Naslov
Validation of the rans turbulence model for cfd simulations of the Francis turbine

Autori
Mijalić, Nikola

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Eyec Monograph / - , 2019, 193-201

Skup
8th European Young Engineers Conference

Mjesto i datum
Varšava, Poljska, 8-10.04.2019

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Francis turbine, power, k-ε, k-ω, vortex rope

Sažetak
Cfd simulations in present time are most important part of designing of turbine components, and also become very powerful tool to reduce product development cycle. Flow through high head Francis turbine installed in Hydro Power Plant (hpp) Dubrovnik (Croatia) is considered. In this paper validation of experimental results for efficiency and power was made. Two Francis turbines with 126 MW power each are installed in hpp Dubrovnik. Geometry of the spiral casing, guide and stay vanes, runner and draft tube are reconstructed using 3d cad software Solidworks. Simulation was done for three different operational points pl (Partial Load), bep (Best Efficiency Point), and hl (High Load) using the experimental results from laboratory. In this paper results are compared for three different k-ε variants (Standard, rng, Realisable), and standard k-ω for the same computational set up. Simulation is made for full scale model with frozen rotor approach with approx. 24 million finite volumes. The cfd results for the turbine power and efficiency confirmed the experimental ones at design flow and off-design conditions as well. Realizable k-ε had best results for this kind of flow and computational set up. For pl is shown flow deflection in one side of draft tube, and vortex rope. For hl vortex direction at the draft tube inlet is different than for pl. The opinion and one solution for possible flow improvements in the draft tube has been given. Recommendations and guidelines for next simulations has been given

Izvorni jezik
Engleski

Znanstvena područja
Strojarstvo

POVEZANOST RADA