آنالیز تشکیل قطره آب در روغن در کانال جریان هم‌محور به روش دینامیک سیالات محاسباتی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده مهندسی شیمی-دانشگاه صنعتی امیر کبیر- پردیس ماهشهر

2 عضو هیات علمی، دانشکده مهندسی شیمی، دانشگاه صنعتی امیرکبیر

چکیده

سیستم‌های دوفازی ابزاری مهم برای تشکیل قطرات محسوب می‌شوند که به دلیل کاربردهای متنوع در چند دهه اخیر بسیار مورد توجه قرار گرفته‌اند. در پژوهش حاضر، فرآیند تشکیل قطره‌ی آب در روغن در یک هندسه هم‌محور با استفاده از روش حجم سیال شبیه‌سازی می‌گردد و تأثیر پارامترهای مؤثر بر این فرآیند مانند سرعت و دانسیته فاز گسسته و همچنین کشش سطحی مورد بررسی قرار می‌گیرد. از نتایج حاصل برای تولید ذرات کروی گاما-آلومینا به روش قطره‌ی روغن استفاده می‌شود. در این پژوهش با ساخت یک سامانه آزمایشگاهی، عوامل مؤثر بر فرآیند تشکیل قطره بررسی گردد. نتایج عددی با داده‌های آزمایشگاهی اعتبارسنجی شده است. خطای اندازه‌گیری برای اندازه قطره حدود 5% و برای کرویت حدود 4% است. مطالعات نشان می‌دهد که اگر چه پارامترهای ذکر شده تأثیر زیادی روی اندازه قطرات و زمان جدایش دارند اما وابستگی اندازه قطرات به کشش سطحی و دانسیته فاز گسسته بیشتر است. افزایش کشش ‌سطحی موجب افزایش اندازه قطرات و زمان جدایش می‌شود. همچنین، با افزایش دانسیته فاز گسسته، اندازه قطرات کاهش اما زمان جدایش افزایش یافته است. افزایش سرعت نیز با وجود تأثیر ناچیز، منجر به افزایش اندازه و کاهش زمان جدایش قطرات شده است.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Computational Fluid Dynamics Analysis of Water-in-Oil Droplet Formation within a Co-Flow Channel

نویسندگان [English]

  • Foruzan Rostami 1
  • Mohammad Rahmani 2
1 Chemical Enginering Department Amirkabir University Tecnology Mahshahr Campus
2 Faculty member, Chemical Engineering department, Amirkabir University of Technology
چکیده [English]

Two-phase systems are important tools for droplet formation that have received much attention in recent decades due to their vast applications. In the present work, the process of water-in-oil droplet formation, in a coaxial geometry using the fluid volume method, and the impact of effective parameters such as dispersed phase velocity and density and also interfacial tension are investigated. The results are used to produce spherical γ-alumina particles by the oil drop method. In this study, using a laboratory setup, the factors affecting the droplet formation process are investigated. Results are validated against laboratory data. The measurement error is about 5% for droplet size and about 4% for sphericity. Studies show that although the mentioned parameters have a great effect on droplet size and separation time, the dependency of droplets diameter on interfacial tension and dispersed phase density is higher. Increasing the interfacial tension causes increasing droplets size and separation time. Also increasing the density of the dispersed phase reduces the diameter of the droplets and increases separation time. Increasing the velocity also had a small effect, but lead to an increase in size and reduced droplets separation time.

کلیدواژه‌ها [English]

  • Droplet formation
  • Two-phase flow
  • Co-flow channel
  • Volume of fluid method
  • Computational fluid dynamics

مراجع

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نشریه مهندسی مکانیک امیرکبیر
دوره 54، شماره 5
مرداد 1401
صفحه 1029-1046

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