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Hidrolik Sistemlerdeki 90° Bükümlü Borularda Oluşan Basınç Kayıplarının Sayısal Olarak İncelenmesi

Hidrolik sistemler, günümüzde birçok alanda kullanılmaktadır. Özellikle yüksek güç ihtiyacı olan işlerde tercih edilmektedir. Hidrolik sistemler temelde birkaç basit devre elemanı ve bu elemanları birbirlerine bağlayan devre iletim parçalarından, iletim ve bağlantı parçaları ise borular, hortumlar, rakor, dirsek gibi bağlantı elemanlarından oluşmaktadır. Hidrolik devrelerde enerji tasarrufu ve düşük maliyetli bir sistem oluşturabilmek için minimum basınç kaybı oluşturacak şekilde devrenin tasarlanması gerekmektedir. İletim boruları basınç kaybı yaratan önemli devre elemanlarının başında gelmektedir. Bu çalışmada 90° bükülmüş bir hidrolik devre borusunda meydana gelen basınç kayıpları sayısal olarak hesaplanmıştır. İlk olarak büküm yarıçapının basınç kaybına etkisi, daha sonra büküm sırasında oluşacak ovallik (büküm sırasında oluşan daralmalar) incelenmiştir. Sonuç olarak; büküm yarı çapının artmasının basınç kayıplarını azalttığı, ovalitenin yaklaşık %15’e kadar çok fazla bir basınç kaybı oluşturmadığı ancak bu değerden sonra basınç kayıplarının arttığı tespit edilmiştir

Anahtar Kelimeler:

Basınç kaybı, Hidrolik boru, Hidrolik sistemler, Ovalite, Verimlilik

Numerical Investigation of Pressure Drops Occurring in 90° Elbow Pipes in Hydraulic Systems

Hydraulic systems are used in many fields today. It is especially preferred in areas requiring high power. Hydraulic systems basically consist of a few simple circuit elements and circuit transmission parts that connect these elements. Transmission and connection parts consist of pipes, hoses, and fittings such as unions and elbows. In order to create an energy-saving and low-cost system in hydraulic circuits, The circuit must be designed to create a minimum pressure loss. Circut pipes are one of the most important system elements that create pressure loss. In this study, pressure drops occurring in a hydraulic circuit pipe bent at 90° were investigated numerically. First of all, the effect of the bending radius on the pressure drop was examined, then the ovality that will occur during bending (narrowing during bending) was examined. As a result; it has been determined that increasing in the bending radius reduces the pressure drops, the ovality up to %15 does not cause a pressure drop but after this value, the pressure drops increase.

Keywords:

Efficiency, Hydraulic pipe, Hydraulic systems, Ovality, Pressure drop,

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