بررسی آزمایشگاهی هیدرولیک جریان در سرریزهای پله‌ای توری‌سنگی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 Tabriz University, Agricultural faculty, Irrigation department

2 دانشجوی دکتری، گروه علوم و مهندسی آب، دانشگاه تبریز

3 گروه مهندسی آب، دانشگاه تبریز

چکیده

در این تحقیق با استفاده از مدل فیزیکی، مؤلفه­های مختلفی که بر روی اُفت انرژی جریان عبوری از روی سرریزهای پله­ای توری­سنگی مؤثر هستند، مطالعه و با نتایج دیگر محققان نیز مقایسه صورت گرفته است. جریان عبوری از سرریز توری­سنگی هم به صورت درون­گذر و هم به صورت روگذر انجام گرفت. دامنه دبی بکار رفته در این تحقیق در محدوده 5 الی 65 لیتر بر ثانیه است. از ذرات یکنواخت با سه قطر متوسط 10، 25 و 40 میلی­متر استفاده شد. ارتفاع و عرض مدل­های فیزیکی ساخته شده از سرریز پلکانی توری­سنگی به ترتیب 60 و 40 سانتی­متر، با پله­های 3 تایی و شیب­نمای پایین­دست سرریزها (افقی: عمودی) 1:1، 1:2 و 1:3 هستند. آستانه­های انتهایی به کار گرفته شده مستطیلی و شیب­دار هستند. نتایج نشان داد که تأثیر آستانه­ها در سرریزهای پله­ای توری­سنگی با شیب­نمای پایین­دست کمتر، بیشتر از حالتی است که سرریز دارای شیب­نمای پایین­دست تندتر است. تأثیر آستانه­ها بر اُفت انرژی جریان در سرریز با مصالح 40 میلی­متر و شیب­نمای پایین­دست 1:2 حدود 10 درصد بیشتر از همان سرریز با شیب­نمای پایین­دست 1:1 بوده و در سرریز با مصالح 10 میلی­متر و شیب­نمای پایین­دست 1:2 حدود 30 الی 35 درصد بیشتر از همان سرریز با شیب­نمای پایین­دست 1:1 است. لذا وجود آستانه­ها در سرریز پله­ای با بدنه مصالح 10 و 40 میلی­متر به ترتیب بیشترین و کمترین تأثیر را بر اُفت انرژی جریان دارند. از طرفی تأثیر آستانه مستطیلی بر اُفت انرژی جریان حدود 3 الی 4 درصد بیشتر از تأثیر آستانه مثلثی است.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Laboratory Study of the Hydraulics of Flow in Gabion Stepped Weirs

نویسندگان [English]

  • Farzin Salmasi 1
  • Sina Razi 2
  • Ali Hossinzadeh Dalir 3
2 PhD candidate, University of Tabriz, Tabriz-Iran
3 Professor, Water engineering department, University of Tabriz, Tabriz-Iran
چکیده [English]

In this study, different components that affect energy dissipation on flow over gabion-stepped spillways were investigated using physical models, and comparisons were made with the other studies. Flow over gabion spillway was conducted in both through flow and overflow simultaneously. The discharge is in the range of 5 to 65 liters per second.  Uniform particles with three medium diameters of 10, 25, and 40 mm were used. The height and width of the physical models were 60 and 40 cm, respectively, with 3 steps and the downstream slope of weirs was 1:1, 1:2, and 1:3 (V: H). Tow end sills including rectangular and inclined shapes were used. The results showed that the effect of end sills in gabion-stepped weirs with lower slope is more than that of weirs comprising higher slope. The effect of the end sills on the energy dissipation in the weir for d50=40 mm and S=1:2 is about 10% more than the weir with d50=10 mm and S=1:1. In weir including d50=10 mm and S=1:2 is about 30 to 35 percent more than the weir with d50=10 mm and S=1:1. Therefore, the existence of end sills in the weirs with the body of materials of d50=10 and 40 mm have the highest and the least effects on the energy dissipation. On the other hand, the effect of the rectangular end sill on the energy loss is about 3-4% more than that the effect of the triangular end sill.

کلیدواژه‌ها [English]

  • energy loss
  • Gabion
  • Inclined end sill
  • Rectangular end sill
  • Stepped weir
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