Mathematical Modeling and CFD Analysis with Experimental Investigation of the Geometry of the Grooves Created with CO2 Laser on the Polycarbonate Plate

Abstract

Mathematical modeling of micro-scale grooves was made on the polycarbonate plate. The micro-scale groove's surface and cross-section structure, created by scanning at a constant speed using a 30 W beam with a CO₂ laser, was examined with a high-resolution optical microscope and the groove geometry was precisely measured. Using the data obtained from the measurements and the physical constants of the polycarbonate, mathematical modeling was made for the temperature distribution in two different directions. The Fourier Finite difference method was used to model the temperature distribution along the line on the polycarbonate surface. The experimental studies with 5 different laser beam powers were carried out again to prove the accuracy and validity of the model. Lateral temperature distribution on the surface of the material and vertical temperature distribution towards the depths of the material were investigated separately. The error rates between the proposed mathematical model and the experimental results are between 3.24 % and 8.44 %. Since the experimental results are in good agreement with the proposed model, it can be said that the proposed mathematical model is a reliable model. Moreover, the temperature distributions both in the lateral direction and vertically into the material were modeled with CFD-Computational Fluid Dynamics. The sources of the differences between the ignition, melting and glass transition temperature obtained from the CFD analysis and the actual temperature values were discussed.