DEVELOPMENT OF TECHNOLOGIES ON INNOVATIVE-SIMPLIFIEDNUCLEAR POWER PLANT USING HIGH-EFFICIENCY STEAMINJECTORS (7) TWO-PHASE FLOW STRUCTURE IN CENTRALSTEAM JET INJECTOR

摘要

Experimental studies on turbulence structure inrnannular two-phase flow were carried out concernedrnwith the central steam jet injector for a nextrngeneration nuclear reactor. In the central steam jetrninjector, steam/water annular two-phase flow isrnformed at the mixing nozzle. To make an appropriaterndesign for high-performance steam injector system, itrnis very important to accumulate the fundamental datarnof the thermo-hydro dynamic characteristics ofrnannular flow in the steam injector system. Especially,rnthe turbulence modification in multi-phase flow duernto the interactions between two-phases is one of thernmost important scientific issue and has attractedrnresearch attention. In this study, the behavior of thernliquid film moving with wavy interface and thernresultant gas-phase turbulence modification due to thernphase interaction were investigated. The behavior ofrnthe interfacial waves in the liquid film flow such asrnthe ripple or disturbance waves were observed byrnusing high-speed video camera system and digitalrncamera and made clear the interfacial velocity, thernspecial structure of the interfacial waves. Thernmeasurements for gas-phase turbulence werernprecisely performed by using the constant temperaturernhot-wire anemometer, and made clear the velocityrnprofiles, fluctuation velocity profiles in gas-phasernturbulence flow passing through the throat section.rnThe measurements for liquid film thickness by thernelectrode needle method were also performed.