M. Ali İSPİR, M. Salih KIRKGÖZ, VEYSEL GÜMÜŞ

Yavaş Değişen Kritik-Altı Açık Kanal Akımının k-? Türbülans Kapatma Modelleri ile Sayısal Hesabı

Yavaş değişen kritik-altı açık kanal akımının (M1 profili) hız alanı, Lazer Doppler Anemometresi (LDA) ile ölçülmüş ve aynı deney koşullarındaki akımlar için, temel denklemler, sonlu hacimler yöntemine dayalı ANSYS-Fluent paket programı ile çözülmüştür. Sayısal hesaplamalarda, Standard k-, Renormalization-group k-? ve Realizable k-? türbülans kapatma modelleri kullanılmış, su yüzü profili VOF yöntemi ile hesaplanmıştır. Sayısal modellerden elde edilen akım hızları deneysel ölçümlerle karşılaştırılmıştır. Farklı türbülans modellerinin deneysel olarak doğrulanması amacıyla yapılan karşılaştırmalarda, Realizable k-? türbülans modelinin, hız alanının hesaplanmasında, kullanılan üç model arasında en başarılı olduğu görülmüştür.

Numerical Analysis of Gradually Varied Subcritical Open Channel Flow Using k-? Turbulence Closure Models

The velocity field of gradually varied subcritical open channel flow (M1 profile) is measured using Laser Doppler Anemometry (LDA). Basic equations of the problem are solved by ANSYS-Fluent program package, using finite volume method, for the flow case having the same experimental conditions. In the numerical simulations, Standard k-?, Renormalization-group k-? and Realizable k-? turbulence closure models are used, and the flow profile is computed using VOF method. Computational results for velocities are compared with measured data. Experimental validations of the turbulence models show that, Realizable k-? turbulence model, among the three, is in general the most successful one in predicting the velocity field of the present flow case.

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