Experimental research on the characteristics of steam jet condensation in subcooled water through a double-hole nozzle in one direction

Highlights: • The nozzles of the four spray arms similar to the actual ADS application are used. • The mutual shielding effect in the double-hole spraying process is defined. • The simplified lumped condensation model for the double-hole steam jets is proposed. • The double-hole condensation HTC ranges are estimated. In this study, a series of experiments were conducted to examine the characteristics of steam jet condensation through a double-hole nozzle under different test conditions. Thermocouple matrix and high-speed camera were employed for measuring the key thermal and flow parameters. The results revealed when the water temperature approached the saturation temperature, the two steam plumes were combined into one steam plume, and mutual shielding effect was observed between the two steam plumes. Meanwhile, the length of the combined steam plume was longer than that of single-hole steam plume under the same condition. Besides, the experimental results revealed that the average heat transfer coefficient (HTC) was in the range of 0.5 to 2.0 MW/m² K. This indicates that the HTC of double-hole steam jet is closely related to the water temperature and steam mass flux. Further, the mutual shielding effect of neighboring steam plumes reduced the HTC of DCC.