Understanding the applications of diesel engine

Applications of the diesel engine on vehicles and industrial generators have increasingly high over the years. However, the gasoline (petrol) engine can somehow serve some purposes of this so-called diesel engine of higher cost.

Let me remember you, diesel engines vary from gasoline engines from their combustion process to the efficiencies they offers. In a diesel engine, air and fuel are infused in different stages and it compresses just the air at a higher ratio. A diesel engine compresses at the ratio of 14:1 up to 25:1, whereas in a gasoline engine the compression ratio is between 8:1 and 12: The very high temperature in the engine, much higher than the temperature attained in a gasoline engine. At peak temperature and pressure, diesel that is let into the engine ignites on account of the extreme temperature.

Our purpose here today is to examine generally the applications of diesel engines leading to their advantages. Previously, an article was published on Diesel engine check out!

Read more: Understanding Diesel engine efficiency


Applications of diesel engine

The followings stated below are areas where diesel engines are used. However, the characteristics of diesel have different advantages for different applications.

Read more: Difference between SI (Spark ignition) and CI (Compression ignition) engines

Passenger Cars:

Diesel is quite known for larger trucks, bigger cars, and now smaller bigger cars like the superminis. Smooth operation, as well as high low-end torque, are deemed important for passenger cars and small commercial vehicles. The use of electronically controlled fuel injection has improved the smooth torque generation, making the manufacturer produce high-end luxury vehicles with diesel engines. Passenger car diesel engines usually have between three and ten cylinders, and a displacement ranging from 0.8 to 5.0 litres. Modern powerplants are usually turbocharged and have direct injection.


Diesel locomotives appeared first in 1913, built for continuous operation and may require the ability to use poor quality fuel in some situations. Some locomotives use a two-stroke diesel engine, but many modern diesel locomotives are designed diesel-electric locomotives; the diesel engine is used to power an electric generator that in turn powers electric traction motors with no mechanical connection between diesel engine and traction. Diesel engines have eclipsed steam engines as the prime mover on all non-electrified railroads in the industrialized world.

Read more: Difference between petrol and diesel engine


The requirements for marine diesel engine varies, based on their application. mass usage of the diesel engine in the military and medium-size boats are suitable on medium-speed four-stroke diesel engines. These engines usually contain up to 24cylinders and have power outputs in the one-digit Megawatt region. Diesel engines for lorry may be used on small boats. while, large ships use extremely efficient, low-speed two-stroke diesel engines. They can reach efficiencies of up to 55%. Unlike most regular diesel engines, two-stroke watercraft engines use highly viscous fuel oil. Submarines are usually diesel-electric.

Stationary diesel engine:

Stationary diesel engines are commonly used for electricity generation, but also for powering refrigerator compressors, or other types of compressors or pumps. Usually, these engines run permanently, either with mostly partial load or intermittently, with a full load. Stationary diesel engines powering electric generators that put out alternating current, usually operate with an alternating load but fixed rotational frequency. This is due to the mains’ fixed frequency of either 50 Hz (Europe), or 60 Hz (United States). The engine’s crankshaft rotational frequency is chosen so that the mains’ frequency is a multiple of it. For practical reasons, this results in crankshaft rotational frequencies of either 25 Hz (1500 per minute) or 30 Hz (1800 per minute).

Read more: Understanding petrol engine

Stationary diesel engine

Non-road diesel engine:

The applications of non-road diesel engine are common for construction equipment. It offers better usability such as fuel efficiency, reliability, and eases of maintenance. however, high power output and quiet operation are negligible. Therefore, mechanically controlled fuel injection and air-cooling are still very common. The common power outputs of non-road diesel engines vary a lot, with the smallest units starting at 3 kW, and the most powerful engines being heavy-duty lorry engines.

Read more: Four-stroke engine: everything you need to know


The applications of diesel engines in aircraft have existed before world war ll. However, in the late 1970s, there has not been any applications of the diesel engine in aircraft. In 1978, Karl H. Bergey suggests that “the likelihood of a general aviation diesel in the near future is remote.” In recent years (2016), diesel engines have found use in unmanned aircraft (UAV), due to their reliability, durability, and low fuel consumption. finally, In early 2019, AOPA reported, that a diesel engine model for general aviation aircraft is “approaching  the finish line.”

Aviation engine

Read more: Two-stroke engine: everything you need to know

That is all for this article, where the applications of diesel engine. I hope you got enough from the reading, if so, kindly share with other students. Thanks for reading, see you next time!

Join our Newsletter

Write A Comment