Analysis of a Multiflap Control System for a Swashplateless Rotor

Abstract

An analytical study was conducted examining the feasibility of a swashplateless rotor controlled through two trailing edge flaps (TEF), where the cyclic and collective controls were provided by separate TEFs. This analysis included a parametric study examining the impact of various design parameters on TEF deflections. Blade pitch bearing stiffness; blade pitch index; and flap chord, span, location, and control function of the inboard and outboard flaps were systematically varied on a utility-class rotorcraft trimmed in steady level flight. Gradient-based optimizations minimizing flap deflections were performed to identify single-and two-TEF swashplateless rotor designs. Steady, forward and turning flight analyses suggest that a two-TEF swashplateless rotor where the outboard flap provides cyclic control and inboard flap provides collective control can reduce TEF deflection requirements without a significant impact on power, compared to a single-TEF swashplateless rotor design.

Design and optimisation of an aerofoil with active continuous trailing-edge flap

“…Its potential applications are similar to the widely studied Discrete Trailing-Edge Flap (DTEF) (4) and Active Twist Rotor (ATR) (5,6) , including active control of helicopter rotor vibration and noise, performance improvements and in-flight rotor blade tracking. In addition, the CTEF is being investigated as the potential device for swashplateless rotor control (7) , which requires relatively high control authority.…”