Computational Investigation of Vertical Stabilizer with Vortex Generators and Dorsal Fin

Abstract

This paper describes methods to improve the performance of a vertical stabilizer in terms of yawing moment with corotating blade-type vortex generators and a dorsal fin over a wide range of sideslip angles. A vertical stabilizer designed by ONERA was mounted on the NASA Common Research Model to investigate the performance of sets of vortex generators and dorsal fins at several rudder deflection angles. Computational fluid dynamics simulations were performed to reveal basic flow characteristics of the vertical stabilizer, including its rudder, and to understand how vortices generated around the vortex generators and dorsal fins interact with the leading-edge separation vortex and boundary layer on the vertical stabilizer and how the vortices improve the lateral performance of the vertical stabilizer. Wind-tunnel tests were also conducted to validate the computational results. Vortex generators improved the performance of the vertical stabilizer slightly at low sideslip angles by reducing flow separation on the rudder, and a dorsal fin assisted greatly at high sideslip angles due to two vortices it induced: the primary dorsal fin vortex and the leading-edge separation vortex.