16. Vibration and Noise
Wärtsilä 34DF generating sets comply with vibration levels according to ISO 8528-9. Main engines comply
with vibration levels according to ISO 10816-6 Class 5.
16.1 External forces and couples
Some cylinder configurations produce external forces and couples. These are listed in the tables below.
The ship designer should avoid natural frequencies of decks, bulkheads and superstructures close to the
excitation frequencies. The double bottom should be stiff enough to avoid resonances especially with the
rolling frequencies.
Figure 16.1
Coordinate system
Table 16.1 External forces and couples
F
Z
[kN]
F
Y
[kN]
Frequency
[Hz]
M
Z
[kNm]
M
Y
[kNm]
Frequency
[Hz]
M
Z
[kNm]
M
Y
[kNm]
Frequency
[Hz]
Speed
[rpm]
Engine
–
–
–
–
–
–
–
–
24
26
24
25
41
45
41
45
12
12.5
720
750
W 9L34DF
–
0.1
–
–
–
75
–
–
–
–
–
–
–
–
–
–
–
–
720
750
W 12V34DF
3
3
4
4
48
50
–
–
–
–
–
–
–
–
–
–
–
–
720
750
W 16V34DF
– couples are zero or insignificant.
142
Product Guide Wärtsilä 34DF - 3/2012
Product Guide
16. Vibration and Noise
