İç akışlardaki hidrodinamik giriş uzunluğu üzerine hesaplamalı akışkanlar dinamiği analizleri

Year 2017, Volume: 23 Issue: 4, 372 - 377, 18.08.2017

Emre Kahramanoğlu Savaş Sezen Seyfettin Bayraktar

https://izlik.org/JA25PB52SE

Abstract

Bu sayısal çalışmada, en kesit şekillerinin ve yüzey
pürüzlülüklerinin borulardaki hidrodinamik giriş uzunluğuna olan etkileri farklı
Reynolds (Re) sayıları için incelenmiştir. Dairesel, kare ve eşkenar üçgen
kesitli borulardaki türbülanslı akışı analiz etmek için standart k-e 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.

Keywords

Hesaplamalı akışkanlar dinamiği , İç akışlar , Pürüzlülük , Türbülanslı akışlar , Giriş uzunluğu

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