and wettability affect the dewetting process. Our results identify three dewetting regimes, namely retention, partial dewetting, and complete dewetting. As the groove aspect ratio and hydrophilicity decrease, the dewetting regime changes from retention to partial dewetting, and then to complete dewetting. The partial dewetting and complete dewetting are two effective ways for droplet removing. In particular, a groove sidewall with enhanced hydrophobicity is desirable to stimulate the dewetting process.