, 28:3
First online:
ارزیابی مدلهای تلاطمی در شبیهسازی اموج تیزایستا در جریانهای فوق بحرانی کانالها
 E. AlamatianAffiliated withDept. of Civil Engineering, Ferdowsi University Email author
 , M. R. JaefarzadehAffiliated withDept. of Civil Engineering, Ferdowsi University
EVALUATION OF TURBULENCE MODELS IN SIMULATION OF OBLIQUE STANDING SHOCK WAVES IN SUPERCRITICAL CHANNEL FLOWS
Abstract
In this article, the twodimensional depthaveraged Saint Venant equations, including the turbulence terms, are solved in a supercritical flow with oblique standing waves, and the effects of several turbulence models on the performance of standing oblique shock waves are investigated. The algorithm applies the finite volume Roe TVD method with unstructured triangular cells. To avoid spurious oscillations at regions where the gradients of the variable are considerable, advanced slope limiter functions are implemented in the numerical algorithm. The effects of bed slope, bed friction and turbulences are considered in the source terms. The bed slope and bed friction terms are computed using the data at the center of each cell. Three depthaveraged turbulence models, including the mixing length,kε, and algebraic stress model (ASM), are used to close the hydrodynamic equations. Some experiments are carried out in the ume of a hydraulic laboratory to examine the behavior of the oblique shock waves downstream of a sidebaffle. The supercritical ow in the channel is then simulated numerically and results are compared with the experimental data. A comparison of the experimental results and numerical predictions confirm the robustness of the numerical model. In particular, implementation of turbulence models improves the results at the shock positions. Moreover, all of the models are able to simulate the vortex next to the baffle successfully. However, the kε model and the ASM demonstrate a stronger vortex pattern. Based on our overall findings, the ASM offer superior results to the other models. The quantitative error analysis confirms this finding as well. Our numerical experiments, however, revealed that amongst the source term components, the negligence of the turbulence terms produces the least relative depth error in comparison with the removal of the bed slope or bed friction terms.
Key words
finite volume method mixing length model kε model algebraic stress model oblique standing waves Title
 EVALUATION OF TURBULENCE MODELS IN SIMULATION OF OBLIQUE STANDING SHOCK WAVES IN SUPERCRITICAL CHANNEL FLOWS
 Open Access
 Available under Open Access This content is freely available online to anyone, anywhere at any time.
 Journal

Sharif
28:3
 Online Date
 October 2012
 DOI
 10.7603/s4035401200038
 Online ISSN
 22520600
 Publisher
 Sharif University of Technology
 Additional Links
 Topics
 Keywords

 finite volume method
 mixing length model
 kε model
 algebraic stress model
 oblique standing waves
 Authors

 E. Alamatian ^{(1)}
 M. R. Jaefarzadeh ^{(1)}
 Author Affiliations

 1. Dept. of Civil Engineering, Ferdowsi University, Mashhad, Iran