Branch and bound search to optimize injection gate locations in liquid composite molding processes

• Published in: Composites. Part A, Applied science and manufacturing Applied science and manufacturing, 2002-01, Vol.33 (9), p.1263-1272
• Main Authors: Gokce, Ali, Hsiao, Kuang-Ting, Advani, Suresh G
• Format: Article
• Language: English
• Subjects: A. Polymer-matrix composites (PMCs); A. Preform; Applied sciences; Composites; E. Resin flow; E. Resin transfer molding (RTM); Exact sciences and technology; Forms of application and semi-finished materials; Optimization; Polymer industry, paints, wood; Technology of polymers
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/S1359-835X(02)00047-7

In liquid composite molding (LCM) processes the resin is injected into a mold cavity containing pre-placed reinforcement fabrics through openings known as gates, and the air leaves the mold through openings called as vents. The gate and vent locations play a crucial role as to whether the resin covers all empty spaces between the fibers in the mold, which dictates the quality and the properties of the final product. Optimization methods are used to find the gate and vent locations that will create a favorable flow that will prevent dry spots. In this paper, branch and bound search is adapted to mold filling in LCM processes and is used to find the optimal injection gate location that fulfill two different objectives. First, to find the gate locations that will yield the shortest fill time. Second, to find the auxiliary gate locations that will counteract a disturbance during filling and minimize the size of the dry spot. In each case, three geometries have been studied. The results are compared with exhaustive search and genetic algorithms results to illustrate the efficiency and accuracy of branch and bound search method.