Martí-Franquès COFUND Fellowship Programme

2020MFP-COFUND-15

Josep Bonet Avalos

josep.bonet@urv.cat

Allan D. Mackie

allan.mackie@urv.cat

URV

Nanoscience, Materials and Chemical Engineering

Particulate models for fluid mesoscopic simulations

Mesoscopic heat transport can be found in miniaturized systems such as molecular motors, microelectronic devices, but also in reactive fronts and interfaces. Large temperature gradients (10E6-10E8 K/m) may induce strong couplings between non-equilibrium processes which are of paramount importance in the understanding and the modelling of energy transfer at the nano-scale [1].
The Lagrangian description of fluid dynamics and heat transport is particularly useful when free and mobile interfaces are present [2]. Bottom-up methods, such as the Dissipative Particle Dynamics with energy conservation (DPDE), are suitable for coarse-graining from molecular simulations. DPDE was introduced by the URV team [3], and has been recently extensively applied [4]. At present, a generalised DPDE can describe microscopically complex systems [5].
The main objective of this thesis is to propose an analysis of the heat transport in systems of interest, using the Generalised DPDE model. Several fundamental questions need to be solved, involving the formulation of fluctuating thermodynamics of smalls systems as well as the impact of the coarse-graining from direct molecular simulations [6]. Such a scale analysis should provide the variation of the model parameters, for both reversible as well as dissipative interactions, as functions of the coarse-graining, from low levels near the molecular world dominated by fluctuations, to large coarse-graining levels, where the fluctuations are subdominant. This approach will provide the lacking crossover between molecular simulations, the generalised DPDE mesoscale dynamics and the macroscopic SPH for fluid dynamics.

[1] G. Casati, Nature Nanotechnology 2, 23 (2007); M. Hu, et al., Appl. Phys. Lett. 95, 151903 (2009); H. Acharya, et al., Industrial & Engineering Chemistry Research 51, 1767 (2012).
[2] J. J. Monaghan, Rep. Prog. Phys. 68, 1703 (2005); A. Colagrossi, D. Durante, J. B. Avalos, A. Souto-Iglesias, Phys. Rev. E 96 (2017), 023101, doi:10.1103/PhysRevE.96.023101; J. B. Avalos, M. Antuono, A. Colagrossi, A. Souto-Iglesias, Phys. Rev. E 101 (2020), 013302, doi10.1103/PhysRevE.101.013302
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Ethics: This project does not involve ethical aspects.

Workplace location: Campus Sescelades, Tarragona

27103.20 €

Full time

37.5 hours a week

15 March 2021