Wartsila ?31DF Series, Product Manual

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16.2 Mass moments of inertia
The mass-moments of inertia of the main engines (including flywheel) are typically as follows:
J (kg m
2
) Engine J (kg m
2
) Engine
890 – 990
980 – 1080 14V31
16V31 640 – 740
720 – 820
800 – 900 8V31
10V31
12V31
16.3 Air borne noise
The airborne noise of an engine is measured as sound power level based on ISO 9614-2. The
results represent typical engine A-weighted sound power levels at engine full load and nominal
speed.
W31 Engine A-weighted Sound Power Level in Octave Frequency Band [dB, ref. 1pW] - Diesel Mode
Total 8000 4000 2000 1000 500 250 125 [Hz]
125 114 116 119 121 115 110 100 8V
125 114 118 121 118 115 107 100 10V
W31 Engine A-weighted Sound Power Level in Octave Frequency Band [dB, ref. 1pW] - Gas Mode
Total 8000 4000 2000 1000 500 250 125 [Hz]
120 110 111 112 116 112 111 103 10V
16.4 Exhaust noise
The results represent typical exhaust sound power level emitted from turbocharger outlet to
free field at engine full load and nominal speed.
Exhaust Gas Sound Power Level in Octave Frequency Band [dB, ref. 1pW]
Total 4000 2000 1000 500 250 125 63 32 [Hz]
150 110 113 119 124 129 134 148 146 8V
150 111 115 117 125 131 134 140 149 10V
16-4 DBAE248994
Wärtsilä 31DF Product Guide 16. Vibration and Noise