Geniş Başlıklı Savak Akımının Deneysel ve Sayısal Modellenmesi

Year 2011, Volume: 26 Issue: 2 - Volume: 26 Issue: 2, 33 - 45, 25.07.2016

Harun Bal M.Salih Kırkgöz Veysel Gümüş

Abstract

Geniş başlıklı savak üzerinden geçen akımın hız alanı, Lazer Doppler Anemometresi (LDA) ile ölçülmüş ve aynı deney koşullarındaki akım için, temel denklemler, sonlu hacimler yöntemine dayalı ANSYSFluent paket programı ile çözülmüştür. Sayısal hesaplamalarda, Standart k- ε, RNG k- ε, Realizable k-ε, Modified k- , SST ve RSM türbülans kapatma modelleri kullanılmış, su yüzü profili VOF yöntemi ile hesaplanmıştır. Sayısal hesaplamalardan elde edilen akım hızları ve su yüzü profilleri deneysel ölçümlerle karşılaştırılmıştır. Türbülans modellerinin deneysel olarak doğrulanması bağlamında yapılan karşılaştırmalarda, SST türbülans modelinin, hız alanı ve su yüzünün hesaplanmasında, kullanılan altı model arasında en başarılı olduğu görülmüştür

Keywords

Geniş başlıklı savak, LDA, Sayısal model, VOF, Hız profili

Experimental and Numerical Modeling of Flow over a Broad-Crested Weir

Abstract

The velocity field of flow over a broad-crested weir is measured using Laser Doppler Anemometry (LDA). Basic equations of the present problem are solved by ANSYS-Fluent package program, using finite volume method, for the flow case having the same experimental conditions. In the numerical simulations, Standard k- ε, RNG k-ε, Realizable k-ε, Modified k-, SST and RSM turbulence closure models are used, and the flow profile is computed using VOF method. Computational results for velocities and flow profiles are compared with measured values. Experimental validations of the turbulence models show that, SST turbulence model, among the six, is in general the most successful one in predicting the velocity field and the free surface of the present flow case

Keywords

Broad-crested weir, LDA, Numerical model, VOF, Velocity profile

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