Computational and Experimental Analysis of Effect of Leading Edge of a Delta Wing in Laminar and Turbulent Flows
A delta wing is a triangular planform wing used on high
speed aircrafts and reentry vehicles. Due to its high sweep
angle, it is used on supersonic aircrafts to delay the drag
divergence Mach number and to gain higher lift values at
lower speeds during landing and takeoff. The main advantage of the delta wing is the generation of vortex lift which is higher than any type of wing of same area and sweep angle. At medium to high angles of attack, the vortex formation shows an unsteady flipping phenomenon by which aircraft control becomes difficult and at some high angle of attack, one of these vortices bursts or mixes with the flow creating sudden loss of lift. This is also called vortex shedding. Due to the vortex shedding, aircraft suddenly stalls and becomes unstable creating a difficulty in operating the control surfaces for the pilot. The present study discusses about the nature of vortex on the delta wing and the leading edge profile influence on vortex nature in laminar and tubulent flows computationally, mostly in a qualitative context. An experiment of oil flow visualization was also performed in order to prove the vortex formation on three delta wings with different leading edge profiles. The on time CM graphs obtained during computation shows variable fluctuations of vortices for laminar and turbulent flows with the same model for the same input conditions.