{"title":"雷诺数和射流噪声标度","authors":"Aharon Z. Karon, K. K. Ahuja","doi":"10.1177/1475472x231199188","DOIUrl":null,"url":null,"abstract":"The Reynolds number and Mach number are classical quantities used to determine the similarity of aerodynamic flows. Existing studies on the role of Reynolds Number on jet noise show inconsistent results, casting doubt on how small a nozzle diameter can be for the classical jet noise scaling laws to hold. A systematic study was therefore undertaken to resolve this issue. The Reynolds number of jet flows was adjusted using a Mach number variation between 0.4 and 0.8, and nozzle-exit diameters of 0.25, 0.5, and two inches. When the jet noise measurements were normalized, spectral collapse was observed for the spectra across the whole Reynolds number range. It was found that the Reynolds number does not have a significant effect on jet noise, and jet noise can be scaled from even the smallest of nozzle to larger nozzles.","PeriodicalId":49304,"journal":{"name":"International Journal of Aeroacoustics","volume":" ","pages":""},"PeriodicalIF":1.2000,"publicationDate":"2023-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Reynolds number and jet noise scaling\",\"authors\":\"Aharon Z. Karon, K. K. Ahuja\",\"doi\":\"10.1177/1475472x231199188\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The Reynolds number and Mach number are classical quantities used to determine the similarity of aerodynamic flows. Existing studies on the role of Reynolds Number on jet noise show inconsistent results, casting doubt on how small a nozzle diameter can be for the classical jet noise scaling laws to hold. A systematic study was therefore undertaken to resolve this issue. The Reynolds number of jet flows was adjusted using a Mach number variation between 0.4 and 0.8, and nozzle-exit diameters of 0.25, 0.5, and two inches. When the jet noise measurements were normalized, spectral collapse was observed for the spectra across the whole Reynolds number range. It was found that the Reynolds number does not have a significant effect on jet noise, and jet noise can be scaled from even the smallest of nozzle to larger nozzles.\",\"PeriodicalId\":49304,\"journal\":{\"name\":\"International Journal of Aeroacoustics\",\"volume\":\" \",\"pages\":\"\"},\"PeriodicalIF\":1.2000,\"publicationDate\":\"2023-09-06\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"International Journal of Aeroacoustics\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.1177/1475472x231199188\",\"RegionNum\":4,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"ACOUSTICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Aeroacoustics","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1177/1475472x231199188","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ACOUSTICS","Score":null,"Total":0}
The Reynolds number and Mach number are classical quantities used to determine the similarity of aerodynamic flows. Existing studies on the role of Reynolds Number on jet noise show inconsistent results, casting doubt on how small a nozzle diameter can be for the classical jet noise scaling laws to hold. A systematic study was therefore undertaken to resolve this issue. The Reynolds number of jet flows was adjusted using a Mach number variation between 0.4 and 0.8, and nozzle-exit diameters of 0.25, 0.5, and two inches. When the jet noise measurements were normalized, spectral collapse was observed for the spectra across the whole Reynolds number range. It was found that the Reynolds number does not have a significant effect on jet noise, and jet noise can be scaled from even the smallest of nozzle to larger nozzles.
期刊介绍:
International Journal of Aeroacoustics is a peer-reviewed journal publishing developments in all areas of fundamental and applied aeroacoustics. Fundamental topics include advances in understanding aeroacoustics phenomena; applied topics include all aspects of civil and military aircraft, automobile and high speed train aeroacoustics, and the impact of acoustics on structures. As well as original contributions, state of the art reviews and surveys will be published.
Subtopics include, among others, jet mixing noise; screech tones; broadband shock associated noise and methods for suppression; the near-ground acoustic environment of Short Take-Off and Vertical Landing (STOVL) aircraft; weapons bay aeroacoustics, cavity acoustics, closed-loop feedback control of aeroacoustic phenomena; computational aeroacoustics including high fidelity numerical simulations, and analytical acoustics.