Effect of ring on the flow unsteadiness of slender body at α = 50

• Published in: Journal of the Brazilian Society of Mechanical Sciences and Engineering Vol. 45; no. 3
• Main Authors: Karn, P. K., Das, S., Kumar, P.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2023; Springer Nature B.V
• Subjects: Angle of attack; CAD; Computer aided design; Diameters; Engineering; Fluid flow; High angle of attack; Mechanical Engineering; Reynolds number; Slender bodies; Technical Paper; High angle of attack; Slender body; Unsteady flow
• ISSN: 1678-5878; 1806-3691
• DOI: 10.1007/s40430-023-04101-4

Flow investigations were made on the slender body having a 3.5 calibre ogive nose and a length-to-diameter ( L / D ) ratio of 16 at an angle of attack of 50° and a freestream velocity of 17 m/s which corresponds to a diametric Reynolds number of 29,000. Experiments consisted of the measurement of velocity and pressure fluctuations at different stations of the slender body. Commercial software ANSYS Fluent was utilized for computations. The literature indicated that a rectangular cross-sectioned ring placed at a distance of 3.5 times the diameter from the tip was used to reduce the side force of the slender body at higher angles of attack. The present work aims to investigate the effect of the ring on the unsteadiness in the flow behaviour of the slender body at a high angle of attack. Results indicated that the use of a ring leads to the onset of a localized wake disturbance downstream of the ring. The existence of moderate and higher-order frequencies could be observed in the wake. Computed results too indicated the change in the flow behaviour due to the presence of rings.