Online Structural Health Monitoring of Rotating Machinery via Ultrasonic Guided Waves

Table 1

Relative amplitudes of L(0,4) and L(0,6) without and with crack when the rotor is at rest.

	Without crack		With crack
	L(0,4)	L(0,6)	L(0,4)	L(0,6)
1	0.207	0.402	0.218	0.438
2	0.212	0.433	0.174	0.372
3	0.195	0.478	0.219	0.531
4	0.234	0.439	0.205	0.369