Manipulating Gas Micro-Volumes with Submerged Meshes of Controlled Wettability

The interaction of rising gas bubbles with submerged air-repelling and air-attracting surfaces is useful for a number of applications, and a number of studies exist in that regard. However, little attention was given to the study of the interaction of bubbles with submerged metal meshes. The present work demonstrates the possibility of employing submerged metal meshes with super air-attracting/repelling properties to manipulate micro-volumes of air, in the form of bubbles, rising with terminal velocity in water. Super-aerophobic meshes are observed to selectively allow the passage of an air bubble depending on the mesh pore-size and the bubble equivalent diameter, while super-aerophilic meshes can be used to reduce or amplify the volume of a stream of incoming bubbles. Finally, a wettability pattern is imparted on the top and bottom surfaces of the mesh to control the size of the outgoing bubble, and an empirical relation is proposed for the predicting its volume.