Abstract:
High-speed right-angle geared rotor systems are widely used in automotive and
rotorcraft transmission applications. Hypoid gear pairs are one of the commonly applied
right-angle geared systems. They are designed to transmit significant amount of rotational
power between two perpendicular, non-intersecting shafts. However, this class of geared
rotor systems is often plagued by excessive vibration and noise problems. In most cases,
the gear whine generated leads to costly warranty issues. This thesis work is focused on
the dynamic response analysis of a generic hypoid gear pair. A unique non-linear timevarying
dynamic model of the hypoid gear pair system is proposed which includes
backlash non-linearity, linear time-varying gear meshing stiffness, time-varying mesh
characteristic vectors as well as sliding friction effects. The model is applied to study the
physical phenomenon governing the generation of dynamic mesh force that is believed to
be the main cause of high vibration and noise levels. Solutions are presented in the forms
of semi-analytical and numerical integration results. Parametric studies reveal new,
previously unstudied findings of the controlling factors and vibratory behaviors under
light, medium, and high mean loads. Using the numerical simulation, critical non-linear
behaviors in system response such as the jump phenomenon, impact regimes, subharmonic,
and chaotic resonance are investigated. Classification of the steady-state
solutions is presented based on the results of time histories, phase plane plots, Poincare
maps, and Fourier spectra.
