Numerical Simulation on Melt Flow Characteristics of UHMWPE in Eccentric Rotor Extruder

doi:10.12141/j.issn.1000-565X.220528

Abstract

Abstract:

The processing difficulties of UHMWPE caused by the wall slip can be solved effectively by the eccentric rotor extruder, which make the melt conveyed in positive displacement. To reveal the melt flow characteristics of UHMWPE in the conveying section of the eccentric rotor extruder, the model parameters of wall slip were determined by the combination of experiment and numerical simulation, and the flow field of UHMWPE melt was numerically simulated by ANSYS Polyflow. The results show that the UHMWPE melt in the cavity formed by the meshing of the rotor and the stator can be conveyed in positive displacement, and the change in the cross-sectional size of the cavity leads to the elongation flow field in the melt. When the meshing gap exists, the positive pressure and negative pressure formed around every inlet and outlet respectively, will lead to the counterflow and leakage of the melt in the cavity and make the average flow rate at the outlet of the cavity lower than the theoretical flow rate. When UHMWPE is processed by the eccentric rotor extruder, the instantaneous flow rate and average flow rate of the melt at the outlet of the cavity are proportional to the rotor rotation speed, while the pulsation rate of the flow rate remains unchanged. Reducing the meshing gap between the rotor and the stator increases the average flow rate of the melt at the outlet of the cavity and decreases the pulsation rate of the flow rate, which enhances the positive displacement conveying of the melt in the eccentric rotor extruder.

Key words: UHMWPE, eccentric rotor extruder, wall slip, positive displacement conveying, numerical simulation

CLC Number:

TQ320.66

MA Xiangjun, WANG Zhen, YAO Zhiqiang, et al. Numerical Simulation on Melt Flow Characteristics of UHMWPE in Eccentric Rotor Extruder[J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(5): 114-121.

Figures/Tables 15

Fig.1

Fig.2

Fig.3

Fig.4

Fig.5

Table 1

Fig.6

Fig.7

Fig.8

Fig.9

Fig.10

Fig.11

Table 2

Fig.12

Table 3

References 15

1	FU J， JIN Z， WANG J ．UHMWPE biomaterials for joint implants ［M］．Singapore：Springer Singapore，2019.
2	MIRSALEHI S A， KHAVANDI A， MIRDAMADI S，et al ．Nanomechanical and tribological behavior of hydroxyapatite reinforced ultrahigh molecular weight polyethylene nanocomposites for biomedical applications ［J］．Journal of Applied Polymer Science，2015，132（23）：1-11.
3	EDIDIN A A， KURTZ S M ．Influence of mechanical behavior on the wear of 4 clinically relevant polymeric biomaterials in a hip simulator ［J］．The Journal of Arthroplasty，2000，15（3）：321-331.
4	QU J， ZHANG G， YIN X ．Volume pulsed deformation plasticating and conveying method and device by eccentric rotor：US 15310907 ［P］．2017-03-23.
5	FENG Y， GAO Y， CHEN J，et al ．Properties of compression molded ultra-high molecular weight polyethylene products pretreated by eccentric rotor extrusion ［J］．Polymer International，2019，68（5）：862-870.
6	CHEN R， LIU X， HAN L，et al ．Morphology，thermal behavior，rheological，and mechanical properties of polypropy-lene/polystyrene blends based on elongation flow ［J］．Polymers for Advanced Technologies，2020，31（11）：2722-2732.
7	WU T， HUANG Z， WANG D，et al ．Effect of continuous elongational flow on structure and properties of short glass fiber reinforced polyamide 6 composites ［J］．Advanced Industrial and Engineering Polymer Research，2019，2（3）：93-101.
8	WU T， TONG Y， QIU F，et al ．Morphology，rheology property，and crystallization behavior of PLLA/OMMT nanocomposites prepared by an innovative eccentric rotor extruder ［J］．Polymers for Advanced Technologies，2018，29（1）：41-51.
9	CAO C， CHEN X， WANG J，et al ．Structure and properties of ultrahigh molecular weight polyethylene processed under a consecutive elongational flow ［J］．Journal of Polymer Research，2018，25（1）：1-9.
10	袁丁．偏心转子挤出机熔体输运的拉伸形变作用研究［D］．广州：华南理工大学，2018.
11	FAN D， YANG M， HUANG Z，et al ．Numerical simulation of mixing characteristics in the eccentric rotor extruder with different process conditions and structural parameters ［J］．Advances in Polymer Technology，2019，2019（2）：1-11.
12	WEN J， YANG M， FAN D ．Numerical simulation of energy consumption in the melt conveying section of eccentric rotor extruders ［J］．Advances in Polymer Technology，2018，37（8）：3335-3347.
13	Inc Ansys ．ANSYS polyflow users’ guide ［Z］．Canonsburg：Ansys Inc.，2021：573-592.
14	Inc Ansys ．ANSYS polyflow example manual ［Z］．Canonsburg：Ansys Inc.，2021 ：Example 38/1-9.
15	尹晨欢．偏心转子挤出机熔体输送段流场的数值模拟［D］．广州：华南理工大学，2018.

Q_i /（mm³·s^-1）	$Δ p i$ /MPa	$Δ p i'$ /MPa	相对误差/%
678	14.20	13.99	1.48
1 027	15.30	15.70	2.61
1 368	16.30	16.48	1.10
1 671	17.20	16.87	1.92

转速/（r·min^-1）	流率/（mm³·s^-1）			流率脉动率/%
转速/（r·min^-1）	最大值	最小值	平均值	流率脉动率/%
20	12 487	11 598	11 889	7.47
30	18 748	17 390	17 833	7.62
40	25 024	23 184	23 804	7.77

啮合间隙/mm	流率/（mm³·s^-1）			流率脉动率/%
啮合间隙/mm	最大值	最小值	平均值	流率脉动率/%
0.2	19 911	18 875	19 199	5.39
0.3	18 748	17 390	17 833	7.62
0.4	16 355	14 654	15 154	11.24

[1]	YU Mingquan, ZHAO Jiyun, MAN Jiaxiang, et al.. Study of Distribution Structure for High Water-Based Hydraulic Motor [J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(9): 19-29.
[2]	LU Zhimin, LI Bohang, TANG Wen, et al. Optimization Simulation of Ammonia Injection in SCR DeNO _x System of Coal-Fired Power Plant [J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(8): 62-70.
[3]	LIU Dingping, ZHANG Xiangyang, CHEN Aihua, et al. Numerical Analysis of Performance of Cyclone-Tube Demister Based on Orthogonal Design [J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(6): 89-96.
[4]	DAI Gonglian, CHEN Kun, GE Hao, et al. Research on Numerical Simulation of Rail Non-contact Nondestructive Testing Technology [J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(4): 44-52.
[5]	LI Shuxun, HU Yinggang, LI Cheng, et al. Optimization of Body Profile Line of Axial Flow Control Valve Based on Surrogate Model [J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(3): 41-52.
[6]	TIAN Lifeng, GUO Meiqi, DING Hao, et al. On Aero-optical Effect and Control of Supersonic Boundary Layer [J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(2): 137-146.
[7]	YU Mingquan, ZHAO Jiyun, MAN Jiaxiang, et al.. Study on Flow Distribution Mechanism of Low Speed High Torque Hydraulic Motor [J]. Journal of South China University of Technology(Natural Science Edition), 2023, 51(11): 101-109.
[8]	DU Jianming, FANG Qian , WANG Gan, et al. Characteristics of Transient Pressure and Pressure Gradient of a High-Speed Train Travelling Through a Double-Track Tunnel [J]. Journal of South China University of Technology(Natural Science Edition), 2022, 50(9): 58-68.
[9]	GONG Nan, LI Peizhen, HE Xuming. Design of an Innovative Eddy Current Replaceable Coupling Beam and Its Numerical Analysis [J]. Journal of South China University of Technology(Natural Science Edition), 2022, 50(7): 25-34.
[10]	DU Jianming, FANG Qian, LI Jianye. Influences of Train to Tunnel Area Ratio on Aerodynamic Pressure Characteristics of High-Speed Railway Tunnel Wall [J]. Journal of South China University of Technology(Natural Science Edition), 2022, 50(5): 56-64.
[11]	YANG Chen, WANG Fenglei, WU Jiayi, et al. Analysis of Shell-Side Thermal-Hydraulic Performance of Hybrid Smooth and Spirally Corrugated Tubes [J]. Journal of South China University of Technology(Natural Science Edition), 2022, 50(2): 137-144.
[12]	HUANG Si, ZHANG Guoran, TANG Zirui, et al. Fluid-Solid Coupling Analysis of Spherical Storage Tank under Wind Load [J]. Journal of South China University of Technology(Natural Science Edition), 2022, 50(2): 67-75.
[13]	LIN Tao, LIAO Yanfen, YANG Xucong, et al. Structure Optimization of 350 t/d Waste Incinerator [J]. Journal of South China University of Technology (Natural Science Edition), 2021, 49(7): 116-124.
[14]	YANG Song, LI Wenqiang, HUANG Xu, et al. Study on Temperature Field of Steel Box Girder Based on Modified Convective Heat Transfer Coefficient [J]. Journal of South China University of Technology(Natural Science Edition), 2021, 49(4): 47-58,64.
[15]	LIAO Yanfen, ZHANG Manyu, CHEN Shunkai, et al. Study on MILD Combustion of MSW Pyrolysis Gas Based on FLUENT [J]. Journal of South China University of Technology (Natural Science Edition), 2021, 49(2): 9-16.