Volvo D11 series, Руководство по установке

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Engine room, ventilation and soundproofing
Introduction
Engine performance
Engine power is affected by a number of different
factors. Among the most important ones are air pres-
sure, air temperature and exhaust backpressure.
Deviations from the normal values affect engine per-
formance and function.
Diesel engines require excess air. Deviations from
the normal values show up first of all with an increase
in black smoke. This can be particularly noticeable at
the planing threshold when the engine must give its
greatest possible torque.
If the deviations from the normal values are great, the
diesel engine will lose power. This power loss can be
so great that a planing boat cannot pass through the
planing threshold.
For the engine to function properly and give full
power, it is absolutely necessary that both the inlet
and outlet air ducts are sufficiently dimensioned and
installed correctly.
Two main conditions must be fulfilled:
A. The engine must get enough air (oxygen) to allow
for the combustion of the fuel.
B. The engine room must be ventilated, so that the
temperature can be kept down to an acceptable
level.
Ventilation is also important to keep the engine’s
electrical equipment and fuel system at a low tem-
perature, and for certain general cooling of the en-
gine.
If personnel are to be present in the engine room, the
ventilation installation must be adapted accordingly.
NOTE! All valid safety regulations and legal require-
ments for each country must be followed. Each clas-
sification society has its own regulations that must be
followed when required.