A Preliminary Numerical Study on the Performance of Cyclone Separators in Supercritical CO2 Solar Power Plants

Abstract

A combined approach of computational fluid dynamics, the discrete phase model, and the wall erosion model was used to numerically investigate the hydrodynamics, separation efficiency, and erosion rate in cyclone separators for s-CO2 solar power plants. Moreover, the results were compared with those for air and CO2 as carrier phases. The experimental data from the literature were used to validate the numerical model, and it was observed that the simulated gas velocities and wall erosion rate accurately aligned with the experimental measurements. The numerical results reveal that s-CO2 had the largest tangential velocity compared to the other two media; its area-weighted axial velocity of upward flow was the lowest in the middle part of the cyclone body, and varied considerably in the bottom region of the conical section. The particles were all collected at the bottom surface of air and CO2, but the separation efficiency of s-CO2 was 81.51%, due to the poor distribution of the vortex and short circuit. Finally, the erosion rate distribution and averaged surface erosion rate were also analyzed for the three carrier phases.