【摘要】 针对马鞍脊面喷涂成膜荷电气液两相流耦合过程,采用磁流体动力学和欧拉-拉格朗日法构建静电场、气液两相流模型、湍流模型和沉积模型,基于计算流体动力学的方法,考察了不同喷涂电压下的喷涂域电势分布、液滴运动轨迹和涂膜沉积分布。仿真结果表明:在中心轴附近空气流速较大,而喷涂流场气相速度随着流场扩散逐渐减小;同一喷涂电压下,在扩散区中,喷涂流场向四周扩散的形态基本相同,但在成膜区不同;喷涂流场中的大粒径液滴和中等粒径液滴是成膜的主要来源;喷涂电压增大,电场强度随之增大,马鞍脊面喷涂流场扩散范围扩大,涂膜覆盖范围也就扩大,涂料转移率增大,涂膜厚度均匀性更好;不同喷涂电压下在马鞍脊面的沉积分布类似于圆环形和椭圆环形。更多还原

【Abstract】 Aiming at the coupling of charged electric-hydraulic two-phase flow during the spraying process on a saddle ridge surface, the electrostatic field, gas-liquid two-phase flow model, turbulence model, and deposition model were constructed using magnetohydrodynamic theory and Euler-Lagrange method. The potential distribution in the spray domain,the trajectory of the paint droplet, and the distribution of the coating deposition under different spraying voltages were calculated based on computational fluid dynamics. The simulation results show that the air velocity is high near the central axis, while the gas velocity of the spraying flow field decreases gradually with the diffusion of the flow field. At the same spraying voltage, the form of the spraying flow field spreading around is basically the same in the diffusion zone, but is different in the film-forming area. The large-sized and medium-sized droplets in the spraying flow field are the main sources of film formation. As the increasing of spraying voltage, the electric field strength increases, and the spreading range of spraying flow field on the saddle ridge surface expands, thus the coating coverage will expand, the coating transfer efficiency will increase, and the coating thickness uniformity will be better. The shape of deposits distributed on the saddle ridge surface under different spraying voltages is similar to a circular ring or an elliptical ring.更多还原