filename : Pfa09.pdf entry : inproceedings conference : SIGGRAPH 2009, Yokohama, Japan, 16 - 19 December 2009 pages : 121:1 - 121:10 year : 2009 month : December title : Synthetic Turbulence using Artificial Boundary Layers subtitle : author : Tobias Pfaff, Nils Thuerey, Andrew Selle, Markus Gross booktitle : SIGGRAPH '09: ACM SIGGRAPH 2009 papers location : Yokohama, Japan ISSN/ISBN : editor : publisher : ACM Press / ACM SIGGRAPH publ.place : volume : 28 issue : 5 language : English keywords : turbulence, fluids, vortex particles abstract : Turbulent vortices in fluid flows are crucial for a visually interesting appearance. Although there has been a significant amount of work on turbulence in graphics recently, these algorithms rely on the underlying simulation to resolve the flow around objects. We build upon work from classical fluid mechanics to design an algorithm that allows us to accurately precompute the turbulence being generated around an object immersed in a flow. This is made possible by modeling turbulence formation based on an averaged flow field, and relying on universal laws describing the flow near a wall. We precompute the confined vorticity in the boundary layer around an object, and simulate the boundary layer separation during a fluid simulation. Then, a turbulence model is used to identify areas where this separated layer will transition into actual turbulence. We sample these regions with vortex particles, and simulate the further dynamics of the vortices based on these particles. We will show how our method complements previous work on synthetic turbulence, and yields physically plausible results. In addition, we demonstrate that our method can efficiently compute turbulent flows around a variety of objects including cars, whisks, as well as boulders in a river flow. We can even apply our model to precomputed static flow fields, yielding turbulent dynamics without a costly simulation.