@article {Baskaran:2018:0736-2935:2140, title = "Reduction of Impinging Noise Issued from Non-Circular Orifices", journal = "INTER-NOISE and NOISE-CON Congress and Conference Proceedings", parent_itemid = "infobike://ince/incecp", publishercode ="ince", year = "2018", volume = "258", number = "5", publication date ="2018-12-18T00:00:00", pages = "2140-2145", itemtype = "ARTICLE", issn = "0736-2935", url = "https://www.ingentaconnect.com/content/ince/incecp/2018/00000258/00000005/art00015", author = "Baskaran, Kabilan and Dhamanekar, Abhijit and K, Srinivasan", abstract = "The present article compares the impingement noise generated due to the impact of jet issued from non-circular devices (triangular, elliptical). Circular jet issued from the orifice with the equivalent area is considered as a reference. The experiments are performed for at various Nozzle pressure ratios ranging from subsonic to supersonic. The NPR variation is performed for nozzle plate spacing, h/d=4.0, and h/d=5.0. Apart from this the effect of impingement plate porosity also studied. The acoustic measurement is carried out in the acoustic far-field region. The effect of a major and minor axis of the elliptical jets and flat and vertex edge of the triangular jets are also studied. The noise measured are compared in terms of Overall sound pressure level, frequency spectra, and acoustic power. It is found that the supersonic impinging tones are eliminated and acoustic power significantly reduced in non-circular orifice jets. Impinging tones are completely eliminated in supersonic flow regimes. In full paper, the effect of non-circular jets and effect of h/d on far-field acoustics explained in a detailed manner.", }