NUMERICAL INVESTIGATION OF TWO DIMENSIONAL SEDIMENT TRANSPORT IN NON-EQUILIBRIUM CONDITIONS

Abstract

A two-dimensional model, under non equilibrium condition, consists of three components has been developed to determine suspended load over an erodible layer. The first component, prepares unstructured triangular meshes. The second component, employs the shallow water equation system to calculate flow treatment, is hydrodynamic component. The last component, determines suspended sediment and bed deformation, is morphodynamic component. The governing equations solved by explicit Finite volume method and discretized by Total Variation Diminishing scheme. In addition, in order to obtain a more accurate solution, two turbulence models has been adjoined to the governing equation. The numerical results of developed model are compared with the results of Flower 3D software. The model was examined for two hypothetical cases. The acceptable compatibility between numerical results of developed model and Flow3D software had been recognized. However, results of mixing length turbulence model are compatible than eddy viscosity model

Keywords

• Finite Volume Method, Total Variation Diminishing scheme, Sediment Transport, Turbulence model, Non-Equilibrium condition

DENGEDE OLMAYAN ŞARTLAR ALTINDA KATI MADDE TAŞINIMININ İKİ BOYUTLU OLARAK SAYISAL İNCELENMESİ

Abstract

Askıda katı madde içeren hareketli tabanlı bir yatakta dengede olmayan şartlar altında taban profilinin değişiminin belirlenmesi için üç bileşenden oluşan iki boyutlu bir model geliştirilmiştir. Birinci bileşen çözüm için düzensiz üçgen ağlar oluşturmaktadır. İkinci bileşen sığ su denklemlerini kullanarak akımı modelleyen hidrodinamik bileşendir. Son bileşen ise tabandaki değişimi ve askıdaki katı madde hareketini hesaplayan morfodinamik bileşendir. Denklemler açık Sonlu Hacimler Yöntemi, Toplam Değişim Azalması şeması kullanılarak çözülmüştür. Ayrıca, daha doğru çözüm elde edebilmek için genel denklemlere iki tane çalkantı modeli eklenmiştir. Geliştirilen modelin sonuçlarını denemek amacıyla iki tane hipotez örnek çözülmüştür. Geliştirilen modelden elde edilen sayısal sonuçlar Flow3D yazılımı sonuçlarıyla karşılaştırılmış ve uyumlu olduğu görülmüştür. Ancak, karışım uzunluğu çalkantı modeli sonuçları eddy viskozitesi modeline göre daha uyumludur

Keywords

• Sonlu Hacimler Yöntemi, Toplam Değişim Azalması Şeması, katı Madde Taşınımı

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