TOOTHPASTE

The Viscoplastic CFD App for MATLAB

TOOTHPASTE is a finite-element code for a broad class of small to medium-scale flow problems in computational fluid dynamics. It is specifically designed for simulations of viscoplastic fluid flows, but Newtonian and generalised Newtonian fluids are included as special cases.
This code is under active development. Several additional features have already been implemented upstream and will be released in due course.
What this app does
* Available constitutive models: Newtonian fluids, generalised Newtonian (power-law) fluids, Bingham fluids, Casson fluids, Herschel-Bulkley fluids
* 1.5D flow (unidirectional through a 2D cross-section) or fully 2D flow
* Coordinate system: Cartesian
* Time-dependence: steady state
* Boundary conditions: Dirichlet and/or Neumann (do-nothing)
* Discretisation: Bercovier-Pironneau elements in 2D, linear finite elements in 1.5D
* Viscoplasticity: genuinely nonsmooth treatment with no regularisation or smoothing, solution of the convex optimisation problem with a state-of-the-art accelerated dual proximal gradient method (FISTA*)

What this app does not (currently) do

* Flow problems for fluids governed by constitutive models other than those listed above, or turbulent flows
* 2.5D or 3D flow problems
* Polar, cylindrical or other coordinate systems
* Time-dependent problems (scheduled for a future release)
* Fully developed or symmetry boundary conditions (scheduled for a future release)
* Higher-order elements, finite differences or finite volumes
* Regularised formulations to approximate viscoplastic behaviour with generalised Newtonian laws

TOOTHPASTE is FLOSS (free/libre open source software)

Please refer to the licence text for details. The vast majority of this code is also compatible with GNU Octave. The postprocessing module of this program and the matrix assembly routine for the P1-iso-P2 element, however, presently rely on plotting and mesh-refinement commands from the MATLAB PDE Toolbox.

For further details, please refer to the HTML-file in the documentation folder.