Microphone Array Measurement in European Transonic Wind Tunnel at Flight Reynolds Numbers
| Autor: | Thomas Ahlefeldt |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Microphone array
Engineering cryogenic pressurized wind tunnel Acoustics Aerospace Engineering 02 engineering and technology 01 natural sciences microphone array high-lift 010305 fluids & plasmas Physics::Fluid Dynamics symbols.namesake 0203 mechanical engineering 0103 physical sciences Airframe Experimentelle Verfahren GO aeroacoustics Aerospace engineering Sound pressure Wind tunnel 020301 aerospace & aeronautics Angle of attack business.industry Reynolds number Mach number symbols real-flight/full-scale Reynolds number business Transonic |
| Zdroj: | AIAA Journal. 55:36-48 |
| ISSN: | 1533-385X 0001-1452 |
| Popis: | This paper presents an experimental investigation of small-scale model airframe noise at various Reynolds numbers up to the real-flight case. The study consists of data acquired with a microphone array in the European Transonic Windtunnel (ETW). The advantage of the ETW is to enable testing simultaneously at cryogenic temperatures and increased pressure levels, which extends the range of achievable Reynolds numbers up to those pertaining to full-scale flight conditions. At the German Aerospace Center (DLR), the microphone-array measurement technique has been further developed to perform measurements under combined cryogenic and pressurized conditions. For this purpose, a microphone-array consisting of 96 microphones was designed and constructed. In this paper, aeroacoustic results are presented for various Reynolds numbers up to the real-flight case on an Airbus K3DY half-model of scale 1:13.6. The results showed significant Reynolds number and Mach number dependency for various sources. Of particular note are various dominant sources appearing on the flap at real-flight Reynolds numbers. To the authors knowledge, this is the first time that airframe noise data for a small-scale model have been acquired at real-flight Reynolds numbers. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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