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The present contribution is dedicated to a Discrete Element Method (DEM)-based approach aiming at assessing the thermomechanical behavior of composite materials. Such an approach presents several advantages in comparison to other classical methods as the Finite Element (FE) one. This enables a better description of the multi-scale behavior of the material with the inherent variability related to the microscopic scale. It also gives the possibility to directly access information such strain and stress fields and heat flux density at the scale of the discrete element. In the current work, a focus is done on the thermoelastic properties of a heterogeneous medium composed of a single inclusion. A 2D representative pattern is generated and discretized using a granular packing composed of cylindrical particles in contact point. This is generated using a process based on the Lubachevsky-Stillinger Algorithm (LSA) coupled to a DEM approach based on a smooth formulation. A hybrid-particulate model is considered to model the mechanical behavior of the material. In this approach, the contact between two particles is described by a beam element which models the cohesive link at the microscopic scale. Heat transfer is simulated using an iterative time-dependent scheme based on the Fourier's law and Vorono\"i's mosaics generated from granular packings. A full range of thermoelastic properties are considered in order to investigate several configurations of material from an insulative fibre less resilient than the surrounding matrix to a conductive fibre more resilient than the matrix. Estimated properties are compared to those obtained from other numerical methods such as FE and Fast Fourier Transform (FFT)-based calculations and analytical models. Results highlight the ability of the proposed approach to estimate effective thermoelastic properties. These first results pave the way of interesting insights since taking into account non-linear behaviors, interfacial effects and damaging in the proposed approach can be envisaged in a next future.

Computation, modeling, simulation, numerical methods, multi-scale