What are the differences between diesel engines and gasoline engines?
2 Answers
Here are the specific differences between diesel engines and gasoline engines: 1. Fuel supply and ignition method: In diesel engines, fuel mixing and combustion occur within the cylinder. High-pressure diesel is directly injected into the combustion chamber by the injector, mixes with air to form atomized gas, and then combusts after compression. Therefore, in terms of structure, gasoline engines have an additional complete ignition system compared to diesel engines. In gasoline engines, gasoline from the fuel pump mixes with air from the air filter in the carburetor to form a mixed gas, which enters the cylinder combustion chamber through the intake manifold and is ignited by an electric spark. 2. Fuel: Diesel engines use diesel fuel. The cetane number is an indicator for evaluating the auto-ignition performance (combustibility) of diesel fuel, the distillation range represents the volatility of diesel fuel, and viscosity is a measure of fuel fluidity. Gasoline engines use gasoline. Knocking is an abnormal auto-ignition phenomenon that may occur in gasoline engine combustion as the compression ratio and cylinder gas temperature increase. A higher octane number indicates stronger anti-knock performance, allowing for a higher compression ratio. Anti-knock additives, commonly lead compounds, are often added, hence gasoline often contains lead. 3. Corrosion resistance: Diesel engine crankshaft bearings use high-performance materials such as lead bronze or lead alloys, which have relatively poor corrosion resistance. Gasoline engine main bearings and connecting rod bearings can use softer materials with better corrosion resistance, such as Babbitt alloy.
As an experienced driver who has driven various types of vehicles, I must say the difference between diesel and gasoline engines is quite significant. Diesel cars have ample torque, making hill climbing and cargo hauling effortless, and a full tank can take you much farther on long trips, being far more fuel-efficient than gasoline. However, they accelerate slowly, produce a buzzing noise when starting, sometimes require preheating in cold winters, and aren't as comfortable for city commuting. Gasoline cars, on the other hand, start quickly, accelerate smoothly, offer quiet and steady daily driving, and have simpler, lower-cost maintenance, though they consume more fuel and are pricier at the pump. I find diesel practical for trucks, while gasoline is more convenient for family sedans. Additionally, their engine designs differ: diesel engines rely on compressed air ignition without spark plugs, whereas gasoline engines need spark plugs to ignite, which explains why diesel engines are sturdier and more durable but also heavier. Choosing between them depends on your driving habits—diesel is worry-free for frequent long-distance driving, while gasoline offers more flexibility for less frequent use.
