90 Derecelik kare kesitli dirsekte türbülanslı akışın sayısal analizi

Yıl 2012, Cilt: 28 Sayı: 1, 15 - 22, 01.02.2012

Ela Aytel Özçelik Bostancı Sebahattin Ünalan

Öz

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

Anahtar Kelimeler

Dirsekte türbülanslı akış, Türbülans modelleri, Hesaplamalı akışkanlar dinamiği

Numerical analysis of turbulent flow in 90 degree square sectioned bend

Öz

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

Anahtar Kelimeler

Turbulent Flow In Bend, Turbulence Models, Computational Fluid Dynamics

Kaynakça

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