Expansion of Multi-Purpose Steam Facility and Application to Acoustic Resonance in a Closed Side Branch Investigating Effects of Static Pressure Under Wet Steam Flow

Abstract

Flow-induced acoustic resonances in piping with closed side branches or T-junctions are one of the phenomena causing severe structural vibration and fatigue damage of the piping and components in many engineering applications such as power plants. Practical piping systems of power plants often have a steam flow, and moreover, the steam state can be not only dry steam but also wet steam. From our previous experiments under low-pressure dry and wet steam flows using a single side branch, higher acoustical damping was confirmed under wet steam than that under dry steam, which is considered to be caused by the existing liquid phase. Although the static pressure in practical steam piping is often higher than that in our previous experiments, the effects of the static pressure on acoustical damping under a wet steam flow have not been clarified. Thus, we constructed a new test facility that can be used to perform continuous flow test under dry and wet steam flows with higher pressures than our previous test facility. In this paper, we give an overview of the new steam test facility and some experimental results for the acoustic resonance in a single side branch under higher-pressure dry and wet steam flows than those in our previous studies, using the new facility to investigate and evaluate the effects of the static pressure.