Why do diesel engines vibrate with noise?
We also know that in the gasoline engine, knock is fault phenomenon. To produce motion power and engine piston in the opposite direction is called detonation combustion of combustible gas, not only bad detonation engine damage, increased fuel consumption, and will have a lot of noise. In the EFI gasoline engine, with a knock sensor, through the critical point ECU ignition timing control for engine knock and knock out. And in the diesel engine, the fuel itself is by compression ignition, the gasoline engine and compression ignition detonation conditions when the same, so inevitably will produce a lot of noise.x0d in addition to the combustion of different causes more than noise. The other mechanism of diesel engine will produce more noise, such as the fuel pump of diesel engine. Unlike gasoline engine, the compression stroke when the gasoline engine is A mixture of oil and gas compression, while the diesel engine is a compression of pure air. Because, in order to make the diesel in cylinder combustion more fully, and will not cause unnecessary knock, the diesel engine is a piston in nearly reach the start vertex of the injection compression. You want to in such a high pressure environment, must choke a very large supply pressure to ensure the normal operation of the engine.
It is popular as the diesel fuel and gasoline as firewood, straw, straw fire on a stick, but not resistant to burning, and firewood is not so easy to ignite but will burn a lot of resistance than straw. So, according to the characteristics of diesel, we would not like to ignite the gasoline as simple as by electric spark to light diesel oil, diesel fuel can only rely on the pressure so doomed to a point. As a result of the diesel engine compression ratio must be set very high, generally around 20. This structure is very reliable, although the fuel pressure and that the combustion is sufficient, but the high compression ratio of the engine will run smoothly by the great effect. Complete combustion gas in the cylinder will make a sudden rapid expansion, so that the piston will have a rapid downward force, this is because the engine inertia, the piston is not moving down smoothly, it will guide Knock cylinder, that is, piston skirt and cylinder wall collision, which is one of the diesel engine
You can not open the engine cover between diesel engine? Of course! Would be able to listen to them, the general diesel engine noise and vibration will be better than the gasoline engine, it also can not see the tractor, the way you can hear "ta... Ta... Ta... Ta..." Sound. But now the diesel car is not like a tractor that is simply mounted on the frame, no noise, exhaust noise reduction without filtering. Even now the highest technology content of diesel engines, in the control of vibration and noise of the engine, there are still a big gap with the gasoline engine below. We have to tell.x0d the reason first, it has great relationship with the diesel fuel. This fuel in diesel antiknock, ignition (ignition), viscosity, volatile, combustion rate is lower than that of gasoline.
