What is an Engine?

An engine is a device which turns physical input into kinetic energy. This means that something goes into the engine, and the engine makes energy out of it. This doesn’t mean that anything can go in; on the contrary, there are certain types of engines that do different things with different inputs.

I’m not talking about engines in the way you may be thinking… Just because you type into a search box and it provides an output, doesn’t make a search engine an engine.

No, I’m talking about engines that do ‘work’. This work is generally created through the exertion of torque by an engine. Torque is force in a circle, or spinning force. The higher the engine torque, the faster the vehicle goes! There are other methods used by engines to do work, however. ECEs can simply burn fuel to create thrust, see below.

The engines that this website will cover are described below. There are two main types of engines; Internal Combustion Engines (ICEs), and External Combustion Engines (ECEs). As their names suggest, one transfers the input into the output inside the engine, the other transfers the input into the output via an outside source. This is all explained below.

External Combustion Engines

An External Combustion Engine, or ECE, is a machine that creates torque or thrust by burning fuel.

Most ECEs change fuel outside the engine which transfers energy somehow into the engine. An example of this is is the steam engine. Water is heated outside of the engine, spinning the turbine (the actual part that is called the engine).

The rocket engine is also an ECE, in that fuel is burned outside the rocket (which, unconventionally, is still an engine).

Image via Wikipedia

Internal Combustion Engines

An Internal Combustion Engine, or ICE, is also a machine that creates torque or thrust by burning fuel. These engines transfer energy from one form to another completely within the engine, as can be seen from the flash module I created below and to the right. This flash animation is one demonstrating a single piston out of a 4 stroke engine, which are common in most vehicles driven today. Fuel is mixed with air, compressed and explodes all within the engine. This makes the flywheel spin, creating torque.

Internal Combustion engines are the most common today, and are present in most vehicles today. These engines are not perfect, and still create exhaust. This exhaust is a by-product of the fuel mixture and the reaction caused by the engine. There are three main types of ICEs. There is the V engine, commonly seen in vehicles under the title “V6″ or “V8″, which simply means that the pistons are arranged in a V shape. There is the inline engine, which means all pistons are in one line, and finally the boxer engine, where pistons horizontally oppose each other.

Image via Wikipedia