Prediction of ducted diaphragm noise using a stochastic approach with adapted temporal filters

Karban U., Schram C., Sovardi C., Polifke W.

INTERNATIONAL JOURNAL OF AEROACOUSTICS, cilt.18, sa.1, ss.49-72, 2019 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 18 Sayı: 1
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1177/1475472x18812811
  • Dergi Adı: INTERNATIONAL JOURNAL OF AEROACOUSTICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.49-72
  • Anahtar Kelimeler: Stochastic noise generation and radiation method, aeroacoustic analogies, duct acoustics, tailored Green's function, large eddy simulation, BOUNDARY-CONDITIONS, TURBULENT VELOCITY, SIMULATION, FLOW, WAVE
  • Orta Doğu Teknik Üniversitesi Adresli: Hayır

Özet

The noise production by ducted single- and double-diaphragm configurations is simulated using a stochastic noise generation and radiation numerical method. The importance of modeling correctly the anisotropy and temporal de-correlation is discussed, based on numerical results obtained by large eddy simulation. A new temporal filter is proposed, designed to provide the targeted spectral decay of energy in an Eulerian reference frame. An anisotropy correction is implemented using a non-linear model. The acoustic propagation problem is solved using Lighthill's aeroacoustic analogy with a tailored Green's function obtained analytically. Comparison with scale-resolved data indicates that accurate far-field noise predictions are obtained for both single and double diaphragm configurations, with computational costs significantly reduced with respect to the scale-resolved approach. A grouping scheme for the noise sources based on the octree structure is introduced to minimize the memory requirements and further reduce the computational cost.