3262

3171

كارشناسي ارشد

﴿ آبياري و زهكشي ﴾

اصفهان : دانشگاه صنعتي اصفهان ، دانشكده كشاورزي

1384

پانزده ، 173 ، [II] ، ص : مصور ، جدول ، نمودار

ص . ع : به فارسي و انگليسي

حسين افضلي مهر

سيد حسين سقائيان نژاد ، پير واي ، جولين

منوچهر حيدر پور ، افشين هنر بخش

مهندسي كشاورزي

ID3171

به فارسي و انگليسي : قابل رويت در نسخه ديجيتالي

AbstractAll previous equations presented for hydraulic geometry of stable channels were mainlybased on uniform flows and thus are not suitable for using in natural rivers andchannels The main objectives of this study were evaluating distribution of local shearstress and Shields parameter in nonuniform cross sections in stable channels and alsodeveloping a model for prediction hydraulic geometry of stable cross sections usingstatistical nonlinear multiple regression For this purpose shear velocity was estimatedusing hydrodynamic methods field measurements of velocity distribution profiles bedsediment characteristics and geometric characteristics of channel cross sections Suitable equations to predict width depth and longitudinal slope of the channel wereproduced using hydraulic parameters such as shear stress flowrate and morphologicalparameters such as sediment particle diameter This study was conducted in twosections For the first part four reaches of a 20 km length in Kaaj River located inChahar Mahal Bakhtiari province were selected The second part including 12reaches of Sheikh Bahaei landscape channels were chosen In general of the totalstudied reaches geometric characteristics of 76 cross sections 338 velocity profile including 5000 point velocity and characteristics of bed materials and surveying datawere recorded By using preliminary calculations morphological and hydrauliccharacteristics were determined Afterwards shear velocity of each profile wasestimated using data acquired from velocity profile and boundary layer characteristicsmethod Eventually shear stress and shields parameter were determined and theirdistribution patterns in non uniform cross sections were studied Results indicated thatdistribution pattern of these two parameters is a useful index for determination ofstability in the studied cross sections In order to predict hydraulic geometry of stablechannels including width depth and slope a model using nonlinear multiple regressionwas produced These equations were estimated separately for river and channel crosssections Results revealed that depth predicting models used in two parts of this studywere significantly effective Presenting proper equations with acceptable correlationcoefficients to anticipate width and slope of channels failed

حسين افضلي مهر

سيد حسين سقائيان نژاد ، پير واي ، جولين

منوچهر حيدر پور ، افشين هنر بخش