Examples of Different Engines

An engine is a designed machine that converts various forms of energy into mechanical energy. Engines can function based on fuel combustion or electricity. Some examples of fuel combustion are cars, trains and aeroplanes. Fans, power tools and small appliances are a few examples of electric engines. The different types of engines are differentiated by the type of energy used for their power. They are classified into various groups like thermal engines, electrical engines,and physical engines. Thermal engines may include external and internal combustion engines.

Engine system

An engine system is a place where fuel is converted to mechanical energy. The operation takes place when it has clean air for fuel, water for cooling, electricity for igniting the fuel and oil for lubrication.

Components of the engine system 

• Cylinder block: The main body of the engine where the intake, compression, burning of fuel and guiding of the piston is carried out
• Cylinder head: A removal head containing two ports, one for the intake of fuel and the other for exhaust, where they are closed by inlet and exhaust valves .
• Piston: A prime mover fitted to cylinders to give a tight seal through bore and slide freely inside the cylinder to handle gas pressure generated by the combustion of fuel. 
• Piston rings: Placed to seal and lessen the friction resistance between the piston and cylinder.
• Connecting rods: Connects piston and crankshaft to transmit motion.
• Crankshaft: Receives thrust from piston via connecting rods and converts reciprocating motion to rotary motion.
• Engine bearing: Reduces the friction between moving parts.
• Crankcase: A bearing of the crankshaft where all the oil for lubrication is placed. 
• Spark plug: Ignites the compressed air-fuel mixture in the combustion chamber.

Factors that differentiate engines

The following are some of the factors that differentiate engines from one another.

• Type of fuel used 
• Number of the stroke ignition system 
• Number of the cylinder cycle 
• Operation of cooling system 
• Arrangement of valves and cylinder

Different types of engines

The most influencing factor for the differentiation of engines is the energy source used for motion. The different types of engines include:

• Thermal engines
  • Internal combustion engine (IC)
  • External combustion engine (EC)

• Electrical engines
• Physical engines

Thermal Engines 

Engines that use heat energy as a source for motion either via internal or external combustion are known as thermal energy. It can function either by direct combustion of a propellant or transformation of fluid for combustion. 

Internal combustion engines (IC)

• Internal combustion is an endothermic reaction of fuel that produces high temperatures and pressure inside the combustion chamber. 
• IC engines are further classified into two types—reciprocating engines and rotary engines. The reciprocating engine uses the up and down motion of pistons to convert pressure from gases to rotational motion. Examples include the steam engine and the Stirling engine. The rotary engine uses a rotating triangular rotor to convert heat from the combustion.

External combustion engine (EC)

• External combustion is an exothermic reaction that burns the fuel in one chamber and exhausts the product separately through the heat exchanger.
• The fluid used can either be gaseous or liquid and air mixture.

Electrical engines

Electric engines are generally of three types, namely magnetic, piezoelectric and electrostatic.

Magnetic motor

• It relies on the interaction between a magnetic field and electrical flow to generate work.
• It functions on the principle of the dynamo, but in reverse, to generate electricity.
• The major components of electric motors are a stator—the outer part of the engine that remains immobile and a commutator to shift electrical flow and modulate the induced magnetic field.

Piezoelectric motor

To create work in this motor, a flow of electricity is passed through the materials that have some ultrasonic vibrations.

Electrostatic engines 

They use like-charges to repulse each other and generate rotation in the rotor. Electrostatic engines are not common as magnetic drives as the first use expensive material and the second needs comparatively high voltage to run.

Physical engines

• Physical engines function on stored mechanical energy.
• They are not as efficient as other engines since they cannot reserve a large amount of energy.
• Examples of physical drives include clockwork engines, pneumatic and hydraulic engines.

Conclusion

An engine is a machine designed to convert any form of energy into mechanical energy for motion. The process of conversion of energy requires air, water, electricity and oil. Engines are generally classified into three types, namely thermal engines, electrical and physical engines. Thermal engines are further classified as internal and external combustion engines. Some of the product examples that use the different types of engines include cars, trains, steam engines, small appliances, including watches.