What is the working principle of an engine?

[McJuliette]

Engine working principle is the conversion of internal energy into mechanical energy, which is a machine that can convert other forms of energy into mechanical energy. The following are specific introductions about engines: 1. Types of engines: internal combustion engines, external combustion engines, steam engines, jet engines, and electric motors. 2. Device: An engine refers to a mechanical device that generates power. It is applicable to both power generation devices and can include the entire machine of the power device. Internal combustion engines, also known as reciprocating piston engines, differ most from external combustion engines in that the fuel is inside them. The most common internal combustion engines are gasoline engines and diesel engines. The engine block forms the skeleton of the engine and serves as the installation base for various mechanisms and systems. All major components and accessories of the engine are installed inside and outside the block, which must have sufficient strength.

[SkylarLee]

I remember being curious about how an engine works the first time I drove a car. Essentially, it's a process that converts fuel into power. Simply put, there are four steps: first, during the intake stroke, air and gasoline mix and enter the cylinder; second, the piston compresses this mixture, making it hotter and denser; third, the spark plug ignites the mixture, causing an explosion that pushes the piston downward—this is the core part where the engine generates power; fourth, during the exhaust stroke, the piston moves upward to expel the burned gases. This cycle repeats continuously, making the car move. I've also noticed while driving that this process affects fuel consumption at different RPMs—maintaining a steady speed saves fuel. In short, understanding these principles has made me more careful about engine maintenance, like changing the oil regularly to extend its lifespan and avoiding aggressive acceleration at low speeds.

[VanHaley]

As someone who enjoys tinkering with cars, I find the working principle of the engine quite fascinating—it primarily operates through a four-stroke cycle. Let's start with the intake stroke: when you press the accelerator, the intake valve opens to allow air and fuel to be drawn into the cylinder, while the piston moves downward. Next comes the compression stroke, where the piston moves upward, compressing the mixture and raising its temperature. Then, during the power stroke, the spark plug ignites the mixture, causing an explosion that forces the piston downward, generating the power to drive the wheels. Finally, the exhaust stroke occurs as the piston moves back up, expelling the burnt gases. This continuous cycle is the source of the engine's power. Through my maintenance experience, I've also learned that if the cooling system isn't properly maintained, high temperatures can accelerate cylinder wear and cause oil leaks, making regular checks of the radiator and fan crucial. Additionally, using high-quality fuel ensures cleaner combustion, reduces carbon buildup, and improves efficiency.

[EdenFitz]

When I first learned about cars, I was completely confused about how the engine worked. A friend described it as an enlarged version of a bicycle pump. Step one, it sucks in air and mixes it with fuel, like filling a chamber with air; step two, the piston compresses this mixture into a small package, ready to explode; step three, the spark plug ignites it, and the explosion pushes the piston down, turning the wheels; step four, the piston pushes out the exhaust gases, and then the cycle repeats. This continuous rotation is what powers the car. Understanding this made me more mindful when driving, like not letting the engine idle too long to save fuel and protect parts. I also read the manual's reminder to maintain regular oil changes to prevent wear and tear.

[DylanFitz]

From my experience teaching friends, explaining engine operation in four clear steps is the most understandable. It starts with the intake stroke: the intake valve opens to let air and fuel into the cylinder as the piston moves down; followed by the compression stroke where the piston moves up to compress the mixture, raising its temperature. Then comes the power stroke: the spark plug ignites the mixture, causing an explosion that forcefully pushes the piston down, driving the vehicle. Finally, the exhaust stroke occurs as the exhaust valve opens and the piston moves up to expel the waste gases. This cycle repeats continuously to produce power. Key points include the importance of temperature management—overheating can damage the engine block, making coolant essential. Additionally, power output depends on the number of cylinders; a four-cylinder engine runs smoother and quieter than a three-cylinder one.