Napier Deltic facts for kids

Animation of a Deltic engine

The Napier Deltic is a special kind of diesel engine. It was used in boats and railway locomotives. This engine is unique because its cylinders are shaped like a triangle. Inside each cylinder, there are two pistons. It also has three crankshafts that work together. Most Deltic engines had either nine or eighteen cylinders. These powerful engines were built by a company called D. Napier & Son.

What Makes the Deltic Engine Special?

The Napier Deltic engine has a very unusual design. Instead of cylinders in a straight line or a 'V' shape, they are arranged in a triangle. Imagine three rows of cylinders forming a triangle. Each of these cylinders has two pistons that move towards each other. This design helps the engine be very powerful for its size.

How Does the Deltic Engine Work?

In a normal engine, one piston moves up and down in a cylinder. But in the Deltic, two pistons move in each cylinder. They move towards each other to squeeze the fuel and air. When the fuel burns, it pushes the pistons apart. This movement turns three main shafts called crankshafts. These crankshafts are connected by gears, which send power out from the engine.

The animation shows how it works:

• Green shows air coming into the engine.
• Orange shows the fuel and air burning.
• Purple shows the used exhaust gas leaving.

Where Were Deltic Engines Used?

Deltic engines were known for being very strong and reliable. They were used in two main places:

• Boats: Many fast patrol boats and mine countermeasures vessels used Deltic engines. Their compact size and high power were perfect for naval ships.
• Trains: In the United Kingdom, some very famous trains called "Deltics" used these engines. These trains were known for being fast and powerful, pulling passenger coaches across the country.

Who Built the Deltic Engine?

The Napier Deltic engine was designed and built by a British company called D. Napier & Son. They were known for making advanced engines. The first Deltic engine was developed in the late 1940s. It was a big step forward in engine design at the time.

Images for kids

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  Animated diagram of Deltic engine

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  Cylinder firing order of the 18 cylinder Napier Deltic diesel engine: The grid represents triangular cylinder arrangement (banks A, B, C) and rows 1 to 6

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  The Deltic-powered Hunt-class mine countermeasures vessel HMS Ledbury

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  Napier Deltic powered British Rail Class 55 D9009 Alycidon, at the National Railway Museum, York, UK

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  Napier Deltic engine at the National Railway Museum, York, UK

See also

In Spanish: Napier Deltic para niños