Investigation of Flow Characteristics and Vortex Formations of Lambda Wing at High Angles of Attack

Abstract

It is well known in literature that further stages of flow separation and vortex breakdown around wings can be able to cause stall of wings. These formations must be investigated carefully for new plane types. However, some limited studies are available, especially on lambda wing for high angles of attack. In this study, effect of angle of attack on flow characteristics and vortex breakdown around a lambda wing is investigated with a constant Reynolds number of 10000. Computational fluid dynamic analysis is used and results of high angles of attack of the wing are given up to 45 0 which are not available in literature. Open water channel simulation is used. Vortex breakdown initially begins at an angle of 17 0 and it almost reaches to tip of wing when angle of attack is equal to 25 0. Vortices get stronger at further increments of angle of attack and they become to nearly equal length of wing at 45 0. Rounding effect of leading edges is investigated for decreasing vortex magnitudes. Streamline, particle injection, iso-value of vortices and location of stagnation points are given, and they are discussed in detail.

Numerical Investigations on Low-Speed Aerodynamic Characteristics of Generic Unmanned Combat Aerial Vehicle Configurations

“…The flow over the UCAV at higher angle of attack exhibit high unsteadiness due to vortex breakdown, however the objective of the present study is to compute the aerodynamic performance of the UCAV model and not to investigate the complex vortex breakdown mechanism. It is noteworthy to mention Yavuz [53] established that the steady and mean unsteady results exhibit marginal variation compared to the experiments. Moreover, the vortex location and rotation are similar for both RANS and URANS solutions [15,[53][54][55][56].…”

“…It is noteworthy to mention Yavuz [53] established that the steady and mean unsteady results exhibit marginal variation compared to the experiments. Moreover, the vortex location and rotation are similar for both RANS and URANS solutions [15,[53][54][55][56]. Furthermore, k-w SST performs better in capturing the vortex breakdown with minimal computational time [57].…”