title: A deformable surface model for real-time water drop animation.
abstract: A water drop behaves differently from a large water body because of its strong viscosity and surface tension under the small scale. Surface tension causes the motion of a water drop to be largely determined by its boundary surface. Meanwhile, viscosity makes the interior of a water drop less relevant to its motion, as the smooth velocity field can be well approximated by an interpolation of the velocity on the boundary. Consequently, we propose a fast deformable surface model to realistically animate water drops and their flowing behaviors on solid surfaces. Our system efficiently simulates water drop motions in a Lagrangian fashion, by reducing 3D fluid dynamics over the whole liquid volume to a deformable surface model. In each time step, the model uses an implicit mean curvature flow operator to produce surface tension effects, a contact angle operator to change droplet shapes on solid surfaces, and a set of mesh connectivity updates to handle topological changes and improve mesh quality over time. Our numerical experiments demonstrate a variety of physically plausible water drop phenomena at a real-time rate, including capillary waves when water drops collide, pinch-off of water jets, and droplets flowing over solid materials. The whole system performs orders-of-magnitude faster than existing simulation approaches that generate comparable water drop effects.
authors.affiliation: State Key Laboratory of CAD&CG, Zhejiang University, Hangzhou, Zhejiang, China. yizhongzhang@zju.edu.cn
authors.forename: Yizhong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Huamin
authors.initials: H
authors.lastname: Wang
authors.forename: Shuai
authors.initials: S
authors.lastname: Wang
authors.forename: Yiying
authors.initials: Y
authors.lastname: Tong
authors.forename: Kun
authors.initials: K
authors.lastname: Zhou