Optical coarse droplet measurement and wet loss analysis on the wet air flow through the subsonic blade cascade channel

In order to understand the details of the mechanism of the occurrence of wetness loss between blade rows, the blades of an HP nuclear turbine were modeled in an atmospheric subsonic wind tunnel, and a flow field with wet loss was analyzed in its totality using a three-hole Pitot tube and Phase Doppler Particle Analyzer (PDPA) system. In the secondary flow loss region and the end wall loss region, a significant increase in pressure loss was confirmed under wet conditions. Analysis by measurement and the Eulerian-Lagrangian coupled solver showed that these loss increases can occur due to the agitation of water droplets and water films in the passage vortex or corner vortex. Finally, this report contains a breakdown of profile loss, thermodynamic loss and acceleration loss of the wet air flow through the sub-sonic blade row.