Ela Aytel ÖZÇELİK BOSTANCI, Sebahattin ÜNALAN

90 Derecelik kare kesitli dirsekte türbülanslı akışın sayısal analizi

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

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

Keywords:

Turbulent Flow In Bend, Turbulence Models, Computational Fluid Dynamics,

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