Bir Isı Borusunun Akış ve Isı Transfer Karakteristiklerinin Sayısal Olarak İncelenmesi

Bu çalışmada ısıl kontrol uygulamalarında önemli bir yere sahip olan bir ısı borusunun ısıl ve akış karakteristikleri incelenmiştir. Isı borusunun yoğuşturucu bölüm ve orta adyabatik bölüm uzunluklarının birbirine oranı (Lc/La1) sırasıyla 0,5, 1, 1,25 ve 2 olacak şekilde değiştirilerek dört farklı model geometri oluşturulmuştur. Bu model geometriler için, ısı girdileri 10W ile 80W arasında, doluluk oranı ise %40 ile %80 arasında değiştirilerek Hesaplamalı Akışkanlar Dinamiği aracılığı ile sayısal analizler yapılmıştır. Bu kapsamda, iki fazlı akış yaklaşımı ile zamana bağlı çözümler yapılmış, ısı borusu içindeki akışın sıcaklık ve hız dağılımları belirlenmiştir. Sonuç olarak bu çalışmada incelenen parametre aralığında, model geometrinin yoğuşturucu kısmının uzunluğunun artırılmasının ısıl performansı olumlu yönde etkilediği gözlemlenmiştir. Ayrıca farklı doluluk oranları arasında %50 doluluk oranının optimum ısıl performans sergilediği belirlenmiştir.

Anahtar Kelimeler:

Isı borusu, Hesaplamalı akışkanlar dinamiği (HAD), İki fazlı akış, Isı Transferi

Numerical Investigation of Flow and Heat Transfer Characteristics of a Heat Pipe

In this study, the thermal and flow characteristics of a heat pipe, which has an important place in thermal control applications, have been investigated. Four different model geometries were created by changing the ratio of the lengths of the condenser section and the middle adiabatic section (Lc / La1) of the heat pipe. This ratio has been changed to be 0.5, 1.0, 1.25 and 2.0. For these model geometries, the heat inputs were changed between 10W and 80W, and the occupancy rate between 40% and 80%. Numerical analyzes were made through Computational Fluid Dynamics. In this context, time-dependent solutions are made with the two-phase flow approach. The temperature and velocity distributions of the flow in the heat pipe are determined. As a result, it has been observed that increasing the length of the condenser section of the model geometry has a positive effect on the thermal performance in the parameter range examined in this study. In addition, it was determined that 50% occupancy rate showed optimum thermal performance among different occupancy rates.

Keywords:

Heat pipe, Computational Fluid Dynamics (CFD), Two phase flow, Heat transfer,

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