4-Stroke & 2-Stroke Engine | Its Parts & Working Explained

Summary

This video explores the workings of internal combustion (IC) engines, highlighting key components such as cylinders, pistons, crankshafts, and valves. It explains the operation of various types of IC engines, including four-stroke petrol, diesel, two-stroke petrol, and diesel engines. The video provides an in-depth explanation of each engine's working principle, the combustion cycle, and the differences in their mechanisms. Additionally, it contrasts the advantages and disadvantages of two-stroke and four-stroke engines, covering factors like power output, efficiency, and maintenance. Overall, the video offers a comprehensive understanding of engine design and functionality.

Takeaways

• 😀 Internal Combustion (IC) engine ignites and combusts fuel inside the engine under high pressure, with its first commercial success around 1860.
• 😀 The term 'internal combustion engine' refers to engines with intermittent combustion, such as two-stroke and four-stroke piston engines, as well as variants like the Wankle rotary engine.
• 😀 Key parts of an IC engine include the cylinder block, piston, crankshaft, cylinder head, piston rings, valves, and more.
• 😀 The four-stroke petrol engine operates on the autocycle principle and requires two revolutions of the crankshaft to complete intake, compression, power, and exhaust strokes.
• 😀 In a four-stroke petrol engine, the spark plug ignites the air-fuel mixture during the power stroke, resulting in combustion that drives the piston downward.
• 😀 A four-stroke diesel engine operates similarly to the petrol engine, but with a fuel injector replacing the spark plug, using compression ignition.
• 😀 The two-stroke engine completes a power cycle with just one revolution of the crankshaft, resulting in higher power output compared to a four-stroke engine.
• 😀 The two-stroke petrol engine compresses the air-fuel mixture in the cylinder and initiates combustion with a spark, which then drives the piston downward.
• 😀 Diesel engines, including two-stroke variants, utilize high-pressure fuel injectors for compression ignition, and the exhaust gases are expelled as the piston moves down.
• 😀 Advantages of two-stroke engines include higher power output, smaller size, and simpler gear arrangement, but they suffer from higher fuel consumption and thermal inefficiency compared to four-stroke engines.

Q & A

What is an internal combustion (IC) engine?

An internal combustion engine (IC engine) is an engine where ignition and combustion of fuel occur inside the engine. It operates on the principle that fuel is ignited under high pressure in a combustion chamber, generating mechanical work.

Who invented the first commercially successful IC engine?

The first commercially successful IC engine was created by ATN Lenor around 1860.

What are the main components of an IC engine?

The main components of an IC engine include the cylinder block, cylinder, piston, piston rings, connecting rod, crankshaft, crankcase, valves, spark plug (petrol engine), fuel injector (diesel engine), and the crank pin.

How does a piston work in an IC engine?

The piston is a moving part in the combustion chamber that converts energy released during combustion into mechanical work. It moves up and down, driving the crankshaft to produce rotational motion.

What is the role of the spark plug in a petrol engine?

In a petrol engine, the spark plug ignites the compressed air-fuel mixture, initiating combustion.

How does the four-stroke petrol engine work?

In a four-stroke petrol engine, the cycle consists of four strokes: intake, compression, power, and exhaust. The cycle requires two revolutions of the crankshaft to complete, with each stroke having a specific function in the combustion process.

What distinguishes a four-stroke diesel engine from a petrol engine?

A four-stroke diesel engine works on the diesel cycle, where air is compressed to a high temperature and pressure, and diesel fuel is injected into the chamber, igniting due to the high pressure. In contrast, a petrol engine uses a spark plug for ignition.

What is the basic function of the valves in an IC engine?

The valves in an IC engine control the intake of air and fuel mixture into the cylinder and the exhaust of gases from the cylinder.

What are the advantages of a two-stroke engine compared to a four-stroke engine?

A two-stroke engine is more compact, lighter, and operates with greater uniformity in crankshaft turning effort. It requires less space and simpler reversing gear arrangements.

What are some disadvantages of two-stroke engines?

Two-stroke engines tend to have higher fuel consumption, less thermal efficiency, and greater wear and tear due to the high-speed operation of moving parts. They also generate more noise and pose a greater risk of fire due to high cylinder temperatures.