高速电弧喷涂枪结构优化的有限元模拟

Optical Design of Wire Arc Spray Gun Based on Finite Element Modeling

采用有限元法模拟了高速电弧喷涂枪二维气流场的分布.通过计算比较了收缩型和缩扩型喷管的流场差异,同时分析了不同的丝材夹角、丝交点离喷管出口距离等喷枪结构参数下喷枪气流场行为.结果显示,缩扩型喷管更有利于熔滴的雾化,丝交点离喷管出口距离减小至0、丝夹角为40°时更有利于熔滴的加速.基于以上模拟结果,优化设计了一种新型的高速电弧喷涂枪.喷涂粒子的形貌实验表明,新型喷枪的雾化粒子粒度比原始喷枪更细、分布更均匀.

The effect of different gun configuration parameters on the external gas flow is investigated by using a two-dimension finite element model.The flow distribution of the gun with different configurations is calculated,such as converging type and converging/diverging type nozzles,location of the two wires intersection point and wires intersection angles.The two-dimension model provides qualitative results that the converging-diverging type nozzle is more favorable to droplets atomization,and has shorter distance from the intersection point to the exit,and has a moderate intersection angle,which is better for droplets acceleration.Finally,an innovative design alternating the original gun has been gained based on the numerical simulation.SEM photographs of the sprayed particles show that the particle size of the modified gun is smaller than that of the original gun,and the former is more homogeneous than the later.