کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
167950 1423394 2015 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
A dual-scale turbulence model for gas–liquid bubbly flows
ترجمه فارسی عنوان
یک مدل آشفتگی در مقیاس دوگانه برای گازا مایع حباب جریان دارد؟
کلمات کلیدی
دو مدل مایع، مدل آشفتگی در مقیاس دوگانه، آشفتگی ناشی از برش، آشفتگی ناشی از حباب، جریان حبابی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
چکیده انگلیسی

A dual-scale turbulence model is applied to simulate cocurrent upward gas–liquid bubbly flows and validated with available experimental data. In the model, liquid phase turbulence is split into shear-induced and bubble-induced turbulence. Single-phase standard k-ε model is used to compute shear-induced turbulence and another transport equation is added to model bubble-induced turbulence. In the latter transport equation, energy loss due to interface drag is the production term, and the characteristic length of bubble-induced turbulence, simply the bubble diameter in this work, is introduced to model the dissipation term. The simulated results agree well with experimental data of the test cases and it is demonstrated that the proposed dual-scale turbulence model outperforms other models. Analysis of the predicted turbulence shows that the main part of turbulent kinetic energy is the bubble-induced one while the shear-induced turbulent viscosity predominates within turbulent viscosity, especially at the pipe center. The underlying reason is the apparently different scales for the two kinds of turbulence production mechanisms: the shear-induced turbulence is on the scale of the whole pipe while the bubble-induced turbulence is on the scale of bubble diameter. Therefore, the model reflects the multi-scale phenomenon involved in gas–liquid bubbly flows.

Dual-scale turbulence generation mechanisms involved in gas–liquid bubbly flows: large-scale shear-induced and small-scale bubble-induced.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chinese Journal of Chemical Engineering - Volume 23, Issue 11, November 2015, Pages 1737–1745
نویسندگان
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