In order to investigate the effects of particle properties, including parti
cle shape, on packing characteristics of particles with tapping, changes in
the void fraction epsilon in a tapping particle bed were measured using so
me materials differing in particle shape, size dp and density p. The partic
le shapes were characterized by image analysis of random-oriented particles
and evaluated by a pair of shape indices, circularity <(<phi>)over bar> an
d smoothness <(<zeta>)over bar>. As a result, it was confirmed that changes
in the void fraction with tapping number n can be given by a simple equati
(epsilon - epsilon (f))/(epsilon (0) - epsilon (f)) = exp(-kn(q)).
Furthermore, the effects of particle properties <(<phi>)over bar>, <(<zeta>
)over bar>,(dp) over bar and rho on the initial and final void fractions so
and sc in a packed bed, and on the parameters k and q were clarified by mu
ltiple regression analysis of the experimental results.