The fuel nozzle uses the liquid pressure to generate a fine hollow spray to provide the engine with atomized fuel, thereby improving the fuel efficiency. Fuel nozzles can be divided into pressure type and siphon type fuel nozzles due to different fuel supply methods. The pressure fuel nozzle is a single-fluid medium and high pressure atomizing nozzle. It usually uses a small aperture and fine flow to achieve the effect of wet mist. Generally, it has filters of different meshes. Grinding micro-holes; siphon fuel nozzle is a two-fluid nozzle that atomizes liquid with air pressure to produce an extremely fine atomization effect.
Pressure fuel nozzles have several important responsibilities. They not only need to provide accurate fuel quantities, but also atomize the fuel into extremely fine droplets. Can burn 100% completely. As the fuel is atomized into tiny droplets, each droplet is tightly wrapped by air. The excellent ratio of air to fuel is an important factor for the burner to achieve complete combustion. The atomization process can be described in three stages:
After the fuel is pressurized by the pump, it is sent to the nozzle. When the fuel passes through the filter on the nozzle, the filter will block the impurities in the fuel to ensure the cleanliness of the fuel and prevent the nozzle from being blocked. The filtered fuel will be pushed to the nozzle. ‘Tangential Slots’, the tangential slot has two important functions, the first function is to accurately control the amount of fuel passing through the nozzle, the width and depth of the tangential slot, the size is about 1/40 of an adult hair, tiny can only be seen through a microscope.
The second function of the tangential metering groove is to guide the fuel to the Swirl Chamber of the nozzle, so that the fuel immediately rotates at a high speed.
The high-speed rotating fuel has a hollow tubular shape similar to a tornado. After being pushed, it contacts the wall of the nozzle and is sprayed toward the nozzle. After the fuel leaves the nozzle, it will continue to rotate, but only within a very short distance. Inside, the liquid film is part of the formation of the spray after the fuel leaves the nozzle orifice, but has not yet broken down into tiny droplets.
When the fuel leaves the nozzle at a distance of about 0.4mm (1/64″), the centrifugal force separates the rotating fuel and makes the droplets form immediately. Imagine if we tie a stone to the plastic rope and spin the rope quickly, When we loosen the rope in our hand, the stone and the rope must fly straight out in the tangential direction. Although this is only a simple physical property, the fuel nozzle uses this principle to generate atomization.
The atomized fuel will not rotate. If the atomized fuel will rotate, it is definitely due to the influence of the air mixing mechanism on the burner. Please remember that the pressure fuel nozzle does not have any rotating mechanism, and the only thing that will rotate during the atomization process. The one is ‘fuel’.