EFFECT OF SPOILERS TO PRESSURE DISTRIBUTION ON BUILDING ROOF SURFACES

Bu çalışmada, 15° eğimli beşik çatılı bir bina modelinin çatısı üzerinde emme etkisinin kritik olduğu bölgelere yerleştirilen spoiler benzeri akış yönlendirici elemanların çatı yüzey basınç dağılımları üzerindeki etkileri deneysel olarak incelenmiştir. Rüzgar tüneli test bölgesinde oluşturulan atmosferik sınır tabaka içine yerleştirilmiş bina modelinin çatısı üzerinde, farklı çatı-spoiler açıklıkları ve rüzgar doğrultuları için ortalama ve pik yüzey basıncı ölçümleri yapılmıştır. Çatı ön kenarından ayrılan akış, rüzgar tarafındaki çatı yüzeyinde tutunmuş ve çatı sırtından itibaren tekrar ayrılmıştır. Çatı yüzeyleri üzerindeki en kritik negatif basınçlar ayrılmış akış bölgelerinde oluşmuştur. Çatı kenarı ve çatı sırtı boyunca yerleştirilmiş spoiler benzeri elemanların çatı yüzeylerindeki emme yüklerini azaltmada önemli bir etkiye sahip olduğu görülmüştür. Çatı yüzeylerinde basıncın negatif pik değerler aldığı kritik bölgelere yerleştirilen 1 mm açıklığa sahip spoiler benzeri elemanlar, bu bölgelerde meydana gelen emme yükünü %50 ye varan bir oranda azaltmıştır. Spoiler benzeri elemanların çatı üzerindeki kritik emme yüklerini azaltmada yeni bir teknik olarak kullanılabileceği görülmüştür.

BİNA ÇATI YÜZEYLERİ ÜZERİNDEKİ BASINÇ DAĞILIMINA SPOİLERLERİN ETKİSİ

The effect of spoilers placed on the critical regions of 15 sloped gable roof of a building model on the pressure distributions was experimentally investigated in this study. The values of mean and peak pressure coefficients on the roof of the model placed in simulated atmospheric boundary layer were obtained for a variety of roof-to-spoiler apertures and wind directions. Flow separated from the leading edge of the roof attached on the windward side of the roof and re-separated from the roof ridge. The largest negative pressures on the roof surfaces occurred in the separated flow regions. Spoiler elements placed along the roof edges and roof ridge displayed noteworthy effects in the decreasing of suction loads on roof surfaces. Spoilers located with 1 mm aperture on the roof model decreased the suction loads on those regions up to 50%. It was seen that the spoilers can easily be used to reduce critical suction loads on the roofs as a new novel technique.

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