濡れ性の悪い平面壁に衝突する単一気泡の挙動

抄録

The behavior of a bubble in collision with a poor wettability plate was experimentally investigated. Equilibrium shape of a sessile bubble beneath a horizontal plate was determined from the condition minimizing the bubble energy being the sum of the potential energy and the surface energy. Rebound motion of an impacting bubble was observed for a poor wettability plate as well as good wettability plate. For the poor wettability plate, small bubbles (d_B≈ 2×10^-3m) attached to it up to an inclination angle θ_p of 60°C. Large bubbles being attached to an inclined plate of poor wettability ascended along the plate. The limit between stopping and sliding of an attached bubble was determined from a force balance including the advancing contact angle θ_a and receding contact angle θ_r. There is not difference of bubble rising velocity between two flat plates.