TY - JOUR
T1 - Integration methods for distributed sound sources
AU - Merino-Martínez, Roberto
AU - Sijtsma, Pieter
AU - Carpio, Alejandro Rubio
AU - Zamponi, Riccardo
AU - Luesutthiviboon, Salil
AU - Malgoezar, Anwar M.N.
AU - Snellen, Mirjam
AU - Schram, Christophe
AU - Simons, Dick G.
PY - 2019
Y1 - 2019
N2 - Most acoustic imaging methods assume the presence of point sound sources and, hence, may fail to correctly estimate the sound emissions of distributed sound sources, such as trailing-edge noise. In this contribution, three integration techniques are suggested to overcome this issue based on models considering a single point source, a line source, and several line sources, respectively. Two simulated benchmark cases featuring distributed sound sources are employed to compare the performance of these integration techniques with respect to other well-known acoustic imaging methods. The considered integration methods provide the best performance in retrieving the source levels and require short computation times. In addition, the negative effects of the presence of unwanted noise sources, such as corner sources in wind-tunnel measurements, can be eliminated. A sensitivity analysis shows that the integration technique based on a line source is robust with respect to the choice of the integration area (shape, position, and mesh fineness). This technique is applied to a trailing-edge-noise experiment in an open-jet wind tunnel featuring a NACA 0018 airfoil. The location and far-field noise emissions of the trailing-edge line source were calculated.
AB - Most acoustic imaging methods assume the presence of point sound sources and, hence, may fail to correctly estimate the sound emissions of distributed sound sources, such as trailing-edge noise. In this contribution, three integration techniques are suggested to overcome this issue based on models considering a single point source, a line source, and several line sources, respectively. Two simulated benchmark cases featuring distributed sound sources are employed to compare the performance of these integration techniques with respect to other well-known acoustic imaging methods. The considered integration methods provide the best performance in retrieving the source levels and require short computation times. In addition, the negative effects of the presence of unwanted noise sources, such as corner sources in wind-tunnel measurements, can be eliminated. A sensitivity analysis shows that the integration technique based on a line source is robust with respect to the choice of the integration area (shape, position, and mesh fineness). This technique is applied to a trailing-edge-noise experiment in an open-jet wind tunnel featuring a NACA 0018 airfoil. The location and far-field noise emissions of the trailing-edge line source were calculated.
KW - Acoustic imaging
KW - integration methods
KW - porous trailing edge
KW - trailing-edge noise
UR - http://www.scopus.com/inward/record.url?scp=85067861589&partnerID=8YFLogxK
U2 - 10.1177/1475472X19852945
DO - 10.1177/1475472X19852945
M3 - Article
AN - SCOPUS:85067861589
SN - 1475-472X
VL - 18
SP - 444
EP - 469
JO - International Journal of Aeroacoustics
JF - International Journal of Aeroacoustics
IS - 4-5
ER -