Journals / Isı Bilimi ve Tekniği Dergisi / 2010 / Cilt: 30 - Sayı: 1

Gündüz şartlarında üçgen kesitli çatıda doğal taşınım

Natural convection in a triangular cross section roof under daylight conditions

Pages
99–110
Publication Date
2022-10-18
DOI
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

It is found out that the aspect ratio and Rayleigh number highly affect the heat transfer on the bottom and inclined walls while heat flux slightly affects.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:The natural convection is numerically investigated in a roof of triangular cross section under constant heat flux with seven different values depending on daylight on the inclined wall, constant wall temperature on the bottom wall and adiabatic on the vertical wall boundary conditions.
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Key Findings & Data:Streamlines, isotherms, local and mean Nusselt numbers are presented for AR=0.25, 0.5, 0.75 and 1.0 and Ra=$10^3, 10^4, 10^5, 10^6$.
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Conclusion & Impact:It is found out that the aspect ratio and Rayleigh number highly affect the heat transfer on the bottom and inclined walls while heat flux slightly affects.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Domain Parameters

Abstract

The natural convection is numerically investigated in a roof of triangular cross section under constant heat flux with seven different values depending on daylight on the inclined wall, constant wall temperature on the bottom wall and adiabatic on the vertical wall boundary conditions. Continuity, momentum and energy equations are solved by using finite volume method for laminar, two-dimensional and steady-state regime. Streamlines, isotherms, local and mean Nusselt numbers are presented for AR=0.25, 0.5, 0.75 and 1.0 and Ra=$10^3, 10^4, 10^5, 10^6$. The amount of heat flux ranges from 163 W/$m^2$ to 808 W/$m^2$ depending on daylight and the Prandtl number is chosen as 0.7. It is found out that the aspect ratio and Rayleigh number highly affect the heat transfer on the bottom and inclined walls while heat flux slightly affects.

Özet

Dikey duvarında adyabatik, alt duvarında sabit sıcaklık ve eğik duvarda gün ışığına bağlı olarak yedi farklı sabit ısı akısı sınır şartları altında üçgen kesitli çatıda doğal taşınım sayısal olarak incelenmiştir. Sürekli, laminer ve iki boyutlu durum için süreklilik, momentum ve enerji denklemleri sonlu hacim metodu kullanılarak çözülmüştür. Akım çizgileri, eş sıcaklık eğrileri, yerel ve ortalama Nusselt sayıları AR=0.25, 0.5, 0.75 ve Ra=$10^3, 10^4, 10^5, 10^6 $için sunulmuştur. Isı akısı gün ışığına bağlı olarak 163 W/$m^2$ ile 808 W/$m^2$ arasında değişmiş ve Prandtl sayısı 0.7 olarak alınmıştır. Alt duvar ve eğik duvarda ısı transferinin en-boy oranı ve Rayleigh sayısı tarafından oldukça fazla etkilenirken ısı akısı tarafından hafif şekilde etkilendiği belirlenmiştir.

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Cite This Article

GEDİKLİ, H., KÜÇÜK, H. (2022). Gündüz şartlarında üçgen kesitli çatıda doğal taşınım. Isı Bilimi ve Tekniği Dergisi, Cilt: 30 - Sayı: 1, 99–110. https://ajindex.com/articles/542603

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