Lag-damping of the nonlinear blade-wake coupled system in hover
學年 89
學期 2
發表日期 2001-05-21
作品名稱 Lag-damping of the nonlinear blade-wake coupled system in hover
作品名稱（其他語言）
著者 Wang, Yi-Ren; Pong, Hui-Yueng; Chang, Hong-Wen
作品所屬單位 淡江大學航空太空工程學系
出版者 臺南市：成功大學
會議名稱 第四屆太平洋國際航太科技研討會=The Fourth Pacific International Conference on Aerospace Science and Technology
會議地點
摘要 The lead-lag mode is the most sensitive motion in a helicopter rotoraeroelastic analysis. The stability characteristics of a lag mode in arotor system can be observed through the eigenvalues. The resonancephenomenon can be predicted by eigen-analysis as well. This paper usesanalytic methods to integrate the wake dynamics, blade aerodynamics,and nonlinear composite rotor blade flap-lag-torsion structuraldynamics in the form of a coupled system. Only the homogeneousisotropic material blade will be studied in this paper in order tomake a preliminary investigation of a wake-rotor interaction and thecompatibility of the composite blade equation. The Galerkin's methodand the Duncan's polynomial are used to resolve the equations. Thecoupled nonlinear system is separated into equilibrium and disturbant(dynamic) states. The equilibrium state is solved by using nonlinearsolves. The system's flap-lag-torsion eigen-equations are formulatedby the combination of the equilibrium coefficients and the disturbantequations. The Floquet's theory is used to derive the systemeigenvalues. The nonlinear phenomenon will be investigated througheigen-analysis, especially for quasi-linear resonance. Various lagfrequencies (stiffness) of the isotropic rotor blades are studied inthis paper. The equilibrium results show that the wake has strongeffects in the blade tip displacements in higher blade pitch angles.The eigen-analysis of the lag damping shows the eigenvalue veeringphenomenon occurs when pitch angle is 8 degrees. All of these may bedue to the wake effects in the rotor-wake coupled system. The lead-lag mode is the most sensitive motion in a helicopter rotoraeroelastic analysis. The stability characteristics of a lag mode in arotor system can be observed through the eigenvalues. The resonancephenomenon can be predicted by eigen-analysis as well. This paper usesanalytic methods to integrate the wake dynamics, blade aerodynamics,and nonlinear composite rotor blade flap-lag-torsion structuraldynamics in the form of a coupled system. Only the homogeneousisotropic material blade will be studied in this paper in order tomake a preliminary investigation of a wake-rotor interaction and thecompatibility of the composite blade equation. The Galerkin's methodand the Duncan's polynomial are used to resolve the equations. Thecoupled nonlinear system is separated into equilibrium and disturbant(dynamic) states. The equilibrium state is solved by using nonlinearsolves. The system's flap-lag-torsion eigen-equations are formulatedby the combination of the equilibrium coefficients and the disturbantequations. The Floquet's theory is used to derive the systemeigenvalues. The nonlinear phenomenon will be investigated througheigen-analysis, especially for quasi-linear resonance. Various lagfrequencies (stiffness) of the isotropic rotor blades are studied inthis paper. The equilibrium results show that the wake has strongeffects in the blade tip displacements in higher blade pitch angles.The eigen-analysis of the lag damping shows the eigenvalue veeringphenomenon occurs when pitch angle is 8 degrees. All of these may bedue to the wake effects in the rotor-wake coupled system.
關鍵字 延滯阻尼;非線性輪葉尾流耦合系統;特徵值;共振;襟翼延遲扭轉結構動力學;盤旋;轉子尾流耦合系統;Lag Damping;Nonlinear Blade-Wake Coupled System;Eigenvalue;Resonance;Flap-Lag-Torsion Structural Dynamics;Hover;Rotor-Wake Coupled System
語言 en
收錄於
會議性質 國內
校內研討會地點
研討會時間 20010521~20010523
通訊作者 National Science Council; National Cheng Kung University; National Research Council of Canada
國別 TWN
公開徵稿 Y
出版型式 紙本
出處 Proceedings of The Fourth Pacific International Conference on Aerospace Science and Technology=第四屆太平洋國際航太科技研討會論文集，pp.543-549
相關連結

機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/18449 )

機構典藏連結