نتایج جستجو برای: river bend

تعداد نتایج: 89742  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه سیستان و بلوچستان - دانشکده مهندسی 1392
نجمه فرهادملاشاهی, محمد گیوه چی,

flow in natural river bends is a complex and turbulent phenomenon which affects the scour and sedimentations and causes an irregular bed topography on the bed. for the reason, the flow hydralics and the parameters which affect the flow to be studied and understand. in this study the effect of bed and wall roughness using the software fluent discussed in a sharp 90-degree flume bend with 40.3cm ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه اصفهان - دانشکده زبانهای خارجی 1390
لطیفه جلالی, حسین پیرنجم الدین, عباس ابراهیمی,

this thesis attempts to study the representations of the third-world intellectuals in three fictional works by the british-educated trinidadian nobel-winner v. s. naipaul: the mimic men, a bend in the river, and magic seeds. the first one recounts the story of ralph singh’s sense of alienation, his experiences as a colonial politician, and his struggle to give order to his disorderly world thro...

15 صفحه اول
Journal: :journal of hydraulic structures 2013
gholam abbass barani mehdi shahrokhi sardo

in river meandering, when flow passes through a bend, reduction of flow velocity and rising hydrostatic pressure cause super elevation phenomena at outer side and reduction of water surface at inner-side of the bend. a helical motion results, causing erosion of the outer side of the bend. installation of submerged vanes on the stream bed can reduce erosion of the outer bank significantly. in th...

متن کامل
2017
Wen-Dar Guo Jian-Hao Hong Cheng-Hsin Chen Chih-Chiang Su Jihn-Sung Lai

The modeling of flood-induced bend scour near embankment toes can provide important information for river engineering, embankment safety warnings, and emergency action management. During the rainy seasons, short-term general scour and bend scour are the most common causes for the failure of reinforced concrete embankments in Taiwan. To gain a deeper understanding of the scouring process near le...

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Journal: Journal of Hydraulic Structures 2013
Gholam Abbass Barani Mehdi Shahrokhi Sardo

In river meandering, when flow passes through a bend, reduction of flow velocity and rising hydrostatic pressure cause super elevation phenomena at outer side and reduction of water surface at inner-side of the bend. A helical motion results, causing erosion of the outer side of the bend. Installation of submerged vanes on the stream bed can reduce erosion of the outer bank significantly. In th...

متن کامل
ژورنال: علوم آب و خاک 2018
مسجدی, علیرضا, ناصریان, مسعود,

River bend due to particular pattern, called 'Vortex Flow,' has greater erosion than straight path. Occurrence of scour around bridge abutment on curved paths is one of the main reasons for destruction of bridges. Riprap is one of the methods to control the scouring around the bridge abutment. The purpose of this study was to assess stability of the riprap around the bridge abutment at 180 degr...

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ژورنال: علوم آب و خاک 2011
علیرضا مسجدی, , مهدی غلامزاده محمودی, ,

Every year river flooding causes serious damage to the bridges at the time needed most. One of the most effective factors causing bridge failure is scouring around the piers in a river bend. One of the methods to decrease scouring around the bridge piers is fitting them with a coller on the piers. The collars protect the river bed against vortex flow in the vicinity of the pier base. An experim...

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2015
M. Galib Ishak

To construct a bridge as a crossing building on a very wide river it might not used one span only, therefor, in middle of the river it is needed pillar as support. The existing of the pillars will change velocity distribution, surface water and topography of sediment, especially when the pillar is located on the bend of the river where the very large hydraulic can be hepened. Therefore, this st...

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Journal: :مهندسی عمران فردوسی 0
جواد مظفری امیر صمدی سید اسدالله محسنی موحد داود داودمقامی

recognizing of river flow pattern, deposition and erosion areas in meanders is highly important. despite the limitations of the physical models in laboratory investigation of flow pattern in meanders, mathematical models can be helpful. in this research, rsm and les turbulence models have been compared on sharp river bend of a laboratory flume using fluent software. the laboratory flume is a sh...

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ژورنال: علوم آب و خاک 2017
جاسمی زرگانی, ابتسام, کاشفی‌پور, محمود,

Spur dikes are the most common hydraulic structures for river bank protection. Since the construction of this structure causes higher velocities around it, this structure is exposed to erosion. Riprap around the structure nose is one of the most common and economic way to protect spur dike. The main aim of this study is to investigate the riprap stability in a mild 90 degrees bend. Experiments ...

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