Modares Civil Engineering journal
مهندسی عمران مدرس
MCEJ
Engineering & Technology
http://mcej.modares.ac.ir
1
admin
2476-6763
10.22034
fa
jalali
1393
8
1
gregorian
2014
11
1
14
3
online
1
fulltext
fa
تاثیر عدد فرود جریان بر الگوی جریان و آبشستگی اطراف آبشکنهای سری در مسیر مستقیم در حالت مستغرق و غیرمستغرق
Effect of Froude Number on flow pattern and scour around T-shaped spur dikes under submerged and unsubmerged condition
در این تحقیق به مطالعه آزمایشگاهی الگوی جریان و آبشستگی پیرامون آبشکن¬¬های سرسپری سری مستغرق و غیرمستغرق در مسیر مستقیم پرداخته ¬می¬شود. بررسی الگوی آبشستگی در سه زاویه مختلف قرارگیری آبشکن نسبت به ساحل مجاور، در درصد استغراق¬های مختلف و سه عدد فرود جریان نشان¬دهنده افزایش عمق ماکزیمم آبشستگی در لبه بالا دست آبشکن¬ها با افزایش عدد فرود و کاهش درصد استغراق است. همچنین به¬دلیل تاثیر آبشکن¬های سری، عمق ماکزیمم آبشستگی در آبشکن سوم کمتر از آبشکن دوم، و آبشکن دوم کمتر از آبشکن اول است. با کاهش عدد فرود و افزایش درصد استغراق آبشکن¬ها، تاثیر آبشکن¬های سری کمتر شده و آبشکن¬ها تقریبا به صورت مجزا عمل می¬نمایند. محل شروع رسوب¬گذاری و مقدار آن با تغییر عدد فرود جریان، درصد استغراق آّبشکن¬ها و زاویه قرارگیری آن نسبت به ساحل مجاور تغییر می¬کند که در این تحقیق به بررسی و مقایسه این تغییرات پرداخته می¬شود. آزمایش الگوی جریان اطراف آبشکن جاذب، در شرایط آستانه حرکت و در درصد استغراق 50 درصد انجام شد که با بررسی جهت و مقدار سرعت جریان سه¬بعدی و تنش برشی بستر در جلوی بال آبشکن¬ها و محدوده¬ی بین آبشکن¬ها پیش¬بینی قابل قبولی از آبشستگی در پیرامون آبشکن¬های سرسپری بدست می¬آید.
In this research parameters influencing flow pattern and scour around submerged and nonsubmerged series of spur dikes in straight channel were investigated. Scour pattern was investigated for three angles of dikes construction, and three submergence ratio.The result showed that with increasing Froude number and decreaseing submergence ratio, scour decreases. Also because of first spur dike effect on main flow, maximum scour depth in second and third spur dike is less than first one. The location of scour and ridge height change with Froude number, submergence ratio and angle.The three dimention velocity around spur dike were analyzed Then we used flow pattern to forecast scour pattern. In this research parameters influencing flow pattern and scour around submerged and nonsubmerged series of spur dikes in straight channel were investigated. Scour pattern was investigated for three angles of dikes construction, and three submergence ratio.The result showed that with increasing Froude number and decreaseing submergence ratio, scour decreases. Also because of first spur dike effect on main flow, maximum scour depth in second and third spur dike is less than first one. The location of scour and ridge height change with Froude number, submergence ratio and angle.The three dimention velocity around spur dike were analyzed Then we used flow pattern to forecast scour pattern. In this research parameters influencing flow pattern and scour around submerged and nonsubmerged series of spur dikes in straight channel were investigated. Scour pattern was investigated for three angles of dikes construction, and three submergence ratio.The result showed that with increasing Froude number and decreaseing submergence ratio, scour decreases. Also because of first spur dike effect on main flow, maximum scour depth in second and third spur dike is less than first one. The location of scour and ridge height change with Froude number, submergence ratio and angle.The three dimention velocity around spur dike were analyzed Then we used flow pattern to forecast scour pattern. In this research parameters influencing flow pattern and scour around submerged and nonsubmerged series of spur dikes in straight channel were investigated. Scour pattern was investigated for three angles of dikes construction, and three submergence ratio.The result showed that with increasing Froude number and decreaseing submergence ratio, scour decreases. Also because of first spur dike effect on main flow, maximum scour depth in second and third spur dike is less than first one. The location of scour and ridge height change with Froude number, submergence ratio and angle.The three dimention velocity around spur dike were analyzed Then we used flow pattern to forecast scour pattern. In this research parameters influencing flow pattern and scour around submerged and nonsubmerged series of spur dikes in straight channel were investigated. Scour pattern was investigated for three angles of dikes construction, and three submergence ratio.The result showed that with increasing Froude
آبشستگی,آبشکنهای سرسپری سری,عدد فرود,درصد استغراق,الگوی جریان
spur,T shape spur dikes,Froude number,submergence ratio,Flow pattern
71
82
http://mcej.modares.ac.ir/browse.php?a_code=A-16-1000-8360&slc_lang=fa&sid=16
hamed
hoseinzade tabrizi
حامد
حسین زاده تبریزی
100319475328460055553
100319475328460055553
No
دانشجوی کارشناسی ارشد عمران
mohamad
vaghefi
محمد
واقفی
100319475328460055552
100319475328460055552
Yes
bushehr university
استادیار دانشگاه بوشهر