GAS-LIQUID 2-PHASE FLOW IN SYMMETRICALLY DIVIDING HORIZONTAL TUBES

The time-averaged void fraction, pressure drop and flow regime transition behavior of horizontal air-water two-phase flows is studied experimentally and numerically for 2-cm-inner-diameter tubes with various flow dividing junctions at its end. The time-average void and pressure drop behavior along the channel is simulated using a two fluid separated flow model. The results show that two-phase behavior (flow regime, void fraction, and pressure drop) is affected strongly by the presence of a flow division in the system. These effects extend far upstream of the junction for low-momentum flows and far downstream for high-momentum flows. Both numerical and experimental results show that there occurs a large increase in void just downstream of the junction owing to the halving of the fluid volume flow rates and the liquid deceleration.