Forklift Engine - Likewise called a motor, the engine is a device which could convert energy into a useful mechanical motion. Whenever a motor changes heat energy into motion it is usually known as an engine. The engine could be available in several types like for example the external and internal combustion engine. An internal combustion engine typically burns a fuel with air and the resulting hot gases are used for generating power. Steam engines are an example of external combustion engines. They utilize heat to generate motion along with a separate working fluid.  
The electric motor takes electrical energy and generates mechanical motion through different electromagnetic fields. This is a typical kind of motor. Several types of motors function by non-combustive chemical reactions, other types could make use of springs and be driven through elastic energy. Pneumatic motors are driven through compressed air. There are various designs based on the application required.
Internal combustion engines or ICEs 
Internal combustion occurs whenever the combustion of the fuel mixes together with an oxidizer in the combustion chamber. In the IC engine, higher temperatures will result in direct force to certain engine parts like for instance the nozzles, pistons, or turbine blades. This force produces functional mechanical energy by moving the component over a distance. Usually, an ICE has intermittent combustion as seen in the popular 2- and 4-stroke piston motors and the Wankel rotating engine. The majority of jet engines, gas turbines and rocket engines fall into a second class of internal combustion motors known as continuous combustion, that takes place on the same previous principal described.
External combustion engines like for example steam or Sterling engines differ significantly from internal combustion engines. External combustion engines, where the energy is delivered to a working fluid such as pressurized water, liquid sodium and hot water or air that are heated in some type of boiler. The working fluid is not mixed with, comprising or contaminated by combustion products.
A range of designs of ICEs have been created and placed on the market together with numerous strengths and weaknesses. When powered by an energy dense fuel, the internal combustion engine provides an effective power-to-weight ratio. Even if ICEs have succeeded in several stationary applications, their actual strength lies in mobile utilization. Internal combustion engines control the power supply intended for vehicles like for instance cars, boats and aircrafts. A few hand-held power tools use either ICE or battery power gadgets. 
External combustion engines 
An external combustion engine is comprised of a heat engine wherein a working fluid, such as steam in steam engine or gas in a Stirling engine, is heated through combustion of an external source. This combustion occurs via a heat exchanger or via the engine wall. The fluid expands and acts upon the engine mechanism which generates motion. Afterwards, the fluid is cooled, and either compressed and reused or discarded, and cool fluid is pulled in. 
The act of burning fuel along with an oxidizer in order to supply heat is known as "combustion." External thermal engines could be of similar use and configuration but utilize a heat supply from sources like for example exothermic, geothermal, solar or nuclear reactions not involving combustion. 
The working fluid can be of whichever constitution. Gas is the most common kind of working fluid, yet single-phase liquid is occasionally used. In Organic Rankine Cycle or in the case of the steam engine, the working fluid adjusts phases between gas and liquid. 	
                            
                                                            
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