Numerical Investigation of Internal Flow Transition Using Modified γ-Reθ Model
Author(s):
Article Type:
Research/Original Article (دارای رتبه معتبر)
Abstract:
The numerical investigation of Transition is one of the challenging issues in turbulence modeling. In the present study, the coefficients of the γ-Reθ model are modified based on the physics of internal flow transition to capture the entrance length properly. To validate the model, the internal flow is simulated using six test cases. A 3D duct, two smooth axisymmetric pipes, a 3D stenosis pipe, two parallel plates, and the backward-facing step configurations are considered at different Reynolds numbers from 2´103 to 3´105. The flow variables, including the average velocity field, friction factor, fully developed friction factor, and the reattachment length are compared against the experimental, theoretical and large eddy simulation results. By comparing the results of average velocity against the semi-empirical relations and experimental data using new coefficients, it is observed the model can estimate the entrance length in accordance with experiments. The earlier coefficients lead to a reduction of entrance length by increasing the Reynolds number. Furthermore, the error percentages reduce by more than 7.6 and 26.7 percent using new coefficients rather than earlier models for fully developed friction factor and reattachment length, respectively.
Keywords:
Language:
Persian
Published:
Amirkabir Journal Mechanical Engineering, Volume:54 Issue: 7, 2022
Pages:
1533 to 1552
magiran.com/p2724358
دانلود و مطالعه متن این مقاله با یکی از روشهای زیر امکان پذیر است:
اشتراک شخصی
با عضویت و پرداخت آنلاین حق اشتراک یکساله به مبلغ 1,390,000ريال میتوانید 70 عنوان مطلب دانلود کنید!
اشتراک سازمانی
به کتابخانه دانشگاه یا محل کار خود پیشنهاد کنید تا اشتراک سازمانی این پایگاه را برای دسترسی نامحدود همه کاربران به متن مطالب تهیه نمایند!
توجه!
- حق عضویت دریافتی صرف حمایت از نشریات عضو و نگهداری، تکمیل و توسعه مگیران میشود.
- پرداخت حق اشتراک و دانلود مقالات اجازه بازنشر آن در سایر رسانههای چاپی و دیجیتال را به کاربر نمیدهد.
In order to view content subscription is required
Personal subscription
Subscribe magiran.com for 70 € euros via PayPal and download 70 articles during a year.
Organization subscription
Please contact us to subscribe your university or library for unlimited access!