Comprehensive analysis of bearingless rotors - Model development and experimental correlation of modes, response, trim and stabilityA generic mathematical model that is capable of accurately modeling the multiple load path bearingless rotor blade is developed. A comprehensive, finite element based solution for the natural vibration of the rotor blade is developed. An iterative scheme based on harmonic balance is used to evaluate the nonlinear response of the rotor to control inputs and a Newton-Raphson procedure is employed to evaluate the trim of rotorcraft. Linearized perturbation model of the nonlinear system are presented. The model is validated by comparing with existing whirl tower, wind tunnel and flight test results of BMR/BO-105 helicopter. Frequencies of two bearingless rotor blades compare well with results from experiments. Nonlinear response and trim results are presented for the bearingless BMR/BO-105 rotor. Aeroelastic stability in forward flight, evaluated using floquet theory agrees with test data in general.
Document ID
19930040744
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Jambunathan, V. (NASA Langley Research Center Hampton, VA, United States)
Murthy, V. R. (Syracuse Univ. NY, United States)
Date Acquired
August 16, 2013
Publication Date
January 1, 1993
Subject Category
Aircraft Design, Testing And Performance
Report/Patent Number
AIAA PAPER 93-0624
Meeting Information
Meeting: AIAA, Aerospace Sciences Meeting and Exhibit