Two-phase hydrodynamic experiments with axial flow through seven-rod clusters

The steam volume fraction of a two phase mixture was measured in the low quality and low mass velocity region, as the fluid flowed upward under atmospheric pressure in 4-rod and 7-rod bundle geometries of triangular lattice (9.5mm O.D. and 1m long, 1.37 and 1.79p/d ratio).The experiments were performed with use made of a capacitance-type void meter described in previous papers, and by supplying various heat inputs into each rod heater.The results indicate that:(1) In the bubble flow region, a significant peaking in void fraction was observed in the transition to slug flow in all the experimental runs. This is probably related to the effects of turbulent interchonge and diversion cross-flow between adiacent subchannels, under conditions of two phase flow.(2) In the slug flow and annular flow regions with large disturbance waves, 4-rod bundle data were 5% lower than those in circular tube and concentric annulus, and 7-rod bundle data 10% lower. These results can be explained by Griffith's(3) correlation with bubble rising velocity, in which channel geometries are considered. Taking account of channel geometry, the authors' correlation proposed in the previous paper is also valid in predicting the void fraction in rod bundle geometries.

岐美格

Papers

524. 二相流の蒸気ボイド率に関する研究,(iii)

岐美 格

Papers

524. 二相流の蒸気ボイド率に関する研究,(iii)

岐美格