Experimental study of the effect of drainage hooks on performance for wave-type vane separators of steam-water in PWR MSR

Extracting liquid water from the steam-water mixture by wave-type vanes is a key process in the moisture separator reheater (MSR) of pressurized water reactors (PWRs), which is essential to ensure turbine safety by reducing the water erosion damage and improve the relative internal efficiency of the turbine. Moreover, higher critical velocity of wave-type vanes, at which re-entrainment occurs, allows for smaller MSR equipment volume or a design with a significant margin for mass flow rate. Therefore, the moisture carryover, the pressure drop, and the critical velocity are the primary focus parameters in the development of wave-type vanes in MSR. In this work, two different drainage hook structures based on the same main wave-type vane were developed. Steam-water experiments with wave-type vanes in a dryer model under actual operating conditions for MSR were conducted to identify the drainage hook structure with the better separation characteristics. Experimental results on the moisture carryover, pressure drop, and the critical velocity were discussed to investigate the effect of different drainage hooks on separation characteristics. Under MSR operation conditions, the wave-type vane II exhibited lower pressure drop and higher separation efficiency across a broad range, making it a highly successful product recommended.