Research on drum feedwater distribution style of sub-critical pressure natural circulation boiler

The paper develops a down-comer feed style (DFS) of drum feedwater distribution of natural circulation boiler based on the study of working process in the drum, which can greatly release the drum metal thermal stress by balancing the temperature field of drum wall. The characteristics of the DFS compared to the normally used pressure distribution mode at present are discussed in detail. The paper analyzes the hydraulic characteristics after the down-comer feed style is adopted. It is concluded that DFS is safe on circulation and simple in design, and can be widely used in subcritical pressure natural circulation boilers.