Abstract
Delta wing shapes are unique in their structure advantages and aerodynamic characteristics. On supersonic designing, a delta wing shape is often used to reduce drag and achieve the optimal performance. In this study, a commercial software (ANSYS 15) is used to investigate the performance of two delta wing shapes (simple delta wing and cranked arrow delta wing) at different angles of attack (5° to 65°) and different flow speeds (M = 0.15 to 1.4) in order to obtain the lift and drag coefficients, pressure distribution around the investigated wings, and velocity filed. The results indicate that: (i) at subsonic speed (M = 0.15 to 0.8), the lift coefficient for the cranked arrow delta wing increases by about 25%. While the drag coefficient in case of cranked arrow delta wing increases by a value reaches 5%, as the area of the cranked arrow delta wing is less by about 7%, this leads to decreasing drag force for the cranked arrow wing, which improves its performance. The lift and drag coefficients increase with increasing Mach number, the rate of increase is higher in the cranked arrow delta wing. In cranked arrow delta wing, vortex breakdown is delayed than that in simple delta wing, which makes the cranked arrow more stable. In addition, the cut parts from cranked arrow at trailing edge help to avoid the effect of vortex breakdown on the wing. (ii) At supersonic speed (M = 1.2 to M = 1.4), the lift coefficient of the cranked arrow delta wing is higher than that for simple delta wing by about 15%, while the increase in the drag coefficient does not exceed 2%, which increases cranked arrow wing’s performance. The lift and drag coefficients decrease with increasing Mach number, the rate of decrease is higher in the cranked arrow delta wing. In the cranked arrow delta wing as Mach number increases, a better pressure distribution over the wing surface is observed which improves the stability during flight and maneuvering.
Highlights
At low speeds, delta wings generate higher lift than rectangular planform wings, which improves its performance
The computational fluid dynamics (CFD) results for pressure distribution, flow velocity, lift, and drag coefficients were obtained for both simple delta wing and cranked arrow delta wing at different Mach numbers,(M∞ = 0.15, 0.4, 0.8, 1.2, 1.4) and different angles of attack (5o, 25o, 45o, 65o)
The present results for lift and drag coefficients for both simple delta wing and cranked arrow delta wing are illustrated in Figs. (6) to (8)
Summary
Delta wings generate higher lift than rectangular planform wings, which improves its performance. The simple and cranked arrow wings are used in the applications of supersonic and transonic aviation due to its aerodynamic performance and maneuverability at high angles of attack These advantages are due to the vortex generated from the strake wing (or the inboard wing) stabilizes the flow on the main wing (or the outboard wing), while the outboard wing leading edge has a smaller sweepback angle than that of the inboard wing which increases the wing aspect ratio as a whole and low-speed performance is improved. Sforza and Smorto [6] experimentally found that, for a delta wing at the low-speed flow and highly swept angle with sharp leading edges and high angle of attack, there is no vortex axisymmetric and no scale linearly within half of the span or in the region of the axis of vortex rotation They found that viscous character becomes important as maximum flow velocity decreases with downstream distance. A theoretical study using CFD is to be performed to obtain the pressure distribution, flow velocity, lift and drag coefficients and lift to drag ratio for each wing at different Mach numbers and different angles of attack
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
