مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

شبیه‌سازی عددی هیدرودینامیک جریان دوفاز در سینی‌های غربالی برج تقطیر

نویسندگان
1 دانشجوی کارشناسی ارشد، مهندسی مکانیک، دانشگاه خواجه نصیرالدین طوسی، تهران
2 دانشگاه صنعتی خواجه نصیرالدین طوسی
چکیده
هدف از این پژوهش، بررسی پارامترهای هیدرولیکی موثر بر روی عملکرد برج تقطیر و مشخصات هیدرودینامیکی میدان جریان بر روی سینی غربالی در مقیاس صنعتی با استفاده از از شبیه‌سازی عددی می‌باشد. از روش دینامیک سیالات محاسباتی برای تحلیل و پیش‌بینی رفتار جریان بهره گرفته شد. هندسه مورد نظر، شامل فضای بین دو طبقه از برج تقطیر به همراه بخش ناودانی می‌باشد. پس از ترسیم هندسه و شبکه بندی آن در نرم افزار گمیبت، تحلیل میدان سه بعدی جریان به کمک نرم افزار فلوئنت شکل گرفت. از مدل دوفازی اویلری- اویلری برای شبیه‌سازی جریان دوفازی و مدل k-ε RNG جهت مدل‌سازی آشفتگی استفاده گردید. اعتبارسنجی نتایج، با استفاده از داده‌های آزمایشگاهی سولاری و بل و رابطه تجربی ارائه شده توسط کلول انجام شد. توزیع سرعت و کسر حجمی مایع و گاز در مکان های مختلف بر روی سینی و اطراف آن مشخص شد. اثر دبی حجمی ورودی مایع و گاز و هم‌چنین هندسه بند بر روی پارامترهای مرتبط با عملکرد سینی نظیر ارتفاع مایع زلال و ارتفاع ناحیه کف ‌مورد بررسی قرار گرفت. نتایج حاکی از آن بود که کاهش آشفتگی جریان گاز و مایع موجب بهبود عملکرد سینی‌های برج تقطیر خواهد شد.
کلیدواژه‌ها

عنوان مقاله English

Numerical Simulation of the Hydrodynamics of Two Phase Flow in Distillation Column Sieve Trays

نویسندگان English

Mehdi Ghiyasi 1
Mehrzad Shams 2
1 Department of Mechanical Engineering, Khaje Nasir Toosi University of Technology, Tehran, Iran.
2 Department of Mechanical Engineering, Khaje Nasir Toosi University of Technology, Tehran, Iran
چکیده English

The purpose of this research was to investigate the hydraulic parameters affecting the performance of the distillation column and the hydrodynamic characteristics of the flow field on the industrial scale-sieve tray using numerical simulation. Computational fluid dynamics method was used for analyzing and predicting flow behavior. The desired geometry including the space between two trays of the distillation column and the down comer region was considered. After plotting geometry, three dimensional grids were generated in Gambit software and the analysis of the flow field was traced in Fluent software. The Eulerian-Eulerian approach was applied to simulate two-phase flow and k-ε RNG model for turbulence modeling. Validation of the results was done successfully using Solari and Bell experiment data and the correlation presented by Colwell. The velocity distribution and volume fraction of liquid and gas in different zones were determined. The influence of inlet volumetric flow rate of liquid and gas, as well as the geometry of the weir, on parameters related to the tray performance such as clear liquid height and froth height were investigated. The results indicated that a better separation would occur in lower gas and liquid loads.

کلیدواژه‌ها English

Distillation Column
Sieve Tray
Clear Liquid Height
Computational Fluid Dynamics
Gas-Liquid Two phase Flow
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