The angular void fraction distribution in randomly packed fixed beds o
f uniformly sized spheres in cylindrical containers is analyzed by a n
ondestructive method where the center coordinates of specially prepare
d spheres are experimentally obtained using X-ray radiography and the
angular void fraction distribution is determined geometrically from th
ese center coordinates. The geometrical solution for the local angular
void fraction is determined by dividing the packed bed of uniform sph
eres into a large number of identical wedge-shaped segments. The local
angular void fraction in each wedge-shaped segment is expressed in te
rms of the solid segments coming from each sphere. The angular void fr
action distribution is obtained from the local angular void fractions
and their angular positions in the cylindrical container. The angular
void fraction distribution is presented for four different diameter as
pect ratios, D/d, ranging from 2.02 to 7.99. The height aspect ratio,
H/d, of each cylindrical container is approximately 7.84. The data sho
w that there is a linear relationship between the mean angular void fr
action and the mean overall void fraction. For diameter aspect ratios
greater than 6.0 the two mean void fractions are essentially the same.
An empirical correlation is presented which accurately predicts the m
ean angular void fraction as a function of the mean overall void fract
ion for packed beds with diameter aspect ratios ranging from 2.02 to 7
.99.