@misc{MoreauGeyerDoolanetal., author = {Moreau, Danielle J. and Geyer, Thomas and Doolan, Con and Sarradj, Ennes}, title = {Surface curvature effects on the tonal noise of a wall-mounted finite airfoil}, series = {The Journal of the Acoustical Society of America}, volume = {143}, journal = {The Journal of the Acoustical Society of America}, number = {6}, issn = {1520-8524}, doi = {10.1121/1.5040981}, pages = {3460 -- 3473}, abstract = {This paper is concerned with the influence of camber on the noise of a wall-mounted finite airfoil with natural boundary layer transition. Tonal noise measurements taken in an aeroacoustic wind tunnel are presented for airfoils with aspect ratio of 2, NACAxx12 profile and camber between 0 and 6\% at 40\% chord. The results show camber is an important parameter that determines the operating conditions for which acoustic tone generation occurs and the number and intensity of the tones produced. Airfoils with 0\%-2\% camber have an acoustic signature that is dominated by a high amplitude primary tone, whereas the spectra of airfoils with higher camber of 4\%-6\% feature a more pronounced side tone structure. Tonal noise production does not collapse with lift coefficient, demonstrating that the local flow conditions influence the noise source. Tonal noise production is explained in terms of changes to mean flow topology, namely the location of flow separation, which is linked to tonal noise generation. Scaling of airfoil tonal noise is found to vary with angle of attack and pressure gradient. Empirical scaling laws for the primary tone frequency dependence on velocity are also derived for the cambered airfoils.}, language = {en} } @misc{GeyerMoreauGiesleretal., author = {Geyer, Thomas and Moreau, Danielle J. and Giesler, Jens and Hall, Philipp and Sarradj, Ennes and Doolan, Con}, title = {Measurement of the noise generated by wall-mounted airfoils of different thickness}, series = {24th AIAA/CEAS Aeroacoustics Conference 2018, Atlanta, USA, 25 June - 29 June 2018, (AIAA 2018-3796)}, journal = {24th AIAA/CEAS Aeroacoustics Conference 2018, Atlanta, USA, 25 June - 29 June 2018, (AIAA 2018-3796)}, publisher = {AIAA}, address = {Reston, Va}, isbn = {978-1-62410-560-9}, language = {en} } @misc{GeyerSharmaSarradj, author = {Geyer, Thomas and Sharma, Sparsh and Sarradj, Ennes}, title = {Detached Eddy Simulation of the Flow Noise Generation of Cylinders with Porous Cover}, series = {24th AIAA/CEAS Aeroacoustics Conference 2018, Atlanta, USA, 25 June - 29 June 2018, (AIAA 2018-3472)}, journal = {24th AIAA/CEAS Aeroacoustics Conference 2018, Atlanta, USA, 25 June - 29 June 2018, (AIAA 2018-3472)}, publisher = {AIAA}, address = {Reston, Va}, isbn = {978-1-62410-560-9}, language = {en} } @misc{CaldichourySouliSarradjetal., author = {{\c{C}}aldichoury, I{\~n}aki and Souli, Mhamed and Sarradj, Ennes and Geyer, Thomas and Del Pin, Facundo}, title = {Numerical investigation of flow around hairy flaps cylinder using FSI Capabilities}, series = {The International journal of multiphysics}, volume = {12}, journal = {The International journal of multiphysics}, number = {2}, issn = {2048-3961}, pages = {189 -- 208}, language = {en} } @inproceedings{SharmaSarradj, author = {Sharma, Sparsh and Sarradj, Ennes}, title = {Fluctuating inflow conditions for time-domain boundary element method for airfoil-turbulence interaction noise}, series = {Proceedings of the 15th International Symposium on Unsteady Aerodynamics, Aeroacoustics \& Aeroelasticity of Turbomachines ISUAAAT15, 24-27 September 2018, University of Oxford, UK}, booktitle = {Proceedings of the 15th International Symposium on Unsteady Aerodynamics, Aeroacoustics \& Aeroelasticity of Turbomachines ISUAAAT15, 24-27 September 2018, University of Oxford, UK}, publisher = {ISUAAAT Scientific Committee}, pages = {8}, language = {en} } @inproceedings{GeyerSarradj, author = {Geyer, Thomas and Sarradj, Ennes}, title = {Noise reduction and aerodynamics of airfoils with porous trailing edges}, series = {INTER-NOISE 2018, the 47th International Congress and Exposition on Noise Control Engineering, Chicago, Illinois, USA}, booktitle = {INTER-NOISE 2018, the 47th International Congress and Exposition on Noise Control Engineering, Chicago, Illinois, USA}, pages = {10}, language = {en} } @inproceedings{SharmaGeyerSarradj, author = {Sharma, Sparsh and Geyer, Thomas and Sarradj, Ennes}, title = {Time Domain Boundary Element Method for the Leading-Edge Noise subjected to Linear Vorticity}, series = {INTER-NOISE 2018, the 47th International Congress and Exposition on Noise Control Engineering, Chicago, Illinois, USA}, booktitle = {INTER-NOISE 2018, the 47th International Congress and Exposition on Noise Control Engineering, Chicago, Illinois, USA}, pages = {10}, language = {en} } @misc{GeyerLuciusSchroedteretal., author = {Geyer, Thomas and Lucius, Andreas and Schr{\"o}dter, Marcus and Schneider, Marc and Sarradj, Ennes}, title = {Reduction of Turbulence Interaction Noise Through Airfoils With Perforated Leading Edges}, series = {Acta Acustica united with Acustica}, volume = {105}, journal = {Acta Acustica united with Acustica}, number = {1}, issn = {1610-1928}, doi = {10.3813/AAA.919292}, pages = {109 -- 122}, language = {en} } @misc{GeyerKampsSarradjetal., author = {Geyer, Thomas and Kamps, Laura and Sarradj, Ennes and Br{\"u}cker, Christoph}, title = {Vortex Shedding and Modal Behavior of a Circular Cylinder Equipped with Flexible Flaps}, series = {Acta Acustica united with Acustica}, volume = {105}, journal = {Acta Acustica united with Acustica}, number = {1}, issn = {1610-1928}, doi = {10.3813/aaa.919301}, pages = {210 -- 219}, language = {en} } @misc{SharmaSarradj, author = {Sharma, Sparsh and Sarradj, Ennes}, title = {Two-dimensional isotropic turbulent inflow conditions for vortex particle method}, series = {Physical Review Fluids}, volume = {4}, journal = {Physical Review Fluids}, number = {2}, issn = {2469-990X}, doi = {10.1103/PhysRevFluids.4.022701}, pages = {11}, language = {en} } @misc{HenkeNoackGeyeretal., author = {Henke, Anna-Sophia and Noack, Martin and Geyer, Thomas and Heinrich, Christoph Rocky and Beirow, Bernd and Sarradj, Ennes and K{\"u}hhorn, Arnold}, title = {Calculation of the Modal Behavior of Structured Sheet Metal}, series = {International Journal of Lightweight Materials and Manufacture}, journal = {International Journal of Lightweight Materials and Manufacture}, issn = {2588-8404}, doi = {10.1016/j.ijlmm.2019.01.004}, pages = {13}, language = {en} } @misc{HenkeTepeSarradj, author = {Henke, Anna-Sophia and Tepe, Ali and Sarradj, Ennes}, title = {Untersuchung des Abstrahlverhaltens strukturierter Bleche}, series = {Fortschritte der Akustik - DAGA 2019, 45. Jahrestagung f{\"u}r Akustik, 18.-21. M{\"a}rz 2019 in Rostock}, journal = {Fortschritte der Akustik - DAGA 2019, 45. Jahrestagung f{\"u}r Akustik, 18.-21. M{\"a}rz 2019 in Rostock}, abstract = {Stahlbleche sind auf Grund ihrer einfachen Fertigung und vielf{\"a}ltigen Anwendungsm{\"o}glichkeiten unentbehrlich in Bereichen wie dem Maschinen- und Fahrzeugbau oder der Architektur. Durch das Einbringen von Strukturen kann die Steifigkeit von Stahlplatten erh{\"o}ht werden. So kann bei einem geringeren Materialeinsatz gleichbleibenden statischen Anspr{\"u}chen gen{\"u}gt werden. Eine derartige Umformung f{\"u}hrt jedoch auch zu einem ver{\"a}nderten akustischen Verhalten von strukturierten Blechen gegen{\"u}ber glatten Blechen. Im Rahmen einer Studie an der BTU Cottbus-Senftenberg zum akustischen Verhalten hexagonal wabenstrukturierter Stahlbleche wurde das Abstrahlverhalten dieser Bleche untersucht. Dazu wurden im Fensterpr{\"u}fstand der TU Berlin experimentell die abgestrahlte Schallleistung sowie die Schwingschnelle von mit einem Shaker angeregten Blechen ermittelt. Aus den so gewonnenen Daten wurde das Abstrahlmaß berechnet. Der Beitrag zeigt das Verfahren und veranschaulicht die Ergebnisse vergleichend f{\"u}r glatte und hexagonal strukturierte Bleche. Dabei wird im Besonderen auf den Einfluss der Strukturierung auf das Abstrahlmaß der Stahlbleche eingegangen.}, language = {de} } @misc{MerinoMartinezSijtsmaSnellenetal., author = {Merino-Martinez, Roberto and Sijtsma, Pieter and Snellen, Mirjam and Ahlefeldt, Thomas and Antoni, Jerome and Bahr, Christopher and Blacodon, Daniel and Ernst, Daniel and Finez, Arthur and Funke, Stefan and Geyer, Thomas and Haxter, Stefan and Herold, Gert and Huang, Xun and Humphreys, William and Lecl{\`e}re, Quentin and Malgoezar, Anwar and Michel, Ulf and Padois, Thomas and Pereira, Antonio and Picard, Christophe and Sarradj, Ennes and Siller, Henri and Simons, Dick and Spehr, Carsten}, title = {A review of acoustic imaging methods using phased microphone arrays}, series = {CEAS Aeronautical Journal}, volume = {10}, journal = {CEAS Aeronautical Journal}, number = {1}, issn = {1869-5582}, doi = {10.1007/s13272-019-00383-4}, pages = {197 -- 230}, abstract = {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.}, language = {en} } @misc{GeyerSarradj, author = {Geyer, Thomas and Sarradj, Ennes}, title = {Self Noise Reduction and Aerodynamics of Airfoils With Porous Trailing Edges}, series = {Acoustics}, volume = {1}, journal = {Acoustics}, number = {2}, issn = {2624-599X}, doi = {10.3390/acoustics1020022}, pages = {393 -- 409}, language = {en} } @misc{SharmaGeyerSarradjetal., author = {Sharma, Sparsh and Geyer, Thomas and Sarradj, Ennes and Schmidt, Heiko}, title = {Numerical investigation of noise generation by rod-airfoil configuration using DES (SU2) and the FW-H analogy}, series = {25th AIAA/CEAS Aeroacoustics Conference 2019, Delft, The Netherlands, 20 - 24 May 2019, (AIAA 2019-2400)}, journal = {25th AIAA/CEAS Aeroacoustics Conference 2019, Delft, The Netherlands, 20 - 24 May 2019, (AIAA 2019-2400)}, doi = {10.2514/6.2019-2400}, pages = {1 -- 17}, language = {en} } @incollection{MoreauGeyerDoolanetal., author = {Moreau, Danielle J. and Geyer, Thomas and Doolan, Con and Sarradj, Ennes}, title = {Influence of Camber on Wall-Mounted Finite Airfoil Tonal Noise Generation}, series = {Fluid-Structure-Sound Interactions and Control Proceedings of the 4th Symposium on Fluid-Structure-Sound Interactions and Control}, booktitle = {Fluid-Structure-Sound Interactions and Control Proceedings of the 4th Symposium on Fluid-Structure-Sound Interactions and Control}, editor = {Zhou, Yu and Kimura, Motoaki and Peng, Guoyi and Lucey, A. D. and Huang, Lixi}, publisher = {Springer}, address = {Singapore}, isbn = {978-981-10-7541-4}, doi = {10.1007/978-981-10-7542-1_51}, pages = {337 -- 342}, language = {en} } @misc{GeyerWasalaSarradj, author = {Geyer, Thomas and Wasala, Sahan and Sarradj, Ennes}, title = {Experimental Study of Airfoil Leading Edge Combs for Turbulence Interaction Noise Reduction}, series = {Acoustics}, volume = {2}, journal = {Acoustics}, number = {2}, issn = {2624-599X}, doi = {10.3390/acoustics2020014}, pages = {207 -- 223}, language = {en} } @misc{SharmaSarradjSchmidt, author = {Sharma, Sparsh and Sarradj, Ennes and Schmidt, Heiko}, title = {Stochastic modelling of leading-edge noise in time-domain using vortex particles}, series = {Journal of Sound and Vibration}, volume = {Vol. 488}, journal = {Journal of Sound and Vibration}, issn = {0022-460X}, doi = {10.1016/j.jsv.2020.115656}, pages = {30}, language = {en} }