A. Lkouen^1,*, M. Lamrani², A. Meskini¹, A. Khabbazi³

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.8, pp. 2013-2026, 2023, DOI:10.32604/fdmp.2023.026929

Abstract Most of the energy savings in the building sector come from the choice of the materials used and their microphysical properties. In the present study, through numerical simulations a link is established between the thermal performance of composite materials and their microstructures. First, a two-phase 3D composite structure is modeled, then the RSA (Random Sequential Addition) algorithm and a finite element method (FE) are applied to evaluate the effective thermal conductivity of these composites in the steady-state. In particular, building composites based on gypsum and clay, consolidated with peanut shell additives and/or cork are considered. The numerically determined thermal conductivities… More > Graphic Abstract

Guojun Zheng^1,2, Zhaomin Yan¹, Yang Xia^1,2, Ping Hu^1,2, Guozhe Shen^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.3, pp. 1975-1995, 2023, DOI:10.32604/cmes.2022.021415

Abstract Peridynamics (PD) is a non-local mechanics theory that overcomes the limitations of classical continuum mechanics (CCM) in predicting the initiation and propagation of cracks. However, the calculation efficiency of PD models is generally lower than that of the traditional finite element method (FEM). Structural idealization can greatly improve the calculation efficiency of PD models for complex structures. This study presents a PD shell model based on the micro-beam bond via the homogenization assumption. First, the deformations of each endpoint of the micro-beam bond are calculated through the interpolation method. Second, the micro-potential energy of the axial, torsional, and bending deformations… More >

Chih-Wen Chang^*

CMC-Computers, Materials & Continua, Vol.72, No.2, pp. 3231-3245, 2022, DOI:10.32604/cmc.2022.024563

Abstract In this paper, we address 3D inverse Cauchy issues of highly nonlinear elliptic equations in large cuboids by utilizing the new 3D homogenization functions of different orders to adapt all the specified boundary data. We also add the average classification as an approximate solution to the nonlinear operator part, without requiring to cope with nonlinear equations to resolve the weighting coefficients because these constructions are owned many conditions about the true solution. The unknown boundary conditions and the result can be retrieved straightway by coping with a small-scale linear system when the outcome is described by a new 3D homogenization… More >

Yu-Fu Ko^1,* , Jiann-Wen Woody Ju²

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.3, pp. 1305-1328, 2021, DOI:10.32604/cmes.2021.017589

Abstract Higher-order multiscale structures are proposed to predict the effective elastic properties of 3-phase particle reinforced composites by considering the probabilistic spherical particles spatial distribution, the particle interactions, and utilizing homogenization with ensemble volume average approach. The matrix material, spherical particles with radius a₁, and spherical particles with radius a₂, are denoted as the 0^th phase, the 1^st phase, and the 2^nd phase, respectively. Particularly, the two inhomogeneity phases are different particle sizes and the same elastic material properties. Improved higher-order (in ratio of spherical particle sizes to the distance between the centers of spherical particles) bounds on effective elastic properties… More >

Heru Suryanto^1,2,*, Muhamad Muhajir¹, Bili Darnanto Susilo¹, Yanuar Rohmat Aji Pradana¹, Husni Wahyu Wijaya^2,3, Abu Saad Ansari⁴, Uun Yanuhar⁵

Journal of Renewable Materials, Vol.9, No.10, pp. 1717-1728, 2021, DOI:10.32604/jrm.2021.015312

Abstract The microstructure of bacterial cellulose nanofibers (BCNs) film affects its characteristic. One of several means to engineer the microstructure is by changing the BCNs size and fiber distribution through a high-pressure homogenizer (HPH) process. This research aimed to find out the effects of repetition cycles on HPH process towards BCNs film characteristics. To prepare BCNs films, a pellicle from the fermentation of pineapple peels waste with Acetobacter xylinum (A. xylinum) was extracted, followed by crushing the pellicle with a high-speed blender, thereafter, homogenized using HPH at 150 bar pressure with variations of 5, 10, 15, and 20 cycles. The BCNs… More >

Marco Lo Cascio¹, Marco Grifò¹, Alberto Milazzo¹, Ivano Benedetti^1,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.23, No.1, pp. 13-13, 2021, DOI:10.32604/icces.2021.08335

Abstract The Virtual Element Method (VEM) [1] is a recent numerical technique that is capable of dealing with very general polygonal and polyhedral mesh elements, including irregular or non-convex ones. Because of this feature, the VEM ensures noticeable simplification in the data preparation stage of the analysis, especially for problems whose analysis domain features complex geometries, as in the case of computational micromechanics problems [2]. The Boundary Element Method (BEM) [3] is a well-known, extensively used and efficient numerical technique that has been successfully employed for the computational homogenization of materials with complex morphologies [4]. Due to its underlying formulation, the… More >

Jurica Sorić^*, Tomislav Lesičar, Zdenko Tonković

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.3, pp. 915-934, 2021, DOI:10.32604/cmes.2021.014142

Abstract The paper deals with the numerical modelling of ductile damage responses in heterogeneous materials using the classical second-order homogenization approach. The scale transition methodology in the multiscale framework is described. The structure at the macrolevel is discretized by the triangular C¹ finite elements obeying nonlocal continuum theory, while the discretization of microstructural volume element at the microscale is conducted by means of the mixed type quadrilateral finite element with the nonlocal equivalent plastic strain as an additional nodal variable. The ductile damage evolution at the microlevel is modelled by using the gradient enhanced elastoplasticity. The macrolevel softening is governed by… More >

Kai Long^1,*, Xiaoyu Yang¹, Nouman Saeed¹, Zhuo Chen¹, Yi Min Xie²

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.1, pp. 293-310, 2021, DOI:10.32604/cmes.2021.012734

Abstract A methodology for achieving the maximum bulk or shear modulus in an elastic composite composed of two isotropic phases with distinct Poisson’s ratios is proposed. A topology optimization algorithm is developed which is capable of nding microstructures with extreme properties very close to theoretical upper bounds. The effective mechanical properties of the designed composite are determined by a numerical homogenization technique. The sensitivities with respect to design variables are derived by simultaneously interpolating Young’s modulus and Poisson’s ratio using different parameters. The so-called solid isotropic material with penalization method is developed to establish the optimization formulation. Maximum bulk or shear… More >

Dimitra Papagianni^{1, 2}, Magd Abdel Wahab^{3, 4, *}

CMC-Computers, Materials & Continua, Vol.62, No.1, pp. 79-97, 2020, DOI:10.32604/cmc.2020.07988

Abstract This paper deals with modeling of the phenomenon of fretting fatigue in heterogeneous materials using the multi-scale computational homogenization technique and finite element analysis (FEA). The heterogeneous material for the specimens consists of a single hole model (25% void/cell, 16% void/cell and 10% void/cell) and a four-hole model (25% void/cell). Using a representative volume element (RVE), we try to produce the equivalent homogenized properties and work on a homogeneous specimen for the study of fretting fatigue. Next, the fretting fatigue contact problem is performed for 3 new cases of models that consist of a homogeneous and a heterogeneous part (single… More >

G. Milani¹, T. Rotunno², E. Sacco³, A. Tralli^1,4

Structural Durability & Health Monitoring, Vol.2, No.1, pp. 29-50, 2006, DOI:10.3970/sdhm.2006.002.029

Abstract Aim of the present work is the evaluation of the ultimate load bearing capacity of masonry panels reinforced with FRP strips. The investigation is developed performing both experimental and numerical studies. In particular, several panels subjected to different loading conditions are tested in the Tests Laboratory of the University of Florence (Italy). Then, numerical models based on combined homogenization and limit analysis techniques are proposed. The results obtained by numerical simulations are compared with experimental data. The good agreement obtained shows that the proposed numerical model can be applied for the evaluation of the ultimate load bearing capacity of reinforced… More >