Three minutes to let you understand the advantages and disadvantages of gasoline and diesel engines

Advantages of diesel engine:

1. High thermal efficiency

2. Low weight per unit power

3. Extensive use of exhaust gas turbocharging and increased supercharging

4. The diesel engine does not have an ignition system, so there are fewer faults, easy maintenance, and reliable work.

 

Disadvantages of diesel engines: lower speed than gasoline engines (generally 1800-3000R/MIN), high quality, high manufacturing and maintenance costs, high noise, and difficulty in starting. In addition, diesel vehicles often drive on the road, the vehicle runs for a long time, the engine temperature and pressure are high, more soot and carbon deposits are generated in the cylinder, and the engine oil is also easily oxidized to produce colloid, so diesel engine oil requires good high temperature cleanliness. However, the shortcomings of diesel engines are being overcome. With the improvement of speed indicators, quality indicators, noise indicators, etc. of diesel engines, and the harmful gases emitted by diesel engines are much less than those of gasoline engines (especially less CO), they are installed on small and medium-sized cars. The trend of diesel engines is becoming more and more obvious. He belongs to the compression ignition type. The fuel is ignited by the heat generated by the air compression in the cylinder, that is, the air compression will increase the temperature. When the temperature of the compressed air is higher than the ignition point of the diesel, the diesel will burn. .

 

The gasoline engine is ignited, and the fuel is ignited in the cylinder by an electric spark plug.

 

Advantages: high speed of gasoline engine (currently, the speed of gasoline engine for trucks is generally 3000-4000R/MIN, and the maximum speed of gasoline engine for passenger cars can reach 5000-6000R/MIN), good adaptability, stable and soft work, convenient and labor-saving operation, light weight , low noise, low cost, easy to start, etc., so it is widely used in cars, small and medium-sized trucks and military off-road vehicles.

 

Disadvantages: high fuel consumption rate, poor economy, low exhaust gas purification index. .Because gasoline engine vehicles such as cars and passenger cars often drive in the city, they are often in a stop-start state due to road congestion, and the engine often runs at idle speed, and the temperature is low. Even under normal operating conditions, the temperature and pressure of gasoline engines are lower than diesel engines. Therefore, under the working conditions of the gasoline engine, the engine oil is prone to low-temperature sludge, so the gasoline engine oil is required to have good low-temperature sludge dispersion.

 

As for diesel or petrol cars? In fact, the life of a diesel engine is much longer than that of a gasoline car. Did you know that the distance a long-distance bus runs in a year is equivalent to the mileage of your private car for a lifetime, and the engine of a long-distance bus generally needs to run for one million kilometers before it is overhauled. Some good A little diesel car will not overhaul the engine until the car is scrapped. The diesel engine has good fatigue resistance, and it will not suffer from power failure like gasoline cars when running at high speed or climbing for a long time, especially when it is equipped with air conditioning. But his shortcomings are also obvious. The noise is louder than the gasoline car, the speed is slower, the warm-up time in winter is longer, and the vibration is larger. Diesel cars are really not easy to break, so don't make guesses.

 

Many friends have never understood the relationship between horsepower, power, and torque. We usually talk about the relationship between power. To put it simply, we all know: engine speed multiplied by torque equals power (horsepower), but the horsepower (power) of a diesel engine and gasoline The horsepower (power) of the engine is shown in two things in actual work, because the speed of the gasoline engine is about 6000 rpm, and the speed of the diesel engine is about 3000 rpm, so the same horsepower (power) The diesel engine torque (we Generally speaking, the power) is 2 times (about) that of a gasoline engine, and the speed of a gasoline engine with the same horsepower (power) is 2 times (about) that of a diesel engine. So we feel that a diesel car with the same horsepower is much more powerful than a gasoline car when actually driving, and a gasoline car with the same horsepower is much faster than a diesel car.

 

If the diesel engine and the gasoline engine are also equipped on a car, the diesel engine is generally less powerful than the gasoline engine, so it also saves more fuel. Due to the different physical properties, the gasoline engine accelerates much faster, the top speed is higher, and the diesel engine has more power (when climbing and under heavy load with air conditioning), which saves more fuel.

 

Due to the difference in its own structure, the general diesel engine of the same brand is more expensive and more durable. Gasoline engines are lighter.

 

If you are often in the city, a gasoline car is more convenient. If you often run long distances, diesel cars are strongly recommended. Whether it is high speed or mountainous area, the advantages of diesel cars are incomparable to gasoline cars. Of course, if you have a lot of money and don't care about oil, then it's another matter.