Analysis of Two- Dimensional Flow over Standard Ogee Spillway Using RNG Turbulenc Model

In the analysis and design of hydraulic structures it is necessary to precisely determine all flow parameters . Flow analysis using laboratory experiments usually involves considerable time and cost requirements. Nowadays, availability of computational fluid dynamic (CFD) programs and powerful computers has resulted in increasing usage of numerical methods of flow over standard ogee spillway. Navier – Stockes equations and Reynolds Average Navier – Srockes (RANS) equations were used to analyze the flow over standard ogee spillway. To calculate Reynolds stresses, Renormalization Group Theory (RNG) k-e turbulence model was used. Flow was analyzed for different head values and flowrate and velocity at different sections of spillway were calculated and compared with experimental results. Results showed that the numerical method could properly describe flow over the standard ogee spillway. Results obtained from analysis of flow have been presented in the form of non-dimensional values of the flowrate , depth and velocity for different heads and sections of the spillway . Comparison of results of numerical analysis for flowrate with results presented by Utah Water Research Laboratory (UWRL) showed good agreement for moderate to high heads. Comparison of computed velocity with URWL results showed good agreement for heads greater than one-third of the design head, but did not give accurate results for smaller heads.

کلیدواژه ها:

Ogee Spillway ، Numerical Methods ، Turbulence Model ، Reynolds average Navier-Stockes (RANS) equations