مطالعة آزمایشگاهی تعادل نیروها و اندرکنش جریان بین کانال اصلی و سیلاب‌دشت‌ها در کانال مرکب مورّب با سیلاب‌دشت‌های شیب‌دار

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه عمران، دانشکده مهندسی، دانشگاه بوعلی سینا.

2 گروه عمران، دانشکدة مهندسی، دانشگاه بوعلی سینا.

چکیده

در کانال‌های مرکب غیرمنشوری به‌دلیل تبادل جرم و اندازه حرکت بین کانال اصلی و سیلاب‌دشت‌ها، اندرکنش جریان بین زیربخش‌های کانال نسبت‌به کانال‌های مرکب منشوری بیشتر است. درنتیجه در این کانال‌ها مطالعة تنش برشی ظاهری ایجاد‌شده در فصل مشترک قائم بین کانال اصلی و سیلاب‌دشت‌ها پیچیده‌تر است. در پژوهش حاضر توزیع سرعت و تنش برشی در مقاطع مختلف و در طول ناحیۀ اریب کانال مرکب به‌صورت آزمایشگاهی اندازه‌گیری شده‌است. سپس با استفاده از داده‌های آزمایشگاهی و معادلات اندازه حرکت، اندرکنش جریان بین زیربخش‌های کانال‌ مرکب مورد بررسی قرار گرفته است. اندازه‌گیری‌ها برای دو زاویة اریب 31/11 و 81/3 درجه و در سه عمق نسبی 2/0، 3/0 و 4/0 انجام شده‌است. بررسی‌ها نشان‌دهندة آن است که اندرکنش جریان بین کانال اصلی و سیلاب‌دشت همگرا عموماً بیشتر از اندرکنش جریان بین کانال اصلی و سیلاب‌دشت واگرا است. هم‌چنین شیب عرضی سیلاب‌دشت‌ها سبب افزایش مقدار نیروی برشی ظاهری در فصل مشترک بین کانال اصلی و سیلاب‌دشت‌ها شده‌است.

کلیدواژه‌ها

عنوان مقاله [English]

Experimental Study of Force Balance and Interaction between Flow in the Main Channel and on the Floodplains in Skewed Compound Channel with Inclined Floodplains

نویسندگان [English]

  • Mostafa Dolati Mahtaj 1
  • Bahram Rezaei 2
1 Department of Civil Engineering, Faculty of Engineering, Bu-Ali Sina University, Hamedan, Iran.
2 Department of Civil Engineering, Faculty of Engineering, Bu-Ali Sina University, Hamedan, Iran.
چکیده [English]

In non-prismatic compound channels due to the mass and momentum exchange between the main channel and floodplains, the flow interaction between channel sub-sections is higher than prismatic compound channels. As a result, in this form of channels, the study of apparent shear forces create at the vertical interface between the main channel and floodplains are much more complex. In the present research, the velocity and boundary shear stress distributions were measured at different sections along the skew part of the flume. Also using the experimental data and the momentum equations the flow interaction between the main channel and floodplains have been investigated. Measurements have been performed for two skew angles of 11.31 and 3.81 degrees and three relative depths of 0.2, 0.3 and 0.4. Investigations indicate that the flow interaction between the main channel and the converging floodplain is generally greater than the flow interaction between the main channel and the diverging floodplain. Also, the side slope of the floodplains, has increased the amount of apparent shear force at the interface between the main channel and floodplains.

کلیدواژه‌ها [English]

  • Flow interaction
  • Force balance
  • Skewed compound channel
  • Inclined floodplains
  • Apparent shear force

مراجع

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