Fabulous, flowing, and folding fountain of chocolate —Lyes Kahouadji (Imperial College London)

We present a three dimensional direct numerical simulation of a heated chocolate fountain flow where the geometrical structure is built from primitive geometrical objects using a state distance function (positive for fluid and negative for solid). We use physical properties of melted chocolate (40°C) flowing and ambient atmosphere (20°C). We solve both Navier-Stokes and the thermal energy equation in the context of a front-tracking based multiphase method and fluid structure interaction. The left-hand half is the temperature field. The right-hand half is the streamlines on a vertical slice. The parallelization of the code is based on algebraic domain decomposition, where the velocity field is solved by a parallel GMRES method for the implicit viscous terms and the pressure by a parallel multigrain method and the communication across process threads is handled by MPI message-passing procedures.