Farklı Geometrili Kalın Kenarlı Savakların Akım Karakteristiklerinin Sayısal Olarak İncelenmesi

Year 2025, Volume: 17 Issue: 1, 247 - 256

Abdulkadir Demirçelik , Mehmet Mustafa Duman , Erdinç İkincioğulları

Abstract

Kalın kenarlı savaklar, su seviyesini belirleme ve akım hızını düzenleme amaçları ile kullanılan önemli hidrolik yapılardır. Genellikle memba ve mansap yüzeyleri düşey olarak tasarlanan bu yapıların debi deşarj kapasitesini arttırabilmek için memba ve mansap yüzeyleri açılı olacak şekilde yeni öneriler literatürde mevcuttur. Bu çalışmada, kalın kenarlı savakların kretinin eğimli olması ve memba-mansap yüzeyinin basamaklı olarak tasarlanması durumunda akım karakteristiğine etkisi sayısal olarak incelenmiştir. Sayısal analizler için açık kaynak kodlu OpenFOAM yazılımı ve k-ε türbülans modeli kullanılmıştır. Sayısal sonuçlar, literatürdeki dikdörtgen kesitli bir çalışmanın sonuçları (Imanian vd., 2021) ile doğrulanmıştır. Elde edilen sonuçlara göre, tasarlanan yeni modellerin deşarj kapasitesinin klasik kalın kenarlı savağa oranla %4 civarında daha yüksek olduğu, kreti negatif eğimli olarak tasarlanan modellerin deşarj kapasitesinin daha yüksek olduğu, memba ya da mansap yüzeyi basamaklı olarak tasarlanan modellerde deşarj kapasitesinin daha yüksek olduğu ve akım ayrışma bölgesinin daha düşük olduğu gözlenmiştir.

Keywords

Kalın kenarlı savak, debi deşarj katsayısı, OpenFOAM, Hesaplamalı Akışkanlar Dinamiği (HAD)

Numerical Investigation of Flow Characteristics of Broad-Crested Weirs with Different Geometry

Abstract

Broad-crested weirs are important hydraulic structures used for water level control and flow regulation. In the literature, novel designs with upstream and downstream slope angles have been made to increase the discharge capacity of these structures, which are generally designed with vertical upstream and downstream faces. This study numerically investigates the effect on the flow characteristics of broad-crested weirs whose crest is inclined and whose upstream and downstream faces are stepped. The open-source software OpenFOAM and the k-ε turbulence model are used for the numerical analysis. The numerical results are validated with the literature study of a classical broad-crested weir (Imanian et al., 2021). According to the results, it is seen that the discharge capacity of the newly designed models is about 4% higher than the classical broad-crested weir, and the discharge capacity of the models with negative crest slope is higher. In addition, the discharge capacity is higher, and the flow separation zone is lower in the models designed with stepped upstream and downstream surfaces.

Keywords

Broad-crested weir, discharge coefficient, OpenFOAM, CFD

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