FLOODING IN GAS-LIQUID COUNTERCURRENT 2-PHASE FLOW IN PARALLEL VERTICAL PIPES

Flow regime transition and pressure drop in gas-liquid countercurrent two-phase flow was studied in three vertical parallel channels. The co nditions for flooding initiation in parallel-channel systems could be predicted well using Imura's correlation for a single channel. After f looding, the flow patterns were different in each channel. A how patte rn classification diagram for the three-channel system was developed b ased on the flow patterns observed under various conditions of gas and liquid flow rates. It was seen from the results of pressure measureme nt in the three-channel system that the maximum pressure developed in each channel had a serious effect on the average pressure in the lower plenum, and that the frictional loss coefficient, estimated from the time-averaged pressure in the lower plenum, could be correlated to the relative gas Reynolds number.