Combustion Air System Design - Wartsila ?31DF Series Product Manual

10. Combustion Air System
Under-cooling of the engine room should be avoided during all conditions (service conditions,
slow steaming and in port). Cold draft in the engine room should also be avoided, especially
in areas of frequent maintenance activities. For very cold conditions a pre-heater in the system
should be considered. Suitable media could be thermal oil or water/glycol to avoid the risk
for freezing. If steam is specified as heating medium for the ship, the pre-heater should be in
a secondary circuit.
Fig 10-1
Fig 10-2
10.2

Combustion air system design

Usually, the combustion air is taken from the engine room through a filter on the turbocharger.
This reduces the risk for too low temperatures and contamination of the combustion air. It is
important that the combustion air is free from sea water, dust, fumes, etc.
For the required amount of combustion air, see section Technical data.
The combustion air shall be supplied by separate combustion air fans, with a capacity slightly
higher than the maximum air consumption. The combustion air mass flow stated in technical
10-2
Engine room ventilation, turbocharger with air filter (DAAF391752)
Engine room ventilation, air duct connected to the turbocharger
(DAAF391711)
Wärtsilä 31DF Product Guide
DBAE248994