Volvo IPS650, Руководство по установке

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Engine Room Ventilation
Engine performance
Diesel engines require a surplus of air. Deviations from
normal values first present themselves as more black
smoke than usual. This may be especially noticeable
at the planing threshold when the engine must deliver
the highest possible torque.
If deviations from normal values are great, the diesel
engine will lose power. The power loss may be so great
that a planing boat is unable to overcome the planing
threshold.
In order for the engine to function properly and provide
full power, it is absolutely essential that both inlet and
outlet air ducts are dimensioned and installed cor-
rectly.
Two principle conditions must be met:
A The engine must receive sufficient air (oxygen) for
fuel combustion.
B The engine compartment must be ventilated such
that the temperature can be kept at an acceptably
low level.
Ventilation is also important to keep the temperature
of engine electrical and fuel systems low, and to guar-
antee normal engine cooling.
Ventilation must also be suitably adapted if crew mem-
bers will be present in the engine compartment.
NOTICE! Current national safety regulations and leg-
islation must be followed. Each classification society
has its own rules that must be followed as required.
Engine power at high altitudes above sea level
In most cases marine engines are used at, or close to,
sea level. However, there are lakes at high altitudes
above sea level.
Operations at high altitudes involve a power loss owing
to a drop in air density (and thereby oxygen levels) as
altitude increases. This will result in the development
of smoke and the turbocharger running at abnormally
high rpm with increased wear.
However, power loss is not significant below approx.
500 m (1640 ft) above sea level. At altitudes in excess
of 500 m (1640 ft) above sea level, power loss is
around 0.1% per 100 m (328 ft).
Volvo Penta IPS 650, 800 and 950 engines are not
suitable for operations above 1,500 m (5,000 ft).
Arrangement and Planning, Engine Room
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