مدلسازی عددی دبی جریان روگذر و درون‌گذر در سرریزهای لبه‌پهن گابیونی با شیب جانبی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشکده علوم آب دانشگاه شهید چمران اهواز، اهواز، ایران

2 دانشگاه آزاد اسلامی واحد استهبان، استهبان، فارس

چکیده

سرریزهای گابیونی به دلیل سازگاری با محیط زیست و تأثیر مستقیم بر پارامترهای کیفی رودخانه‌ها و از طرفی در دسترس بودن و سادگی اجرا و طراحی، طی سال‌های اخیر موردتوجه قرار گرفته­اند. در این تحقیق پارامترهای هیدرولیکی سرریز گابیونی لبه پهن با شیب‌های جانبی در حالت جریان آزاد شامل ضریب دبی، پروفیل سطح آب و حجم دبی درون گذر از محیط متخلخل به صورت عددی مورد بررسی قرار گرفته‌اند. درمجموع 21 مدل مختلف شامل 7 هندسه‌ی مختلف سرریز با سه تخلخل مختلف 43 %، 44 % و 46 % و هرکدام در 6 تا 10 دبی مختلف مورد بررسی قرار گرفته است. نتایج نشان می‌دهد که افزایش قطر ذرات به افزایش همزمان دبی درونگذر، ضریب دبی جریان و درنتیجه افزایش افت منجر می‌شود. همچنین اینکه افزایش مساحت محیط متخلخل که درنتیجه‌ی تغییر زوایای خارجی بالادست و پایین دست سرریز از 60 تا 0 درجه هستند، باعث کاهش ضریب دبی و نیز دبی درون گذر خواهد شد. در انتها با استفاده از آنالیز رگرسیون غیرخطی چند متغیره روابطی تجربی برای محاسبه ضرایب دبی و دبی درون گذر از این سرریزها ارائه شده است.
 
 

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Numerical Simulation of the over and through flow Discharge in Broad-Crested Gabion Weirs with side Slopes

نویسندگان [English]

  • M. Tavakol-Sadrabadi 1
  • M. Fathi-moghaddam 1
  • R. Mohammadpour 2
1 School of Water Sciences Engineering, Shahid Chamran University of Ahvaz, Ahvaz, Iran
2 Department of Civil Engineering, Islamic Azad University-Estahban Branch, Fars, Iran
چکیده [English]

During the recent years, Gabion weirs have been taken into consideration due to their compatibility with the environment, positive effect on river’s water quality and their simple design and implementation. In this research, the hydraulic parameters of flow around broad crested gabion weirs (BCGW) with various side slopes are investigated. Overall, a number of 21 models comprising 7 various geometries each with 3 different porosities including (43%, 44%, 46%) and in different discharges were simulated and studied. Results indicated that the discharge coefficient (Cd), through flow discharge and energy dissipation increased by increasing the average diameter of particles. In addition, Increasing the area of the porous media by changing side angles from 0 to 60 reduces the discharge coefficient and through flow discharge. At final stage, experimental equations are presented using Nonlinear Multivariable regression analysis in order to calculate the discharge coefficient and through flow discharge of these structures.

کلیدواژه‌ها [English]

  • Broad-crested gabion weir
  • numerical simulation
  • Through and over flow discharge
  • Discharge Coefficient
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