Engine

From WikiMD's Wellness Encyclopedia

Engine is a machine designed to convert one form of energy into mechanical energy. Heat engines, including internal combustion engines and external combustion engines (such as steam engines), burn a fuel to create heat, which then creates a force. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air and others, such as wind-up toys use elastic energy. In biological systems, molecular motors, like myosins, in muscles, use chemical energy to create forces and eventually motion.

Types of Engines[edit | edit source]

There are different types of engines, each with their unique characteristics and uses. Some of the most common types include:

Internal Combustion Engine[edit | edit source]

The Internal Combustion Engine is an engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine, such as pistons or turbine blades or a nozzle, and by moving it over a distance, generates mechanical work.

External Combustion Engine[edit | edit source]

An External Combustion Engine is a heat engine where a working fluid, contained internally, is heated by combustion in an external source, through the engine wall or a heat exchanger. The fluid then, by expanding and acting on the mechanism of the engine, produces motion and usable work. The fluid is then cooled, compressed and reused (closed cycle), or (less commonly) dumped, and cool fluid pulled in (open cycle air engine).

Electric Motor[edit | edit source]

An Electric Motor is an electrical machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a wire winding to generate force in the form of torque applied on the motor's shaft.

Pneumatic Motor[edit | edit source]

A Pneumatic Motor or compressed air engine is a type of motor which does mechanical work by expanding compressed air. Pneumatic motors generally convert the compressed air energy to mechanical work through either linear or rotary motion.

Molecular Motor[edit | edit source]

A Molecular Motor is a natural (biological) or artificial molecular machine that is the essential agent of movement in living organisms. In general terms, a motor is a device that consumes energy in one form and converts it into motion or mechanical work; for example, many protein-based molecular motors harness the chemical free energy released by the hydrolysis of ATP in order to perform mechanical work.

Engine Resources

Contributors: Prab R. Tumpati, MD