Theoretical and Experimental Study on the Transient Time-Frequency Characteristics of the Bending-Torsional Coupling Motions of a Rub-Impact Dual-Rotor System

Table 1

Parameters of dual-rotor model.

Physical description	Parameter	Value
Mass	m1, m2, m3, m4, m5, m6, m7 (kg)	2, 10, 2, 2, 6, 2, 8
Radius of the disk	R2, R5 (m)	0.075, 0.03
Initial phase angle of the disk	(rad)	0, 0
Eccentricity of the disk	e2, e5, e7	46.35, 46.35, 47.5
Stiffness of the elastic support	k1, k2, k3, k5 (N/m)	10^6, 10^6, 10^6, 10^6
Length of the shaft segment	l1, l2, l3, l4, l5 (m)	0.33, 0.33, 0.6, 0.23, 0.23
Material properties of the shaft	E, G (Pa)	2 × 10^11, 7.7 × 10^10
Physical properties of the shaft	I, Ip (m^4)	1.178 × 10^−7, 2.356 × 10^−7
Damping of the elastic support	c1, c2, c3, c5 (N^.s/m)	300, 300, 300, 300
Damping of the bending motion	c6, c7, c8, c9, c10 (Ns/m)	150, 150, 150, 150, 150
Damping of the torsional motion	ct1, ct2 (N^.m^.s/rad)	1, 1
Parameters of the rub-impact fault	kr (N/m), ,	8 × 10^6, 1.34 × 10^−4, 0.1
Parameters of the ball bearing	Cb (N/m^3/2),	1.334 × 10^10, 0.005, 40.1, 63.9, 8
Rotating speeds of the rotor system		1500, 2700, 1.8
Parameters of the maneuvering flight	, Rbz (m)	π, 3