Numerical Simulation of Turbulent Sodium Flows in Subchannels of an LMFBR Fuel Subassembly Project Representative
نویسندگان
چکیده
Isothermal and non-isothermal LES (Large Eddy Simulation) has been carried out to fully reproduce the characteristics of the flow field in eccentric annular channels, and rod bundles. The numerical approach is based upon boundary fitted coordinates and a fractional step algorithm; a dynamic Sub Grid Scale (SGS) model suited for this numerical environment has been implemented and tested for both isothermal and buoyancy driven flows inside annular channels with different eccentricities. The agreement with experiment and DNS/LES results has been found good in both isothermal and buoyancy driven flows in annulus channels. Instantaneous flow field presented large scale coherent structures in the streamwise direction at low Reynolds numbers, while these are absent or less dominant at higher Reynolds, thus reproducing successfully the global pulsation phenomena in tight lattice rod bundles of LMFBRs.
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