Numerical Investigation Of Surface Roughness Effects On The Flow Field In A Swirl Flow

Year 2014, Volume: 19 Issue: 2, 1 - 18, 21.12.2014

Ali Sakı̇n İrfan Karagöz

https://doi.org/10.17482/uujfe.47749

Cited By: 3

Abstract

The aim of this study is to investigate axial and tangential velocity profiles, turbulent dissipation rate, turbulent kinetic energy and pressure losses under the influence of surface roughness for the swirling flow in a cyclone separator. The governing equations for this flow were solved by using Fluent CFD code. First, numerical analyses were run to verify numerical solution and domain with experimental results. Velocity profiles, turbulent parameters and pressure drops were calculated by increasing inlet velocity from 10 to 20 m/s and roughness height from 0 to 4 mm. Analyses of results showed that pressure losses are decreased and velocity field is considerably affected by increasing roughness height.

Keywords

swirl flow; cyclone separators; roughness height

Bir Türbülanslı Akışta Akış Alan Üzerine Yüzey Pürüzlülüğü Etkisinin Sayısal İncelenmesi

Abstract

Bu çalışmanın amacı, bir siklondaki girdaplı akışta yüzey pürüz yükseklik değerinin etkisinde eksenel ve teğetsel hız profilleri, türbülans yayınım oranı, türbülans enerjisi ve basınç kayıplarının araştırılmasıdır. Bu akış için korunum denklemleri Fluent CFD kodu kullanılarak çözülmüştür. İlk olarak sayısal model ve çözüm alanının doğrulanması için elde edilen veriler deneysel sonuçlarla karşılaştırılarak modelin doğrulaması yapılmıştır. Giriş hızı 10-20 m/s arasında ve pürüz yüksekliği 0 ile 4 mm arasında değiştirilerek, hız profilleri, türbülans parametreleri ve basınç kayıpları üzerindeki etkileri incelenmiştir. Analiz sonucunda pürüz yüksekliği arttıkça basınç kayıplarının azaldığı ve hız alanının önemli derecede etkilendiği görülmüştür. 

Keywords

Girdaplı akış, siklon ayırıcılar, pürüz yüksekliği

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