نوع مقاله : مقاله پژوهشی
1 گروه مکانیک، واحد علوم و تحقیقات دانشگاه آزاد اسلامی، تهران، ایران.
2 مدیر گروه مکانیک، دانشکده مکانیک برق و کامپیوتر، واحد علوم و تحقیقات دانشگاه آزاد اسلامی، تهران، ایران.
3 عضو گروه مکانیک، دانشگاه علم و صنعت
عنوان مقاله [English]
Recently many researches are being conducted on flying robots. One field is to design the flapping kinematics to achieve better performance and maneuverability. Better maneuverability is achievable via variable wing geometry and for better performance, the effect of wing’s angle of attack can be considered. Positive effect of angle of attack is studied before however, variations of angle of attack in a flapping cycle is the main subject in this paper. Three dimensional model of wing and body is inserted in ANSYS-FLUENT and aerodynamic lift force is simulated and calculated. Each wing is modeled as a two-part mechanism with relative motion. Comparing to previous studies, wings’ angle of attack periodically changes which is more similar to natural flapping and improves efficiency. Change rate of this variations is equal to flapping frequency. At first numerical simulations are verified by a previous study on a wing with fixed angle of attack. Then the wing with variable angle of attack is numerically simulated. Results show that an improvement of the lift force for more than ten percent is achievable by this method.