Dikdörtgen Kesitli Bir Kanal İçerisinde Farklı Açılara Sahip Altıgen Kanatçıklı Yüzeylerde Hız ve Sıcaklık Dağılımının Nümerik Olarak İncelenmesi

Year 2022, , 176 - 186, 15.01.2022

İlhan Volkan Öner

https://doi.org/10.17714/gumusfenbil.972068

Abstract

Isınan yüzeylere kanatçık ilavesi ile ısı çekilerek yüzeyin soğutulması işlemi birçok sistem için yaygın olarak kullanılmaktadır. Kanatçıklar ısı transfer yüzey alanlarını arttırarak ısı transferinin iyileşmesini sağlanmaktadırlar. Bu çalışmada, dikdörtgen bir kanal içine aynı yüzey alanına sahip, aynı dizilimde 0°, 15° ve 30° farklı açılarla yerleştirilen altıgen şeklindeki kanatçıkların üzerinden sabit sıcaklık ve sabit Reynolds sayılarında akan iş akışkanı havanın hız ve sıcaklık dağılımları Ansys Fluent paket programı kullanılarak numerik olarak analiz edilmiştir. Yapılan analizler 15° dizileme sahip kanatçıklarda, sınır tabakanın yenilenmesinden ve kanatçıklar arasında oluşan türbülanstan dolayı ısı transfer katsayısının iyileştiği sonucuna varılmıştır. Hesaplamalı akışkanlar dinamiği (CFD) analizi, Ansys Fluent paket program ile gerçekleştirilmiştir. Çalışmadan elde edilen sonuçlarda tüm kanatçık açılarında (0° ,15° ve 30°) basınç düşümü, sıcaklık ve hız dağılımları gösterilmiştir.

Keywords

Ansys-Fluent, CFD, Isı transferi, Kanatçık dizilim açısı

A numerical investigation of velocity and temperature distribution on a heat sink with hexagonal fins facing at different angles in a rectangular duct

Abstract

The cooling of hot surfaces through drawing heat by means of fins attached to the surface is widely used technique in many systems. The fins increase the heat transfer surface area, thereby improving the heat transfer. In this study, the velocity and temperature distributions of the working fluid, air, flowing at constant temperature and constant Reynolds numbers over the hexagonal fins, placed in a rectangular duct, having the same surface area and same arrangement but facing at different angles to the flow plane; 0°, 15° and 30°, were analyzed numerically. Computational fluid dynamics (CFD) analysis was carried out with Ansys Fluent. The results were obtained for pressure drop, temperature and velocity distributions at all angles (0°, 15° and 30°). As a result of the analyses performed, 15° facing angle was concluded to be the best by the virtue of the fact that the heat transfer coefficient was improved by the renewal of the boundary layer and by the turbulence occurred between the fins.

Keywords

Ansys-Fluent, CFD, Fin facing angle, Heat transfer

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