  Quenched or frozen-in structural disorder is ubiquitous in real experimental
systems. Much of the progress is achieved in understanding the phase separation
of such systems using the diffusion-driven coarsening in Ising model with
quenched disorder. But there is a paucity of research in the phase separation
kinetics in fluids with quenched disorder. In this paper, we present results
from a detailed Molecular dynamics simulation, the effects of randomly placed
localized impurities on the phase separating kinetics of binary fluid mixture.
Two different models are offered for representing the impurities. We observe a
dramatic slowing down in the pattern formation with increasing impurity
concentration. This sluggish domain growth kinetics follows power-law with a
disorder-dependent exponent. The correlation function and structure factor show
a non-Porod behavior, indicating the roughening of domain interfaces. We have
also studied the effect of quenched disorder on the aging dynamics by
calculating the two-time order parameter auto correlation function and find
that the Fisher and Huse scaling law holds good in presence of quenched
disorder.
