Marine Installation Manual
2021-08
4-93
4 Ancillary Systems
4.10 Engine room ventilation
X72DF
4.10
Engine room ventilation
Special attention for the engine room ventilation is essential to ensure
trouble-free operation of all equipment. It is important that the ventilation re
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quirements, ventilation arrangement, air quality and outside ambient air temper
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ature are taken into consideration.
4.10.1
Ventilation requirements
Engine room ventilation is to conform to the requirements specified by the legis
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lative council of the vessel’s country of registration and the classification society
selected by the ship owner.
Calculation methods for combustion air flow requirements and for avoiding ex
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cessive heating of the machinery spaces are provided in the international
standard ISO 8861 ‘Shipbuilding — Engine-room ventilation in diesel-engined
ships — Design requirements and basis of calculations’.
The engine’s combustion air is considered, and typically provided, as part of the
overall engine room ventilation system. Approximately 50 % of the overall en
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gine room ventilation air is for the main engine’s combustion, while the other
half is used for the auxiliary engines, the boilers, and to provide sufficient cooling
for equipment in the engine room. It is therefore vitally important that the venti
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lation system for the engine room has sufficient capacity to supply the necessary
air flow for all engine room needs.
The heat emissions, required air flow and estimated power for the layout of en
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gine room ventilation can be obtained from the
application. These values
consider the ISO 8861 standard, however, in some circumstances the results are
different from the standard calculations. In these cases, WinGD has provided the
specific engine values and these should be considered before ISO 8861.
It should be noted that the engine requires less combustion air when not running
at full load. This then provides potential energy savings by reducing the fre
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quency of the ventilation fans when demand is low. This process can be auto
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mated, interfacing with the engine, if requested.
