شبیه‌سازی هیدرودینامیکی قطرات استخراج مایع- مایع و تأثیر انتقال جرم بر هیدرودینامیک

نوع مقاله: مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی شیمی، نفت وگاز، آزمایشگاه طراحی فرآیند به کمک کامپیوتر، دانشگاه علم و صنعت ایران

2 دانشکده مهندسی شیمی، نفت وگاز، آزمایشگاه جداسازی، دانشگاه علم و صنعت ایران

چکیده

شبیه‌سازی هیدرودینامیکی و انتقال جرمی قطره تولوئن بالارونده در سیال ساکن آب مورد بررسی قرار گرفت. برای شبیه‌سازی هیدرودینامیکی از روش حجم سیال با مدل کشش سطحی CSSو روش PLIC استفاده شد. قطرات در سه رژیم کروی، چرخشی و نوسانی شبیه‌سازی شدند و همخوانی بسیار خوب با نتایج تجربی با میانگین خطای 63/3% به‌دست آمد. همچنین مدل هیدرودینامیکی تحقیق حاضر توانست رژیم نوسانی قطره را در قطر mm 4/4 و قطر قطره با سرعت بیشینه را در قطر mm 5/3 پیش‌بینی نماید که دارای همخوانی بسیار خوب با نتایج تجربی بود. در گام بعدی شبیه‌سازی، به‌منظور تأثیر انتقال جرم در سرعت قطرات تولوئن mm 2، معادلات انتقال جرمی به شبیه‌سازی‌ها اضافه شد. تمامی خواص سیال در شبیه‌سازی‌ها به‌ غیر از کشش سطحی ثابت نظر گرفته شد. نتایج شبیه‌سازی نشان داد بدون در نظر گرفتن تابعیت کشش سطحی با غلظت، سرعت شبیه‌سازی‌شده با نتایج تجربی موجود در مقالات دارای میانگین خطای 83% بود که با درنظرگرفتن آن میزان خطا تا حدود 2% کاهش یافت. گزارش خطوط جریان، شکل قطرات، سرعت محوری و سرعت حدی از نتایج دیگر این تحقیق است.
 

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Hydrodynamic Simulation of Liquid-Liquid Extraction Drops and the Effect of Mass Transfer on the Hydrodynamics

نویسندگان [English]

  • Sepideh Roshdi 1
  • Norolah Kasiri 1
  • Ahmad Rahbar-Kelishami 2
1 Computer Aided Process Engineering Center, School of Chemical Oil and Gas Engineering, Iran University of Science and Technology, Tehran, Iran
2 School of Chemical Oil and Gas Engineering, Iran University of Science and Technology (IUST), Tehran, Iran
چکیده [English]

Hydrodynamic and mass transfer simulations of toluene rising drops have been investigated. The VOF-PLIC method with surface tension model of CSS was applied. Drops have been simulated in the three regimes of spherical, circulating, and oscillating regimes. Simulation results agreed well with existing experimental data with the average relative error of 3.63 percent. The current hydrodynamic model predicted the oscillating regime for the drop diameter of 4.4 mm and 3.5 mm drops were identified as the drops with maximum velocity. These findings agreed well with existing experimental data. In the next step of simulations, mass transfer equation was supplemented into the simulations investigating mass transfer effect on the velocity of 2 mm toluene drops. All of the properties of drops were assumed constant except surface tension coefficient. Simulation results showed that, with the assumption of concentration dependent surface tension coefficient, terminal velocity relative error was about 2 percent, while without considering of that, relative error increased to 83 percent. Streamlines, drop shapes, axial velocity, and terminal velocity were also reported.
 

کلیدواژه‌ها [English]

  • Numerical Simulation
  • VOF Model
  • Liquid-Liquid Extraction
  • Mass Transfer
  • Hydrodynamics

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