
9 Forced induction
9.1 NATURAL ASPIRATION AND FORCED
INDUCTION
General considerations
Both petrol and diesel engines for motor vehicles may
be further classified according to the manner in which
their induction process is accomplished, namely natural
aspiration or forced induction.
Natural aspiration
So far consideration has been given only to those
engines that fall into this particular classification, be-
cause their induction process relies solely on the press-
ure difference that exists between the retreating piston
and the air intake arrangements. The density of charge
that ultimately fills the cylinder owing to the pumping
action and velocit ...