Study on Thermal Unstable Vibration of Rotor under Journal Whirl with Large Amplitude in Journal Bearing

Table 4

1X component amplitudes of shaft vibrations at bearings A and B, maximum journal surface temperature difference at bearing A.

Test conditions	1X component amplitudes (μm∠°)				Maximum temperature differences (°C)
	Bearing A		Bearing B
	-Direction	-Direction	-Direction	-Direction
Before dynamic balance	91∠126	53∠355	62∠316	49∠203	4.6
Trial counterweights	Bearing A side: 420 g∠60°, bearing B side: 420 g∠240°
After adding trial counterweights	45∠306	44∠95	45∠121	38∠300	3.5
Balancing counterweights	Remove trial counterweights firstly; then bearing A side: 270 g∠70°, bearing B side: 270 g∠250°
After dynamic balance	20∠42	23∠68	11∠172	18∠259	1.6