Noise radiation from circular rods at low-moderate Reynolds number

• Autorzy: Kopania Joanna Maria , Bogusławski Grzegorz , Gaj Patryk , Wójciak Kamil
• Języki publikacji: EN

Abstrakty

EN

The well-known dominant sources of airframe noise are associated with unsteadiness of separated and/or vortical flow regions around the high-lift system (flaps, slats) and the aircraft undercarriage (landing gear). Current practical landing gear noise prediction models are individual component - based, which means that the various components are divided into groups according to the frequency range, in which they predominantly radiate noise. Since the far-field noise spectra are approximately Strouhal - based, the emitted frequency is assumed to be directly related to their size: the large elements are responsible for the low frequency region of the spectra, and the small components for the high frequency region. On the basis of such understanding of the noise generation mechanism, the special configurations that lead to considerable noise suppression were proposed. One element of these configurations are rods with different shape and cross section. In this work the situation when circular rods are in area of laminar-turbulent flow were analysed. The measurements were carried out for single circular rod with different diameters to study the noise effect depended on Reynolds number. Far field noise for broad range of Reynolds numbers was also examined depending on distance from the source of noise.

Słowa kluczowe

EN

aeroacoustic noise; circular rod; low Reynolds number

PL

hałas aeroakustyczny; pręt kołowy; niska liczba Reynoldsa

• Wydawca: Poznan University of Technology. Institute of Applied Mechanics
• Czasopismo: Vibrations in Physical Systems
• Rocznik: 2019
• Tom: Vol. 30, nr 1
• Strony: art. no. 2019116
• Opis fizyczny: Bibliogr. 12 poz., fot. kolor., 1 rys., wykr.

Twórcy

autor

Kopania Joanna Maria

• Lodz University of Technology, 266 Piotrkowska Street, 90-924 Lodz, Poland

autor

Bogusławski Grzegorz

• Lodz University of Technology, 266 Piotrkowska Street, 90-924 Lodz, Poland

autor

Gaj Patryk

• Institute of Power Engineering - Thermal Technology Branch "ITC" in Lodz, 113 Dabrowskiego Street, 93-208 Lodz, Poland

autor

Wójciak Kamil

• Institute of Power Engineering - Thermal Technology Branch "ITC" in Lodz, 113 Dabrowskiego Street, 93-208 Lodz, Poland

Bibliografia

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020).