Mass Transfer in Annular, Two-Phase Flow

摘要

The report discusses an experimental investigation of the mass transfer (evaporation) occurring during the annular, two-phase flow of air and water in a vertical pipe. Measurements are made of the mass transfer (evaporation) occurring during the annular, two-phase flow of air and water in a vertical pipe. Measurements were made of the mass transfer rate and the surface characteristics of the air-water interface as a function of the following flow parameters: water Reynolds number (23 to 1350), air inlet temperature (110 to 350F), and test section length (8 to 40 in.). All experiments were conducted at an air velocity of 48 fps in 1.5 in. I. D. glass test sections. The mass transfer rate was determined by measuring the increase in the specific humidity of the air stream as it passed through the test section. The surface characteristics (liquid film thickness, wave velocity, and surface area) were measured employing a light absorption technique. The mass transfer data were correlated satisfactorily by the equations for the local heat and mass transfer. (Author)