Dynamic Analysis Of Helicopter Rotor Blade

Rotor dynamics is one of the kennels in helicopter flight. The vibration of helicopter is associated with speed. When speed is high, vibration is mostly the reasons that limit the speed and reduce the efficiency of engine. So far, why helicopter's R&D behind plane, is mainly due to the low understanding of airflow in rotor blade. Because of the complicated rotor, even assume the blade a rigid body; it contains flap, lag and torsion. All the motions coupled together, formed a complex structure—dynamics problem. The simulation of rotor blade is always the forward area in helicopter R&D.Recently, the dynamics of flexible multibldy systems is taking more and more attention, one of its foundations is the coordinate transformation that rotating fixed axis. However, there is plenty of moving axis in reality, the coordinate transformation that rotating moving axis is always the difficulty in space dynamics of flexible multibody systems.This paper is based on dynamics of flexible multibody systems, from fixed axis mass matrix of flexible multibody system in three dimensions, deduced the moving axis mass matrix of flexible multibody in three dimensions. After this, using moving axis mass matrix, established the dynamic control equation of flexible rotor blade, solving with iteration default revise method, we can gain the dynamic respond when helicopter halting in two dimension air model. Numerical calculation and theoretical analyses indicate that this model and dynamical control equation are correct and reasonable.