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V. A. Buryachenko

Publications and source records attributed to V. A. Buryachenko.

3 recordsLinked to original sources

New RVE concept in thermoelasticity of periodic composites subjected to compact support loading

This paper introduces an advanced Computational Analytical Micromechanics (CAM) framework for linear thermoelastic composites (CMs) with periodic microstructures. The approach is based on an exact new Additive General Integral Equation (AGIE), formulated for compactly supported loading conditions, such as body forces and localized thermal effects (for example laser heating). In addition, new general integral equations (GIEs) are established for arbitrary mechanical and thermal loading. A unified iterative scheme is developed for solving the static AGIEs, where the compact support of loading serves as a new fundamental training parameter. At the core of the methodology lies a generalized Representative Volume Element (RVE) concept that extends Hill classical definition of the RVE. Unlike conventional RVEs, this generalized RVE is not fixed geometrically but emerges naturally from the characteristic scale of localized loading, thereby reducing the analysis of an infinite periodic medium to a finite, data-driven domain. This formulation automatically filters out nonrepresentative subsets of effective parameters while eliminating boundary effects, edge artifacts, and finite-size sample dependencies. Furthermore, the AGIE-based CAM framework integrates seamlessly with machine learning (ML) and neural network (NN) architectures, supporting the development of accurate, physics-informed surrogate nonlocal operators.

physics.comp-ph

Modeling of random bimodal structures of composites (application to solid propellants): I. Simulation of random packs

We consider a composite medium, which consists of a homogeneous matrix containing a statistically homogeneous set of multimodal spherical inclusions. This model is used to represent the morphology of heterogeneous solid propellants (HSP) that are widely used in the rocket industry. The Lubachevsky-Stillinger algorithm is used to generate morphological models of HSP with large polydisperse packs of spherical inclusions. We modify the algorithm by proposing a random shaking procedure that leads to the stabilization of a statistical distribution of the simulated structure that is homogeneous, highly mixed, and protocol independent (in sense that the statistical parameters estimated do not depend on the basic simulation algorithm). Increasing the number of shaking has a twofold effect. First, the system becomes more homogeneous and well-mixed. Second, the stochastic fluctuations of statistical parameters (such as e.g. radial distribution function, RDF), estimated by averaging of these structures, tend to diminish.

cond-mat.mtrl-sci

Modeling of random bimodal structures of composites (application to solid propellants): II. Estimation of effective elastic moduli

We consider a linearly elastic composite medium, which consists of a homogeneous matrix containing a statistically homogeneous set of multimodal spherical inclusions modeling the morphology of heterogeneous solid propellants (HSP). Estimates of effective elastic moduli are performed using the multiparticle effective field method (MEFM) directly taking into account the interaction of different inclusions. Because of this, the effective elastic moduli of the HSP evaluated by the MEFM are sensitive to both the relative size of the inclusions (i.e., their multimodal nature) and the RDFs estimated from experimental data, as well as from the ensembles generated by the method proposed. Moreover, the detected increased stress concentrator factors at the larger particles in comparison with smaller particles in bimodal structures is critical for any nonlinear localized phenomena such as onset of yielding, failure initiation, and damage accumulation.

cond-mat.mtrl-sci