Natural convection in a triangular cross section roof under daylight conditions

Gedikli, Hasan; KÜÇÜK, HAYDAR

Natural convection in a triangular cross section roof under daylight conditions

Haydar KÜÇÜK, (Gümüşhane Üniversitesi, Mühendislik Bölümü, Gümüşhane, Türkiye)

Hasan GEDİKLİ (Karadeniz Teknik Üniversitesi, Makina Mühendisliği Bölümü, Trabzon, Türkiye)

Isı Bilimi ve Tekniği Dergisi

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Yıl: 2010 Cilt: 30 Sayı: 1 Sayfa Aralığı: 99 - 110 Metin Dili: Türkçe İndeks Tarihi: 29-07-2022

Natural convection in a triangular cross section roof under daylight conditions

Öz:

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.

Anahtar Kelime:

Konular: Termodinamik

Gündüz şartlarında üçgen kesitli çatıda doğal taşınım

Öz:

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.

Anahtar Kelime:

Konular: Termodinamik

Belge Türü: Makale Makale Türü: Araştırma Makalesi Erişim Türü: Erişime Açık

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APA	KÜÇÜK H, Gedikli H (2010). Natural convection in a triangular cross section roof under daylight conditions. , 99 - 110.
Chicago	KÜÇÜK HAYDAR,Gedikli Hasan Natural convection in a triangular cross section roof under daylight conditions. (2010): 99 - 110.
MLA	KÜÇÜK HAYDAR,Gedikli Hasan Natural convection in a triangular cross section roof under daylight conditions. , 2010, ss.99 - 110.
AMA	KÜÇÜK H,Gedikli H Natural convection in a triangular cross section roof under daylight conditions. . 2010; 99 - 110.
Vancouver	KÜÇÜK H,Gedikli H Natural convection in a triangular cross section roof under daylight conditions. . 2010; 99 - 110.
IEEE	KÜÇÜK H,Gedikli H "Natural convection in a triangular cross section roof under daylight conditions." , ss.99 - 110, 2010.
ISNAD	KÜÇÜK, HAYDAR - Gedikli, Hasan. "Natural convection in a triangular cross section roof under daylight conditions". (2010), 99-110.

APA	KÜÇÜK H, Gedikli H (2010). Natural convection in a triangular cross section roof under daylight conditions. Isı Bilimi ve Tekniği Dergisi, 30(1), 99 - 110.
Chicago	KÜÇÜK HAYDAR,Gedikli Hasan Natural convection in a triangular cross section roof under daylight conditions. Isı Bilimi ve Tekniği Dergisi 30, no.1 (2010): 99 - 110.
MLA	KÜÇÜK HAYDAR,Gedikli Hasan Natural convection in a triangular cross section roof under daylight conditions. Isı Bilimi ve Tekniği Dergisi, vol.30, no.1, 2010, ss.99 - 110.
AMA	KÜÇÜK H,Gedikli H Natural convection in a triangular cross section roof under daylight conditions. Isı Bilimi ve Tekniği Dergisi. 2010; 30(1): 99 - 110.
Vancouver	KÜÇÜK H,Gedikli H Natural convection in a triangular cross section roof under daylight conditions. Isı Bilimi ve Tekniği Dergisi. 2010; 30(1): 99 - 110.
IEEE	KÜÇÜK H,Gedikli H "Natural convection in a triangular cross section roof under daylight conditions." Isı Bilimi ve Tekniği Dergisi, 30, ss.99 - 110, 2010.
ISNAD	KÜÇÜK, HAYDAR - Gedikli, Hasan. "Natural convection in a triangular cross section roof under daylight conditions". Isı Bilimi ve Tekniği Dergisi 30/1 (2010), 99-110.