  Our interest lies in exploring the ability of a coupled nonlocal system of
two quasilinear parabolic partial differential equations to produce phase
separation patterns. The obtained patterns are referred here as morphologies.
Our target system is derived in the literature as the rigorous hydrodynamic
limit of a suitably scaled interacting particle system of Blume--Capel--type
driven by Kawasaki dynamics. The system describes in a rather implicit way the
interaction within a ternary mixture that is the macroscopic counterpart of a
mix of two populations of interacting solutes in the presence of a background
solvent. Our discussion is based on the qualitative behavior of numerical
simulations of finite volume approximations of smooth solutions to our system
and their quantitative postprocessing in terms of two indicators (correlation
and structure factor calculations). Our results show many similar features
compared to what one knows at the level of the stochastic Blume--Capel dynamics
with three interacting species. The properties of the obtained morphologies
(shape, connectivity, and so on) can play a key role in, e.g., the design of
the active layer for efficient organic solar cells.
