Frist,The working principle of the single and double pressure of the spray pump head
The single-channel pressure spray pump head is also called a simple centrifugal nozzle. As the name implies, it uses a swirling member in the nozzle to generate liquid rotation, and accelerates the FFJ stroke heart diffusion cone oil film in the converging channel, using the high-speed difference between the liquid and the outside air And broken and atomized. The centrifugal force of the cyclone is used, so the cyclone is the key component. The swirl chamber and nozzle connected to the swirler (chip) are equally important. They can be combined into one (collectively called atomizer), or they can be divided into single parts.
The dual oil pressure spray pump head has two oil paths (main and auxiliary oil paths or primary and secondary oil paths) to supply oil. When the fuel supply of the combustion chamber is low, that is, under low operating conditions (such as the slow engine state of the engine), only the auxiliary oil channel (one channel) supplies fuel. As the fuel supply increases, the fuel pressure increases to a certain value. The oil separation valve (spring valve) inside or outside the nozzle is opened, and the main and auxiliary oil channels supply oil at the same time. The dual-channel is an improved type of single-channel pressure spray pump head. Its outstanding advantages are the large oil volume adjustment range, and it can ensure low operating conditions (low oil supply). Due to the small diameter of the auxiliary oil channel nozzle, the oil pressure is still available. Higher, can obtain better atomization quality (especially for the two-way double-chamber dual-nozzle nozzle, especially for the two-way single-jet nozzle nozzle to reliably increase the swirl speed), can meet the aviation gas turbine under different working conditions of high and low altitude Requirements for stable combustion and complete combustion. Therefore, the two-way nozzle has been widely used in aviation gas turbines, and it is also widely used on ground combustion engines.
Second, the structural characteristics of the single-channel and double-channel pressure of the spray pump head
The single-channel pressure spray pump head has a simple structure and good atomization quality. It is widely used in various types of combustion devices. Although it has a small range of fuel ratio, it has been widely used in the afterburner of the aircraft. It is currently used in the main combustion chamber. It is still used as the starting nozzle and the working nozzle, and the combined atomization device in the high-performance aviation gas turbine is used as the towel nozzle. In addition, the pressure atomization method of non-combustion equipment, such as spray drying equipment, also uses a single-channel pressure spray pump head. It is also used in burners (or burners) on industrial furnaces and boilers.
There are many types of dual-channel pressure spray pump heads. Here we introduce three types of spray pump heads: dual-channel single-chamber single nozzle nozzle, dual-channel double-chamber single nozzle nozzle, dual-channel dual-chamber double nozzle nozzle.
In order to accurately design and calculate the single-channel pressure spray pump head and dual-channel spray pump head, the current design method is based on the maximum flow principle method and the momentum equation method. In addition, on this basis, we have added or improved many design methods.