本文考慮尾流效應與葉片拍動(包含collective flapping及cyclic flapping)的相互影響:藉由結合旋翼的空氣動力及尾流動力耦合系統且將葉片外形及拍動對升力的影響回饋到非穩態空氣動力系統以求得更精確的預估空氣動力特性。由本文的結果得知,葉片做collective flapping時旋翼圓盤上升力的分佈較葉片不做抽動時爲小;而由於相位差的影響,使得葉片做cyclic flapping時的旋翼圓盤上升力分佈也較collective flapping者爲小。 An analytic model and numerical scheme have been developed to predict the aerodynamic loads on helicopter rotors due to blade flapping in hover and forward flight. The Peters' finite state inflow theory is chosen for a wake modeling. The blade element theory and lifting line theory are used to formulate the aerodynamic forces for a blade- The aerodynamic system that we deal with in this paper is a closed loop system, since we consider the feedback of wake oscillating which will affect the lift change. Both collective and cyclic flapping with wake effects were also considered. Results show that the collective flapping case has less chord-wise lift distribution than a non-flapping motion. Due to different phases will cancel each other and reduce the lift, the cyclic flapping motion has less lift distribution than collective motion.
關聯:
中國航空太空學會學刊=Transactions of the Aeronautical and Astronautical Society of the Republic of China 29(3),頁203-215