caa a22 4500 606198563 CHVBK 20210128100934.0 cr unu---uuuuu 210128e20150501xx s 000 0 eng 10.1007/s00348-015-1967-x doi (NATIONALLICENCE)springer-10.1007/s00348-015-1967-x Sound source mechanisms in under-expanded impinging jets [Elektronische Daten] [Giorgia Sinibaldi, Luca Marino, Giovanni Romano] Experiments on the aeroacoustics of an under-expanded supersonic jet impinging on a flat plate are presented and thoroughly discussed. A wide range of nozzle pressure ratios and of nozzle-to-plate distances has been analyzed with particular attention to the behavior of the discrete component of the noise. The investigation has been carried out by means of acoustic, particle image velocimetry and wall pressure measurements. The analysis of the relationship between the acoustic data and the fluid dynamic fields allows to examine the different source mechanisms of the discrete component of the noise and to evaluate the link between the jet flow structure and the acoustic tone features. Specifically, two ranges of nozzle pressure ratio have been observed showing different acoustic behaviors, characterized by distinct mechanisms of discrete noise generation. These regions are separated by a range of nozzle pressure ratios where impinging tones are not observed. The present experimental data extend previously published results, improving the analysis of the connection between fluid dynamic and acoustic fields and leading to a better comprehension of the impinging tone source mechanisms. Springer-Verlag Berlin Heidelberg, 2015 Sinibaldi Giorgia Department of Mechanical and Aerospace Engineering, La Sapienza, Via Eudossiana 18, 00184, Rome, Italy aut Marino Luca Department of Mechanical and Aerospace Engineering, La Sapienza, Via Eudossiana 18, 00184, Rome, Italy aut Romano Giovanni Department of Mechanical and Aerospace Engineering, La Sapienza, Via Eudossiana 18, 00184, Rome, Italy aut Experiments in Fluids Springer Berlin Heidelberg 56/5(2015-05-01), 1-14 0723-4864 56:5<1 2015 56 348 https://doi.org/10.1007/s00348-015-1967-x text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00348-015-1967-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sinibaldi Giorgia Department of Mechanical and Aerospace Engineering, La Sapienza, Via Eudossiana 18, 00184, Rome, Italy aut NATIONALLICENCE 700 1- Marino Luca Department of Mechanical and Aerospace Engineering, La Sapienza, Via Eudossiana 18, 00184, Rome, Italy aut NATIONALLICENCE 700 1- Romano Giovanni Department of Mechanical and Aerospace Engineering, La Sapienza, Via Eudossiana 18, 00184, Rome, Italy aut NATIONALLICENCE 773 0- Experiments in Fluids Springer Berlin Heidelberg 56/5(2015-05-01), 1-14 0723-4864 56:5<1 2015 56 348