Abstract：Face-gear drives have great potential in the aviation and automotive industries. However, torsional vibrations are a key issue in face-gear pairs. This study focuses on modeling and analyses of the torsional vibrations in a face-gear pair. A torsional vibration model is given for a one-input, one-output face-gear drive with asymmetric time-varying mesh stiffness, backlash nonlinearity and static transmission errors. The torsional mesh stiffness of a face-gear pair is calculated from a loaded tooth contact analysis in a numerical example. The torsional vibration model is validated by comparing the responses with the dynamic responses predicted by Abaqus. The model is then used to analyze the dynamic behavior of a face-gear pair for the design conditions to investigate the effects of mesh stiffness, backlash, static transmission errors, and torque fluctuations on the dynamic characteristics of the face-gear pair and the nonlinear dynamic response. The results show that the model accurately predicts the face-gear pair torsional vibrations and can be used to study the mesh characteristics and the dynamic characteristics of face-gear pairs to guide the design of face-gear pairs.
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