Numerical simulation on residual thickness of pipes with curved sections in water-assisted co-injection molding

• Published in: Journal of applied polymer science Vol. 132; no. 34; pp. np - n/a
• Main Authors: Kuang, Tang-Qing, Xu, Bai-Ping, Zhou, Guo-Fa, Turng, Lih-Sheng
• Format: Journal Article
• Language: English
• Published: Hoboken Blackwell Publishing Ltd 10.09.2015; Wiley Subscription Services, Inc
• Subjects: Bending; Computational fluid dynamics; Computer simulation; Curved; manufacturing; Materials science; Mathematical models; Melts; Molding (process); Polymers; Process parameters; theory and modeling; thermoplastics
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.42468

ABSTRACT The residual thicknesses of the skin and the inner layers are important quality indicators of water‐assisted co‐injection molding (WACIM) process or overflow WACIM (O‐WACIM) parts. At the curved section, the residual thicknesses change significantly. A numerical simulation program based on the computational fluid dynamics method was developed to simulate the O‐WACIM process. After the numerical simulation program was validated with the experimental results, it was used to study the effects of the bending radii and bending angles on the residual thicknesses of the skin and inner layers of O‐WACIM parts. The results showed that the penetration of the inner melt and water was always close to the inner concave side due to the higher local pressure gradient and temperature. The effects of processing parameters on the residual thicknesses of the skin and inner layers were investigated using the orthogonal simulation method. It was found that the residual thicknesses of the skin/inner layer at the inner concave/outer convex side are mainly influenced by different parameters. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42468.