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海网Ffowcs Williams-Hawkings Soundpropagation宅嗨网随网海网宅嗨网宅海网CD-adapcoadapco training course entitled "Aeroacoustics"and should not be altered,edited or1distributed without the consent of the author.Ffowcs Williams-Hawkings sound propagation modelSound propagation can be solved with CFD using wherever possible the 2nd ordersolver in STAR-CCM+.Requirement:20 cells per propagated wavelength.Typically affordable only for near field acoustic analysis.Ffowcs Williams-Hawkings tries to reduce this burden.For compact noise sources.Noise sources are enclosed by a surface completely separated from the microphone locations.Often applies to external flows.-For internal flow sound reflections require to enlarge the enclosing surface>FW-H modeladvantage is reduced.A surface integral is evaluated per microphone location at each time step.宅嗨网宅嗨网网海Copyright 2012 CD-adapco.The following material constitutes a portion of the CD-CD-adapcoadapco training course entitled "Aeroacoustics"and should not be altered,edited ordistributed without the consent of the author.2Ffowcs Williams-Hawkings Setup EntitiesNoise is propagated from surfaces.Impermeable surfaces.-Typically walls,every source and reflectingsurface should be included.SideMirror3DCADGeometryDipole density is evaluated from time sampleof the flow.ContinuaRegions·Permeable surfaces.Derived PartsMass permeable surface,interfaces in STAR-FW-H SurfacesCCM+.Impermeable Surface 1Currently zero mean flow requiredFW-H Receivers-Quadrupole density is evaluated.M1-FHWM4-FHWNoise is propagated to receivers.M10-FHWPoint receivers,defined at microphoneM11-FHWlocation to collect the data.M14-FHWSolversCopyright 2012 CD-adapco.The following material constitutes a portion of the CD-CD-adapcoadapco training course entitled "Aeroacoustics"and should not be altered,edited ordistributed without the consent of the author.3Activation of FW-H ModelPhysics Model Selection鈽扴elect physics for unsteadyFfom:Williarns-Hewking>RANS,DES or LES simulation.Select option Aeroacoustics.1D CouplingThermal Co TfortTurbulertChoose the FW-H model as shown.The simulation tree then shows theRadiationGamTa ReTnetanew FW-H nodes.Choose the surface type for the newsource surface and then select allwall boundary or in-place interfacesContinuacontributing to the source.□RegionsDomainSimilarly receivers can be created.□Derived Parts□FW-H Surfac4NewImpermeable SurfaceImpermea□FW-HReceivePermeable Surface宅嗨网●M1-FHWPasteCtrl-VM4-FHWRefreshM10-FHWM11-FHWM14-FHWCopyright 2012 CD-adapco.The following material constitutes a portion of the CD-CD-adapcoadapco training course entitled "Aeroacoustics"and should not be altered,edited ordistributed without the consent of the author.