Önden ve yanal rüzgar şartı altında Ahmed cisminin sayısal incelenmesi

Bu çalışmada Ahmed cismine ait zamana bağlı akış alanı iki farklı arka yüzey eğim açısı için incelenmiştir.Yanal rüzgar şartlarının önden rüzgar şartlarına göre aerodinamik etkilerini nasıl değiştirdiği, 3 boyutlu zamana bağlı akış alanı çözümleri realiable k-? türbülans modeli kullanılarak incelenmiştir. Hesaplanan akış alanı sonuçları deneysel çalışmalar ve daha önce yapılmış sayısal veriler ile karşılaştırılarak doğrulanmıştır. Akış alanına ait genel özellikler ve akış yapılarına ait basınç katsayısı, akım çizgileri, türbülans kinetik enerji ve hız büyüklüğü gibi farklı akış alanı değişkenleri birçok tanımlı düzlem üzerinde tüm sayısal hesaplamalar için gösterilmiştir.

Numerical investigation of headwind and crosswind conditions of Ahmed body

In this study, unsteady incompressible flow field 3D Ahmed body are investigated for two different slantangle. In the case of 3D unsteady flow fields, realiable k-? turbulence model is used to investigate theaerodynamical effects of crosswind conditions over headwind conditions. All numerical results arecompared and validated with experimental measurement and previously conducted numerical studies. Thegeneral nature of the flow field and its structure demostrated by different flow field quantities such aspressure coeeficient, streamlines, turbulence kinetic energy and velocity magnitude along various crosssections were presented for all numerical cases.

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