Experimental study on pressure pulse generated by condensing subsonic/supersonic steam jet in a horizontal channel

The direct contact condensation (DCC) of submerged vapor jet in liquid, which has high heat and mass transfer efficiency, is widely applied in nuclear power generation, chemical engineering and aerospace. The pressure pulse generated by hydraulic instability during DCC may create periodical impulsive loads on the solid wall. It is important to evaluate pressure pulse characteristics using a wide range of inlet properties to avoid risky flow pattern regions where pressure pulses are strong. This paper presents an experimental study of the interface dynamics and pressure pulse of DCC using subsonic and supersonic steam jets condensing in water in a horizontal channel. The results reveal that pressure pulses in unstable region are caused by the contraction and expansion of the steam-water interface, while pressure pulses in stable region are caused by Kelvin-Helmholtz (KH) instability. Flow pattern transition is found to affect pressure pulse intensity. Pressure pulse intensity is minimal at the transition between the stable region and unstable region. The correlations of pressure pulse intensity in unstable and stable regions are given, respectively. The results of this study can inform the design, safe operation, and lifespan evaluation of equipment in various industrial applications that involve DCC.