بررسی عددی تأثیر پارامترهای هندسی سرریز جانبی با پلان ذوزنقه‌ای بر ضریب دبی جریان

نویسندگان

1 دانشجوی دکتری دانشگاه ارومیه

2 دانشگاه تبریز

3 گروه مهندسی اب دانشگاه تبریز

4 گروه مهندسی آب، دانشکده کشاورزی، دانشگاه تبریز

10.22034/ws.2024.59395.2544

چکیده

سرریزها از مهم‌ترین سازه‌های اندازه گیری و تنظیم دبی جریان هستند. همچنین سازه‌های هیدرولیکی ساده‌ای هستند که به منظور کنترل سطح آب و اندازه گیری شدت جریان در کانال‌ها مورد استفاده قرار می‌گیرند. سرریزهای جانبی گاه باعنوان سرریز کناری هم شناخته می‌شوند. سرریزهای جانبی معمولاً به شکلهای هندسی مختلف از جمله مستطیلی، قوسی، ذوزنقه‌ای و مثلثی ساخته می‌شوند. در سرریزهای جانبی ذوزنقه‌ای شکل ارتفاع سرریز، بار آبی، زاویه دیواره سرریز بر روی ضریب دبی جریان تأثیر دارد. در این تحقیق به‌صورت عددی با استفاده از نرم‌افزار فلوئنت تأثیر پارامترهای زاویه رأس دیواره ی سرریز، ارتفاع سرریز و بار آبی بر روی ضریب‌دبی سرریز جانبی ذوزنقه‌ای مورد بررسی قرار گرفت و نتایج به‌دست آمده با نتایج حاصل از داده‌های آزمایشگاهی مقایسه گردید. نتایج حاصل از شبیه‌سازی، بسیار نزدیک به نتایج آزمایشگاهی به‌دست آمد. مقادیر خطای نسبی در بازه 5 تا 7 درصد به دست امد. با توجه به این نتایج، مقادیر ضریب‌دبی آزمایشگاهی با مقادیر شبیه‌سازی شده تطابق خوبی دارد. ضریب‌دبی وابسته به یک پارامتر هیدرولیکی و یا هندسی نبوده بلکه پارامترهای ارتفاع نسبی سرریز، بار آبی، زاویه رأس دیواره سرریز بر آن تأثیر گذارند. همچنین نتایج به دست آمده نشان داد که، سرریز جانبی با شیب دیواره 45 درجه نتایج بهتری در مقایسه با دو زاویه مورد بررسی دیگر دارد، چون دارای بیشترین مقدار ضریب دبی در بین سرریزهای مختلف است. همچنین می توان نتیجه گرفت مقادیر سرعت در نزدیک سرریز جانبی با شیب بیش‌تری کاهش می‌یابد و به طرف پایین دست در کانال اصلی تغییرات سرعت کاهش می یابد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical investigating the effect of Trapezoidal sharp-crested sideweir geometric parameters on discharge coefficient

نویسندگان [English]

  • sara namdar 1
  • akram abbaspour 2
  • Ali Hosseinzadeh 3
  • Farzin Salmasi 4
1 PhD student
2 University of Tabriz
3 water Eng. University of Tabriz
4 University of Tabriz, Agricultural faculty, Department of water engineering
چکیده [English]

Weirs are one of the most important structures for measuring and regulating flow rate. They are also simple hydraulic structures used to control the water level and measure the flow rate in canals. Lateral weirs are sometimes known as side weirs. Side weirs are usually made in various geometric shapes such as rectangular, arched, trapezoidal and triangular. In trapezoidal side weirs, weir height, hydraulic head, and weir wall angle affect the discharge coefficient. In this research, the effect of the mentioned parameters on the discharge coefficient, hydraulic characteristics of the flow including flow rate, the water surface profile and energy variations were investigated numerically. The result of this research was presented by a nonlinear equation. In this study, the effect of weir wall angle, weir height and hydraulic head on the discharge coefficient of trapezoidal side weirs was investigated numerically using FLUENT software and also the numerical results were compared with the experimental data. The results of the simulation were in a good agreement with the experimental data . The flow coefficient (Cm) does not depend on several hydraulic and geometric parameters. The results also showed that the side weir with a wall slope of z = 1 has better performance compared to the other two angles. Because it has the highest amount of the discharge coefficient among different overflow heights. Also, the velocity decreases with a greater slope near the side overflow. It can be concluded that the lower the overflow height, the greater the depth velocity changes will be compared to other models under different wall slopes
Weirs are one of the most important structures for measuring and regulating flow rate. They are also simple hydraulic structures used to control the water level and measure the flow rate in canals. Lateral weirs are sometimes known as side weirs. Side weirs are usually made in various geometric shapes such as rectangular, arched, trapezoidal and triangular. In trapezoidal side weirs, weir height, hydraulic head, and weir wall angle affect the discharge coefficient. In this research, the effect of the mentioned parameters on the discharge coefficient, hydraulic characteristics of the flow including flow rate, the water surface profile and energy variations were investigated numerically. The result of this research was presented by a nonlinear equation. In this study, the effect of weir wall angle, weir height and hydraulic head on the discharge coefficient of trapezoidal side weirs was investigated numerically using FLUENT software and also the numerical results were compared with the experimental data. The results of the simulation were in a good agreement with the experimental data . The flow coefficient (Cm) does not depend on several hydraulic and geometric parameters. The results also showed that the side weir with a wall slope of z = 1 has better performance compared to the other two angles. Because it has the highest amount of the discharge coefficient among different overflow heights. Also, the velocity decreases with a greater slope near the side overflow. It can be concluded that the lower the overflow height, the greater the depth velocity changes will be compared to other models under different wall slopes
Weirs are one of the most important structures for measuring and regulating flow rate. They are also simple hydraulic structures used to control the water level and measure the flow rate in canals. Lateral weirs are sometimes known as side weirs. Side weirs are usually made in various geometric shapes such as rectangular, arched, trapezoidal and triangular. In trapezoidal side weirs, weir height, hydraulic head, and weir wall angle affect the discharge coefficient. In this research, the effect of the mentioned parameters on the discharge coefficient, hydraulic characteristics of the flow including flow rate, the water surface profile and energy variations were investigated numerically. The result of this research was presented by a nonlinear equation. In this study, the effect of weir wall angle, weir height and hydraulic head on the discharge coefficient of trapezoidal side weirs was investigated numerically using FLUENT software and also the numerical results were compared with the experimental data. The results of the simulation were in a good agreement with the experimental data . The flow coefficient (Cm) does not depend on several hydraulic and geometric parameters. The results also showed that the side weir with a wall slope of z = 1 has better performance compared to the other two angles. Because it has the highest amount of the discharge coefficient among different overflow heights. Also, the velocity decreases with a greater slope near the side overflow. It can be concluded that the lower the overflow height, the greater the depth velocity changes will be compared to other models under different wall slopes

کلیدواژه‌ها [English]

  • Side Weir
  • Trapezoidal Plan
  • Discharge Coefficient
  • . FLUENT software
  • Turbulence models