Bina Üzerindeki Rüzgar Yüklerinin Farklı Türbülans Modelleriyle Sayısal Olarak İncelenmesi

Yıl 2021, Cilt: 37 Sayı: 2, 356 - 366, 28.08.2021

Hacımurat Demir

Öz

Bu çalışmada, karmaşık geometriye sahip bir bina üzerindeki rüzgar yükü sayısal olarak incelenmiştir. Bina çevresindeki akış yapılarını hız, basınç ve türbülanslı kinetik enerji dağılımları açısından değerlendirmek için tek denklemli Spalart-Allmaras, dört denklemli transition SST ve iki denklemli k-ω SST olmak üzere üç tip RANS modeli simülasyon için kullanılmıştır. Tüm simülasyon durumları için bina yüzeyleri etrafındaki basınç katsayısı (Cp) dağılımlarından binanın batıya bakan cephelerinde pozitif; kuzey, güney ve doğu cephelerinde ise negatif Cp değeri olduğu açıkça görülmüştür. Binanın kuzeydoğusundaki girdap oluşumu neticesinde x/L=0.7 konumundan sonra binanın doğusuna doğru ilerlerken Cp değerinde ani ve dik bir artış olmuştur. Ayrıca, binanın kuzey cephesinde emme etkisinin transition SST türbülans modelinde diğerlerine göre daha duyarlı olduğu görülmüştür. Ek olarak, Spalart-Allmaras için yerel en yüksek Cp değeri (batıya bakan kısımda) 1.364 ve transition SST için maksimum yerel emme (kuzeye bakan kısımda)-0.892'ye eşittir. Binanın doğuya bakan kısmındaki akış resirkülasyon bölgesi, transition SST ve k-ω SST modellerine kıyasla Spalart-Allmaras için en geniş haldedir. Spiral düğümlerin ve semer noktalarının konumlarına bakıldığında, Spalart-Allmaras modeli diğer modellerle (transition SST ve k-w SST) karşılaştırıldığında, oluşan girdabın boyutu açısından ayırt edici bir fark vardır.

Anahtar Kelimeler

Bina aerodinamiği, Rüzgar yükü, Türbülans modeli, CFD

Numerical Investigation of Wind Loads on Building with Various Turbulence Models

Öz

In this study, wind load on a building having irregular geometry was investigated numerically. In order to evaluate flow structures around the building in terms of the distributions of velocity, pressure and turbulent kinetic energy, three types of RANS models including Spalart-Allmaras one-equation, transition SST four-equation and k-ω SST two-equation models were utilized for simulation. It was evidently seen from the distributions of pressure coefficient (Cp) around surfaces of the building that positive Cp value was revealed on the west-facing of the building while north-, south-, and east-facing of the building had negative Cp for all simulation cases. By the virtue of the vortex formation in the northeast of the building, after the position of x/L=0.7 there was an abrupt and steep increment in Cp while on the way to the east of the building. Furthermore, it was seen from northern facing of building that suction effect was more sensitive for transition SST turbulence model compared with the others. Besides, the local highest Cp value (west-facing) was 1.364 for Spalart-Allmaras, and the maximum local suction (north-facing) was -0.892 for transition SST. Flow recirculation zone in the east-facing part of the building was the most extended for Spalart-Allmaras compared to transition SST and k-ω SST models. Looking at the positions of the spiral nodes and saddle points, there was a distinguishable difference when Spalart-Allmaras model was compared to the other models (transition SST and k-w SST) with regard to the size of the vortex formed.

Anahtar Kelimeler

Building aerodynamics, Wind load, Turbulence model, CFD

Kaynakça

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