Research Of Netted Film Type Deaerator Characteristics

The water quality of once-througeh boiler and once-through steam ge-neratrer is high, for its operation features. Then its oxygen level of water is high than conventional power plant. At present, a single low pressure bubble thermal deaerators is not meet it. In addition, considering of space condition, it is valuable to study high-efficency and miniaturized technology of oxygen removal.Base on the result of spray tray deaerator research, the netted film type deaerator was designed by analyzing heat and mass transfer characteristics of deaerator in dissertation. And experimental research was done. The deaeration characteristics of net in deaerator, and the load characteristics of netted film type deaerator were studied. The result of experimental research indicates that net in deaerator improve the mass transfer and deaeration efficiency, and the steady/unsteady operation of this type deaerator is fine.Based on the experiments using self-designing "three-fluids" nozzle, one new type nozzle was designed. The characters of exterior stream of this nozzle were studied by use of numerical simulation, and spraying process was analyzed. Results show that initial velocity of airflow is faster and then jet distance longer before spraying, and diffusion angle of velocity field is smaller. And the static pressure along the axis of exterior stream retains a constant. During spraying process, the coupling between water and air has strong effect on the exterior stream and makes the diffusion angle of velocity field increasing, and then strengthens the entrainment of ambient air. Velocity of airflow along the axis of exterior stream decreases quickly. And velocity of droplets along the axis of exterior stream varies little.