Oğuz ŞİMŞEK, M. Sami AKÖZ, N. Göksu SOYDAN

Kritik Üstü Açık Kanal Akımının Detached Eddy ve Large Eddy Simülasyon ile Sayısal Modellenmesi

Kritik üstü açık kanal akımının üç boyutlu sayısal analizi, sonlu hacimler yöntemine dayalı ANSYS-Fluent ile yapılmıştır. Sayısal hesaplamalarda türbülanslı akımın karakteristiklerinin belirlenmesinde Large Eddy ve Realizable k-? tabanlı Detached Eddy Simülasyonu kullanılmıştır. Sayısal hesaplamalarda su yüzü profili, Akışkan Hacimleri Yöntemi ile elde edilmiştir. Kritik üstü akımın hız alanı Lazer Doppler Anemometresi kullanılarak ölçülmüştür. Sayısal modellerden elde edilen akım hızları ve su yüzü profilleri deneysel ölçümlerle karşılaştırılmış, Detached Eddy Simülasyon modelinin hız alanının hesaplanmasında ve su yüzü profilinin belirlenmesinde Large Eddy Simülasyon modeline göre daha başarılı olduğu görülmüştür

Numerical Modeling of Supercritical Open Channel Flow with Detached Eddy and Large Eddy Simulation

Three-dimensional numerical analysis of supercritical open channel flow is performed by ANSYS FLUENT-based on the finite volume method. In the numerical analysis of supercritical turbulent flow, Large Eddy Simulation and Detached Eddy Simulation based on the Realizable k- turbulence models are used in order to determine turbulence characteristics. The free surface profile is computed using Volume of Fluid method. The velocity field of supercritical open channel flow is measured using Laser Doppler Anemometry (LDA). Computational results for velocities and free surface profiles are compared with measured data. Comparisons show that the Detached Eddy Simulation model is more successful than Large Eddy Simulation in predicting the velocity field and free surface profiles

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