Seoul National University

Other

Doyub Kim

Hyeong-Seok Ko

Oh-Young Song

A simple and efficient method for simulating dispersed bubble flow is provided. Instead of modeling the complex hydrodynamics of numerous small bubbles explicitly, the method approximates the average motion of these bubbles using a continuum multiphase solver. The subgrid interactions among bubbles are computed using a new stochastic solver. Using the proposed scheme, complex scenes with millions of bubbles can be simulated efficiently.

Method for simulating dispersed bubble flow

A method for simulating the stretching and wiggling of liquids is provided. The complex phase-interface dynamics is effectively simulated by introducing the Eulerian vortex sheet method, which focuses on the vorticity at the interface and is extended to provide user control for the production of visual effects. The generated fluid flow creates complex surface details, such as thin and wiggling fluid sheets. To capture such high-frequency features efficiently, a denser grid is used for surface tracking in addition to coarser simulation grid. A filter, called the liquid-biased filter, is used to downsample the surface in the high-resolution grid into the coarse grid without unrealistic volume loss resulting from aliasing error.

Method for simulating stretching and wiggling liquids

A new constrained interpolation profile method, which is stable and accurate but requires less amount of computation, is provided. CIP is a high-order fluid advection solver that can reproduce rich details of fluids. It has third-order accuracy but its computation is performed over a compact stencil. A novel modification of the original CIP method that fixes all of the above problems without increasing the computational load or reducing the accuracy is provided. The proposed method brings significant improvements in both accuracy and speed.

Semi-Lagrangian CIP fluid solver without dimensional splitting

The method provides a new fluid simulation technique that significantly reduces the non-physical dissipation of velocity using particles and derivative information. In solving the conventional Navier-Stokes equations, the method replace the advection part with a particle simulation. When swapping between the grid-based and particle-based simulators, the physical quantities such as the level set and velocity must be converted. A novel dissipation-suppressing conversion procedure that utilizes the derivative information stored in the particles as well as in the grid points is developed. Through several experiments, the proposed technique can reproduce the detailed movements of high-Reynolds-number fluids, such as droplets/bubbles, thin water sheets, and whirlpools. The increased accuracy in the advection, which forms the basis of the proposed technique, can also be used to produce better results in larger scale fluid simulations.

Growing community of inventors

Seoul, South Korea

Doyub Kim