Wartsila ?31DF Series Product Manual page 46

3. Technical Data
Notes:
Note 1
Note 2
Note 3
Note 4
Note 5
ME = Engine driving propeller, variable speed
AE = Auxiliary engine driving generator
DE = Diesel-Electric engine driving generator
Subject to revision without notice.
3-22
At ISO 15550 conditions (ambient air temperature 25°C, LT-water 25°C) and 100% load. Flow tolerance 9%.
At ISO 15550 conditions (ambient air temperature 25°C, LT-water 25°C) and 100% load. Flow tolerance 9% and temper-
ature tolerance 10°C in gas mode operation. Flow tolerance 9% and temperature tolerance 15°C in diesel mode operation.
At 100% output and nominal speed. The figures are valid for ambient conditions according to ISO 15550 except for LT-
water temperature, which is corresponding to charge air receiver temperature 55ºC in gas operation and 60 ºC in diesel
mode. With engine driven water and lubricating oil pumps. Tolerance for cooling water heat 10%, tolerance for radiation
heat 20%. Fouling factors and a margin to be taken into account when dimensioning heat exchangers. In arctic option
all charge air coolers are in LT circuit.
Validity of the data in diesel mode operation: at ambient conditions according to ISO 15550. Lower calorific value 42700
kJ/kg. With engine driven pumps (two cooling water + one lubricating oil pump). Tolerance 5%.
Validity of the data in gas fuel operation: total barometric pressure, air temperature and relative humidity according to
ISO 15550:2002(E), LT water temperature corresponding to receiver temperature 55°C, pilot fuel cetane index minimum
50 according to ISO 4264. Lower calorific value 42 700 kJ/kg for pilot fuel and 49 700 kJ/kg for gas fuel. With engine
driven pumps (two cooling water pumps, one lubricating oil pump). Tolerance 5%.
Wärtsilä 31DF Product Guide
DBAE248994