CFD Simulations AC6-15
Vortex ropes in draft tube of a laboratory Kaplan hydro turbine at low load
Application Area 6: Turbomachinery Internal Flow
Application Challenge AC6-15
CFD Simulations
Solution Strategy
The computations reported here were performed with the ANSYS-FLUENT (Manual ANSYS Fluent v.17.1) code using the two built-in popular linear eddy-viscosity models (k-ω-SST and realizable k-ε), the Re-stress LRR model (Launder, Reece, & Rodi, 1975) with the linear pressure strain and wall-echo terms, and a DES (based on Menter?'s k-ω SST model). In parallel, for reference, LES with the WALE subgrid-scale viscosity model (Nicoud & Ducros, 1999) was carried out on finer grids.
The high-Re-number realizable k-? model and the basic RSM were solved using the standard wall functions. A test with the enhanced wall treatment and the non-equilibrium wall function available in the FLUENT code produced no significant differences in the results. For the k?? SST model we used the enhanced-wall-treatment ?-equation model (EWT-?) (ANSYS Fluent v.17.1 Theory Guide).
Contributed by: A. Minakov [1,2], D. Platonov [1,2], I. Litvinov [2], S. Shtork [2], K. Hanjalić [3] —
[1] Institute of Thermophysics SB RAS, Novosibirsk, Russia,
[2] Siberian Federal University, Krasnoyarsk, Russia,
[3] Delft University of Technology, Chem. Eng. Dept., Holland.