The dynamic response of a spur gear pair is investigated using a finite ele
ment/contact mechanics model that offers significant advantages for dynamic
gear analyses. The gear pair is analyzed across a wide range of operating
speeds and torques. Comparisons are made to other researchers' published ex
periments that reveal complex non-linear phenomena. The non-linearity sourc
e is contact loss of the meshing teeth, which, in contrast to the prevailin
g understanding, occurs even for large torques despite the use of high-prec
ision gears. A primary feature of the modelling is that dynamic mesh forces
are calculated using a detailed contact analysis at each time step as the
gears roll through the mesh; there is no need to externally specify the exc
itation in the form of time-varying mesh stiffness, static transmission err
or input, or the like. A semi-analytical model near the tooth surface is ma
tched to a finite element solution away from the tooth surface, and the com
putational efficiency that results permits dynamic analysis. Two-single-deg
ree-of-freedom models are also studied. While one gives encouragingly good
results, the other, which appears to have better mesh stiffness modelling,
gives poor comparisons with experiments. The results indicate the sensitivi
ty of such models to the Fourier spectrum of the changing mesh stiffness. (
C) 2000 Academic Press.