气动喷射点胶CFD仿真与实验研究

为了研究气压驱动的喷射点胶过程,建立了撞针气缸模型及点胶阀模型;仿真分析了气缸内压力变化对撞针运动特性的影响及撞针运动特性对点胶性能的影响。仿真结果表明:不合理的气缸管道结构会造成撞针的响应延迟;过大的驱动气压会导致气泡混入胶水。最后设计DOE实验,仿真分析了腔体尺寸对胶量、喷射速度的影响;实验分析了工艺参数对胶量的影响;并利用Minitab分析仿真和实验结果,其中腔体结构中,胶量对喷嘴直径最敏感而喷胶速度对撞针球面半径最敏感。工艺参数中,供胶压力对胶量影响最大。结论对喷射阀结构设计及工艺参数设定具有指导意义。

Simulation and Experimental Study on Pneumatic Jetting

In order to study the pneumatic jetting process, cylinder model and jetting valve model were established in this paper. The effect of pressure oscillation in cylinder on the motion characteristic of pin and the effect of motion characteristic of pin on dispensing performance were analyzed. The result shows that unreasonable channel structure in cylinder responsible for the response delay of pin. And the oversized pressure responsible for the bubble in the glue dot. DOE was designed to study the effects of structural parameter on dot weight and jetting velocity by CFD. And experimental studied the influences of the process parameters on dot weight. The results show that: In the structural parameters, the nozzle diameter is most important to dot weight and the pin spherical radius is the most important factor to jetting velocity. In the process parameters, the supply pressure is the greatest effect on the dot weight. The conclusion can provide a theoretical guidance for the design of jetting valve and process parameters setting.