Abstract:A new type of gasliquid mixing electrostatic spraying blade was designed to eliminate the drawbacks in the existing antirust oil spraying machines with a single oil spray, for instance, high oil consumption, serious environmental pollution, poor adsorption and deposition of spraying oil and so on. The geometric parameters and mathematical model for the spraying blade were established, thus its key design parameters were determined based on the structure of existing electrostatic spraying blade. It was shown that there is a vortex flow in the mixing chamber of the new spraying blade, causing the oil and gas are mixed thoroughly. The gas velocity is distributed axisymmetrically with 4.310 m/s maximum and 0.287 m/s minimum velocity in the chamber. The droplet velocity at the outermost contour line is about 0.293 m/s. The droplet velocity is uniform at the outlet of the spraying blade and the droplets themselves are distributed divergently, leading to a relatively wide spraying range. After the second gasoil mixing, the droplet velocity is lowered gradually in the divergent gap between the blade outlet and the second mixing chamber; the expandable gas bubbles induce the oil droplets to be broken once more. When the spraying simulation times are 0.000 1 s and 0.002 6 s, the maximum droplet size at the outlet of spraying blade are 70.76 μm and 32.94 μm, respectively. Additionally, with increase of simulation time, the distribution of droplet size becomes stable, suggesting the gasliquid atomization effect and the quality of surface coating are improved greatly.
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