{"title":"利用凹槽片操纵超音速喷气机","authors":"A. K. Mali, T. Jana, M. Kaushik, S. Thanigaiarasu","doi":"10.47176/jafm.17.05.2326","DOIUrl":null,"url":null,"abstract":"This study experimentally evaluated the mixing augmentation of twin tabs mounted along a diameter at the outlet of a convergent-divergent Mach 1.62 circular nozzle. The usefulness of the plain and grooved tabs is examined at various expansion levels prevailing at nozzle outlet. The tab's performance is assessed through pitot pressure distribution measured along and perpendicular to the jet centerline at different nozzle pressure ratios (NPRs). The shadowgraph technique visualized the shocks and expansion fans in uncontrolled and controlled jets. With the introduction of uncorrugated or plain tabs at the nozzle outlet operating under overexpanded conditions corresponding to NPR 4, the supersonic length (SL) was decreased only by 35.4%. On the other hand, the corrugated or grooved tabs under similar conditions decreased the SL substantially. Interestingly, the performance of grooved tabs was best at underexpanded conditions associated with NPR 6, where the SL was reduced by about 88%. The pressure profiles also established the superiority of tabs with grooved edges in mixing augmentation without introducing any significant asymmetry to the flow field. In addition, the Shadowgraph images also confirmed the weakening of shock strength and reduction of shock-cell length in the case of grooved tabs at the nozzle exit compared to the plain","PeriodicalId":49041,"journal":{"name":"Journal of Applied Fluid Mechanics","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":"{\"title\":\"Manipulation of Supersonic Jet using Grooved Tabs\",\"authors\":\"A. K. Mali, T. Jana, M. Kaushik, S. Thanigaiarasu\",\"doi\":\"10.47176/jafm.17.05.2326\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"This study experimentally evaluated the mixing augmentation of twin tabs mounted along a diameter at the outlet of a convergent-divergent Mach 1.62 circular nozzle. The usefulness of the plain and grooved tabs is examined at various expansion levels prevailing at nozzle outlet. The tab's performance is assessed through pitot pressure distribution measured along and perpendicular to the jet centerline at different nozzle pressure ratios (NPRs). The shadowgraph technique visualized the shocks and expansion fans in uncontrolled and controlled jets. With the introduction of uncorrugated or plain tabs at the nozzle outlet operating under overexpanded conditions corresponding to NPR 4, the supersonic length (SL) was decreased only by 35.4%. On the other hand, the corrugated or grooved tabs under similar conditions decreased the SL substantially. Interestingly, the performance of grooved tabs was best at underexpanded conditions associated with NPR 6, where the SL was reduced by about 88%. The pressure profiles also established the superiority of tabs with grooved edges in mixing augmentation without introducing any significant asymmetry to the flow field. In addition, the Shadowgraph images also confirmed the weakening of shock strength and reduction of shock-cell length in the case of grooved tabs at the nozzle exit compared to the plain\",\"PeriodicalId\":49041,\"journal\":{\"name\":\"Journal of Applied Fluid Mechanics\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.1000,\"publicationDate\":\"2024-05-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"1\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Applied Fluid Mechanics\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.47176/jafm.17.05.2326\",\"RegionNum\":4,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"MECHANICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Applied Fluid Mechanics","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.47176/jafm.17.05.2326","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MECHANICS","Score":null,"Total":0}
This study experimentally evaluated the mixing augmentation of twin tabs mounted along a diameter at the outlet of a convergent-divergent Mach 1.62 circular nozzle. The usefulness of the plain and grooved tabs is examined at various expansion levels prevailing at nozzle outlet. The tab's performance is assessed through pitot pressure distribution measured along and perpendicular to the jet centerline at different nozzle pressure ratios (NPRs). The shadowgraph technique visualized the shocks and expansion fans in uncontrolled and controlled jets. With the introduction of uncorrugated or plain tabs at the nozzle outlet operating under overexpanded conditions corresponding to NPR 4, the supersonic length (SL) was decreased only by 35.4%. On the other hand, the corrugated or grooved tabs under similar conditions decreased the SL substantially. Interestingly, the performance of grooved tabs was best at underexpanded conditions associated with NPR 6, where the SL was reduced by about 88%. The pressure profiles also established the superiority of tabs with grooved edges in mixing augmentation without introducing any significant asymmetry to the flow field. In addition, the Shadowgraph images also confirmed the weakening of shock strength and reduction of shock-cell length in the case of grooved tabs at the nozzle exit compared to the plain
期刊介绍:
The Journal of Applied Fluid Mechanics (JAFM) is an international, peer-reviewed journal which covers a wide range of theoretical, numerical and experimental aspects in fluid mechanics. The emphasis is on the applications in different engineering fields rather than on pure mathematical or physical aspects in fluid mechanics. Although many high quality journals pertaining to different aspects of fluid mechanics presently exist, research in the field is rapidly escalating. The motivation for this new fluid mechanics journal is driven by the following points: (1) there is a need to have an e-journal accessible to all fluid mechanics researchers, (2) scientists from third- world countries need a venue that does not incur publication costs, (3) quality papers deserve rapid and fast publication through an efficient peer review process, and (4) an outlet is needed for rapid dissemination of fluid mechanics conferences held in Asian countries. Pertaining to this latter point, there presently exist some excellent conferences devoted to the promotion of fluid mechanics in the region such as the Asian Congress of Fluid Mechanics which began in 1980 and nominally takes place in one of the Asian countries every two years. We hope that the proposed journal provides and additional impetus for promoting applied fluids research and associated activities in this continent. The journal is under the umbrella of the Physics Society of Iran with the collaboration of Isfahan University of Technology (IUT) .