a compression-ignition engine in which a spray of fuel, introduced into air compressed to a temperature of approximately 1000° F (538° C), ignites at a virtually constant pressure.
When the locomotive is traveling at a constant speed or idling, the battery rather than the diesel engine can power the motor.
Trains use a diesel engine to run either a generator or an alternator.
It may get a diesel engine to boost fuel economy significantly.
More impressively, a diesel engine is more efficient, but it also costs more to produce.
It is a hybrid, and the diesel engine is supplemented by an electric motor.
British Dictionary definitions for diesel engine
diesel engine
noun
1.
a type of internal-combustion engine in which atomized fuel oil is sprayed into the cylinder and ignited by compression alone
diesel engine in Science
diesel engine
(dē'zəl)
An internal-combustion engine in which the fuel oil is ignited by the heat of air that has been highly compressed in the cylinder, rather than by a spark. Due to the need for the engine to withstand very high pressures, diesel engines are relatively heavy; however, they are relatively fuel-efficient, especially when running at low power.