Frequency analysis on rotating shaft

Objective-

To perform frequency analysis on rotating shaft. To determine the mode shapes and resonant frequencies of the model.

Introduction-

Frequency analysis is carried out to determine the natural frequencies of a part. If multiple parts in a machine have the same frequency the displacement due to the natural frequency will get amplified due to resonance.

Model Specifications-

Bearing steps: Radius: 10mm, Length: 15mm (figure 1)

Shaft: Radius: 15mm, Length: 450mm on both sides of the disk. (figure 1)

Disk: Radius: 60mm, Length: 30mm (figure 1)

Figure 1: Model specifications

Figure 2: Model Represtation

Boundary Conditions-

Material- Alloy Steel (figure 3)

Figure 3: Material Properties

Mesh Size- 2mm (figure 4)

Figure 4: Mesh parameters

Fixtures Applied- Stepped surfaces at the ends (figure 5)

Figure 5: Fixture representation

Results:

Mode Shapes:

The mode shapes of the model are shown below. (Figures 6 to 10)

Figure 6: Mode shape 1

Figure 7: Mode shape 2

Figure 8: Mode shape 3

Figure 9: Mode shape 4

Figure 10: Mode shape 5

Resonant frequencies:

The resonant frequencies of the model are(in hertz): (Figure 11)

1. 105.64
2. 105.69
3. 382.88
4. 407.08
5. 407.25

Figure 11: Resonant frequency table.