Experimental study on density wave oscillation of parallel rectangular channels

Experimental study was performed on Density Wave Oscillation (DWO) with two parallel rectangular channels, which has 25 mm x 2 mm cross section and 1000 mm heated length. the results show that flow was stable while mass velocity, pressure, and inlet subcooling were increased. Period of oscillation were shortened if mass velocity was increased or inlet subcooling was reduced. Pressure has little effect on period of DWO in this research. As for analysis results from rectangular channel and rod tube, dimensionless subcooling number Nsub and phase change number Npch were adopted. The comparison indicates that both rod tubes and rectangular channels fit close with each other well. This proves characteristic of DWO in rod tubes and rectangular channels are almost the same. (authors)