When it comes to diesel engines, there’s a fair bit of misinformation that can confuse you. Although it is still an internal combustion engine, diesel technology is very different from the traditional gas engine. If you are wondering how diesel engines work, this guide can help you understand the fundamentals.
The internal combustion engine has been around a very long time. Combustion engines have one job; that is to transform the chemical energy and fuel and transform it into mechanical energy. This is traditionally done in a gas engine through fuel injection and spark plugs.
For an article on the traditional four-stroke engine cycle, check our guide here.
Inside Diesel Engines
Now while the way in which the fuel mixture is ignited may be different in diesel engines, but its job is still the same. By creating the mechanical power created through combustion of the chemical energy, the crankshaft is then turned.
Diesel engines have served mankind for well over a century now. They are some of the most economical and reliable forms of
Diesel engines are all about producing high temperature and high pressure. It is through this high-pressure environment, where the air-fuel mixture is combusted.
The piston and rods shown above in the Cummins diesel engine are contained in is known as a slider crank mechanism. This is a linear motion mechanism that primarily moves up and down. This up and down movement is the basics of the four stroke cycle.
Diesel engines combust the diesel fuel, forcing the piston downward. As the diesel piston moves downward, the intake valves are opened. This is known as the intake cycle.
During the return stroke in a diesel engine, the exhaust valves are closed and the air inside the cylinder gets compressed during the compression stroke.
As the piston compresses this air, atomized diesel fuel is added to the combustion chamber. When the temperature and pressure of the air rises above the self-ignition value of the diesel mixture, combustion occurs. This spontaneous explosion as a result of the pressure and temperature rise forces the engine piston downwards.
This is the basic fundamental concept of the four-stroke engine cycle. While diesel engines accomplish this feat far differently than their gas counterparts, it’s still the same job.
If you have ever seen a diesel engine piston, you may have noticed that a bowl is provided on top of the piston itself. This bowl is designed to help promote internal combustion chamber turbulence. This turbulence during the downstroke helps to atomize the fuel mixture, increasing thermal efficiency.
What do you think about our diesel engines FAQ guide? Want to learn more about the Powerstroke or Cummins engines? Check out one of our sister sites, Wasatch Diesel Performance here, and subscribe to My Pro Street for all the latest and greatest automotive news, DIY guides and articles.
