Vibratory loads reduction analysis of advanced active twist rotor blades incorporating single crystal piezoelectric fiber composites

Abstract

This paper attempts to improve the efficiency in reducing vibratory loads of Active Twist Rotor (ATR) blades. In order to elevate the twisting authority of the ATR blade, a new Advanced Active Twist Rotor (AATR-II) blade which utilizes single crystal Macro Fiber Composites (MFC) is considered. In the AATR-II blade design, to find the cross-sectional layout which gives the maximum tip twist, design optimization is introduced. Due to both the high actuation performance of the single crystal MFC and the optimized cross-section configuration, it is expected that the AATR-II blade may reduce the vibratory loads at both fixed- and rotating-systems when much lower input-voltage is applied compared with that used in the previous ATR blades using the Active Fiber Composites (AFC) or the standard MFC. In this paper, vibratory loads reduction analysis of the AATR-II blade in forward flight condition is also conducted. For the forward flight simulation in time domain, the nonlinear flexible multi-body modeling tool, DYMORE, is used. In addition, for the blade control, Individual Blade Control (IBC) mode using sine-dwell signal with control phase is applied. The numerical simulation results show an improved performance and efficiency of the AATR-II blade in reducing the vibratory loads of helicopters. Copyright © 2008 by the American Helicopter Society International, Inc. All right reserved.