Numerical simulation of flow process of pellets in underwater⁃pelletizing device based on CFD⁃DEM

doi:10.19491/j.issn.1001-9278.2022.06.014

Abstract

Abstract:

Based on the CFD?DEM coupling method， the flow state of particles in the water chamber in an underwater?pelletizing device was studied， and the effects of the cutter shaft speed， inflow rate of the particle water， and chamber outlet angle on the palletizing process were analyzed. The results indicated that the discharge of particles in the water chamber could be enhanced by increasing the cutter shaft speed， inflow rate of the particle water， and chamber outlet angle. Furthermore， there was a separation angle between the pellets and polymer crumbs at the chamber outlet. The research results obtained in this paper can provide theoretical guidance for in?depth analysis of the working principle of underwater pelletizing device.

Key words: underwater pelletizing, CFD?DEM coupling method, water chamber, numerical simulation, particle flow

CLC Number:

TQ320.66

ZHANG Qingtao, BI Chao. Numerical simulation of flow process of pellets in underwater⁃pelletizing device based on CFD⁃DEM[J]. China Plastics, 2022, 36(6): 87-91.

Figures/Tables 12

Fig.1. Geometric model of pelletizing water chamber

Fig.2. Grid division of water chamber model

参数

壁面

颗粒

泊松比

剪切模量/Pa

密度/kg•m^⁃3

复原系数

静摩擦因数

动摩擦因数

0.3

7.923×10¹¹

7 800

0.5

0.2

0.01

0.41

3×10⁸

918

0.5

0.3

0.01

Tab.1. DEM parameters

Fig.3. Velocity vector distribution at the middle plane of inlet and outlet of the water chamber

Fig.4. Particle flow state in the water chamber

Fig.5. Effect of cutter head speed on the quality of retained particles

Fig.6. Effect of cutter head speed on average residence time of the particles

Fig.7. Effect of the particle water flux on the number of retained particles

Fig.8. Effect of particle water flux on the particle average residence time

Fig.9. Effect of outlet angle of the water chamber on the number of retained particles

Fig.10. Effect of outlet angle on average residence time of the particles

Fig.11. Particle size distribution at the outlet

References 10

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