بر رسی فشارهای دینامیکی وارد بر صفحه موج نفوذپذیر تحت تابش امواج منظم

نویسندگان

1 دانشجوی دکتری دانشگاه تبریز

2 استاد دانشکده کشاورزی- گروه مهندسی آب

3 استاد دانشکده عمران- گروه مهندسی آب

چکیده

برای طراحی موثر و کارای یک صفحه موج تخمین دقیق فشار دینامیکی و نیروی موج ضروری می‌باشد. این مطالعه به بررسی فشار وارد بر اجزای سازه‌ی یک صفحه موج متشکل از لوله‌های افقی که با فاصله مشخص کنار هم قرار گرفته اند، می‌پردازد. این صفحه امکان تبادل آب دریا در منطقه ساحلی و جذب موثر انرژی را فراهم می‌کند. به این منظور آزمایش‌های فیزیکی بر روی سازه صفحه موج تحت تابش امواج منظم در 3 ارتفاع و 6 پریود موج در عمق آب ثابت 6/0 متر انجام گرفت. در این آزمایش ها از 3 قطر برای استوانه‌های تشکیل‌دهنده سازه استفاده گردید. فشار دینامیکی وارد بر استوانه‌های صفحه موج در امتداد عمقی و پیرامون سازه توسط مبدل فشار برداشت گردید. نتایج نشان داد افزایش تخلخل موجب کاهش تغییرات فشار دینامیکی موج می‌گردد و با افزایش ارتفاع موج تابشی نوسانات فشار برای تخلخل‌های مختلف افزایش می-یابد. هم‌چنین حداکثر تغییرات فشار دینامیکی موج غالبا در زاویه صفر برخورد موج با استوانه‌های سازه ایجاد نمی‌گردد و معمولا در زوایای بیش‌تر از 45 درجه، شاهد افزایش دامنه‌ نوسانات فشار دینامیکی بودیم.

کلیدواژه‌ها


عنوان مقاله [English]

Waves Investigation of Dynamic Pressure on Wave Screen under Regular

نویسنده [English]

  • Naval Azam 1
1 Tabriz university-PHD Candidate
چکیده [English]

For a cost-effective design of wave screen, an accurate estimation of dynamic pressures and wave forces is needed. This study investigated the acting dynamic pressure on elements of wave screen consist of horizontal pipes with constant distance between them. This wave screen can be beneficial for convection and interchange of seawater within the harbor district and, furthermore, perform wave absorption effectively. The physical experiments were performed by considering regular waves under 3 heights and 6 periods of waves and 3 diameters of pipes wave screen. The tests were carried out for 0.6m still water depth value. Dynamic pressure distribution along and around pipes was obtained employing pressure transducers. The experimental results indicated that increasing the porosity decrease pressure difference and with increasing the incident wave height for different porosity increase pressure difference. Furthermore, the maximum dynamic pressure difference does not often occur at the section normal to the wave direction.

کلیدواژه‌ها [English]

  • Regular Wave
  • Porosity
  • Wave Screen
  • Dynamic Pressure
  • Breakwater
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