İç akışlardaki hidrodinamik giriş uzunluğu üzerine hesaplamalı akışkanlar dinamiği analizleri

Öz

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.

Anahtar Kelimeler

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

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