Numerical Investigation of Flow Direction and Inlet–Outlet Configuration Effects on Thermo-Hydraulic Performance in T-Junction Tubes

Öz

Bu çalışma, T-şekilli bir boruda akış yönünün ve giriş-çıkış düzeninin termohidrolik performans üzerindeki etkilerini nicelleştirmeyi amaçlamıştır. Simetrik T şeklinde bir boruda çalışma akışkanı olarak su kullanılmıştır. Dört konfigürasyon analiz edilmiştir: ayrışan tek giriş/iki çıkış durumları (K1 ve K2) ve yakınlaşan iki giriş/tek çıkış durumları (K3 ve K4). Bu çalışma, 5000, 10000 ve 15000 Reynolds sayıları ile 313, 333 ve 353 K giriş sıcaklıklarını incelemiştir. K1 en yüksek ortalama Nusselt sayısını ve en düşük basınç düşüşünü üretirken, K2 genel olarak K1'e en yakın performansı göstermiştir. K3, daha güçlü birleşme kayıpları nedeniyle genellikle en yüksek statik basınç düşüşünü vermiştir (K4, K3'ten biraz daha düşüktü). PEC değerlendirmesi, K1'in incelenen tüm çalışma koşullarında daha iyi performans gösterdiğini ortaya koymuştur. Buna karşılık, K3 ve K4 genellikle K1'in altında kalmıştır çünkü statik basınç düşüşü dezavantajları ısı transferi kazanımlarından daha ağır basmıştır. Bu bulgular, optimum bir T-birleşme noktası tasarımının, ısı transferi iyileştirmesi ile yerel kayıplardan kaynaklanan hidrolik kayıplar arasında bir denge kurulmasını gerektirdiğinin altını çizmektedir.

Anahtar Kelimeler

• Akış yönü
• Termal performans
• Giriş-çıkış konfigürasyonu
• T-birleşimli borular.
• Isı Transferi

Etik Beyan

Hazırlanan makale için etik kuruldan izin alınmasına gerek yoktur. Hazırlanan makalede herhangi bir kişi/kurumla çıkar çatışması bulunmamaktadır.

Numerical Investigation of Flow Direction and Inlet–Outlet Configuration Effects on Thermo-Hydraulic Performance in T-Junction Tubes

Öz

Direct comparisons of diverging and converging T-junction configurations under identical operating and boundary conditions remain limited, restricting the design-oriented selection of suitable flow arrangements. This study numerically investigates the effects of flow direction and inlet–outlet topology on the thermo-hydraulic performance of a symmetric equal-diameter T-junction with water as the working fluid. Four configurations were examined: axially fed and branch-fed diverging flows (K1 and K2) and opposing-stream and orthogonal-stream merging flows (K3 and K4). Three-dimensional steady Reynolds-averaged Navier–Stokes simulations were performed in ANSYS Fluent using the standard k"-" ε turbulence model with Enhanced Wall Treatment at Reynolds numbers of 5000, 10000, and 15000 and inlet temperatures of 313, 333, and 353 K. The configurations were compared under identical geometry, total mass flow rate, and wall-temperature conditions using the average Nusselt number, static pressure drop, and a common thermo-hydraulic performance criterion (PEC). K1 consistently provided the highest average Nusselt number and the lowest pressure drop, while K2 was the closest alternative. Relative to K1, the PEC values of K3 and K4 were lower by 43.3–53.4% and 45.0–53.5%, respectively. The results show that stronger local flow interaction in converging configurations does not necessarily yield superior overall performance and provide a quantitative basis for selecting equal-diameter T-junction topologies in water-based thermal and process-piping applications.

Anahtar Kelimeler

• Heat Transfer
• Flow direction
• Thermal performance
• Inlet-outlet configuration
• T-junction tubes.

Etik Beyan

There is no need to obtain permission from the ethics committee for the article prepared. There is no conflict of interest with any person / institution in the article prepared.

Kaynakça

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