期刊
JOURNAL OF THE AMERICAN HELICOPTER SOCIETY
卷 57, 期 4, 页码 -出版社
AMER HELICOPTER SOC INC
DOI: 10.4050/JAHS.57.042003
关键词
-
资金
- Office of Naval Research
A primary design goal with a coaxial rotor is to minimize the combined sources of losses on the upper and lower rotors that have their source in aerodynamic interference. To this end, parametric studies were conducted using a free-vortex wake method to study the aerodynamic interference effects of changing interrotor spacing, blade twist rates, and blade planform on the interdependent loads produced on the upper and lower rotors, respectively. A formal, multistep optimization process was then conducted by coupling the aerodynamic method to an optimization approach based on the method of feasible directions, the goal being to expeditiously find the individual blade geometries that would give the highest levels of efficiency from the coaxial as a system. Because of the inherent aerodynamic differences between the upper and lower rotors of a coaxial, it is shown that the best performing coaxial rotors may require the use of different blade shapes on each rotor, but substantially different blade designs may also achieve similar values of aerodynamic efficiency. It is also shown that the nonconvexity of the design problem for a coaxial rotor may limit the usefulness of formal optimization methods, and extensive parametric studies may still be required in the process of design.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据