Sığ suda yan yana silindirler arasına akışa dik yerleştirilen plakaların akış özelliklerine etkisi

Yıl 2018, Cilt: 24 Sayı: 4, 582 - 585, 17.08.2018

Mustafa Atakan Akar , Hüseyin Akıllı , Oğuz Baş Burcu Oğuz Engin Pınar , Beşir Şahin

Öz

Bu
çalışmada yan yana iki silindir arasına akış doğrultusuna dik yönde
yerleştirilen plakaların silindirler arkasındaki akış bölgesine etkisi deneysel
olarak Parçacık Görüntülü Hız Ölçümü (PIV) yöntemi ile incelenmiştir. Akrilik
malzemeden üretilen dairesel silindirlerin çapı D=40 mm’dir. Deneyler süresince hw=20

mm derinliğindeki sığ su akışında akış
görüntüleri

hl=10 mm yükseklikten alınmıştır. Suyun akış hızı U_∞ =125 mm/sn
ve silindirlerin çapına bağlı Reynolds sayısı

ReD=5000’dir.
Yükseklikleri 2 mm artımla

H=2 mm ile 10mm arasında değişen beş farklı plaka
daimi olmayan akışı kontrol etmek için kullanılmıştır. Bütün durumlarda açıklık
oranı G/D=1.25 

olarak sabit tutulmuştur. Deneysel olarak elde
edilen verilerin bilgisayarda işlenmesiyle, boyutsuz Türbülans Kinetik Enerji
değerleri ve ortalama hız vektörleri elde edilmiştir. Sonuç olarak, plaka
kullanımı akış kontrolündeki etkinliğini net bir şekilde ortaya koymaktadır. 

H=6 mm plaka yüksekliğinden sonra TKE değerlerinde
dikkate değer bir azalma gözlenmektedir. Akış kontrolünün sağlandığı en etkili
plaka yüksekliği ise H=10 

mm olarak görülmektedir.

Anahtar Kelimeler

Dik plaka, Girdap, Pasif kontrol, PIV, Sığ su

The effect of the splitter plates on flow characteristics that are vertically placed to the flow between side by side cylinders in shallow water

Öz

In
this paper, flow changes were observed via Particulate Image Velocimetry (PIV)
technique in shallow water flow for two side by side circular cylinders which a
vertically placed splitter plate (VSP) was placed between them. The circular
cylinders made of acrylic material have a diameter of D=40



















mm. Throughout the experiments water height
was 

hw=20 mm and flow images were taken at the elevation
of

hl=10 mm. The free stream velocity was U_∞ = 125mm/sec and Reynolds Number was ReD=5000 

based on diameters of circular cylinders.  Five different VSPs varied from heights of

H=2 mm to 10 mm with an increment 2 mm were used
to control unsteady flow. The gap/diameter ratio was

G/D=1.25 for all cases. Dimensionless Turbulence
Kinetic Energy values and time-averaged velocity vectors ​​were acquired by
processing experimentally obtained data on a computer. As a result, the usage
of splitter plate has shown its effectiveness on flow control. After the plate
height of

H=6 mm, TKE values were decreased significantly.
The most effective plate height on the flow control was seen as H=10 

mm.

Anahtar Kelimeler

Vertical splitter plate, Vortex, Passive control, PIV, Shallow water

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