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Parametrisation in Dissipative Particle
Dynamics: Applications in Complex Fluids
Estela Mayoral-Villa and Eduardo Nahmad-Achar
Abstract A brief overview of mesoscopic modelling for neutral and electrostatically
charged complex fluids via Dissipative Particle Dynamics (DPD) is presented, with
emphasis on the appropriate parametrisation and how to calculate the relevant para-
meters for given realistic systems. DPD is a technique that consists of carrying out a
coarse-graining of the microscopic degrees of freedom and it is highly dependent on
parameters describing the different kinds of force fields and the parametrisation. For
this reason, we present here a revision of DPD parametrisation together with applica-
tions and comparisons with experimental results. The dependence on concentration
and temperature of the interaction parameters for electrostatic and non-electrostatic
systems is also considered, as well as some applications in complex fluids.
1 Introduction
In a colloidal dispersion, the stability is governed by the balance between Van der
Waals attractive forces and electrostatic repulsive forces, together with steric mech-
anisms. Being able to model their interplay is of utmost importance to predict the
conditions for colloidal stability, which in turn is of major interest in basic research
and for industrial applications.
Complex fluids are composed typically at least of one or more solvents, polymeric
or non-polymeric surfactants, and crystalline substrates onto which these surfac-
tants adsorb. Neutral polymer adsorption has been extensively studied using mean-
field approximations and assuming an adsorbed polymer configuration of loops and
tails (de Gennes 1979 , 1981 , 1982 ; Méndez et al. 1998 ). Different mechanisms of
 
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