Pressure fluctuation characteristics of complex turbulent flow in a dual elbow with small curvature radius in a three-dimensional layout

Konno, Hiroaki*; Ebara, Shinji*; Hashizume, Hidetoshi*; Yamano, Hidemasa   ; Aizawa, Kosuke 

To clarify the pressure fluctuation characteristics of the coolant in the cold-leg piping of JSFR, a pressure measurement test for a dual elbow piping was conducted. From the results, a prominent peak appeared in a profile of pressure fluctuation PSD obtained at the intrados side of the outlet of the first elbow which also appeared in a single elbow experiment. Differences between the single and dual elbow appeared about a radius and more downstream of the first elbow outlet. It was clarified that this was because of the flow near the inlet of the second elbow was largely bent and given swirling motion by the existence of the second elbow.