Coarse-grained approach, mesoscale

An alternative mesoscale approach for high-level molecular modeling of hydrated ionomer membranes is coarse-grained molecular dynamics (CGMD) simulations. One should notice an important difference between CGMD and DPD techniques. CGMD is essentially a multiscale technique (parameters are directly extracted from classical atomistic MD) and it... 

In this chapter, we have discussed only a few examples of mesoscale phenomena in fluids, for which the methods of meso-thermodynamics appeared to be applicable. However, since coarse-grained models of meso-thermodynamics, such as the Landau-Ginzburg local Helmholtz energy, demonstrate a high degree of universality, associated with the meso-scale structure, an extension of this approach to a broader variety of phenomena is very promising. 

The phase morphology obtained for a simplified DPD model of the PVBPA/PEEK copolymer depends on the way the coarse-grained model is set up. Mutliscale approach was indeed helpful to find the parameters for the mesoscale DPD simulations. 

When hydrodynamic effects are not expected to be important, it is often convenient to simulate without explicit solvent molecules. This approach can stUl be justified even when hydrodynamic flow becomes relevant, but solvent-related degrees of freedom have to be incorporated on a certain coarse-grained level. To reproduce hydrodynamic effects in the continuum limit, mesoscale hydrodynamic techniques... 

In order to overcome these difficulties, considerable effort has been devoted to the development of mesoscale simulation methods such as Dissipative Particle Dynamics [1-3], Lattice-Boltzmann [4-6], and Direct Simulation Monte Carlo [7-9]. The common approach of all these methods is to average out irrelevant microscopic details in order to achieve high computational efficiency while keeping the essential features of the microscopic physics on the length scales of interest. Applying these ideas to suspensions leads to a simplified, coarse-grained description of the solvent degrees of freedom, in which embedded maaomolecules such as polymers are treated by conventional molecular dynamics simulations. 

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