What is the principle of a fuel injector?
2 Answers
The fuel injector generates high pressure inside its body, which acts on the conical surface of the nozzle. When the oil pressure exceeds the set value, the nozzle valve core opens, and high-pressure fuel is sprayed out from the small holes of the nozzle in a mist form into the engine cylinder for combustion, driving the piston to reciprocate. More relevant information is as follows: 1. The fuel injector is a highly precise component with extremely high machining accuracy, requiring a wide dynamic flow range, strong resistance to clogging and contamination, and excellent atomization performance. The fuel injector receives the fuel injection pulse signal from the ECU and precisely controls the fuel injection volume. The spray characteristics of the fuel injector include atomization particle size, fuel mist distribution, spray direction, range, and diffusion cone angle. These characteristics should meet the requirements of the diesel engine combustion system to ensure proper mixture formation and combustion, achieving higher power and thermal efficiency. 2. The electronically controlled fuel injector is the most critical and complex component in the common rail system, as well as the component with the greatest design and process challenges. The ECU controls the opening and closing of the solenoid valve to inject fuel from the high-pressure rail into the combustion chamber with optimal injection timing, injection volume, and injection rate. To achieve an effective injection start point and precise injection volume, the common rail system employs components with hydraulic servo systems and electronic control elements.
As a car enthusiast, I find the principle of fuel injectors particularly fascinating. It's essentially an electronically controlled nozzle where pressurized fuel from the fuel system is delivered to the injector. The vehicle's ECU sends electrical signals based on engine demand - when the solenoid coil is energized, the valve opens, spraying gasoline into the cylinder. The key lies in precise metering and timing - too much fuel wastes gasoline, while too little results in insufficient power, affecting air-fuel mixture combustion. Modern injectors can open and close about a thousand times per second, with high-pressure injection enabling better fuel atomization, more complete combustion, and significantly improved engine efficiency. If injectors get carbon buildup or become clogged, the car may stall or experience poor acceleration, making regular cleaning crucial. In principle, this is worlds apart from old carburetor systems, relying entirely on electronic control to ensure smoother operation and better fuel economy. I often hear injection patterns can also be adjusted for different driving conditions, like injecting more fuel during uphill climbs to ensure quick power response.
