Experimental Study on Local Resistance of Two-phase Flow through Spacer Grid with Rod Bundle

The experimental study on local resistance of single-phase and two-phase flows through a spacer grid in a vertical channel with 3×3rod bundle was carried out under the normal temperature and pressure.For the case of single-phase flow,the liquid Reynolds number covered the range of 290-18 007.For the case of two-phase flow,the ranges of gas and liquid superficial velocities were 0.013-3.763m/s and 0.076-1.792m/s,respectively.A correlation for predicting local resistance of single-phase flow was given based on experimental results.Eight classical two-phase viscosity formulae for homogeneous model were evaluated against the experimental data of two-phase flow.The results show that Dukler model predicts the experimental data well in the range of Re1〈9000 while McAdams correlation is the best one for Rel≥9 000.For all experimental data,Dukler model provides the best prediction with the mean relative error of 29.03%.A new correlation is fitted for the range of Re1〈9000 by considering mass quality,twophase Reynolds number and liquid and gas densities,resulting in a good agreement with the experimental data.