Study on Performance Enhancement of Electrically Controlled Rotor Based on 2/rev Flap Input

摘要

Electrically Controlled Rotor (ECR) system has been demonstrated in the primary control of helicopter.rnWithout the restraint of the swashplate, ECR is also an efficient means to enhance the rotor performance byrnapplying higher harmonic flap input. In order to investigate the potential of 2/rev flap input to enhancernECR performance, corresponding aerodynamic model of the ECR rotor and flight dynamic model of thernECR helicopter are established, in which the variation of ECR aerodynamic characteristic due to therndeflection of trailing edge flap is emphasized. The analytical study is accomplished by simulating the ECRrnhelicopter in trimmed flight for various combinations of takeoff weight, flight speed, and amplitude andrnphase angle of the 2/rev flap input. By studying the variation of the profile drag distribution over the rotorrndisk in detail, the physical essence through which 2/rev flap input affects the ECR power is explored.rnSubsequently, the parametric study of the blade pre-index angle affecting power reduction is conducted.rnFinally, the effectiveness of ECR approach for power reduction is compared with that of the conventionalrnIndividual Blade Control (IBC) approach. The simulation results show the potential of the ECR system forrnpower reduction.