Improving mixing characteristics with a pitched tip in kneading elements in twin-screw extrusion

Yasuya Nakayama, Hiroki Takemitsu, Toshihisa Kajiwara, Koichi Kimura, Takahide Takeuchi, Hideki Tomiyama

研究成果: ジャーナルへの寄稿記事

2 引用 (Scopus)

抄録

In twin-screw extrusion, the geometry of a mixing element mainly determines the basic flow pattern, which eventually affects the mixing ability as well as the dispersive ability of the mixing element. The effects of geometrical modification, with both forward and backward pitched tips, of a conventional forward kneading disks element (FKD) in the pitched-tip kneading disks element on the flow pattern and mixing characteristics are discussed. Numerical simulations of fully filled, nonisothermal polymer melt flow in the melt-mixing zone were performed, and the flow pattern structure and the tracer trajectories were investigated. The pitched tips largely affect the inter-disk fluid transport, which is mainly responsible for mixing. These changes in the local flow pattern are analyzed by the distribution of the strain-rate state. The distribution of the finite-time Lyapunov exponent reveals a large inhomogeneity of the mixing in FKD is suppressed both by the forward and backward tips. By the forward tips on FKD, the mixing ability is relatively suppressed compared to FKD, whereas for the backward tips on FKD, the mixing ability is enhanced while maintaining the same level of dispersion efficiency as FKD. From these results, the pitched tips on the conventional KD turn out to be effective at reducing the inhomogeneity of the mixing and tuning the overall mixing performance.

元の言語英語
ページ(範囲)1424-1434
ページ数11
ジャーナルAIChE Journal
64
発行部数4
DOI
出版物ステータス出版済み - 4 2018

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Extrusion
Polymers
Flow patterns
Filled polymers
Polymer melts
Strain rate
Tuning
Trajectories
Fluids
Geometry
Computer simulation

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Environmental Engineering
  • Chemical Engineering(all)

これを引用

Improving mixing characteristics with a pitched tip in kneading elements in twin-screw extrusion. / Nakayama, Yasuya; Takemitsu, Hiroki; Kajiwara, Toshihisa; Kimura, Koichi; Takeuchi, Takahide; Tomiyama, Hideki.

:: AIChE Journal, 巻 64, 番号 4, 04.2018, p. 1424-1434.

研究成果: ジャーナルへの寄稿記事

Nakayama, Yasuya ; Takemitsu, Hiroki ; Kajiwara, Toshihisa ; Kimura, Koichi ; Takeuchi, Takahide ; Tomiyama, Hideki. / Improving mixing characteristics with a pitched tip in kneading elements in twin-screw extrusion. :: AIChE Journal. 2018 ; 巻 64, 番号 4. pp. 1424-1434.
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