Work, Power and Torque Details about Diesel Marine Aeronautical Engine

Power and Torque

For commercial uses requiring towing, load carrying and other tractive tasks, diesel engines tend to have to better torque characteristics. Diesel engines tend to have their torque peak quite low in their speed range (usually btween 1600 and 2000) rpm for a small-capacity unit, lower for a large engine used in a track).

This provides smoother control over heavy loads when starting from res and crucially, allows the diesel engine to be given higher loads at low speeds than a petrol engine, marking them much more economical for these application. This characteristic is not so desireble in private cars, so most modern diesels used in such vehicles use electronic control,variabe geometry turbochargers and shorter piston stroke to achieve a wide spread of torque over the engine's speed range, typically peaking at around 2500-3000 rpm.

While diesel engines tend to have more torque at lower engine speeds than petrol engines, diesel engines tend to have a narrower power band than petrol engines. Naturally aspirated diesel tend to lack power and torque at the top of their speed range. This narrow band is a reason why a vehicle such as a truck may have a gearbox with as many as 18 or more gears, to allow the engienes power to be used effictive at all speeds. Turbochargers improve the engine's performance equally by flattening the torque curve.