Experimental study on interfacial area transport in bubbly two-phase flows

In relation to the development of the interfacial area transport equation, local measurements of the void fraction, interfacial area concentration, in terfacial velocity, and Sauter mean diameter using the double sensor probe method as well as the liquid velocity and turbulence intensity using hotfil m anemometry, were performed extensively for vertical upward bubbly air-wat er flows in a round tube with an inner diameter of 25.4 mm at three axial l ocations of L/D=12.0, 65.0 and 125, and fifteen radial locations from r/R=0 to 6.95. The liquid flow rate and the void fraction ranged from 0.292 m/s to 3.49 m/s and from 3% to 27%, respectively. The data set obtained in this study will eventually be used for the development of reliable constitutive relations which reflect the true transfer mechanisms in bubbly flow system s. (C) 1999 Elsevier Science Ltd. All rights reserved.