Sm. Barkai et O. Rand, IMPLEMENTATION OF THE HARMONIC VARIABLES CONCEPT IN THE VIBRATION ANALYSIS OF A COUPLED ROTOR FUSELAGE SYSTEM/, Computers & mathematics with applications, 30(9), 1995, pp. 87-104
The paper presents a new numerical technique for deriving and solving
the nonlinear periodic equations of motion of a coupled rotor/fuselage
system. The method is based on the combination of the concept of work
ing with ''Harmonic Variables'' with general purpose nonlinear solvers
. The resulting technique substantially reduces the required analytica
l effort while preserving high accuracy solution and symbolic harmonic
resolution. For demonstration purposes, the present nonlinear modelli
ng consists of elastic blades and fuselage, and contains nonlinear ela
stic and dynamic contributions. The method is demonstrated by a study
of the influence of possible fuselage responsiveness on the vibratory
hub motion and hub loads.