Effect of angle in removing proteins or bacteria on a tilted surface using air bubbles

Our work investigates cleaning surfaces coated with protein solutions or bacterial biofilms using continuous collisions and sliding air bubbles in an aqueous medium. Air bubbles between 0.5-1 mm in radius perform best when tilted at 20-25 degrees with respect to the horizontal plane. Based on our model, the interplay between the steady sliding speed and the steady film thickness between the bubble and the surface yields the best cleaning at 22.5 degrees. The technique offers a safe and environmentally friendly way of cleaning fresh agricultural produce without damaging it or reducing its freshness period.