期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
Pitching Moment Generation in an Insect-Mimicking Flapping-Wing System 被引量:4
1
作者 Tri Quang Truong Vu Hoang Phan +1 位作者 Sanjay P. Sane Hoon Cheol Park 《Journal of Bionic Engineering》 SCIE EI CSCD 2014年第1期36-51,共16页
Unlike birds, insects lack control surfaces at the tail and hence most insects modify their wing kinematics to produce control forces or moments while flapping their wings. Change of the flapping angle range is one of... Unlike birds, insects lack control surfaces at the tail and hence most insects modify their wing kinematics to produce control forces or moments while flapping their wings. Change of the flapping angle range is one of the ways to modify wing kinematics, resulting in relocation of the mean Aerodynamic force Center (mean AC) and finally creating control moments. In an attempt to mimic this feature, we developed a flapping-wing system that generates a desired pitching moment during flap- ping-wing motion. The system comprises a flapping mechanism that creates a large and symmetric flapping motion in a pair of wings, a flapping angle change mechanism that modifies the flapping angle range, artificial wings, and a power source. From the measured wing kinematics, we have found that the flapping-wing system can properly modify the flapping angle ranges. The measured pitching moments show that the flapping-wing system generates a pitching moment in a desired direction by shifting the flapping angle range. We also demonstrated that the system can in practice change the longitudinal attitude by generating a nonzero pitching moment. 展开更多
关键词 flapping-wing system pitching moment flapping angle unsteady blade element theory mean aerodynamic center center of gravity
原文传递
Stability Analysis for Projectile with Wrap-Around Fins
2
作者 王成 宁建国 《Journal of Beijing Institute of Technology》 EI CAS 2007年第4期388-392,共5页
Based on the stability theory, numerical simulations and theoretical calculations are performed for a projectile with wrap-around fins. Its stability is analyzed and the flow field is simulated with computational flui... Based on the stability theory, numerical simulations and theoretical calculations are performed for a projectile with wrap-around fins. Its stability is analyzed and the flow field is simulated with computational fluid dynamics method. Consequently, the pitching moment coefficient of the projectile is further investigated under the conditions of Mach number ranging from 0.3 to 0.8, attack angle from 0 to 8° and yaw angle from 0 to 4°. A trajectory equation is established and its trajectory characteristics are also explored. All the results of theoretical analysis, numerical simulation and trajectory equation agree well with each other, which indicates the projectile is flying steadily at the given conditions. These results provide an effective way for judging the stability of the projectile with wrap-around fins. 展开更多
关键词 projectile with wrap-around fins STABILITY pitching moment coefficient numerical simulation trajectory equation
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部