İkiz Tabliyeler Arasındaki Akışın Dairesel Kesitli Çubuk ile Kontrol Edilmesi

Yıl 2019, Cilt: 34 Sayı: 1, 193 - 200, 31.03.2019

Tahir Durhasan

https://doi.org/10.21605/cukurovaummfd.601453

Öz

Bu çalışmada, uzun açıklıklı ikiz tabliyeler arasındaki akışın dairesel kesitli çubuk ile kontrol edilmesi hedeflenmiştir. İki tabliye arasındaki mesafenin tabliye yüksekliğine oranı L/H=1,7 ve dairesel kesitli çubuğun çapı 4 mm seçilmiştir. Deneyler Reynolds sayısının Re=23440 değerinde PIV tekniği kullanılarak gerçekleştirilmiştir.  Dairesel kesitli çubuk iki tabliye arasında yatay yönde beş farklı ve dikey yönde üç farklı olmak üzere toplam on beş farklı noktada konumlandırılmıştır. PIV ölçüm sonuçları, dairesel kesitli çubuğun konumlandırıldığı yere bağlı olarak tabliyeler arasındaki ters akış bölgelerini önemli ölçüde etkilediğini ortaya koymuştur. Ayrıca, dairesel kesitli çubuğun iki tabliye arasındaki alt ve üst kayma tabakalarının etkileşimini azalttığı gözlemlenmiştir. Kontrol elamanın bulunmadığı durum için elde edilen Reynolds kayma gerilmesinin maksimum değeri,  dairesel kesitli çubuğun tabliyeler arasında x/D=12,5 ve y/D=0’da konumlandırıldığında durum ile kıyaslandığında %49 oranında azalmıştır.

Anahtar Kelimeler

Akış kontrolü, İkiz tabliye, PIV, Dairesel kesitli çubuk

Flow Control in the Gap of Twin Box Girders by Circular Rod

Öz

In this study, it was aim to flow control in the gap where between twin box girder by rod. The gap ratio of twin box girders and diameter of rod were selected as L/H=1.7 and 4 mm. Experiments were performed using PIV technique at Re=23440. The rod was located in the gap of twin box girders at fifteen different position (five different horizontal direction and three different vertical direction). The results of PIV measurements exhibited that the rod affected significantly reverse flow regions depends on the location. Also, the rod reduced interaction of shear layers on the upper and lower side in the gap. The peak maximum of Reynolds shear stress was decreased by 49% at x/D=12.5 and y/D=0 compared to without rod case.

Anahtar Kelimeler

Flow control, Twin box girder, PIV, Rod

Kaynakça

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