Parallel solver for unsteady, turbulent incompressible flows enhanced with heat and mass transfer/buoyancy effects.

Numerical method characteristics

  • Flow and heat transfer equations are solved strongly coupled.
  • It is based on the pseudocompressibility concept for the solution of steady/unsteady, 2D/3D, turbulent flows
  • It uses hybrid unstructured meshes.
  • Dual time stepping: Second order  three point backward scheme in physical time, first order backward Euler implicit scheme in pseudotime. Local time stepping in pseudotime for convergence acceleration.
  • Upwind scheme for inviscid fluxes (second or third order accurate for mean flow and first order accurate for turbulence model)
  • Central scheme for viscous fluxes (second order accurate)

Numerical surface mesh in FiDES modeler
Numerical surface mesh
Visibility evolution
Visibility evolution


      Synchronized fire-crowd simulations (in cooperation with SIMPLAN AG, Hanau)

Turbulence Models

  • Standard k-ε turbulence model
  • k-ω SST
  • k-ω ΤΝΤ
  • k-ε MMK
  • Large Eddy Simulation (LES)


  • Parallel CFD code based on the MPI protocol (MPICH2 and OpenMPI 64 bit implementations). The Single Program Multiple Data (SPMD) approach has been adopted. Mesh partitioning in subdomains is required to assign each processor/node a subdomain.
  • Applied on hybrid unstructured meshes.
  • Radiation model based on Finite Volume Method.
  • Contaminant concentration field (soot, combustion products).  
  • Fire suppression by sprinklers (Lagrangian treatment and droplets’ tracing).
  • Simulation of HVAC systems.
  • 1D simplified heat conduction through walls coupled with the CFD simulation.

Simulation of fire events in tunnels
Simulation of fire events in tunnels - Backlayering effect
CFD simulation for indoor microclimate
Mixing cooling in an amphitheater
CFD simulation for indoor microclimate
Thermal comfort and HVAC performance

New Capabilities

  • Model generation from IFC (IFC4) files. Recognition of spaces, simplification of geometry and imposition of boundary conditions.
  • Advanced Finite Volume model for heat radiation
  • Heat Release Rate Properties of different materials
  • Implementation of dynamic geometrical elements
  • Incorporation of HVAC and BACS
  • Modelling of active and passive fire protection systems
  • Modeling of toxic gas dispersion considering additional buoyancy effects
  • Coupling with crowd simulation application for evaluating evacuation strategies via a TCP/IP communication model
  • Participation of smoke in the modeling of thermal radiation
  • Material library with suitable properties
  • Fire spread on the lining and the furniture.
  • Evaluation of the results according to human safety criteria. Definition of suitable metrics/KPIs

CFD simulation for outdoor wind field analysis
Numerical surface mesh
CFD simulation for outdoor wind field analysis
Streamlines, pressure distribution on buildings’ surfaces
CFD simulation for outdoor wind field analysis
Wind velocity around the building of interest

Datasheet Download

Please read more about the program

About Page