Simulation of resin filling distance during the pulling-up stage for rapid DLP printing

Abstract

In continuous digital light processing (DLP) 3D printing, the continuous lifting in the pulling-up stage may result in an insufficient resin filling for large-area structures, which limits its applications. Some researchers proposed a concept of maximum filling distance (MFD) and combined continuous and layer-wise printing for large-area rapid printing (LARP). However, the current MFD is estimated by experiments, which is far from optimal. In this paper, a computational fluid dynamics (CFD) analysis method is proposed to simulate the resin filling during the pulling-up stage for rapid DLP printing. Poiseuille flow is used to establish the CFD analysis models. The Volume of Fluid method is designed to simulate the resin filling behavior. The MFD can be predicted from the simulations. The validation of predicted results are fulfilled by actual printing processes. Printing experiments show that the proposed method can be successfully applied to different resins and printing parameters. It increases the efficiency of printing a new model or developing novel printing materials.