A Comparative Assessment of Various Cavitator Shapes for High-speed Supercavitating Torpedoes: Geometry, Flow-physics and Drag Considerations

IF 1.1 4区工程技术 Q4 MECHANICS

Journal of Applied Fluid Mechanics Pub Date : 2024-07-03 DOI:10.47176/jafm.17.9.2631

K. Gaurav, N. Venkatesh, †. A.Karn

{"title":"A Comparative Assessment of Various Cavitator Shapes for High-speed Supercavitating Torpedoes: Geometry, Flow-physics and Drag Considerations","authors":"K. Gaurav, N. Venkatesh, †. A.Karn","doi":"10.47176/jafm.17.9.2631","DOIUrl":null,"url":null,"abstract":"Modern underwater warfare necessitates the development of high-speed supercavitating torpedoes. Achieving supercavitation involves integrating a cavitator at the torpedo's front, making cavitator design a critical research area. The present study simulated supercavity formation by cavitators of various shapes attached to a heavyweight torpedo. The study involves simulations of thirteen cavitator designs with various geometrical configurations at different cavitation numbers. The simulations employ the VOF multiphase model along with the Schnerr and Sauer cavitation model to analyze supercavitation hydrodynamics. The study examines the supercavity geometry and drag characteristics for individual cavitator designs. The results reveal a significant reduction in skin friction drag by a majority of cavitators. Notably, a disc cavitator at a cavitation number of 0.09 demonstrates a remarkable 92% reduction in the coefficient of skin friction drag. However, the overall drag reduces when incorporating a cavitator, but it introduces additional pressure drag. The study found that the cavitators generating larger supercavities also yield higher pressure drag. Therefore, the supercavity should just envelop the entire torpedo, as excessively small supercavities amplify skin friction drag, while overly large ones elevate pressure drag. Ultimately, the study concludes that selecting the ideal cavitator entails a comprehensive evaluation of factors such as supercavity and torpedo geometry, reductions in skin friction drag and increments in pressure drag.","PeriodicalId":49041,"journal":{"name":"Journal of Applied Fluid Mechanics","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Applied Fluid Mechanics","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.47176/jafm.17.9.2631","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MECHANICS","Score":null,"Total":0}

引用次数: 0

Abstract

Modern underwater warfare necessitates the development of high-speed supercavitating torpedoes. Achieving supercavitation involves integrating a cavitator at the torpedo's front, making cavitator design a critical research area. The present study simulated supercavity formation by cavitators of various shapes attached to a heavyweight torpedo. The study involves simulations of thirteen cavitator designs with various geometrical configurations at different cavitation numbers. The simulations employ the VOF multiphase model along with the Schnerr and Sauer cavitation model to analyze supercavitation hydrodynamics. The study examines the supercavity geometry and drag characteristics for individual cavitator designs. The results reveal a significant reduction in skin friction drag by a majority of cavitators. Notably, a disc cavitator at a cavitation number of 0.09 demonstrates a remarkable 92% reduction in the coefficient of skin friction drag. However, the overall drag reduces when incorporating a cavitator, but it introduces additional pressure drag. The study found that the cavitators generating larger supercavities also yield higher pressure drag. Therefore, the supercavity should just envelop the entire torpedo, as excessively small supercavities amplify skin friction drag, while overly large ones elevate pressure drag. Ultimately, the study concludes that selecting the ideal cavitator entails a comprehensive evaluation of factors such as supercavity and torpedo geometry, reductions in skin friction drag and increments in pressure drag.

查看原文本刊更多论文

用于高速超空化鱼雷的各种空化器形状的比较评估：几何形状、流体物理学和阻力考虑因素

现代水下战争需要研制高速超空化鱼雷。实现超空化需要在鱼雷前部集成空化器，因此空化器的设计是一个关键的研究领域。本研究模拟了安装在重型鱼雷上的各种形状的空化器形成的超空化。研究涉及在不同空化数下对 13 种具有不同几何构造的空化器设计进行模拟。模拟采用 VOF 多相模型以及 Schnerr 和 Sauer 空化模型来分析超空化流体力学。研究考察了各个空化器设计的超空化几何形状和阻力特性。结果表明，大多数空化器都能显著降低表皮摩擦阻力。值得注意的是，空化数为 0.09 的圆盘空化器显著降低了 92% 的表皮摩擦阻力系数。然而，加入空化器后，整体阻力减小了，但却带来了额外的压力阻力。研究发现，产生较大超空腔的空化器也会产生较高的压力阻力。因此，超级空腔应刚好包围整个鱼雷，因为过小的超级空腔会增大表皮摩擦阻力，而过大的超级空腔则会增大压力阻力。最后，研究得出结论，选择理想的空化器需要对超级空腔和鱼雷的几何形状、皮肤摩擦阻力的减小和压力阻力的增大等因素进行综合评估。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Journal of Applied Fluid Mechanics THERMODYNAMICS-MECHANICS

CiteScore

2.00

自引率

20.00%

发文量

138

审稿时长

>12 weeks

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) .