为解决实际工业中除雾器在高气速时分离效率明显降低的问题,利用除雾器分离实验装置,以水为实验介质,采用电火花线切割技术在叶片表面构建仿生微结构实现表面疏水化,考察了表面润湿性对除雾器分离效率和压降的影响。结果表明,仿生微结构的疏水功能和减阻效应良好,表面液膜的排液速率明显加快。当气速超过5 m/s时,其液膜厚度相对较薄,可有效抑制液滴的二次夹带,提升分离效率。同时,疏水型梯形除雾器内的流场分布较平缓,流动阻力小,总压降约为带钩型梯形除雾器的一半。因此,疏水型梯形除雾器兼具高效率和低阻力特性,综合分离性能最佳。
The trapezoidal demisters are commonly used to remove droplets over 10 ?m in the field of natural gas purification. In order to solve the problem that the separation efficiency of the demisters obviously reduced at high gas velocity in the actual industry, the biomimetic microstructure was constructed on the surface by the wire electrical discharge machining (WEDM) technology to obtain a hydrophobic surface. Furthermore, the effects of surface wettability on the separation efficiency and pressure drop for the demisters were evaluated experimentally using atomized droplets. The results showed that the surface with biomimetic microstructure had good hydrophobic function and resistance reduction effect, which accelerated the drainage rate of liquid film. When the gas velocity exceeded 5 m/s, the liquid film thickness was relatively thin, which effectively suppressed the re-entrainment phenomenon of the droplets and improved the separation efficiency. In addition, the flow field distribution in the hydrophobic trapezoidal demisters was relatively flat, and the flow resistance was very small. The total pressure drop was only half of the demisters with hook. Therefore, the composite separation performance of the hydrophobic trapezoidal demisters with high efficiency and low resistance was optimal.