History and Engineering of the Diesel Engine

Rudolf Diesel
Rudolf Diesel



The Diesel Engine has been around for a very long time. And there is no reason to believe that it will go away anytime soon. The diesel engine was named after Rudolf Diesel, the man that invented it.


Rudolf was a German Engineer. He spent his childhood in France. Circumstances like the Franco-German War eventually compelled him to travel to England. Though, his determination to expand his understanding of engine design eventually drew him back to Germany.

Rudolf started working on the diesel engine at a time when trains were driven by steam. While they had their merits, steam engines were expensive. They relied heavily on coal and their design had several inefficiencies.

Larger corporations didn’t care because they had the financial means to meet the cost of maintaining steam engines. But small and medium-sized entities were not as lucky. Their budgetary constraints prevented them from making effective use of steam engineering.

This is where Rudolf entered the picture. He realized that a small internal combustion engine that could convert heat into work could easily exceed the power of a steam engine. After studying thermodynamics, Rudolf started working to make his idea a reality.

His internal combustion engine was a hit in the 19th Century, finding a market among owners of horse-drawn carriages and anyone that used steam-powered engines. Rudolf’s success wasn’t instant and it did not last long.

He spent many years tinkering with various designs. At one point, he toyed with the notion of creating a solar-powered engine. He also hoped to create an internal combustion engine capable of turning 75 percent of heat into energy. He failed. The final product was only 25 percent effective.

Though, that still made his engine considerably superior to his rivals. Rudolf’s products were a mixed bag. While his engines were highly efficient for their time, they were also unreliable and many of his customers eventually returned them.

Rudolf Diesel's Engine
Rudolf Diesel’s Engine 1894

Their demands for refunds brought the engineer to the very edge of ruin. He had better luck with the military, with the French eventually adding his engines to their submarines in 1904. That wasn’t enough to save Rudolf from his financial woes, which is why some people believe that he jumped to his death in 1913.

Official records state that he went overboard during a trip across the English Channel. He was supposed to meet British navy officials to discuss the possibility of introducing his engines to their submarines. It has been theorized that he was thrown overboard. Some people believe that certain petroleum companies were threatened by his work.

It has also been suggested that coal magnates thought that his engine would make their industry irrelevant. If conspiracy theorists are to be believed, the Germans wanted to stop him from revealing the designs of their new U-Boats to the British.

Whether he accidentally fell overboard, committed suicide, or was murdered by his enemies, no one knows for sure. Ultimately, his engine found success. At first, armies around the world started using it for all their vehicles and vessels.

Then it became commonplace in civilian cars and factories. It is still present today in most parts of the world. People use it to operate all kinds of machinery.


If you’ve never seen a diesel engine in action, this is what you should know:

1). Before diesel engines were invented, trains relied on steam engines that utilized external combustion mechanisms. Coal was added to a boiler. This produced fire. The heat turned the water to steam. The steam was transmitted to a piston which it moved back and forth. In doing so, the steam got the wheels of a train to move.

2). A diesel engine is called an internal combustion engine because the fire is inside rather than outside. They were immediately recognized as the superior option because they did not waste any energy.

diesel engine
Diesel Engine of Today

In a steam engine, the heat had to travel from one part of the system to another to play its role, permitting energy loss and wastage to occur. But in a diesel engine, the heat played its role in the same place that it was created. This made for a more efficient system.

3). The diesel engine works by drawing air into the cylinder where it is compressed one or two dozen times by the piston. These compressions generate a lot of heat The gasses normally reach a minimum of 500 degrees centigrade.

At this point, a fuel injection system sprays a mist of fuel into the cylinder. The high temperature of the air causes the fuel to ignite immediately. The result is a controlled explosion that forces the piston out of the cylinder.

This generates the immense power that is required to make a vehicle or machine operate. The amount of fuel sprayed will depend on the amount of power the driver or machine operator needs.

4). The Piston doesn’t stay outside the cylinder. Rather, it slips back into the cylinder once more as the exhaust gasses escape through the exhaust valve. That is the end of the process. After this, everything starts again. That procedure sounds slow but a diesel engine goes through this cycle thousands of times every minute.

5). Diesel and gasoline engines are not the same, though their operations are somewhat similar. A gasoline engine also features metal cylinders. A mixture of air and fuel is drawn into the cylinders. The piston compresses the mixture before a sparking plug sets it ablaze with an electric spark, producing an explosion that forces the piston out of the cylinder, moving the wheels.

As you can see, a gasoline engine uses sparking plugs to create an explosion. A diesel engine doesn’t. The gasoline engine doesn’t compress the mixture as thoroughly as its diesel counterpart.

Diesel machines and diesel performance parts and vehicles are typically more efficient because of their engines. They can do more work using the same fuel as a gasoline engine because they compress their fuel-air mixtures more. This produces higher temperatures and more energy.

The absence of spark plugs is also beneficial because it allows engineers to use a simpler design to produce more energy by burning the fuel at higher temperatures.