Predicting far-field broadband noise levels from in-duct phased array measurements

Tester B. J., ÖZYÖRÜK Y.

20th AIAA/CEAS Aeroacoustics Conference 2014, Atlanta, GA, Amerika Birleşik Devletleri, 16 - 20 Haziran 2014 identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Cilt numarası:
  • Doi Numarası: 10.2514/6.2014-2913
  • Basıldığı Şehir: Atlanta, GA
  • Basıldığı Ülke: Amerika Birleşik Devletleri
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Far-field inlet fan noise can be measured in the AneCom test facility under anechoic conditions but far-field aft fan measurements are not possible because the bypass flow is ducted away through a throttle valve into an exhaust stack. A beamformer-based technique has been developed for processing measurements taken with an in-duct axial ('phased') array, which with certain modelling assumptions, enables the fan broadband noise level and directivity to be predicted in the far-field. The status of this 'in-duct to far-field' method is reviewed, in terms of validation with experimental data and its further development to include realistic bypass nozzle geometry and duct/nozzle flow Mach numbers.