Vortex Structure Analysis of Grooved Surface Flow Loss. Issue 6 (March 2019)

• Record Type: Journal Article
• Authors: Liu, Mei; Li, Shuguang; Zhang, Kaishun; Yang, Hongyue; Wang, Songling
• Is Part Of: IOP conference series. Volume 242:Issue 6(2019)
• Publication Date: 2019-03
• Subjects: Earth sciences -- Periodicals; Environmental sciences -- Congresses; Environmental sciences -- Periodicals; 550.5
• DOI: 10.1088/1755-1315/242/6/062035
• Languages: English
• ISSNs: 1755-1307

Abstract

Abstract: Large eddy simulations were used to study the effect of groove structures on rotational motion of fluid in wall turbulence, from the perspective of coherent structures. The results show that groove structures reduce the per unit normal height internal velocity gradient in the near-wall region and decrease shear stress and viscous resistance. Concurrently, owing to the decrease in the velocity gradient, shear action is weakened, and the vortices' level of stretch is reduced in the near-wall region of the grooved surface. The groove structures change the distribution of the shear layers in the boundary layer and increase the stability of the strips. The reduction of spanwise vorticities delayed the formation of hairpin vortices caused by the instability of strips and so on; and the energy dissipation is effectively reduced in the flow process.