Influence of Mesh Discretization on the Prediction of Polymer Flow Behaviour in Microcavities

Abstract:

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Microinjection moulding is one of the key technologies for the mass production of plastics microcomponents. Recently, significant effort has been made to test the limits of applicability of existent numerical codes for simulating the polymer flow at the microscale. However, the modelling precision in what concerns polymer flow in microimpressions depends on factors which may not be properly accounted for in the process simulation. In this study, a micropart with variable thickness was designed, and the moulding block fabricated and instrumented. Short shots and complete filling of the cavity were carried out and the flow front progress was subsequently evaluated. These data were also assessed numerically by 3D-finite element modelling. A flow simulation considering the polymer as incompressible was carried out to investigate how the mesh size and density affected the prediction of the flow field in the microimpression, using the same processing conditions of the experimental study. The reduction of the mesh size as well as the increase of the mesh density are consistent with better representativeness of the experimental flow front progress in the microimpression. Moreover, the weld line prediction also tends to be improved. This study suggests that the mesh adaption and domain discretization is important in numerical studies of the polymer flow at the microscale.

Info:

Periodical:

Materials Science Forum (Volumes 730-732)

Edited by:

Ana Maria Pires Pinto and António Sérgio Pouzada

Pages:

525-530

DOI:

10.4028/www.scientific.net/MSF.730-732.525

Citation:

T. V. Zhiltsova et al., "Influence of Mesh Discretization on the Prediction of Polymer Flow Behaviour in Microcavities", Materials Science Forum, Vols. 730-732, pp. 525-530, 2013

Online since:

November 2012

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Price:

$38.00

[1] P. Mohren, M. Walter and G. Menges (Eds. ), How to Make Injection Moulds, Hanser Gardner Publications, Inc., Cincinnati, (2001) 106-107.

[2] Y. Donggang and K. Byung, Simulation of the filling process in micro channels for polymeric materials, Journal of Micromechanics and Microengineering 12 (2002) 604.

[3] C. -S. Chen, S. -C. Chen, W. -L. Liaw and R. -D. Chien, Rheological behavior of POM polymer melt flowing through micro-channels, European Polymer Journal 44 (2008) 1891-1898.

DOI: 10.1016/j.eurpolymj.2008.03.007

[4] C. Mnekbi, M. Vincent and J. Agassant, Polymer rheology at high shear rate for microinjection moulding, International Journal of Material Forming 3 (2010) 539-542.

DOI: 10.1007/s12289-010-0826-9

[5] J. G. Lee, B. K. Lee, T. G. Kang and T. H. Kwon, Experimental and numerical investigation of injection moulding with microrib patterns, Polymer Engineering & Science 50 (2010) 1186-1198.

DOI: 10.1002/pen.21642

[6] K. Dong Sung and et al., Micro-channel filling flow considering surface tension effect, Journal of Micromechanics and Microengineering 12 (2002) 236.

[7] L. Yu, L. J. Lee and K. W. Koelling, Flow and heat transfer simulation of injection moulding with microstructures, Polymer Engineering & Science 44 (2004) 1866-1876.

DOI: 10.1002/pen.20188

[8] T. Nguyen-Chung, G. Jüttner, C. Löser, T. Pham and M. Gehde, Determination of the heat transfer coefficient from short-shots studies and precise simulation of microinjection moulding, Polymer Engineering & Science 50 (2010) 165-173.

DOI: 10.1002/pen.21536

[9] D. Cardozo, Three Models of the 3D Filling Simulation for Injection Moulding: A Brief Review, Journal of Reinforced Plastics and Composites vol. 27 (2008) 1963-(1974).

DOI: 10.1177/0731684408092386

[10] J. C. Vasco, J. M. Maia and A. S. Pouzada, Thermo-rheological behaviour of polymer melts in microinjection moulding, Journal of Micromechanics and Microengineering 19 (2009).

DOI: 10.1088/0960-1317/19/10/105012

[11] D. Kazmer, Injection Mould Design Engineering, (2007): Cincinnati: Hanser Publishers; Hanser/Gardner Publications.

[12] L. Xie, G. Ziegmann, A visual mould with variotherm system for weld line study in micro injection moulding. Microsystem Technologies 14 (6) (2008) 809-814.

DOI: 10.1007/s00542-008-0566-7

[13] G. Tosello, A. Gava, H. N. Hansen, G. Lucchetta and F. Marinello, Characterization and analysis of weld lines on micro-injection moulded parts using atomic force microscopy (AFM), Wear 266 (2009) 534-538.

DOI: 10.1016/j.wear.2008.04.077

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