There are multiple engine types and the major ones are classified according to the type of fuel, arrangement of cylinders and air intake.
According to type of fuel –
Working of petrol and diesel engines can be understood from – https://www.youtube.com/watch?v=bZUoLo5t7kg
Electric Engine – Designed to run on electric charge stored onboard battery. The most common electric vehicle in India – is the e-rickshaw. They have lesser environmental impact than conventional vehicles with no tail pipe emissions, cheaper to operate, low maintenance and also, reduced noise pollution
Electric engines are of various types. They may use only electric energy known as Electric Vehicle (EV), using only electrical energy stored in a rechargeable high-density battery for propulsion. Example – Tesla Model S
On the other hand, Hybrid Electric Vehicle (HEV) combines two power sources of an internal combustion engine and an electric motor. Example – Diesel Electric or Petrol Electric. Example – Toyota Camry Hybrid, Honda Civic Hybrid
As the technology has advanced Fuel Cell Electric Vehicles have been introduced. It stores compressed hydrogen under high pressure in tanks and produces its own electricity for power with zero exhaust emissions. The technology is still under testing and you might see this near future.
Engine types according to arrangement of cylinders
In-line – In-line engines have the cylinders arranged, one after the other, in a straight line. Almost all four cylinder engines are straight/inline engine. They are small, compact and involves a lower cost of manufacturing.
V type – The V-type engine has two rows of cylinders set normally at a ninety-degree angle to each other. Advantages include its short length, higher rigidity of the block, its heavy crankshaft, and attractive low profile. V-type can be used for both front wheel drive and rear wheel drive They allow for greater displacements and potential of more cylinders in lesser space.
Horizontally opposed/ flat – The boxer is an engine design that features 2 banks of cylinders with 180 degrees of separation between the two with a single crankshaft. These types are rather smooth and provide low centre of gravity
Rotary/Wenkley – Internal-combustion engine in which the crankshaft remained stationary and the entire cylinder block rotated around it. The only production car to still have a Rotary/ Wankel engine design in production today is the Mazda RX-8 and previous RX-7 models.
Engine types according to air intake –
Naturally Aspirated – Naturally aspirated engines draw air into the engine through an air intake, which depends on creating a vacuum to feed air into the engine’s intake manifold. NA engines have linear Power delivery and are cheaper to own.
Turbocharged – Turbochargers draw some of the gases from the car’s exhaust manifold, forcing them back around into the engine’s intake manifold to pack more air into the cylinders and create a more power. They are more fuel efficient and churn out more power and torque
Supercharged – A supercharger is an air compressor that increases the pressure or density of air supplied to an internal combustion engine. This gives each intake cycle of the engine more oxygen, letting it burn more fuel and do more work, thus increasing power.