Technical Details and main features.

VNoise main page
Additional Modules
FWH Solver: Aeroacoustic of blades and fans.
Flow-Noise: Flow generated noise.
VNoiseCluster: Parallel calculations.
Computational core 
  • Frequency response with FEM
  • Frequency response with direct and indirect BEM.
  • Coupled FEM-BEM analyses.
  • Acoustic cavity modes.
  • Coupled structural-acoustic cavity modes. 
  • Fully coupled structural-acoustic analysis through the coupling with modal structural equations.  
  • Internal, external and mixed problems.
  • Contribution Vectors for fast multi frequency radiation analysis (i.e. engine run up).
  • Extremely complete set of boundary conditions, including pressure, velocity, and robin conditions, as well as free edges, radiation conditions, and baffled and un-baffled aperture, for openings simulation.
  • Sound absorbing trims with acoustic impedance.
  • Complex speed of sound and densities, for modelling bulk reacting materials.
  • Different speed of sound and densities for different domains in the same calculation.
  • User customizable coupling conditions at interfaces between different domains.
  • Impedance and transfer matrix relations for black box modelling of filters and other acoustics elements.
  • Modelling of perforated tubes and surfaces.
  • Frequency interpolation for multi frequency analysis.
  • Half space formulation, planar, and axial symmetries.
  • Fully automatic, and extremely robust routine for CHIEF nodes.
  • Isoparametric discretization of 1st and 2nd order.
  • Monopole and dipole sound sources with user customizable frequency dependent intensity.
  • User customizable sound source by direct import of pressure.
  • Linear system solved using an iterative solver of the GMRES family that ensure great convergence speeds and stability.
  • Direct Solver for small sized problems.
  • Automatic use of out of core solver for big problems.
  • Multiple load case analysis.
  • Random Vibroacoustic analysis with evaluation of principal components response matrix (multiple load case analysis) from principal components PSD of excitation.
  • Modeling of perforated surfaces.
  • Fast Multi Domain for BEM internal analysis with increased speed and reduced memory requirements.

FWH Solver

  • Sound radiated by aeroacoustic sources such as rotating blades, fans, and turbulence.
  • Use unsteady pressure computed by CFD codes for the evaluation of radiated sound using an acoustic analogy based on the integration of the full FWH equations.
  • Interface with CFD codes (Fluent).

User Interface

  • PC Based (Windows XP/2000/NT).
  • CAD and meshing features for modelling simple geometries.
  • Full Interface with FEM/CAE tools including NASTRAN (bulk, f06, MSC op2, punch), ANSYS (rst), FEMAP, NEiNastran, Patran Neutral Files.
  • Automatic features for converting FEM meshes into BEM meshes (Free edge and intersection detection, nodes disconnection, normal orientation check, hole closure, Volume elements skin detection, check for degenerated elements).
  • Batch file for automating multiple operations and analysis.
  • Easily programmable TAG based ASCII file format (VNoiseX) for automating import/export operations.
  • Advanced import features for managing large FEM results files.
  • Fully Automatic Mesh Coarsening based on an edge collapsing technique tailored for acoustic.
  • Modal and velocity data projection with stable and accurate 3D interpolation and integration routines that permit to easily exchange data among different sources and discretizations.
  • Simultaneous use of different models and analysis in background. The user can execute a calculation while he is executing pre-post processing operations with other models.
  • Complete set of 2D and 3D plots and animations.
  • Evaluation of Intensity, SPL, RMS, dBA, dBC, 1/3 octave, and specific functions for Transmission Loss and Insertion Loss.
  • Transmission Loss of multi input - multi output systems.
  • Sound Power evaluation from direct Intensity integration or from ISO procedures.
  • Audio Replay capabilities for listening to the computed noise (wave files generation for further processing outside VNoise).
  • Microphones arrays (Spherical, annular, planar).
  • Structural forces and pressure distributions.
  • Complete documentation and tutorials.
  • On line technical support.

FEMAP/NeiNastran Interface

  • Direct link that permits to exchange model and data with FEMAP/NeiNastran.
  • Through FEMAP provide VNoise interface to the CAD tools supported by FEMAP (CATIA, Pro/Engineer, AutoDesk, SolidWorks and Solid Edge).

VNoise Cluster

  • Distribute huge calculations across a simple PC network. No configuration needed.
  • Impressive increase of computational power at a low software and hardware cost.