Fluids and solids
Simulating fluids is very challenging as fluids may assume a large number of dynamical states, e.g., resting at hydrostatic pressure, transmitting force and flowing through pipes and valves, complex vortex patterns, small wave ripples, waves breaking on the shore, chaos and turbulence in the wake of a moving airplane.
There are also complex and non-Newtionian fluids, e.g., anisotropic, elastic, viscous and plastic with complex dependency between flow rate and stresses. Examples of complex fluids are biological fluids (blood), rubberlike liquids, molasses, glass, sand and soil. If the fluid particles always stay close to its neighbours we refer to these materials a solids.
We use and develop mesh-free methods, e.g., Smooth Particle Hydrodynamics (SPH) and Moving Least Squares (MLS), for complex 3D simulations with free surfaces and strong coupling with mechanical parts and moving boundaries. In particular, we focus on realtime visual interactive simulation for training, education, entertainment and on off-line but time-efficient engineering simulations of large-scale systems with complex geometries.
Our key results include a unified constraint-based approach for particle and rigid body based modelling of fluids, solids and jointed mechanical systems that allows large time-step simulation, and efficient parallel and direct, iterative and hybrid solvers for the corresponding mixed linear complementarity problem (MLCP).
- Meshfree elastoplastic solid for nonsmooth multidomain dynamics, J. Nordberg, M. Servin, submitted (2015). pdf
- Constraint fluid, K. Bodin, C. Lacoursière, M. Servin, IEEE Transactions on Visualization and Computer Graphics, 31 Jan. 2011. IEEE computer Society Digital Library. IEEE Computer Society, <http://doi.ieeecomputersociety.org/10.1109/TVCG.2011.29>. pdf
- Fast and stable simulation of granular matter and machines, C. Lacoursière, M. Servin, A. Backman, DEM5 - The Fifth International Conference on Discrete Element Methods, London 25-26 Aug (2010). pdf
- Interactive simulation of elastic deformable materials, M. Servin, C. Lacoursiére and N. Melin, SIGRAD 2006 Conference Proceedings, Skövde, Sweden, (2006), ISBN 91-85643-17-3. pdf