Nonlinear Torsional Dynamics of Star Gearing Transmission System of GTF Gearbox

Table 1

GTF gearbox system parameters.

Parameters	Sun gear	Star gear	Ring gear
Number of teeth	43	42	127
Helical tooth width (mm)		60
Normal modulus (mm)		3.5
Normal pressure angle (degree)		22.5
Helix angle (degree)		27
	External meshing pair		External meshing pair
Average meshing stiffness ()	3.025 ×		3.400 ×
Varying meshing stiffness ()	1.679 ×		2.111 ×
Damping ratio of meshing pair stiffness	0.02		0.02