Overview
NaSt3DGPF is an implementation of a solver for the incompressible NavierStokes equations in three dimensions. It allows the realistic simulation of twophase flows with free surfaces. NaSt3DGPF exhibits the following features:
 Simulation of twophase flow is implemented with a levelset approach
 Surface tension forces are implemented with the continuum surface force method
 Simulation of turbulence is based on a largeeddy approach (Smagorinsky model)
 Convective terms can be discretized with higher order ENO and WENO schemes
 spatial discretization by 2nd order finite differences on a rectangular, nonuniform, staggered mesh
 convective term: higher order upwind schemes (VONOS, SMART), central differences (2nd order), simple upwind (1st order)
 2nd order AdamsBashforth scheme for the time discretization
 boundary conditions: slip, no slip, periodic, inflow, outflow (Neumann, convective, natural)
 (passive) advectiondiffusion transport model for concentration of species
 Boussinesq advectiondiffusion transport model for temperature
 handling of complex geometries by a simple cell decomposition/enumeration technique
 BiCGStab and SOR iterative solver for pressure Poisson equation (lexicographical, redblack, colored redblack)
 parallelization by means of 3D domain decomposition with good communication/work ratio heuristics
 parallelization based on MPI
 implemented in C++
 various import/export formats, including architecture independent ones and for the VTK graphics library
 macro language for easy problem description
Much emphasis is laid on the point that also complex problems, such
as flows around complicated geometries, can be defined in a clear
and easy way to obtain numerical results rapidly. To this end, there
is a simple macrolanguage with a few but powerful and meaningful
keywords to describe the flow configuration. This allows the user
to
 build complex geometries by union, intersection, subtraction
of CSG (Constructive Solid Geometry) primitives using shape
parameters independent on the discretization
 describe the computational mesh in a simple way
 define various parameters, e.g. Reynolds number, stopping
value for iterative solver, upwind parameter, etc.
Have a look at the Gallery for movies of simulation results obtained with NaSt3DGPF.
A list of projects which use NaSt3DGPF as the primary toolkit for numerical simulation of twophase flow is available here.


Licensing
For nonprofit usage, the software package NaSt3DGPF can be obtained here after registration.





