High viscosity droplet control design and simulation

• Main Authors: Lin, Hshow-Ting, 林秀婷
• Other Authors: Cheng, Pi-Ying
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/jaz82v

碩士 === 國立交通大學 === 工學院精密與自動化工程學程 === 107 === ABSTRACT The purpose of this study was to use ANSYS-fluent to create a high-viscosity droplet simulation design module, using the PVA650 machine for selective coating of the dispensing system to explore the optimal parameters for stroke, air pressure and droplet discharge time. Optimized analysis using Taguchi method to assist in the planning of parameter items and values. It is expected that the high-viscosity droplet parameters in this study can be applied to the process and parameter design and application of precision parts spraying in PCB boards. In the field of science and technology, all kinds of high-viscosity Dispenser help the droplets to reach the ideal value quickly and accurately, and adhere and coat with the object to achieve the ideal spraying process and purpose. In this experiment, the parameters of 620X（viscosity of 225 cps） glue were used to carry out the simulation analysis test of droplet formation, and the ANSYS-Fluent simulated air pressure was 35 psi、40 psi and 45 psi; the stroke was 3 mm, 4 mm and 5 mm; the droplet discharge time was 0.02s、0.04s and 0.06s,etc. as experimental parameters,using this experimental parameter as a method of extruding droplets by an actuator, by means of extrusion of air pressure, pushing the liquid in the syringe at a suitable air pressure, in the form of droplets The squirt is simulated; the simulation results are analyzed and discussed with the experimental tests performed by the actual machine.In order to verify the formation effect of the droplets and the simulation comparison results, the 620X glue and the designed viscosity 225cps viscosity were selected as the analysis liquid.Using ANSYS-Fluent as the analysis platform for droplet forming simulation.The analysis process is solved by using the PISO(Pressure Implicit with Splitting of Operator) method for analysis and simulation.Comparative analysis of droplet sizes formed by simulation and experimental results．The optimal process parameters of high viscosity droplets were screened by the Taguchi method to achieve the desired target droplets. Finally, the validated simulation system will be applied to the droplet extrusion simulation of higher viscosity spray materials or other high viscosity bodies as comparison and reference data for the extrusion experiments. This study specifically explores the process of forming droplets with higher viscosity. The example is simulated FP-5000L (silver glue). The viscosity of the glue is expected to be 11000~16000 cps. The purpose of this study was to investigate the adhesion of spray glue in new LED lamps. The use of droplet-shaped glue extruded from pneumatic actuators as a grain-like material, and the design parameters of a solid-state adhesive such as a PCB are used as application references. Keywords: high viscosity droplets, droplet formation simulation, valve, viscosity, PISO analysis