Flow Process Analysis and Channel Structure Optimization of Laminator Based on VOF Model

doi:10.19491/j.issn.1001-9278.2020.05.011

Abstract

Abstract:

Based on the FLUENT software, the VOF model was adopted to study the changes of the melt delamination in the flow channel when the four?layer melt was multiplied to the eight?layer one by a laminator under different wall slip degrees and flow channel structure parameters. The analysis results indicated that the reduction of the degree of wall slip led to the accumulation of the melt on the upper and lower wall surfaces. This led to an increase in thickness of the melt layer at the upper and lower wall surfaces. The three structural parameters of fillet radius between the confluence section and the exit section, expansion angle of the confluence section and length of the equilibrium section only affected the accumulation of the melt on the left and right wall surfaces and therefore inflenced the dimensional accuracy of the melt in each layer. The influence of the angle was most signficant, followed by the length of equilibrium section. However, the influence was least from the radius of the fillet.

Key words: layer multiplier flow channel, volume of fluid model, structure optimization

CLC Number:

TQ320.6

Guo SONG, Yulu MA, Linsheng XIE, Huihao ZHU. Flow Process Analysis and Channel Structure Optimization of Laminator Based on VOF Model[J]. China Plastics, 2020, 34(5): 63-67.

Figures/Tables 10

Fig.1. Geometric model of the flow channel of the layer multiplier

流道	长度/mm	横截面尺寸/mm×mm
进口段	10	64×10
分流段	60	32×10
平衡段	0~40	32×10
汇流段	27.7~182.9	32×10~64×5
出口段	20	64×10

Tab.1. Length and cross section size of each channel of the layer multiplier

Fig.2. Finite element model of the flow channel of the layer multiplier

材料种类	零剪切黏度/Pa·s	松弛时间/s	幂律指数	密度/kg·m^-3
PP	5 500	0.3	0.6	910
PA6	8 900	0.2	0.5	1 140

Tab.2. Melt properties of PP and PA6

Fig.3. Melt distribution diagram at the inlet boundary

Fig.4. Distribution and average thickness of melt at each layer of outlet section under the condition of no slip on the wall

Fig.5. Effect of wall shear stress on the average thickness of bottom melt at outlet section

Fig.6. Effect of fillet radius on maximum thickness error the bottom melt at the outlet section（τ=673 Pa，L=40 mm，α=20 °）

Fig.7. Effect of equilibrium length on the maximum thickness error of the bottom melt at the outlet section（τ=673 Pa，R=20 mm，α=20 °）

Fig.8. Effect of divergence angle on the maximum thickness error of the bottom melt at the outlet section（τ=673 Pa，R=20 mm，L=20 mm）

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