Experimental Study on Slat Noise from 30P30N Three-Element High-Lift Airfoil at JAXA Hard-Wall Lowspeed Wind Tunnel

Assessment of Slat Noise Predictions for 30P30N High-Lift Configuration from BANC-III Workshop

“…In return, however, one must accept the resulting challenges in comparing computational data with wind tunnel measurements, since the aerodynamics of high-lift configurations in test sections of modest size (the kind that is typically available for the in-depth fundamental measurements targeted in the BANC workshops) is significantly influenced by the presence of tunnel walls. 19,20,39 The requirements of a benchmark dataset will not be achieved in all cases, especially in a single round of workshops, and hence, the title of the BANC series reflects the quest for the benchmark datasets and the collective journey towards that goal.…”

“…A brief description of each experiment is given below, followed by observations about the computational contributions. For additional details of the measurements, the reader is referred to the papers by Pascioni et al 19 and Murayama et al 20 Closed-wall wind tunnel tests in the Florida State Aeroacoustic Tunnel (FSAT) with a 0.914 m × 1.219 m × 3.048 m (Height × Width × Length) test section used a combination of surface and offbody measurements to characterize the slat cove flow field. Measured mean surface pressures compared well with numerical predictions for the free-air configuration obtained using time-accurate simulations.…”

“…Measurements of surface pressure fluctuations and acoustic radiation were made for the BANC-III workshop 19,20 as described in Section III of this paper, with plans to acquire more in-depth data in follow-on tests. The future measurements will also address the specific needs identified during BANC-III, with an emphasis on quantifying the robustness of the experimental findings and assessing the uncertainties via measurements of the same configuration in different facilities.…”

“…Three other teams contributed complementary information derived from previously conducted simulations for the same geometry and either the same or related flow conditions. Measurements were performed in wind tunnel facilities at Florida State University 19 in the USA and at JAXA 20 in Japan. The nominal flow conditions of interest involved a Mach number of 0.17, Reynolds number based on stowed chord of 1.71 million, and an equivalent free-air angle of attack (AoA) equal to 5.5 degrees.…”

Efeito aeroacústico de excrescências bidimensionais na cova de um eslate

“…Especula-se que possa ser alguma limitação do próprio processamento de sinais (algorítimo utilizado), tendo em vista que os trabalhos encontrados na literatura que apresentam mapas de beamforming para fontes em eslates, (CHOUDHARI et al, 2002;IMAMURA et al, 2009;MURAYAMA et al, 2014;URA et al, 2010), não trazem mapas para mais baixas frequências e também não implementam algoritmos de deconvolução tal como o DAMAS, apenas utilizam beamforming convencional para estimar a forma e localização das fontes de ruído. Kröber (2014) diz que quando utilizando túnel de seção fechada, para baixas frequências o sinal obtido na antena de microfones está contaminado com o ruído de fundo de túnel e da camada-limite das paredes do túnel, prejudicando a reconstrução das fontes acústicas com algorítimos de beamforming.…”