understand the advantages and disadvantages of gasoline and diesel engines

A diesel engine is an engine that burns diesel to obtain energy release.

Diesel engine advantages:

1. High thermal efficiency

2. Low weight per unit power

3. Extensive use of exhaust gas turbocharging and increasing the degree of supercharging

4. The diesel engine does not have an ignition system, so it has fewer faults, is easy to maintain, and works reliably.

Diesel engine disadvantages:

The rotation speed is lower than that of gasoline engines (generally the rotation speed is 1800-3000R/MIN), the mass is large, the manufacturing and maintenance costs are high, the noise is loud, and it is difficult to start, etc. Moreover, diesel engine vehicles often drive on the highway. When the vehicle runs for a long time, the engine temperature and pressure are high, which produces more soot and carbon deposits in the cylinder. The engine oil is also easily oxidized to produce colloid, so the diesel engine oil is required to have good high temperature. Purity. However, the shortcomings of diesel engines are being overcome. With the improvement of diesel engines' speed indicators, quality indicators, noise indicators, etc., and the diesel engines emitting much less harmful gases than gasoline engines (especially less CO), they are used in small and medium-sized cars. The trend of industrial diesel engine is becoming more and more obvious. It is a compression ignition type. The fuel relies on the heat generated by air compression in the cylinder to ignite. That is, air compression will increase the temperature. When the temperature of the compressed air is higher than the ignition point of diesel, diesel will burn.

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

Gasoline engine advantages:

The gasoline engine has high speed (currently the speed of gasoline engines for trucks is generally 3000-4000R/MIN, and the maximum speed of gasoline engines for cars can reach 5000-6000R/MIN), good adaptability, smooth and gentle operation, easy and labor-saving operation, light weight, and low noise Small, low cost, easy to start, etc., it is widely used in cars, small and medium-sized trucks and military off-road vehicles.

Gasoline engine disadvantages:

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

As for whether a diesel car or a gasoline car is better? 

In fact, the life of a diesel engine is much longer than that of a gasoline vehicle. Did you know that the distance traveled by a long-distance bus in one year is equivalent to the mileage you drive a private car in a lifetime? The engine of a long-distance bus generally needs to run one million kilometers before it is overhauled. Some better Some diesel cars don't require major overhaul until the car is scrapped. Diesel engines have good fatigue resistance and will not suffer from power failure like gasoline cars when running at high speeds or climbing hills for a long time, especially when equipped with air conditioning. But its shortcomings are also obvious. It is noisier than gasoline vehicles, speeds up slowly, takes longer to warm up in winter, and vibrates more. Diesel vehicles are really not easy to break, so don't make random guesses.

Many friends have never understood the relationship between horsepower, power, and torque, and what we usually call 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 the gasoline The horsepower (power) of the engine is two different things when it is actually working, because the rotation speed of the gasoline engine is about 6,000 rpm, while the rotation speed of the diesel engine is about 3,000 rpm. Therefore, the torque of the diesel engine with the same horsepower (power) (we Generally speaking, the power) is twice (approximately) that of a gasoline engine, and the speed of a gasoline engine with the same horsepower (power) is twice that of a diesel engine (approximately). So we feel that when actually driving, a diesel car with the same horsepower is much more powerful than a gasoline car, and a gasoline car with the same horsepower is much faster than a diesel car.

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

Due to their structural differences, the cost of general diesel engines of the same brand is higher and their durability is stronger. Gasoline engines are lighter. More details please contact SWAFLY