where 
what 
details 
user interface 
all 
 one look & feel for geometry, meshing, physics and analysis
 easy to learn
 instant help available: click ‘?’ and move cursor over the item that you have a question about
 you do not see more than you need
 we don't ask you to stare at 1000 buttons if only a few of them are relevant at that point
 after selecting models for a domain, down the road you will only see input options for those models
 options likely to remain unchanged for a longer time are available under preferences (and can be sticked to the current case)

manual 
all 

geometry 
length units 
meter, micrometer, millimeter, centimeter, decameter, hectometer, kilometer, microinch, milliinch, inch, feet, miles 
parameters 
by mathematical expressions 
building actions 
 new primitives of many kinds, polyprimitives, delete, copy (with optional copying of settings like meshing settings), move (with possible deformations), sweep, booleans, split, boundary layer (to prepare for boundary layer meshing), fillets & chamfers, import of IGES and STEP files.
 arguments of these actions can be mathematical expressions which depend on geometric parameters, current point positions etc.

recipe 
 all actions are listed in a geometric recipe text
 can be easily edited and reevaluated (directly in the GUI or in the geometry file)
 ‘slow evaluation’ available for stepwise inspection of the building process

easy handling 
 undo & redo
 select primitives by picking
 tools to search & locate primitives, get exact distance between 2 points, hide part of the geometry

positioning of domains, materials and boundaries 
 geometry & meshing is physicsfree
 by easy clicking in tables (also for many primitives at once), or by picking
 automatic detection of primitives that need a boundary definition
 idem for ‘splitters’: boundaries between 2 different domains

meshing 
element size 
 steerable by 1 number for ‘default’ line meshing setting
 can be overruled for each line by mathematical expression

lines 
uniform element size, or grading in 1 of 2 directions, or bump grading 
surfaces 
 triangular
 quaddominated
 sweep meshing, for 3 or 4sided surfaces

bodies 
 tetmeshing
 quaddominated
 sweep meshing, for bodies with shapes that enable this, like any body made by a sweep geometry action

nonmatchings 
 on planar parts of the geometry, nonmatching connections between 2 surfaces or 2 bodies are allowed
 without noticeable degradation of the solver

Gmsh meshes 
import of Gmsh meshes is possible

files 
 geometry & meshing (a)
 mesh (a or b)
 case (a)
 results (a or b)

 a: ASCII, b: binary
 ASCII geometry & meshing and case files
 have a simple syntax
 give a clear overview of your definitions
 can be edited in a plaintext editor and reloaded

physics: thickness and crosssection fields 
 axisymmetry
 sphericalsymmetry

 you can scale 2D meshes by the ‘thickness field’, defined by a mathematical expression. If this is for instance ‘2*Pi*Z’ for meshes in the XY plane, you can conduct axisymmetric calculations
 not yet available for linear elasticity

physics: models 
flow 
 NavierStokes, both segregated and fully coupled algorithm
 Darcy/porous flow
 potential flow
 imposed flow, for statically moving parts like a moving belt/rotating wheel
 buoyancy, both Boussinesq and fulldensity approach
 userdefined forces by mathematical expressions

turbulence models (RANS) 
 SpalartAllmaras model
 Shear Stress Transport model
 with or without wall functions

heat 
temperature equation 
radiation 
 Discrete Ordinates model
 several Sn ordinate sets (modified Balsara Sn2 to Sn12)

solutes 
 any number of userdefined solutes
 useable as tracer, pollutant species etc.

electromagnetism 
 electrostatics
 DC current
 Joulean heat release if DC combined with heat model

linear elasticity 
 displacementpressure formulation
 thermal stresses if combined with heat model
 fully implicit finite volume algorithm; if all properties and conditions do not depend on the solution and no damping is applied, convergence in 1 iteration

anisotropy 
 permeability for Darcy flow
 heat conductivity
 solute diffusivities
 electric conductivity and electric permittivity

physics: user variables 
 singlevalued
 scalar fields
 vector fields

 can be set by mathematical expressions, may depend on location, any solution field, time, other user variables etc.
 singlevalued user variables can have a location (e.g. a boundary) and an operator (e.g. the max of the evaluated expression on that location)
 usable for
 parameters
 monitoring
 output requests, like the drag on a boundary, or the total heat generation on a domain
 fields defined by analytically known solutions to check the numerics
 fields in nonSI units
 etc. etc.
 when defined before the calculation: updated each iteration
 when defined after the calculation: can directly be evaluated using the current results

physics: properties and conditions 
material properties, sources, start values 
 can be set by mathematical expressions
 may depend on location, any solution field, user variable values etc.
 this enables you to define your own multiphysics

boundary conditions 
 can be set by mathematical expressions, may depend on location, surface orientation, any solution field, user variable values etc.
 on separations between 2 domains (‘splitter boundaries’), coupling of the solution is possible
 consult the manual for the available boundary condition types per model

physics: numerics 
space discretisation 
 colocated cellcentered finite volume method
 optional TVD for convective fluxes
 fully conservative, when converged balances add up to 0 (also on coarse meshes)

time discretisation 
 1or 2step Backward Difference Formula for flow, heat etc.
 for linear elasticity: Bossakalpha method

model iterations 
 each big iteration constitutes a loop over all models that are activated (‘segregated approach’)

damping 
 settable for many fields, can be modified while the calculation runs to directly see the influence on the XY residuals plot
 can often remain 0 for calculations on ‘nottoobad’ meshes

linear solvers 
 PARDISO direct solver
 iterative solvers from the Paralution library
 stateoftheart iterative solvers
 default settings are good, but combination preconditioner & solver is chooseable
 optionally with use of CUDA GPU computing (for larger NVIDIA graphical cards)

parallel 
 both matrix assembly and solve steps parallelised for use on multicore CPU’s
 number of used cores/threads chooseable

result analysis 
XY plots 
 convergence plot shows the residuals
 user defined graphs for field values on straight lines
 singlevalued user variables versus iteration number, or versus time

3D graphics 
 contours: element wise or smoothed, isolines, banded or isosurfaces
 vectors
 tensors (e.g. stress or strain tensor)
 streamlines
 animation of transient results, image files can be saved for making movies in a 3rd party program
 export to Paraview (Ensight Gold format) for more advanced visualisation
