An analysis and applications of the wave model for longitudinal disper
sion are presented Asymptotic forms of the wave model are considered a
nd analytical solutions of typical linear stationary and nonstationary
problems of chemical reactor engineering interest are obtained and co
mpared to those for the Fickian dispersion model. The wave model leads
to efficient analytical solutions for linear problems, which in princ
iple differ fr-om the solutions of the Fickian dispersion model; only
for slowly varying concentration fields do the solutions of both model
s approach each other. Spatial and rime moments of the concentration d
istribution are obtained for pulse-dispersion problems; the first thre
e spatial moments of the mean, variance, and skewness have exact, larg
e-time asymptotic forms in the case of Taylor dispersion. Old experime
nts that could not be explained with the standard dispersion model are
reconsidered and explained: the change with time of the variance of a
concentration pulse when the flow direction is reversed and the diffe
rence in values of the apparent axial dispersion coefficient and the b
ack-mixing coefficient in a rotating disk contactor: The experimental
determination of model parameters is discussed.