EXPERIMENTAL INVESTIGATION ON STEAM JET CONDENSATION IN SUBCOOLED WATER THROUGH DOUBLE NOZZLE

Experimental investigation has been conducted to explore the effect of double nozzle on the characteristics of steam jet condensation. The condensation process and jet noise are recorded by high speed camera and hydrophone, respectively. Five typical condensation regimes are identified based on the shape of steam plume. A condensation map suitable for both single nozzle and double nozzle is developed based on steam mass velocity and water temperature. The maximum expansion ratio of steam plume increases with the rise of steam mass velocity and water temperature. The maximum expansion ratio of double nozzle becomes larger than single nozzle as the water temperature increases. The equivalent diameter of steam bubble in condensation oscillation regime increases with the rise of water temperature. The forming frequency of steam bubble decreases with the rise of water temperature. There is no remarkable difference of the steam bubble equivalent diameter between single and double nozzle. However, the steam bubble forming frequency of double nozzle experiments is smaller than single nozzle experiments. The first dominant frequency decreases with the rise of water temperature and it is very close to the steam bubble forming frequency in condensation oscillation regime. The double nozzle can reduce the first dominant frequency about 5% at the steam mass velocity of 400 kg/m(2)s and 15% at the steam mass velocity of 800 kg/m(2)s.