بررسی آزمایشگاهی تاثیر قطر صفحات مشبک قائم در استهلاک انرژی در پایین دست شیب‌شکن قائم

نوع مقاله : مقاله پژوهشی

نویسندگان

1 استاد، گروه مهندسی عمران، دانشکده فنی و مهندسی، دانشگاه مراغه، مراغه، ایران

2 دانشجوی دکترا، گروه عمران، دانشکده فنی مهندسی، دانشگاه زنجان، زنجان، ایران

3 دانشجوی کارشناسی ارشد، گروه مهندسی عمران، دانشکده فنی و مهندسی، دانشگاه مراغه، مراغه، ایران

10.22034/jewe.2021.260857.1481

چکیده

صفحات مشبک از جمله سازه‌های الحاقی، در پایین‌دست سازه‌های هیدرولیکی است که در سال‌های اخیر جهت استهلاک انرژی و جلوگیری از فرسایش بستر کانال استفاده می‌شود. لذا در پژوهش حاضر از صفحات مشبک قائم در پایین‌دست شیب‌شکن قائم به‌منظور استهلاک انرژی استفاده‌شد و تأثیر اندازه روزنه صفحات بر میزان استهلاک انرژی بررسی شد. آزمایش‌ها در قطرهای نسبی 067/0، 133/0 و 2/0 با تخلخل 50% و محدوده عمق بحرانی نسبی 13/0 تا 39/0 انجام شد. نتایج نشان داد با افزایش قطر نسبی صفحات مشبک قائم، پرش هیدرولیکی تشکیل یافته در پشت صفحات مشبک مستغرق شده و سبب کاهش عملکرد این صفحات در استهلاک انرژی می‌گردد. همچنین نتایج نشان داد که افزایش قطر نسبی صفات مشبک سبب افزایش عمق استخر شیب‌شکن قائم می‌شود به‌گونه‌ای که صفحه مشبک با قطر نسبی 2/0 در مقایسه با قطر نسبی 067/0 عمق استخر را به میزان 21% افزایش می‌دهد. برای انرژی باقی‌مانده نسبی نیز با اینکه افزایش قطر صفحات مشبک سبب افزایش ناچیز انرژی باقی‌مانده نسبی می­شود، اما این صفحات حداقل انرژی باقی‌مانده نسبی را ایجاد کرده و محدوده عدد فرود پایین‌دست را برای هر سه قطر نسبی صفحات در بازه 31/1 تا 8/1 محدود می‌کند.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Experimental Study of the Effect of Vertical Screen Diameter on Energy Dissipation at Downstream Vertical Drop

نویسندگان [English]

  • Rasoul Daneshfaraz 1
  • Amir Ghaderi 2
  • Navid Khajei 3
1 Professor, Department of Civil Engineering, Faculty of Engineering, University of Maragheh, Maragheh, East Azerbaijan, Iran
2 Ph.D Scholar, Department of Civil Engineering, Faculty of Engineering, University of Zanjan, Zanjan, Iran
3 M.Sc. Student, Department of Civil Engineering, Faculty of Engineering, University of Maragheh, Maragheh, East Azerbaijan, Iran
چکیده [English]

Screens are one of the applications at the downstream of hydraulic structures in recent years to dissipate energy and prevent erosion of the channel bed. Therefore, in the present study, vertical screens at downstream of vertical drop were used for energy dissipation and the effect of screens pore size on energy dissipation was investigated. Experiments were performed in relative diameters of 0.067, 0.133, and 0.2 with 50% porosity and relative critical depth range of 0.13 ~ 0.39. The results showed that by increasing the relative diameter of the vertical screens, the hydraulic jump formed behind the screens is submerged and reduces the performance of these screens in energy dissipation. The results also showed that increasing the relative diameter of the screens increases the depth of the vertical drop pool so that the screens with a relative diameter of 0.2 compared with the relative diameter of 0.067 increases the depth of the pool by 21%. For the relative residual energy, although increasing the diameter of the screens causes a low increase in the relative residual energy, these screens create the minimum relative residual energy and reduce the downstream Froude number range for all three relative diameters of the plates in the range 1.31 to 1.8 restricts.

کلیدواژه‌ها [English]

  • Energy Dissipater
  • Pool Depth
  • Relative Residual Energy
  • Screen Diameter
  • Vertical Drop
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