Nazım KURTULMUŞ

Düz Kanal İçerisine Yerleştirilmiş Kare Şekilli Silindir Ardındaki Akış Yapısı

Bu çalışmada, düz kanal içerisine yerleştirilmiş kare silindir ardındaki akış yapısını araştırma amacıyla deneyler gerçekleştirilmiştir. Çalışmadaki belirleyici parametreler, Reynolds sayısı, Re ve bloklama oranı, β sırasıyla 500 ve %25 olarak literatür doğrultusunda belirlenmiştir. Çalışmada, anlık hız alanını ölçmek için, parçacık görüntülemeli hız ölçüm sistemi (PIV) sistemi kullanılmıştır. Zaman ortalama eşdeğer girdaplar,<ω>, ortalama ve anlık akım çizgileri, Ψ, akım yönündeki hız çalkantılarının karelerinin karekökü, urms, türbülans kinetik enerji, TKE dağılımını içeren akış yapıları şekillerle sunulmuştur.

Anahtar Kelimeler:

Akış yapıları, Sınırlandırılmış silindir, PIV

Flow Structures Downstream of Square-shaped Cylinder in Channel

Experiments were conducted to investigate the flow topology downstream of a square-shaped cylinder situated in a straight channel. The critical parameters such as the Reynolds number (Re = 500) and the blockage ratio of the square-shaped cylinder (25%) were determined in light of the literature. A Particle image velocimetry (PIV) system was used to obtain the instantaneous velocity vector map. The flow structures, including the time-mean vorticity distribution, <ω> instantaneous and time-mean streamline topology, Ψ, distributions of streamwise velocity fluctuations, urms, turbulent kinetic energy, TKE are presented with Figures.

Keywords:

Confined cylinder, Flow structures, PIV,

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