棒束通道内定位格架的两相流动局部阻力实验研究

在常温、常压条件下,对竖直3×3棒束通道内定位格架的单相及两相局部阻力特性进行了实验研究。单相流动实验时,水雷诺数的变化范围为290~18 007;两相实验时,气相、液相表观速度变化范围分别为0.013~3.763m/s和0.076~1.792m/s。利用单相实验数据得到的定位格架局部阻力系数计算关系式,用两相实验数据对均相流模型中8种不同的两相等效黏度计算方法进行了评价。Rel9 000时,Dukler模型的预测效果最好;Rel≥9 000时,McAdams计算方法预测效果最好;基于所有数据,Dukler模型的计算值与实验值吻合最好,平均相对误差为29.03%。考虑了质量含气率、两相雷诺数及气液相密度的影响,对Rel9 000时的实验数据进行了拟合,得到的经验关系式的计算值与实验值符合较好。

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 3×3 rod 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 290-18007. For the case of two-phase flow, the ranges of gas and liquid superficial velocities were 0.013-3.763 m/s and 0.076-1.792 m/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 Re_l<9000 while McAdams correlation is the best one for Re_l≥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 Re_l<9 000 by considering mass quality, two-phase Reynolds number and liquid and gas densities, resulting in a good agreement with the experimental data.