Online Structural Health Monitoring of Rotating Machinery via Ultrasonic Guided Waves

Table 2

Relative amplitudes of L(0,4) and L(0,6) without and with crack when the rotor rotates at 15Hz.

	Without crack		With crack
	L(0,4)	L(0,6)	L(0,4)	L(0,6)
1	0.207	0.429	0.204	0.407
2	0.198	0.408	0.137	0.308
3	0.151	0.330	0.229	0.467
4	0.169	0.243	0.163	0.251