Views: 84 Author: Site Editor Publish Time: 2021-05-20 Origin: Site
Generally speaking, the 4 stroke 6 cylinder turbocharger diesel engine with petrol can still be started, but it will be weak, and the work is rude, jittery, slow, and noisy, so it cannot be used normally, and it may even cause damage to the diesel engine. Therefore, when it is found that the diesel engine is mistakenly added petrol, it should be stopped immediately, do not start the diesel engine, and completely discharge the petrol and re-add diesel.
The ignition point and combustion mode of diesel and petrol are different, and the engine and fuel must be matched to work properly.
Diesel and petrol engines use two completely different fuels. Diesel has a low spontaneous combustion temperature of about 220°C, and its viscosity is not easily volatile. Petrol has a high spontaneous combustion temperature of about 415°C to 530°C, and its viscosity is small and easy volatile. The working principles of diesel engines and petrol engines are also different. The ignition mode of diesel engines is compression ignition and the ignition mode of petrol engines is ignition.
The compression ratio of the powerful 12 cylinder turbocharger diesel engine is generally between 16-22, the high can reach 26. And the compression ratio of the petrol engine is smaller, generally between 8-11, the high can reach 14. Generally speaking, the higher the compression ratio of the engine, the higher the thermal efficiency, but why is the compression ratio of the petrol engine so low? It is mainly to avoid deflagration. The combustion characteristic of petrol is that the combustion speed is very fast. When the compression ratio is too large, the compression of petrol and air will be too violent. After being ignited by the spark plug, the combustion will be too violent and form a deflagration. Deflagration is extremely damaging to the engine, so in the design of petrol engines, the compression ratio will be controlled in a lower range to avoid knocking.
The cylinder bore of the petrol engine is small, generally not exceeding 100mm, and the cylinder bore of the 1800rpm 4 stroke turbocharger diesel engine can be made very large, and the cylinder bore of some ships can reach more than 1 meter. This is mainly related to the combustion characteristics of diesel and petrol. The petrol engine is a kind of ignition, in this way, when the cylinder diameter is too large, the mixed gas in the end of the cylinder will burn before the flame front reaches, forming a deflagration. The diesel engine is a compression ignition method. When the mixture is combusted, it will form multiple flame centers, and no deflagration will occur. Therefore, it is okay to have a large cylinder diameter.
The greater the piston stroke of the engine, the greater the general torque, but the lower the speed. The combustion speed of diesel is slow and the compression ratio of the 227kw four stroke turbocharger diesel engine is large. In actual use, it tends to use long stroke and low speed. The combustion speed of petrol is fast and the compression ratio of gasoline engine is small. In actual use, it tends to use short stroke and high speed. Due to the large compression ratio, high pressure, and long stroke of diesel engines, the components of general diesel engines have been strengthened. Diesel engines look bulkier and larger than petrol engines.
Why do petrol engines use spark plug ignition? The compression ratio of the 12v 550kw turbocharger diesel engine is large. At the compression top dead center, the temperature in the cylinder can reach about 500-800 degrees, and the ignition point of the diesel is about 220 degrees. At this time, the diesel can be injected to burn. The compression ratio of the petrol engine is small. At compression top dead center, the temperature in the cylinder can reach about 300-400 degrees, and the ignition point of petrol is about 427 degrees. At this time, the petrol can not be burned when injected, so the petrol engine needs to be ignited with a spark plug.