İnce Kenarlı Savaklardaki Havalandırma Verimliliğinin Deneysel Olarak İncelenmesi: Debi Etkisi

Year 2023, Volume: 8 Issue: 4, 736 - 741, 31.12.2023

Serhat Küçükali

https://doi.org/10.35229/jaes.1402216

Abstract

Bu deneysel çalışmada savakların havalandırma performansı debi etkisi altında incelenmiştir. Bu amaçla, düşme yükseklikleri 0,35-0,535 m arasında ve birim genişlikten geçen debinin 0,03-0,063 m2/s aralığında değişen 90° üçgen ince kenarlı bir savakta deneyler yapılmıştır. Deneysel verilerin analizi sonucu, birim genişlikten geçen ile havalandırma verimliliği arasında pozitif bir korelasyon bulunmuş ve ortaya çıkan ilişki, düşme yüksekliği ve birim genişlikten geçen debinin fonksiyonu olarak tanımlanmıştır. Havalandırma verimliliği yük kaybının 3/4’cü, birim genişlikten geçen debinin ise 1/3’cü üssü ile ilişkilendirilmiştir. Önerilen ampirik formülün tahmin kapasitesi diğer ampirik formüllerle ortalama bağıl hata değerleri açısından karşılaştırılmıştır. Ayrıca düşüm yüksekliğinin yük kaybına eşit olduğu varsayıldığında, hidrolik sırçamdaki havalandırma verimliliğinin yük kaybında olan bağımlığının ince kenarlı savakta da geçerli olduğu gözlemlenmiştir.

Keywords

İnce kenarlı savak, doğal havalandırma, çözünmüş oksijen, düşüm yüksekliği, debi etkisi

An Experimental Investigation on Aeration Performance of Sharp-crested Weirs: Discharge Effect

Abstract

In this experimental study, the aeration performance of weirs was investigated by means of the discharge effect. For this purpose, experiments were performed at a 90º V-notch weir with drop heights ranging from 0.35-0.535 m and unit discharges ranging from 3x10-2 to 6.33x10-2 m2/s and E20 varied in the range of 0.13-0.23. A positive correlation was found between the unit discharge and aeration efficiency and the resulting relationship was defined by a power function in terms of drop height and unit discharge. It was found that aeration efficiency is in proportion to the 3/4 power of drop height and 1/3 power of unit discharge. The proposed empirical formula prediction capacity has been compared with the other empirical formulas in terms of their average relative error values. Additionally, by assuming a drop height equal to head loss, it was observed that hydraulic jump aeration efficiency dependence on head loss continued for weirs indicating the free-surface macro turbulence's main role in the process.

Keywords

sharp-crested weir, self-aeration, dissolved oxygen, drop height, discharge effect

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