Paying attention to the discrepancy between available data, probably due to the uncertainty in void fraction, the entrance end effect and characteristics of the experimental method, newexperimental results were obtained for air-water flow in 65.8 and 122 mmφ. columns packed with glass spheres of six different sizes between 2.59 and 24.3 mm0.The two-phase pressure loss based on an energy (not momentum) balance was correlated in terms of Lockhart-Martinelli parameters as follows :
φ_l=1.30+1.85χ^-0.85, 0.1<χ<20
The total liquid holdup Ri was determined by weighing the excess weight of bed in operation over the dry column. The result was dependent on the specific surface area of the bed a_s and correlated by
R_l=0.40 a_s^1/3χ^0.22 (a^s in mm^-1)
The present result on total holdup was higher than available results obtained by quickclosing valve, which measured probably the operating holdup. Data of void fraction for spherical packings are appended and the differences in void fraction and its reproducibility due to packing procedure are noted.