WÄRTSILÄ 46DF, Product Manual

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1.2 Output limitations in gas mode
1.2.1 Output limitations due to methane number
Fig 1-1 Output limitations due to methane number
Calculation Formulas for different compression ratios
if MN ≥ 80 and tbax ≤ 45 → KKNOCK = 1 CR 12.7:1
if MN < 80 and/or tbax > 45
→
KKNOCK = 1 -
0.017*(80 - MN) - (1 - (1 + 0.01*(45 - tbax)))
NOTE
In case of MN <80 and MN >70 derating factor could be 1%/1MN with a
penalization of efficiency.
1-2 DBAD209883
Wärtsilä 46DF Product Guide 1. Main Data and Outputs