Erciyes Üniversitesi Fen Bilimleri Enstitüsü Fen Bilimleri Dergisi 1012-2354 Erciyes University 90 Derecelik kare kesitli dirsekte türbülanslı akışın sayısal analizi Numerical analysis of turbulent flow in 90 degree square sectioned bend Özçelik Bostancı Ela Aytel OSMANİYE KORKUT ATA ÜNİVERSİTESİ, BAHÇE MESLEK YÜKSEKOKULU, TEKNİK PROGRAMLAR BÖLÜMÜ Ünalan Sebahattin ERCİYES ÜNİVERSİTESİ, MÜHENDİSLİK FAKÜLTESİ, MAKİNE MÜHENDİSLİĞİ BÖLÜMÜ 02 01 2012 28 1 15 22 02 01 2012 Copyright © 1985, Erciyes Üniversitesi Fen Bilimleri Enstitüsü Fen Bilimleri Dergisi 1985 Erciyes Üniversitesi Fen Bilimleri Enstitüsü Fen Bilimleri Dergisi

Bu çalışmada, 90°’lik kare kesitli bir dirsekte, kararlı, sıkıştırılamaz, viskoz ve 3-D türbülanslı akışın sayısal olarak incelenmesi amaçlanmıştır. İncelenen kare kesitli dirsek üzerinde literatürde deneysel çalışma yapılmış olup [10, 12 ve 14], kesiti 80x80 mm2, eğrilik yarıçapı 160 mm, giriş uzunluğu 2500 mm ve çıkış uzunluğu 1500 mm olarak incelenmiştir. Türbülans modeli olarak RNG (ReNormalization Group) k-epsilon modeli, SST (Shear-Stress Transport) k-omega modeli ve RSM (Reynolds Stress Model) modeli seçilmiştir. Sayısal analizler Re=40000’lık hava akışı için gerçekleştirilmiştir. Sonuç olarak, dirsekte türbülanslı akışın sayısal analizi için en uygun modelin RNG k-epsilon modeli olduğu görülmüştür

In this study, steady, incompressible, viscos and 3-D turbulent flow in a 90° square section bend numerical investigation has been aimed. Square section bend examined on experimental studies have been done in the literature [10, 12 ve 14], which has 80x80 mm2 section, 160 mm curvature radius, 2500 mm upstream and 1500 mm downstream. RNG (renormalization group) k-epsilon, SST (shear-stress transport) k-omega and RSM (Reynolds stress model) models are selected. Numerical analysis was carried out for Re=40000 air flow. As a result, it is seen that the most acceptable model for numerical analysis of turbulent flow in bend is RNG k-epsilon turbulence model

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