Numerical Investigation of the Effect of Angle Between Angularly Positioned Two Buildings on Velocity and Pressure Distribution

Öz

In this study, a three-dimensional numerical solution of the flow fields around two angularly positioned building models is realized. In the solutions, Standard k-ɛ, RNG k-ɛ, Realizable k-ɛ and Standard k-ω turbulence models were used comparatively and the performances of turbulence models were investigated for flow around two angularly positioned building models. The performances of turbulence models were examined and when compared with experimental data, it is seen that the results obtained by using the Standard k-ɛ turbulence model has more compatible with the experimental data. For different building angles, the velocity and pressure distributions in the entire flow fields were examined at the Reynolds number 7,7x105 in detail. In the diverging passages, the K values obtained along the center line of the passage between the buildings were obtained much greater than the K values in the converging passages. When the effect of angular change on the pressure coefficient distributions on the surface of building models is examined for the 8 different building configurations where the angle between buildings varies between 0° -180°, it has been seen that the most critical negative pressure coefficient values are affected by the change in angle between the buildings in the diverging and converging building configurations.

Anahtar Kelimeler

• Building aerodynamics
• computational fluid dynamics
• turbulent flow
• turbulence model

Açılı Konumlandırılmış İki Bina Arasındaki Açının Hız ve Basınç Dağılımı Üzerine Etkisinin Sayısal İncelenmesi

Öz

Bu çalışmada, açılı konumlandırılmış iki bina modeli etrafındaki akış alanlarının üç boyutlu sayısal çözümü gerçekleştirilmiştir. Çözümlerde Standard k-ɛ, RNG k-ɛ, Realizable k-ɛ ve Standard k-ω türbülans modelleri karşılaştırmalı olarak kullanılmış ve açılı konumlandırılmış bina modelleri etrafındaki akış için türbülans modellerinin duyarlılıkları araştırılmıştır. Türbülans modellerinin deneysel veriler karşısındaki duyarlılıkları incelendiğinde, Standard k-ε türbülans modelinin kullanılmasıyla elde dilen sonuçların, deneysel verilerle daha uyumlu olduğu görülmüştür. Farklı bina açıları için gerçekleştirilen bu çalışmada, akış alanının tamamına ait hız ve basınç dağılımları Reynolds sayısının 7,7x105 değeri için ayrıntılı olarak incelenmiştir. Genişleyen geçitlerde, binalar arasındaki geçidin merkezi çizgisi boyunca elde edilen K değerleri, daralan geçitlerdeki K değerlerinden çok daha büyük olarak elde edilmiştir. Binalar arasındaki açının 0°-180° arasında değiştiği 8 farklı bina konfigürasyonu için, açısal değişimin bina modelleri yüzeyindeki basınç katsayısı dağılımlarına etkisi incelendiğinde, daralan ve genişleyen bina konfigürasyonlarında, en kritik negatif basınç katsayısı değerlerinin binalar arasındaki açının değişiminden etkilendiği görülmüştür.

Anahtar Kelimeler

• Bina aerodinamiği
• hesaplamalı akışkanlar dinamiği
• türbülanslı akış
• türbülans modeli

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