  The relationship between geometric and dynamic properties of fractal-like
aggregates is studied in the continuum mass and momentum-transfer regimes. The
synthetic aggregates were generated by a cluster-cluster aggregation algorithm.
The analysis of their morphological features suggests that the fractal
dimension is a descriptor of a cluster's large-scale structure, whereas the
fractal prefactor is a local-structure indicator. For a constant fractal
dimension, the prefactor becomes also an indicator of a cluster's shape
anisotropy. The hydrodynamic radius of orientationally averaged aggregates was
calculated via molecule-aggregate collision rates determined from the solution
of a Laplace equation. An empirical expression that relates the aggregate
hydrodynamic radius to its radius of gyration and the number of primary
particles is proposed. The suggested expression depends only on geometrical
quantities, being independent of statistical (ensemble-averaged) properties
like the fractal dimension and prefactor. Hydrodynamic radius predictions for a
variety of fractal-like aggregates are in very good agreement with predictions
of other methods and literature values. Aggregate dynamic shape factors and
DLCA individual monomer hydrodynamic shielding factors are also calculated.
