Aerodynamic Analysis Of Winglet With Variable Cant Angle

Winglet can reduce the induced drag during the flight which is very important for the transport aircrafts, as the winglet can improve their aerodynamic performance. But traditional winglets are designed for the cruise phase, for non-cruise phase such as take-off phase, the reduction of drag is not well. During the various parameters that affect the aerodynamic performance, cant angle is the most important. Currently, the various winglets that can be chose to installer on wings whose cant angle are fixed, for non-cruise phase, even though they can improvement the aerodynamic performance but less optimal. This paper mainly studies the impact of cant angle on the aerodynamic performance of the wing, in order to find the optimal cant angle of different flight phase, to maximize the improvement of the aerodynamic performance.In this paper, CFD software FLUENT and GAMBIT will be used to create a series of cant angle gradient wing models, by analyzing the changes of lift coefficient and drag coefficient under specific flight conditions, with the limit that wing root bending moment increases less than 3%, to determinate the best range of cant angle for take-off phase and climb phase.This paper is divided into two parts. The first part lies in introduction of resistant theory and principles of drag reduction of winglets. The second part lies in software simulation and analysis of the result. Studies have shown that by increasing the cant angle of winglet, the lift-drag ratio will increase during cruise, take-off and climb phases, but also the wing root bending moment will increase at the same time. By limiting the amount of increase in the wing root bending moment, the cant angle of winglet is limited to 12 degree to cruise phase, 42 degree during take-off phase and 23 degree to climb phase, the aerodynamic performance of the wing will be maximized. This will help to reduce fuel consumption, reduce aircraft operating costs, reduce environmental pollution and even reduce noise pollution which is very important to airlines operators.