Fluid dynamics of jetting dispensing process based on simulation and experiment

Dispensing technology is widely applied in semiconductor packaging surface mounting technology, LED packaging, where needs accurate flow control. Jetting dispensing with high performance is the mainstream in dispensing technology in the future. In this paper, FLUENT software is introduced to simulate the formation process of the droplets with a two-dimensional axisymmetric swirl model. The data of pressure distribution in the interior of the dispenser under certain condition could be get during the process, then a jetting dispenser driven by mechanical collision with experiment test system is built based on simulation results to study the process of jetting dispensing. Using a High Speed Digital-Cram, the image of the glue droplets formation process in the high speed jetting dispensing could be obtained and the volume of droplets could be analyzed with Image Processing Technology. Finally, the actual volume of the glue droplets calculated by a precision measuring cylinder are compared with simulation results and the test results show that the experimental results closely match the theoretical simulation. Under the condition of normal temperature, the jetting dispenser could realize the viscosity of glue up to 1.2 Pa.s, and the volume of droplet for 86nL.