شبیه‌سازی عددی هیدرودینامیک جریان‌ چند فازی گاز-جامد در بستر دوار: تأثیر ضریب ارتجاعی بر ضخامت لایه فعال

نوع مقاله : ترویجی

نویسندگان

1 کارشناسی ارشد مهندسی شیمی، آزمایشگاه تحقیقاتی دینامیک سیالات محاسباتی (CFD)، دانشکده مهندسی شیمی، دانشگاه علم و صنعت ایران

2 دانشیار، آزمایشگاه تحقیقاتی دینامیک سیالات محاسباتی (CFD)، دانشکده مهندسی شیمی، دانشگاه علم و صنعت ایران

چکیده

در مطالعه حاضر به شبیه‌سازی دوبعدی هیدرودینامیک بستر گاز - جامد دوار در رژیم غلتان به‌منظور استفاده در پیرولیز ضایعات پلیمری پرداخته شده است. مدل‌سازی با رویکرد اولرین - اولرین به همراه نظریه جنبشی جریان‌های دانه‌ای انجام شده است. نتایج حاصل از شبیه‌سازی با کار آزمایشگاهی انجام شده در بستر دوار توسط سانتوس و همکاران (2015) مقایسه شد که حاکی از انطباق خوب نتایج با کارهای آزمایشگاهی بوده است. در این پژوهش به بررسی تأثیر پارامتر ضریب ارتجاعی بر ضخامت لایه فعال پرداخته شده است. بدین منظور مقادیر مختلف ضریب ارتجاعی (0/85، 0/9، 0/92 و 0/95) انتخاب شده و تأثیر آن بر ضخامت لایه فعال در بستر دوار بررسی شده است. با افزایش ضریب ارتجاعی از 0/85 تا 0/95 میزان ضخامت لایه فعال افزایش یافته که با توجه به اینکه بخش اصلی اختلاط در بسترهای دوار صورت می‌گیرد، می‌توان تأثیر آن در بهبود اختلاط در بسترهای دوار را با در نتایج مشاهده کرد.

کلیدواژه‌ها


عنوان مقاله [English]

Numerical Simulation of Multi-Phase Flow Hydrodynamic in Rotating Drum: Effect of Restitution Coefficient on Active Layer Thickness

نویسندگان [English]

  • afshin taghizade 1
  • Seyed Hassan Hashemabadi 2
1 Msc. in Chemical Engineering, Computational Fluid Dynamics (CFD) Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology (IUST), Tehran, Iran
2 Professor Associated of Computational Fluid Dynamics (CFD) Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology (IUST), Tehran, Iran
چکیده [English]

A two-dimensional hydrodynamic simulation of two-phase flow in a rotating drum under rolling conditions was examined in this study. The Eulerian-Eulerian multi-phase approach was utilized in this study to model the gas-solid system in a rotating drum, combined with the kinetic theory of granular flow. The results of these simulation was verified with experimental data was reported with Santos et al. (2015) which indicates that the results are consistent with experimental work. In this study impact of restitution coefficient on active layer thickness was investigated. For this purpose the restitution value set to different values (0.85, 0.9, 0.92, and 0.95) and their effect on the thickness of active layer on the rotating drum was examined. The thickness of the active layer was increased by raising the coefficient of restitution from 0.85 to 0.95, which, given that the majority of mixing occurs in rotating beds, can demonstrate an improvement in the degree of mixing in rotating beds with the results.

کلیدواژه‌ها [English]

  • Rotating Bed
  • Hydrodynamic
  • numerical simulation
  • Restitution Coefficient
  • Active Layer
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