电弧喷枪流场的数值模拟研究

Numerical studies of fluid dynamics in the flow field of a Two - Wire - Arc spray gun

电弧喷枪流场特性是影响电弧喷涂质量的关键因素之一。运用商用流体计算软件Fluent，对手持式高速电弧喷枪头部及枪外射流进行了模拟计算，通过分析可以看出，雾化射流具有不对称、湍流等特点，其射流速度分布有明显的先递增后衰减的规律，在流场推动下，雾化的金属粒子首先被流场加速，到达最大值后速度开始衰减，随着喷涂距离的增加，粒子的速度逐渐下降，特别是靠近流场外部的粒子，速度的下降更快，最终失去了与基底的结合动能，成为灰尘，飞散到环境之中，这既浪费了材料，又污染了环境。为了提高沉积率，保证涂层质量，喷涂距离的控制显得非常重要。

The characteristic of fluid dynamics is one of the key factors, which affect coating quality. In the paper, the present work examines the fluid dynamics in the flow field of a two - wire - arc spray gun. The asymmetric character and turbulent behaviors are obtained with numerical computation and simulation based on Fluent. Moreover, velocity distribution is found that the mental droplets velocity declined gradually after acceleration near the exit of the jet nozzle, especially the droplets on the edge of the fluid lost their kinetic energy drastically and dissipate into ambient environment, which produces waste and pollutants. In order to increase the deposition ratio and coating quality, spray distance should be paid cautious attention.