Pipe Flow and Pressure Oscillation due to Vapor Condensation in Pool Water

Abstract

An experimental study of pressure oscillation in a single vent tube due to vapor condensation into pool water was performed. The objectives of the work are to establish the character of the dominant frequency and the progression of the pressure wave in the condensation oscillation (CO) -chugging transition region, and to confirm the relationship between vapor velocity and pressure oscillation in chugging. In CO region, most of the pressure wave component had progressive character, and some, a stationary character of resonance in vent tube. In the CO-chugging transition region, the dominant frequency of the progressive wave component increased with vapor mass flow rate and water subcooling temperature. The effects of these parameters on the dominant frequency was explained well by a cylindrical bubble model. In chugging, the maximum vapor velocity was lower than that expected from a simulation model, and the pressure wave had no progressive component.