نوع مقاله : مقاله پژوهشی
نویسندگان
1 دکتری سازه‌های آبی، گروه علوم و مهندسی آب، دانشگاه تبریز، تبریز، ایران
2 دانشجوی دکتری آبیاری و زهکشی، گروه علوم و مهندسی آب، دانشگاه صنعتی اصفهان، اصفهان، ایران
چکیده
سرریزها عموماً برای انحراف جریان، عبور سیل، کنترل سطح آب در سدها، رودخانه ها و مجاری روباز به کار گرفته میشوند. سرریز کرامپ با طراحی خاص خود، جزو سرریزهای لبه کوتاه است و جهت اندازه گیری دبی عبوری کانالها مورد استفاده قرار میگیرد. در مطالعه حاضر، ضریب دبی جریان بر روی سرریز کرامپ با استفاده از نرمافزار FLUENT به ازای شیب ها و ارتفاع های مختلف مدل‌سازی شد. میدان جریان بر روی سرریز کرامپ با استفاده از سه مدل آشفتگیRSM ، k-ε RNG و k-ω به‌صورت دو بعدی و مدل چند فازی VOF انجام شد. شرایط جریان در تمامی حالات به‌صورت زیربحرانی، آشفته و جریان ریزشی در نظر گرفته شد. کارایی نرمافزار FLUENT با استفاده از شاخص‌های آماری، شامل ضریب تببین (R2)، میانگین مربعات خطا (RMSE) و میانگین مطلق خطا (MAE) مورد ارزیابی قرار گرفت. نتایج بیانگر آن است که نرمافزار FLUENT با کسب مقادیر 0/93=RMSE و 0/7=MAE کارایی مناسبی در مدل‌سازی جریان بر روی سرریز کرامپ دارد. نتایج نشان داد با افزایش ارتفاع سرریز در یک دبی ثابت، ضریب دبی کاهش مییابد. ضریب دبی در سرریز کرامپ با ارتفاع 0/15 متر بیش‌ترین مقدار را دارا بود. رابطه مستقیمی با افزایش شیب دیواره پایین دست سرریز و ضریب دبی جریان وجود دارد، به‌طوری‌که با افزایش شیب دیواره، ضریب دبی جریان نیز افزایش مییابد.
کلیدواژه‌ها
عنوان مقاله [English]
An Intelligent Method for Numerical Simulation of Flow Over Crump Weir Based on Computational Fluid Dynamics
نویسندگان [English]
- Somayeh Emami 1
- Omid Jahandideh 2
1 Ph.D. in Hydraulic Structures, Department of Water Engineering, University of Tabriz, Tabriz, Iran
2 Ph.D Student of Irrigation and Drainage, Department of Water Science and Engineering, Isfahan University of Technology, Isfahan, Iran
چکیده [English]
Weirs are generally used for flow diversion, flood passage, and water level control in dam reservoirs, rivers, and open channels. The Crump weir with its special design is one of the short-edge weirs, which is used to measure the discharge of channels. In the present study, the discharge coefficient on the Crump weir was modeled using FLUENT software for different slopes and heights. The flow field on the Crump weir was performed using three turbulence models RSM, k-ε RNG, and k-ω in two dimensions and a multiphase VOF model. The flow conditions were considered as subcritical, turbulent, and falling flow in all cases. The efficiency of FLUENT software was evaluated using statistical indicators, including correlation coefficient (R2), root mean square error (RMSE), and mean absolute error (MAE). The results show that the FLUENT software has good efficiency in modeling the flow on the crump weir by obtaining RMSE=0.93 and MAE=0.7. The results showed that with the increase of the weir height at a constant discharge, the discharge coefficient decreases. The discharge coefficient in the Crump weir with a height of 0.15m had the highest value. There is a direct relationship between the increase in the downstream wall slope of the weir and the discharge coefficient so with the increase in the downstream wall slope, the discharge coefficient increases.
کلیدواژه‌ها [English]
- Crump weir
- Discharge coefficient
- Turbulence models
- FLUENT
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