نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانش آموخته کارشناسی ارشد گروه مهندسی آب، واحد اهواز، دانشگاه آزاد اسلامی، اهواز، ایران.

2 دانشیارگروه علوم و مهندسی آب، واحد اهواز، دانشگاه آزاد اسلامی، اهواز، ایران.

چکیده

در برخی رودخانه_ها سازه_هایی در مسیر حرکت آب ساخته می_شوند که باعث ایجاد گردابه‌های نوسانی در پایین‌دست این سازه_ها می‌گردند. گردابه‌های ایجاد شده نیروهای نوسانی به این سازه_ها وارد کرده و پایداری آنها را دچار مشکل می‌نمایند. در همین راستا در این تحقیق با استفاده از شبیه سازی عددی با نرم افزار SolidWorks به بررسی شکل و ابعاد موانع بر میزان نیروی وارده از طرف گردابه بر سازه_های آبی پرداخته شد. نتایج نشان داد که هر چه ابعاد مانع کوچک تر می‌شود مقدار گردابه ایجاد شده کمتر می گردد، بیشترین میزان 2/5 St= در 50000 Re= و برای مانع با قطر 09/0 صورت می گیرد. همچنین مانع مثلثی باعث ایجاد بیشترین گردابه در پایین دست خود شد و بیشترین مقدار عدد استروهال 8/7 St = در 4/0 V = در مانعی با قطر 05/0 D = رخ داد. همچنین در مانع مربعی بیشترین مقدار گردابه در 05/0 D = به قوع پیوست.

کلیدواژه‌ها

عنوان مقاله [English]

Numerical Study on Vortices in Collision of Flow with Circular, Square, Triangular, and Pentagonal Barriers of Different Diameters

نویسندگان [English]

  • Saja Kanan 1
  • Mohammad Heidarnejad 2

1 Former M.Sc. Student, Department of Civil Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran

2 Associate Professor, Department of Water Science Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.

چکیده [English]

Numerical Study on Vortices in Collision of Flow with Circular, Square, Triangular, and Pentagonal Barriers of Different Diameters
Structures constructed on rivers induce downstream oscillating vortices. These vortices apply oscillating loads on the structure and harm its stability. This paper carried out numerical simulations in SOLIDWORKS to explore the effects of the barrier shape and size on the load applied by the vortex on structures constructed in water streams. It was found that a reduction in the barrier size diminished the vortices. The highest Strouhal number was calculated to be 5.2 at a Reynolds number of 5000 and a barrier diameter of 0.09. The maximum downstream vortices were induced by the triangular barrier, and the maximum Strouhal number occurred to be 7.8 at a velocity of 0.4 and a barrier diameter of 0.05. The maximum vortices induced by the square barrier occurred at a barrier diameter of 0.05.
Keywords: Strouhal number, Reynolds number, Barrier, Physical model, Oscillation

کلیدواژه‌ها [English]

  • Strouhal number
  • Reynolds number
  • Barrier
  • Physical model
  • Oscillation
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