Development of Enhanced Rifled Tube for Vertical Water Wall Boilers

Abstract

The rifled tubes which have high-cooling capability are adopted for vertical furnace water wall tubes of USC sliding pressure operation once-through boiler. To improve the boiler performance and reliability, it is effective for lowering mass velocity of furnace tube inside. In such case, rifled tubes are required to suppress the heat transfer deterioration phenomenon at supercritical pressure and also DNB (Departure from Nucleate Boiling) at subcritical pressure. In this research, we first screen and developed the rifled tube geometry by re-examining the past experimental results and performing CFD analysis. Finally, we determine new rifled tube geometry by experimental verification of its performance.