İnşaat Mühendisliği Bölümü Yayın Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/395
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Article Su Alma Ağzı Giriş Şeklinin Hava Girişli Çevrinti Üzerindeki Ölçek Etkisi(2018) Taştan, Kerem; Yıldırım, NevzatSu alma ağzı giriş şekli, ağız üzerinde su yüzeyinde oluşabilecek hava girişli çevrintinin karakteristiklerini belirlediğinden ağza ait kritik batıklık üzerinde bazı etkilere sahiptir. Bu etkiler hız dağılımı etkisi ve çevrintiyi besleyen ağız debisi etkisi olarak adlandırılabilir. Bu çalışmada 6 farklı ağız giriş şekline (daire, kare, dikdörtgen, eşkenar dörtgen, eşkenar üçgen, yıldız) ve 40 cm2 ve 100 cm2 olmak üzere iki değişik kesit alanına sahip toplam 12 adet su alma yapısına ait kritik batıklık ve kritik batıklığı etkileyen boyutsuz parametreler (su alma yapısına ait Froude, Reynolds ve Weber sayıları) durgun su ortamında deneysel olarak incelenmiştir. Deney sonuçları neticesinde ağız giriş geometrisinin kritik batıklık üzerinde bir boyut etkisine sahip olduğu görülmüştür. Bu nedenledir ki, her bir farklı ağız giriş geometrisi ve akım şartı, kritik batıklık açısından kendine özgü özellikler taşır. Aynı ağız debisinde farklı su alma ağzı giriş şekillerinin kritik batıklık üzerindeki etkisi ise debi değerine göre değişim göstermektedir.Article Effective intake for critical submergence in the case of more than one intake(2017) Taştan, Kerem; Yıldırım, NevzatThe available potential flow solution methods over-estimate the number of effective intake for the prediction of critical submergence in the case of multiple intakes of identical level without partition walls located on the longitudinal line of the canal, because they cannot establish an upper limiting value for the distance between the centers of the intakes. To address this, tests were conducted on dual intakes of identical level located on the longitudinal line of the canal in a cross-flow. In practice, by means of the chart obtained from the experimental results, one can determine the upper limiting value of the distance between the centers of dual intakes beyond which the effect of the intake on the critical submergence of the other intake is negligible. Such an intake is considered a non-effective intake and is disregarded in the prediction of critical submergence. In addition, the effective intake relating to multiple intakes sited in a still-water reservoir is explained.Article Effect of the Bed-Sediment Layer on the Scour Caused by a Jet(2016) Taştan, Kerem; Koçak, Peli̇n Pınar; Yıldırım, NevzatScour caused by a water jet impinging the bedsediment layer is a significant concern for hydraulic engineers. Although several studies investigated the maximum scour depth on the non-cohesive bed-sediment layer, the effect of the bed-sediment layer’s thickness on the scour was not studied. This study investigated the effect of the thickness of the non-cohesive sediment layer at the canal bed on the depth of the scour caused by a water jet. The dimensionless parameters affecting the depth of the scour were obtained via dimensional analysis. Experiments were conducted on two different, non-cohesive bed-sediment layers at the bottom of a rectangular canal for different jet Froude numbers. Experimental results indicated that the depth of the scour increases with the thickness of the bed-sediment layer; this is because as the thickness of the sediment layer increases, the penetration depth of the air bubbles (dragged and enforced by the impinging water jet) through the sediment layer just under the scour hole increases. Due to the buoyancy force, as the air bubbles rise upward, they apply uplift forces and dynamic effects onto sediment particles, dislodging, suspending, and carrying the sediment particles away from the bed. If the thickness of the sediment layer is increased beyond a limiting value for a given flow condition, the maximum depth of the scour does not change (it remains almost constant). The effect of the thickness of the bed-sediment layer on the depth of the scour is present but not excessively large.