Two-Phase Air-Water Flow in a Slot-Type Distributor

Abstract

Experimental data have been obtained for two-phase air-water flow through a slot-type distributor. Air and water flow rates through the slot were measured as the pressure drop across the slot was varied for fixed values of the main stream quality, the total mass flux, the slot length, and the slot width. Five different slots were cut in the side of a vertical 1-in internal diameter plexiglass tube and a controlled pressure drop across the slot was used to remove a portion of the main stream. Three slot lengths were used: 1·66 in, 4 in, and 6 in. The mass flux was varied from 200 000 to 500 000 lb/h ft2and the air quality ranged from 0·2 to 0·7 at a system pressure of 50 lb/in2(abs.).The orifice equation employing discharge coefficients was successful for calculating cross-flow rates. Two-phase flow discharge coefficients are correlated as a function of the ratio of slot velocity to mainstream velocity. At low cross-flow velocities or large mainstream velocities the hydraulic resistance to cross-flow increased by as much as an order of magnitude. The axial pressure rise across the slot was also measured for both single-phase air and two-phase air-water flows. Values of the momentum correction factor, which accounts for the diverging stream not leaving at right angles to the main flow channel, were determined.