{"title":"Effects of a splitter plate on a wingsail for aerodynamic lift enhancement","authors":"Xiao Song , Yuezhang Xia , Peiliang Li","doi":"10.1016/j.euromechflu.2025.204351","DOIUrl":null,"url":null,"abstract":"<div><div>This study investigates the aerodynamic effects of a rigid splitter plate mounted on a two-element wingsail at a chord Reynolds number of <span><math><mrow><mn>1.4</mn><mo>×</mo><msup><mrow><mn>10</mn></mrow><mrow><mn>5</mn></mrow></msup></mrow></math></span>. The splitter plate, serving as a flow control device, is specifically designed for a wingsail operating at an angle of attack of <span><math><mrow><mn>30</mn><mo>°</mo></mrow></math></span> with a flap deflection of <span><math><mrow><mn>50</mn><mo>°</mo></mrow></math></span>, aiming to reduce the no-sail zone of autonomous sailboats. Two-dimensional Unsteady Reynolds-Averaged Navier–Stokes (2D URANS) simulations are conducted to evaluate the effects of splitter plate length (<span><math><msup><mrow><mi>L</mi></mrow><mrow><mo>*</mo></mrow></msup></math></span>) and attachment position (<span><math><msup><mrow><mi>P</mi></mrow><mrow><mo>*</mo></mrow></msup></math></span>) on aerodynamic performance. Results show that the splitter plate can improve the lift-to-drag ratio by up to 39 % when <span><math><mrow><msup><mrow><mi>P</mi></mrow><mrow><mo>*</mo></mrow></msup><mo>=</mo><mn>0.5</mn></mrow></math></span> and <span><math><mrow><msup><mrow><mi>L</mi></mrow><mrow><mo>*</mo></mrow></msup><mo>=</mo><mn>0.1</mn></mrow></math></span>. For shorter splitter plates (<span><math><mrow><msup><mrow><mi>L</mi></mrow><mrow><mo>*</mo></mrow></msup><mo>≤</mo><mn>0.04</mn></mrow></math></span>), the recirculation region over the suction side is suppressed, thereby weakening the lifting vortex and reducing the lift coefficient. As <span><math><msup><mrow><mi>L</mi></mrow><mrow><mo>*</mo></mrow></msup></math></span> increases, the vortex upstream of the splitter plate grows in both size and strength and intrudes into the recirculation region. Consequently, the lifting vortex is intensified due to its interactions with the vortex upstream of the splitter plate and the shear layer above the wingsail. Furthermore, the lifting vortex is displaced closer to the upper surface of the wingsail due to the limited space between the shear layer and the suction surface, resulting in an increase in the lift coefficient. This article uncovers the mechanisms through which the splitter plate enhances lift and demonstrates the feasibility of employing it as a passive flow control strategy to improve aerodynamic performance under specific sail missions and operating conditions.</div></div>","PeriodicalId":11985,"journal":{"name":"European Journal of Mechanics B-fluids","volume":"114 ","pages":"Article 204351"},"PeriodicalIF":2.5000,"publicationDate":"2025-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"European Journal of Mechanics B-fluids","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0997754625001323","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MECHANICS","Score":null,"Total":0}
引用次数: 0
Abstract
This study investigates the aerodynamic effects of a rigid splitter plate mounted on a two-element wingsail at a chord Reynolds number of . The splitter plate, serving as a flow control device, is specifically designed for a wingsail operating at an angle of attack of with a flap deflection of , aiming to reduce the no-sail zone of autonomous sailboats. Two-dimensional Unsteady Reynolds-Averaged Navier–Stokes (2D URANS) simulations are conducted to evaluate the effects of splitter plate length () and attachment position () on aerodynamic performance. Results show that the splitter plate can improve the lift-to-drag ratio by up to 39 % when and . For shorter splitter plates (), the recirculation region over the suction side is suppressed, thereby weakening the lifting vortex and reducing the lift coefficient. As increases, the vortex upstream of the splitter plate grows in both size and strength and intrudes into the recirculation region. Consequently, the lifting vortex is intensified due to its interactions with the vortex upstream of the splitter plate and the shear layer above the wingsail. Furthermore, the lifting vortex is displaced closer to the upper surface of the wingsail due to the limited space between the shear layer and the suction surface, resulting in an increase in the lift coefficient. This article uncovers the mechanisms through which the splitter plate enhances lift and demonstrates the feasibility of employing it as a passive flow control strategy to improve aerodynamic performance under specific sail missions and operating conditions.
期刊介绍:
The European Journal of Mechanics - B/Fluids publishes papers in all fields of fluid mechanics. Although investigations in well-established areas are within the scope of the journal, recent developments and innovative ideas are particularly welcome. Theoretical, computational and experimental papers are equally welcome. Mathematical methods, be they deterministic or stochastic, analytical or numerical, will be accepted provided they serve to clarify some identifiable problems in fluid mechanics, and provided the significance of results is explained. Similarly, experimental papers must add physical insight in to the understanding of fluid mechanics.