Dynamics of binary solution droplets of an ionic liquid and water impinging on a heated porous surface

Abstract

The dynamics of a binary solution droplet of ionic liquid and water on heated brass porous surfaces were studied. A comparison was made between the droplet dynamics on the porous and impermeable surfaces. An increasing spreading diameter for the binary solution droplets on the impermeable surfaces was observed, while this was not found on the porous surfaces. The time required for the droplet to penetrate the porous surfaces was significantly shorter than that for the droplet to evaporate completely from the impermeable surfaces. During the process of droplet infiltration into the porous medium, the droplet evaporation could be neglected. A higher Weber number and a higher surface temperature resulted in a higher liquid penetration rate. A linear and polynomial change in the residual volume for the binary solution and water droplet, respectively, on the porous surfaces over time was observed.