TY - CHAP A1 - Herold, Gert A1 - Sarradj, Ennes T1 - Preliminary Benchmarking of Microphone Array Methods T2 - Proceedings, Berlin Beamforming Conference, 2014 Y1 - 2014 SN - 978-3-942709-12-5 SN - 3-942709-12-0 PB - Gesellschaft zur Förderung angewandter Informatik ER - TY - CHAP A1 - Herold, Gert A1 - Sarradj, Ennes T1 - Vergleich von Mikrofonarrayverfahren zur Schallquellencharakterisierung T2 - DAGA 2014, 40. Jahrestagung für Akustik, "Fortschritte der Akustik" 10. - 13. März 2014 Oldenburg Y1 - 2014 SN - 978-3-939296-06-5 SP - 624 EP - 625 PB - Deutsche Gesellschaft für Akustik CY - Berlin ER - TY - CHAP A1 - Sarradj, Ennes A1 - Geyer, Thomas A1 - Herold, Gert T1 - Dreidimensionale Quellcharakterisierung mit fortschrittlichen Mikrofonarrayverfahren für die Anwendung in der Maschinenakustik T2 - Maschinenakustik 2014, Wettbewerbsvorteil durch geräuscharme Produkte sichern, Karlsruhe, 12.-13.11.2014 Y1 - 2014 SN - 978-3-18-092229-4 SP - 171 EP - 184 PB - VDI-Verlag CY - Düsseldorf ER - TY - CHAP A1 - Herold, Gert A1 - Sarradj, Ennes A1 - Geyer, Thomas T1 - Covariance Matrix Fitting for Aeroacoustic Application T2 - Fortschritte der Akustik - AIA-DAGA 2013 Y1 - 2013 SP - 1926 EP - 1928 PB - Deutsche Gesellschaft für Akustik ER - TY - GEN A1 - Geyer, Thomas A1 - Sarradj, Ennes A1 - Herold, Gert T1 - Flow Noise Generation of Cylinders with Soft Porous Cover T2 - 21st AIAA/CEAS Aeroacoustics Conference 2015, Dallas, Texas, USA, 22 - 26 June 2015, held at the AIAA Aviation Forum 2015, vol. 5, (AIAA 2015-3147) Y1 - 2015 SN - 978-1-5108-0820-1 SP - 3695 EP - 3711 PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Herold, Gert A1 - Sarradj, Ennes T1 - Microphone Array Method for the Characterization of Rotating Sound Sources in Axial Fans T2 - Fan 2015, International Conference on Fan Noise, Technology and Numerical Methods, Lyon 2015 Y1 - 2015 SN - 978-0-9572374-3-8 PB - Institution of Mechanical Engineers CY - London ER - TY - GEN A1 - Herold, Gert A1 - Sarradj, Ennes T1 - An Approach to Estimate the Reliability of Microphone Array Methods T2 - 21st AIAA/CEAS Aeroacoustics Conference 2015, Dallas, Texas, USA, 22 - 26 June 2015, held at the AIAA Aviation Forum 2015, vol. 4, (AIAA 2015-2977) Y1 - 2015 SN - 978-1-5108-0820-1 SP - 2688 EP - 2697 PB - Curran CY - Red Hook, NY ER - TY - CHAP A1 - Herold, Gert A1 - Sarradj, Ennes T1 - Mikrofonarrayverfahren zur Messung der abgestrahlten Schallleistung von Motorkomponenten T2 - Fortschritte der Akustik, DAGA 2015, Nürnberg, 41. Jahrestagung für Akustik, 16. - 19. März 2015 Y1 - 2015 SN - 978-3-939296-08-9 PB - Deutsche Gesellschaft für Akustik e.V. CY - Berlin ER - TY - GEN A1 - Herold, Gert A1 - Zenger, Florian A1 - Sarradj, Ennes T1 - Analyzing Noise Components on Skewed Fans with a Virtual Rotating Microphone Array : AIAA paper 2016-2761 T2 - 22nd AIAA/CEAS Aeroacoustics Conference 2016, Lyon, France, 30 May-1 June 2016 Y1 - 2016 SN - 978-1-5108-2672-4 PB - Curran Associates CY - Red Hook, NY ER - TY - CHAP A1 - Herold, Gert A1 - Sarradj, Ennes T1 - Frequency Domain Deconvolution for Rotating Sources on an Axial Fan T2 - BeBeC, 6th Berlin Beamforming Conference, February 29 - March 1, 2016, proceedings Y1 - 2016 PB - Berlin CY - Gesellschaft zur Förderung angewandter Informatik ER - TY - GEN A1 - Caldas, Luciano A1 - Greco, Paolo A1 - Herold, Gert A1 - Baccalá, Luiz T1 - In-Duct Rotating Beamforming and Mode Detection of Fan Noise Sources : AIAA paper 2016-3034 T2 - 22nd AIAA/CEAS Aeroacoustics Conference 2016, Lyon, France, 30 May-1 June 2016, vol. 7 Y1 - 2016 SN - 978-1-5108-2672-4 SP - 5140 EP - 5155 PB - Curran Associates CY - Red Hook, NY ER - TY - GEN A1 - Zenger, Florian A1 - Herold, Gert A1 - Becker, Stefan A1 - Sarradj, Ennes T1 - Sound source localization on an axial fan at different operating points T2 - Experiments in Fluids Y1 - 2016 U6 - https://doi.org/10.1007/s00348-016-2223-8 SN - 0723-4864 SN - 1432-1114 VL - 57 SP - 136 ER - TY - GEN A1 - Zenger, Florian A1 - Herold, Gert A1 - Becker, Stefan T1 - Acoustic Characterization of Forward- and Backward-Skewed Axial Fans under Increased Inflow Turbulence : AIAA paper 2016-2943 T2 - 22nd AIAA/CEAS Aeroacoustics Conference 2016, Lyon, France, 30 May-1 June 2016, vol. 4 Y1 - 2016 SN - 978-1-5108-2672-4 SP - 3682 EP - 3694 PB - Curran Associates CY - Red Hook, NY ER - TY - CHAP A1 - Herold, Gert A1 - Sarradj, Ennes T1 - Acoular - Open-Source-Software zur Anwendung von Mikrofonarrayverfahren T2 - Fortschritte der Akustik, DAGA 2016, Aachen, 14.-17. März 2016, 42. Jahrestagung für Akustik Y1 - 2016 SN - 978-3-939296-10-2 PB - DAGA CY - Berlin ER - TY - GEN A1 - Sarradj, Ennes A1 - Herold, Gert T1 - A Python framework for microphone array data processing T2 - Applied Acoustics Y1 - 2016 U6 - https://doi.org/10.1016/j.apacoust.2016.09.015 SN - 0003-682X VL - 116 SP - 50 EP - 58 ER - TY - GEN A1 - Herold, Gert A1 - Geyer, Thomas A1 - Markus, Philipp A1 - Sarradj, Ennes T1 - Simultaneous Sound Power Measurement of Engine Components T2 - SAE International Journal of Passenger Cars - Mechanical Systems Y1 - 2016 U6 - https://doi.org/10.4271/2016-01-1774 SN - 1946-3995 SN - 1946-4002 VL - 9 IS - 3 SP - 974 EP - 979 ER - TY - CHAP A1 - Hall, Philipp A1 - Herold, Gert A1 - Geyer, Thomas A1 - Sarradj, Ennes T1 - Vergleich verschiedener Methoden zur Schallleistungsbestimmung von Maschinenkomponenten T2 - Fortschritte der Akustik, 43. Deutsche Jahrestagung für Akus tik, 6.-9. März 2017 in Kiel Y1 - 2017 UR - https://www.dega-akustik.de/fileadmin/dega-akustik.de/publikationen/DAGA/DAGA_17_Inhalt.pdf SN - 978-3-939296-12-6 SP - 564 EP - 567 PB - Deutsche Gesellschaft für Akustik e.V. (DEGA) CY - Berlin ER - TY - GEN A1 - Sarradj, Ennes A1 - Herold, Gert A1 - Sijtsma, Pieter A1 - Merino-Martinez, Roberto A1 - Geyer, Thomas A1 - Bahr, Christopher A1 - Porteous, Ric A1 - Moreau, Danielle J. A1 - Doolan, Con T1 - A Microphone Array Method Benchmarking Exercise using Synthesized Input Data T2 - 23rd AIAA/CEAS Aeroacoustics Conference 2017, Denver, USA, 5 June - 9 June 2017, (AIAA 2017-3719) Y1 - 2017 UR - https://arc.aiaa.org/doi/pdfplus/10.2514/6.2017-3719 SN - 978-1-62410-504-3 PB - AIAA CY - Reston, Va ER - TY - GEN A1 - Herold, Gert A1 - Geyer, Thomas A1 - Sarradj, Ennes T1 - Comparison of Inverse Deconvolution Algorithms for High-resolution Aeroacoustic Source Characterization T2 - 23rd AIAA/CEAS Aeroacoustics Conference 2017, Denver, USA, 5 June - 9 June 2017, (AIAA 2017-4177) Y1 - 2017 UR - https://arc.aiaa.org/doi/abs/10.2514/6.2017-4177 SN - 978-1-62410-504-3 PB - AIAA CY - Reston, Va ER - TY - GEN A1 - Hoeltgen, Laurent A1 - Breuß, Michael A1 - Herold, Gert A1 - Sarradj, Ennes T1 - Sparse ℓ1 regularisation of matrix valued models for acoustic source characterisation T2 - Optimization and Engineering N2 - We present a strategy for the recovery of a sparse solution of a common problem in acoustic engineering, which is the reconstruction of sound source levels and locations applying microphone array measurements. The considered task bears similarities to the basis pursuit formalism but also relies on additional model assumptions that are challenging from a mathematical point of view. Our approach reformulates the original task as a convex optimisation model. The sought solution shall be a matrix with a certain desired structure. We enforce this structure through additional constraints. By combining popular splitting algorithms and matrix differential theory in a novel framework we obtain a numerically efficient strategy. Besides a thorough theoretical consideration we also provide an experimental setup that certifies the usability of our strategy. Finally, we also address practical issues, such as the handling of inaccuracies in the measurement and corruption of the given data. We provide a post processing step that is capable of yielding an almost perfect solution in such circumstances. KW - Convex optimisation KW - Sparse recovery KW - Split Bregman KW - Microphone array KW - Matrix differentiation KW - Acoustic source characterisation Y1 - 2018 U6 - https://doi.org/10.1007/s11081-017-9357-2 SN - 1389-4420 SN - 1573-2924 VL - 19 IS - 1 SP - 39 EP - 70 ER - TY - CHAP A1 - Jekosch, Simon A1 - Sarradj, Ennes A1 - Herold, Gert A1 - Geyer, Thomas T1 - Comparison of different solvers for general inverse beamforming algorithms for highresolution aeroacoustic source characterization T2 - 7th Berlin Beamforming Conference, BeBeC Y1 - 2018 UR - http://www.bebec.eu/Downloads/BeBeC2018/Papers/BeBeC-2018-D08.pdf ER - TY - CHAP A1 - Sarradj, Ennes A1 - Herold, Gert A1 - Geyer, Thomas T1 - Vergleich verschiedener Mikrofonarray-Verfahren anhand synthetischer Daten T2 - Fortschritte der Akustik - DAGA 2018, 44. Jahrestagung für Akustik, 19.-22. März 2018 in München Y1 - 2018 UR - https://www-docs.b-tu.de/fg-akustik/public/veroeffentlichungen/sarradj_mikrofonarrayverfahren_daga2018.pdf SP - 1391 EP - 1394 PB - Deutsche Gesellschaft für Akustik CY - Berlin ER - TY - GEN A1 - Merino-Martinez, Roberto A1 - Sijtsma, Pieter A1 - Snellen, Mirjam A1 - Ahlefeldt, Thomas A1 - Antoni, Jerome A1 - Bahr, Christopher A1 - Blacodon, Daniel A1 - Ernst, Daniel A1 - Finez, Arthur A1 - Funke, Stefan A1 - Geyer, Thomas A1 - Haxter, Stefan A1 - Herold, Gert A1 - Huang, Xun A1 - Humphreys, William A1 - Leclère, Quentin A1 - Malgoezar, Anwar A1 - Michel, Ulf A1 - Padois, Thomas A1 - Pereira, Antonio A1 - Picard, Christophe A1 - Sarradj, Ennes A1 - Siller, Henri A1 - Simons, Dick A1 - Spehr, Carsten T1 - A review of acoustic imaging methods using phased microphone arrays T2 - CEAS Aeronautical Journal N2 - Phased microphone arrays have become a well-established tool for performing aeroacoustic measurements in wind tunnels (both open-jet and closed-section), flying aircraft, and engine test beds. This paper provides a review of the most well-known and state-of-the-art acoustic imaging methods and recommendations on when to use them. Several exemplary results showing the performance of most methods in aeroacoustic applications are included. This manuscript provides a general introduction to aeroacoustic measurements for non-experienced microphone-array users as well as a broad overview for general aeroacoustic experts. Y1 - 2019 U6 - https://doi.org/10.1007/s13272-019-00383-4 SN - 1869-5582 SN - 1869-5590 VL - 10 IS - 1 SP - 197 EP - 230 ER - TY - GEN A1 - Geyer, Thomas A1 - Schneehagen, Erik W. A1 - Herold, Gert A1 - Zhang, Tingyi A1 - Moreau, Danielle J. T1 - Reduction of rotor aerodynamic noise using porous blade tips T2 - Fortschritte der Akustik - DAGA, 50. Jahrestagung für Akustik N2 - Motivated by promising results from experiments on the noise reduction performance of finite wall-mounted airfoils with a porous tip in an aeroacoustic wind tunnel, corresponding measurements were performed in a dedicated rotor test rig. This rig features a 3 kW direct-drive electric motor with three rotor blades of 1.1 m diameter. In the experiments, a variety of different tip modifications was tested regarding their noise reducing performance, including different porous materials that were manufactured using rapid prototyping. Acoustic measurements were performed at different rotationals speeds and blade angles using a ring-shaped microphone array consisting of 60 evenly spaced microphones. The rotational speed was measured using a laser sensor. Different beamforming algorithms were used in post-processing to help analyzing the data. The results show that porous tips can lead to a notable noise reduction at low frequencies, but a small penalty at medium and high frequencies which may be due to the surface roughness of the porous tips. This trend seems more severe for lower blade angles than for higher ones. These findings agree well with those obtained from the previous wind tunnel measurements. Y1 - 2024 UR - https://pub.dega-akustik.de/DAGA_2024/konferenz?article=471 ER -