ERDAL YILDIRIM, Zeynel Abidin FIRATOĞLU, BÜLENT YEŞİLATA

Çatı Geometrisin Bina Isıl Davranışı Üzerindeki Etkisinin İncelenmesi

Bu çalışmanın amacı yaz ayları için enerji verimliliği açısından, bina çatı geometrisinin iç ortam havasına etkisini araştırmaktır. Bu amaçla Harran konik çatılı yapıları aynı taban alanı, hacim ve termofiziksel özelliklere sahip düz çatılı bina ile karşılaştırılmıştır. Low-Reynolds Number modeling (LRNM) ve k-? türbülans modeli kullanılarak üç boyutlu CFD simülasyonu gerçekleştirilmiştir. Çatı geometrisinin doğal havalandırmaya etkisi araştırılmıştır. Bu kapsamda çapraz havalandırma debisi ve taşınım ısı transfer katsayıları değerlendirilmiştir. Harran evi çapraz havalandırma açısından düz çatılı yapıya göre % 8 daha iyi performans göstermektedir. Sayısal analizler sonucundan tipik bir yaz günü için Harran evinin kubbesinin düz çatıdan % 30 daha az ısı atağına maruz kaldığı ve bunun daha düşük iç ortam havası sıcaklığına neden olduğu ortaya çıkmıştır

INVESTIGATION OF THE EFFECT OF THE ROOF GEOMETRY ON BUILDING THERMAL BEHAVIOUR

Main objective of this study is to investigate effect of the roof geometry on indoor air conditions in terms of energy efficiency in summer. Harran’s conical roofed building has for this purpose been compared with flat roofed building of equivalent thermo-physical properties, base area and volume. Three dimensional CFD simulations using the low-Reynolds number modeling (LRNM) and standard turbulence models are performed. The effect of roof geometry on natural ventilation is investigated. Cross ventilation flow rates and convection heat transfer coefficients for these two roof types are evaluated for this purpose. Cross ventilation flow rate for the house with conical roof is found to be 8% higher than that of the flat one. The result of the numerical analysis reveals as well that the conical roof transfers 30% less heat to interior side for a representative summer day, resulting in lower indoor air temperature in the house

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