- Internal-combustion engine Internal-combustion engine) in
which the heat or pressure energy necessary to produce motion
is developed in the engine cylinder, as by the explosion of a
gas, and not in a separate chamber, as in a steam-engine
boiler. The gas used may be a fixed gas, or one derived from
alcohol, ether, gasoline (petrol), naphtha, oil (petroleum),
etc. There are three main classes: (1) gas engines proper,
using fixed gases, as coal, blast-furnace, or producer gas;
(2) engines using the vapor of a volatile fluid, as the
typical gasoline (petrol) engine; (3) oil engines, using
either an atomized spray or the vapor (produced by heat) of a
comparatively heavy oil, as petroleum or kerosene. In all of
these the gas is mixed with a definite amount of air, the
charge is composed in the cylinder and is then exploded
either by a flame of gas (flame ignition -- now little used),
by a hot tube (tube ignition) or the like, by an electric
spark (electric ignition, the usual method is gasoline
engines, or by the heat of compression, as in the Diesel
engine. Gas and oil engines are chiefly of the stationary
type. Gasoline engines are largely used for automobile
vehicles, boats, etc. Most internal-combustion engines use
the Otto (four-stroke) cycle, though many use the two-stroke
cycle. They are almost universally trunk engines and
single-acting. Because of the intense heat produced by the
frequent explosions, the cylinders must be cooled by a water
jacket (water-cooled) or by air currents (air cooled) to give
the maximum thermodynamic efficiency and to avoid excessive
friction or seizing.
[Webster 1913 Suppl.] internalise internalise v.
Same as internalize. MKChiefly Brit.
The Collaborative International Dictionary of English. 2000.