Views:98 Author:Site Editor Publish Time: 2021-04-06 Origin:Site
A powerful 12 cylinder diesel engine is an engine that burns diesel fuel for energy release. It was invented by the German inventor Rudolf Diesel in 1892. In order to commemorate the inventor, diesel is expressed by his surname Diesel, and the diesel engine is also known as diesel engine.
In fact, the working process of KPV510 12 cylinder diesel engine is the same as that of gasoline engine, and each working cycle also experiences four strokes of intake, compression, work and exhaust.
Pure air is inhaled in the intake stroke of high quality 12 cylinder diesel engine. When the compression stroke is close to the end, the oil pressure of the diesel oil is increased to more than 10MPa by the oil injection pump. It is injected into the cylinder through the oil injector, and mixed with the compressed high-temperature air in a very short time to form a combustible mixture. Due to the high compression ratio of diesel engine (usually 16-22), the air pressure in the cylinder can reach 3.5-4.5MPa at the end of compression, and the temperature can reach 750-1000K (while the mixture pressure of gasoline engine will be 0.6-1.2MPa, and the temperature can reach 600-700K), which greatly exceeds the spontaneous combustion temperature of diesel. Therefore, diesel fuel will ignite and burn automatically after mixing with air in a short period of time after it is injected into the cylinder. The air pressure in the cylinder rises rapidly to 6-9MPa and the temperature rises to 2000-2500K. Driven by high pressure gas, the piston moves downward and drives the crankshaft to rotate to work. The exhaust gas is also discharged into the atmosphere through the exhaust pipe.
The fuel supply system of ordinary diesel engine is driven by engine camshaft, and the diesel oil is delivered to the fuel chambers of each cylinder by means of high-pressure oil pump. This mode of fuel supply changes with the change of engine speed, so it can not achieve the best fuel supply under various speeds.
The common rail jet type oil supply system is composed of high pressure oil pump, communal oil supply pipe, oil injector, electronic control unit (ECU) and some pipeline pressure sensors. Each oil injector in the system is connected with communal oil supply pipe through its own high pressure oil pipe, which plays a role of hydraulic pressure storage for the oil injector. During operation, the high-pressure oil pump delivers the fuel to the communal oil supply pipe with high pressure. The high-pressure oil pump, pressure sensor and ECU work in a closed-loop manner, which can accurately control the oil pressure in the communal oil supply pipe, and completely change the phenomenon that the fuel supply pressure changes with the engine speed.
Its main characteristics are as follows.
① The oil injection timing and fuel metering are completely separated, and the injection pressure and injection process are timely controlled by ECU.
② According to the working condition of the engine, the injection pressure, injection starting point and duration can be adjusted to achieve the best control point.
③ It can achieve high injection pressure and pre injection of diesel oil.
The advantages of high speed 12 cylinder diesel engine are large torque and good economic performance. It is widely used in large diesel vehicles.