Use of Centroidal Voronoi Diagram to find optimal gate locations to minimize mold filling time in resin transfer molding

Abstract

In Resin Transfer Molding (RTM) processes, liquid resin is injected into a dry reinforcement structure to create a composite part within given time limits. To reduce the fill time, resin may be injected into the mold through multiple gates. The minimum number of gates and their locations needs to be determined. To reduce the number of scenarios to be simulated, an iterative method is implemented for multiple-gate injection optimization. The inlet nodes on the mesh surface are used to generate a Voronoi Diagram of the mold geometry. Then the optimal Centroidal Voronoi Diagram (CVD) of the mold surface is searched iteratively. It is shown that the generation points associated with the optimal CVD correspond with the gate locations that yield the shortest fill time. The results are compared with exhaustive search and genetic algorithms results to illustrate the efficiency and accuracy of CVD method.

Multi-objective optimization of Resin Infusion

“…Reduction in filling time of about 15% can be achieved compared to empirical gate location selections [7][8][9]. An optimization methodology based on Centroidal Voronoi Diagram has been implemented to minimize filling time by optimal gate placement showing a 93% reduction in required simulations compared to GA [10]. However, this approach is likely to get trapped in local minima when applied to symmetric geometries.…”

Nonisothermal simulation on pressure during resin transfer molding

“…But increasing injection speed will also increase the mold internal pressure, resulting in fiber damage and mold deformation, seriously affecting quality of products . The mold internal pressure and filling time can be reduced by optimizing the position of injection/vent port, but the position of injection/vent port is limited by the shape of the products and sometimes cannot be optimized. Meanwhile, an effective way to reduce mold pressure is to reduce the viscosity of the resin by heating the mold and injection resin .…”

Prediction of Defect Formation during Resin Impregnation Process through a Multi-Layered Fiber Preform in Resin Transfer Molding by a Proposed Analytical Model

“…In the processes, high pressure for both efficient mixing and fast injection of resin is often used and the critical process control is required for successful production of composite parts without defects. Much effort for flow simulation of the resin transfer molding has made it possible to predict some important results such as mold filling time and formation of unfilled area [ 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. However, many portions of defects in size, mechanical properties and appearance of the final product are caused by undesirable deformations of fiber preform during the process [ 11 , 12 , 13 ], which has not been considered in the general mold filling simulations.…”