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)
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manual |
all |
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geometry |
length units |
meter, micrometer, millimeter, centimeter, decameter, hectometer, kilometer, micro-inch, milli-inch, inch, feet, miles |
parameters |
by mathematical expressions |
building actions |
- new primitives of many kinds, poly-primitives, 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.
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recipe |
- all actions are listed in a geometric recipe text
- can be easily edited and re-evaluated (directly in the GUI or in the geometry file)
- ‘slow evaluation’ available for step-wise inspection of the building process
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easy handling |
- undo & redo
- select primitives by picking
- tools to search & locate primitives, get exact distance between 2 points, hide part of the geometry
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positioning of domains, materials and boundaries |
- geometry & meshing is physics-free
- 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
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meshing |
element size |
- steerable by 1 number for ‘default’ line meshing setting
- can be overruled for each line by mathematical expression
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lines |
uniform element size, or grading in 1 of 2 directions, or bump grading |
surfaces |
- triangular
- quad-dominated
- sweep meshing, for 3- or 4-sided surfaces
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bodies |
- tet-meshing
- quad-dominated
- sweep meshing, for bodies with shapes that enable this, like any body made by a sweep geometry action
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non-matchings |
- on planar parts of the geometry, non-matching connections between 2 surfaces or 2 bodies are allowed
- without noticeable degradation of the solver
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Gmsh meshes |
import of Gmsh meshes is possible
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files |
- geometry & meshing (a)
- mesh (a or b)
- case (a)
- results (a or b)
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- 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 plain-text editor and re-loaded
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physics: thickness and cross-section fields |
- axi-symmetry
- spherical-symmetry
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- 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 axi-symmetric calculations
- not yet available for linear elasticity
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physics: models |
flow |
- Navier-Stokes, 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 full-density approach
- user-defined forces by mathematical expressions
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turbulence models (RANS) |
- Spalart-Allmaras model
- Shear Stress Transport model
- with or without wall functions
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heat |
temperature equation |
radiation |
- Discrete Ordinates model
- several Sn ordinate sets (modified Balsara Sn2 to Sn12)
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solutes |
- any number of user-defined solutes
- useable as tracer, pollutant species etc.
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electro-magnetism |
- electro-statics
- DC current
- Joulean heat release if DC combined with heat model
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linear elasticity |
- displacement-pressure 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
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anisotropy |
- permeability for Darcy flow
- heat conductivity
- solute diffusivities
- electric conductivity and electric permittivity
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physics: user variables |
- single-valued
- scalar fields
- vector fields
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- can be set by mathematical expressions, may depend on location, any solution field, time, other user variables etc.
- single-valued 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 non-SI units
- etc. etc.
- when defined before the calculation: updated each iteration
- when defined after the calculation: can directly be evaluated using the current results
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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 multi-physics
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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
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physics: numerics |
space discretisation |
- colocated cell-centered finite volume method
- optional TVD for convective fluxes
- fully conservative, when converged balances add up to 0 (also on coarse meshes)
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time discretisation |
- 1-or 2-step Backward Difference Formula for flow, heat etc.
- for linear elasticity: Bossak-alpha method
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model iterations |
- each big iteration constitutes a loop over all models that are activated (‘segregated approach’)
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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 ‘not-too-bad’ meshes
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linear solvers |
- PARDISO direct solver
- iterative solvers from the Paralution library
- state-of-the-art iterative solvers
- default settings are good, but combination preconditioner & solver is chooseable
- optionally with use of CUDA GPU computing (for larger NVIDIA graphical cards)
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parallel |
- both matrix assembly and solve steps parallelised for use on multi-core CPU’s
- number of used cores/threads chooseable
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result analysis |
XY plots |
- convergence plot shows the residuals
- user defined graphs for field values on straight lines
- single-valued user variables versus iteration number, or versus time
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3D graphics |
- contours: element wise or smoothed, iso-lines, banded or iso-surfaces
- vectors
- tensors (e.g. stress- or strain tensor)
- stream-lines
- 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
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