Version 2020.4

Released: TBD

Highlights: Windows GPU, 3D, Non-Newtonian flow

  • WIP: Calibration for 3D problems
  • WIP: Added BiCGStab solvers for the velocity.
  • WIP: BDF2 velocity implicit solver for 2nd order.
  • WIP: Windows GPU support.
  • WIP: Non-Newtonian models.
  • WIP: Optimization of 3D collision detection fluid with geometry.
  • WIP: Fixed outputting of the bodies forces.
  • WIP: Stabilisation of linear solvers due to floating precision, by exactly computing the residual Nth iteration.
  • WIP: Adding 2nd order div(u) source term in the pressure Poisson equation

Version 2020.3

Released: 2020-11-16

Highlights: Windows, implicit velocity solver

  • Pressure gradient limiter to stabilise non smooth pressure fields.
  • Stabilised/improved source term for the pressure Poisson equation.
  • Implicit solution to the velocity with Jacobi solver and BDF1, stable high viscosities.
  • Improved Jacobi solver performance by average value of 7%.
  • Explicit curvature estimation at the free surface.
  • Surface tension force through pressure Dirichled b.c. (using curvature and Laplace jump).
  • Windows CPU support. GPU yields strange driver errors not experienced on Linux.
  • The domain acceleration may be imposed through timeline of positions, velocities or accelerations.
  • Fluid can be initialised in separate spaces by specifying multiple sources of flooding.
  • Added real-time colourisation by point’s IDs.
  • Added real-time colourisation of free-surface points.
  • Rendering of too fast simulations is limited to 60 FPS, to avoid losing performance on CUDA -> OpenGL transfer.
  • Added and tested Mohr-Coulomb non-Newtonian model.
  • Made research license a bit more flexible.

Version 2020.2

Released: 2020-05-10

Highlights: GPU, FEM, moving bodies

  • Enabled CUDA backend to run simulations on the GPU.
  • The movement of bodies may be imposed through timeline/keyframes of positions or velocities.
  • Smooth interpolation of imposed movement of bodies in time, using Piecewise Cubic Hermite Interpolating Polynomial (PCHIP).
  • Imposed body oscillations (along vector, or rotating along axis) are superposed to the movement, by using “impose_oscillation” input.
  • No more triangle soups, meshes now use connectivity information. This enables deformations, and easy orientation transformation.
  • Import surface meshes from OBJ, OFF or STL file formats. For STL (triangle soup) file format, connectivity is built upon loading.
  • Warning message is shown for users that have a too old GPU, that cannot view results in real-time.
  • Fluid-structure interaction using preCICE. Rhoxyz can be coupled with an external FEM solver. Tested using CalculiX solver.
  • Bodies marked using: “output_force”: true, export resultant force and torque acting on the body to a CSV file, each time step.

Version 2020.1

Released: 2020-02-15

Highlights: Initial public version