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İç akışlardaki hidrodinamik giriş uzunluğu üzerine hesaplamalı akışkanlar dinamiği analizleri

Computational fluid dynamics analyses on the hydrodynamic entry length in internal flows

Journal Name:

  • Pamukkale Üniversitesi Mühendislik Bilimleri Dergisi

Publication Year:

  • 2017
DOI: 
10.5505/pajes.2017.58908

Key Words:

Keywords (Original Language):

Author NameUniversity of Author
Abstract (2. Language): 
In the present numerical study, effects of the shape of the cross-section and their surface roughness on the pipe hydrodynamic entry length have been investigated for various Reynolds (Re) numbers. Standard k-s turbulence model has been adopted to analyze the turbulent flows in circular, square and equilateral triangle cross-sectional pipes. Analyses indicate that the rough surfaces have the shorter entry lengths than that of the smooth surfaces and increasing surface roughness reduces the entry length regardless of the cross-section of the pipes. The equila teral triangle pipes have the longest while circular cross-sectional pipe has the shortest entry lengths. Re number has the significant effect on the entry length and it is seen that the higher the Re number the longer the entry length.
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Abstract (Original Language): 
Bu sayısal çalışmada, en kesit şekillerinin ve yüzey pürüzlülüklerinin borulardaki hidrodinamikgiriş uzunluğuna olan etkileri farklı Reynolds (Re) sayıları için incelenmiştir. Dairesel, kare ve eşkenar üçgen kesitli borulardaki türbülanslı akışı analiz etmek için standart k-s türbülans modeli kullanılmıştır. Analizler pürüzlü yüzeyli borulardaki giriş uzunluğunun pürüzsüz borulardakine göre daha kısa olduğunu göstermiştir. Ayrıca, yüzey pürüzlülüğünü artırmak borunun en kesit şeklinden bağımsız olarak giriş uzunluğunu kısaltmaktadır. Eşkenar üçgen kesitli boruların en uzun, dairesel kesitli boruların ise en kısa giriş uzunluğuna sahip oldukları görülmüştür. Re sayısı giriş uzunluğu üzerinde önemli etkilere sahiptir ve Re sayısı ne kadar büyürse giriş uzunluğunun da o kadar arttığı sonucuna varılmıştır.
FULL TEXT (PDF): 
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  • Turkish

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