Yanhui Zhang¹, Lianhua Ma¹, Hailiang Su^1,2,3,*, Jirong Qin², Zhining Chen², Kaibiao Deng¹

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 1961-1980, 2024, DOI:10.32604/cmes.2023.045570

Abstract In this paper, to present a lightweight-developed front underrun protection device (FUPD) for heavy-duty trucks, plain weave carbon fiber reinforced plastic (CFRP) is used instead of the original high-strength steel. First, the mechanical and structural properties of plain carbon fiber composite anti-collision beams are comparatively analyzed from a multi-scale perspective. For studying the design capability of carbon fiber composite materials, we investigate the effects of TC-33 carbon fiber diameter (D), fiber yarn width (W) and height (H), and fiber yarn density (N) on the front underrun protective beam of carbon fiber composite materials. Based on the investigation, a material-structure matching… More >

Ye Lu¹, Hengyang Li¹, Sourav Saha², Satyajit Mojumder², Abdullah Al Amin¹, Derick Suarez¹, Yingjian Liu³, Dong Qian³, Wing Kam Liu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.3, pp. 1351-1371, 2021, DOI:10.32604/cmes.2021.017719

Abstract This paper presents the concept of reduced order machine learning finite element (FE) method. In particular, we propose an example of such method, the proper generalized decomposition (PGD) reduced hierarchical deeplearning neural networks (HiDeNN), called HiDeNN-PGD. We described first the HiDeNN interface seamlessly with the current commercial and open source FE codes. The proposed reduced order method can reduce significantly the degrees of freedom for machine learning and physics based modeling and is able to deal with high dimensional problems. This method is found more accurate than conventional finite element methods with a small portion of degrees of freedom. Different… More >

Yan Wang¹, Weina Li¹, Jorg Weissmoller^2,3, Huiling Duan¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.4, pp. 117-118, 2011, DOI:10.3970/icces.2011.018.117

Abstract Surface stress plays a very important role in surface morphology evolution [1-3]. Since the bonding configurations of the atoms at surfaces become different when adsorbates are situated on the surfaces, surface stress can be altered by the presence of adsorbates. Moreover, unless experiments are carried out on high quality single crystals, the surface will typically exhibit corrugation or roughness even when it is nominally planar. We have analyzed this kind of problem and pointed out that stress can be quite significantly affected by surface roughness when the microstructure scale reaches the nanometer range [4].

Therefore, we first build a… More >

Zhou Zhao¹, Boyan Mao², Youjun Liu², Haisheng Yang², Yu Chen^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.116, No.2, pp. 229-245, 2018, DOI: 10.31614/cmes.2018.04192

Abstract In coronary artery bypass grafting (CABG), graft’s poor instant patency may lead to an abnormal hemodynamic environment in anastomosis, which could further cause graft failure after the surgery. This paper investigates the graft hemodynamics with different instant patency, and explores its effect on graft postoperative efficiency. Six CABG 0D/3D coupling multi-scale models which used left internal mammary artery (LIMA) and saphenous vein (SVG) as grafts were constructed. Different types of grafts were examined in the models, including normal grafts, grafts with competitive flow and grafts with anastomotic stenosis. Simulation results indicated that comparing with SVG grafts, there was a greater… More >

S. Liu¹, X. Liu², X. F. Guan³, P.F. He¹, Y. Yuan²

CMES-Computer Modeling in Engineering & Sciences, Vol.92, No.2, pp. 173-191, 2013, DOI:10.3970/cmes.2013.092.173

Abstract Early performance of mass concrete structures is very sensitive to the thermal expansion characteristics of concrete. As a kind of multi-phase composite, concrete has different material composition and microscopic configuration in different scales. Its thermal expansion coefficient (CTE) depends not only on the physical and mechanical properties of the constituents, but also on their distribution. What’s more, CTE is also time-dependent with the procedure of hydration. This research proposes a stochastic multi-scale model for analyzing CTE of concrete. In the developed model, concrete macro-scale is divided into three different levels: cement paste scale, mortar scale and concrete meso-scale; a specific… More >

T. Hasebe¹

CMES-Computer Modeling in Engineering & Sciences, Vol.11, No.3, pp. 145-156, 2006, DOI:10.3970/cmes.2006.011.145

Abstract This paper presents recent achievements in field theoretical approach toward substantial linkage among key hieratical scales dominating polycrystalline plasticity of metals and alloys. Major ingredients of the theory are briefly shown first, which is followed by several overwhelming results and some implications including key factors for dislocation cell structure evolution, key features of polycrystalline plasticity and their rational modeling in crystal plasticity-based constitutive equation. More >

E.A. de Souza Neto¹, S. Amstutz², S.M. Giusti³, A.A. Novotny³

CMES-Computer Modeling in Engineering & Sciences, Vol.62, No.1, pp. 23-56, 2010, DOI:10.3970/cmes.2010.062.023

Abstract A recently proposed algorithm for micro-structural optimization, based on the concept of topological derivative and a level-set domain representation, is applied to the synthesis of elastic and heat conducting bi-material micro-structures. The macroscopic properties are estimated by means of a family of multi-scale constitutive theories where the macroscopic strain and stress tensors (temperature gradient and heat flux vector in the heat conducting case) are defined as volume averages of their microscopic counterparts over a Representative Volume Element (RVE). Several finite element-based examples of micro-structural optimization are presented. Three multi-scale models, providing an upper and a lower bound for the macroscopic… More >

H.K. Mebatsion^1,2, P. Verboven¹, P. T. Jancsók¹, Q.T. Ho¹, B.E. Verlinden³, B.M. Nicolaï^1,3

CMES-Computer Modeling in Engineering & Sciences, Vol.29, No.3, pp. 137-150, 2008, DOI:10.3970/cmes.2008.029.137

Abstract Transport processes of gas and moisture are among the most important physiological processes in plant tissue. Microscale transport models based on Navier-Stokes equations provide insight into such processes at the microscopic scale. Due to microscopic complexity, numerical solutions based on the finite element or finite volume methods are mandatory. Therefore, a 3D geometric model of the tissue is essential. In this article, a novel algorithm for geometric reconstruction of 2D slices of synchrotron tomographic images is presented. The boundaries of 2D cells on individual slices were digitized to establish a set of boundary coordinates and the slice index of individual… More >

S. Liu¹, X. Liu^2,3, Y. Yuan², P. F. He¹, H. A. Mang^2,4

CMC-Computers, Materials & Continua, Vol.39, No.2, pp. 85-112, 2014, DOI:10.3970/cmc.2014.039.085

Abstract Autogenous shrinkage is defined as the bulk deformation of a closed, isothermal, cement-based material system, which is not subjected to external forces. It is associated with the hydration process of the cement paste. From the viewpoint of engineering practice, autogenous shrinkage deformations result in an increase of tensile stresses, which may lead to cracking of early-age concrete. Since concrete is a multi-phase composite with different material compositions and microscopic configurations at different scales, autogenous shrinkage does not only depend on the hydration of the cement paste, but also on the mechanical properties of the constituents and of their distribution. In… More >

G. Haasemann¹, M. Kästner¹ and V. Ulbricht¹

CMC-Computers, Materials & Continua, Vol.3, No.3, pp. 131-146, 2006, DOI:10.3970/cmc.2006.003.131

Abstract Novel textile reinforced composites provide an extremely high adaptability and allow for the development of materials whose features can be adjusted precisely to certain applications. A successful structural and material design process requires an integrated simulation of the material behavior, the estimation of the effective properties which need to be assigned to the macroscopic model and the resulting features of the component. In this context two efficient modelling strategies - the Binary Model (Carter, Cox, and Fleck (1994)) and the Extended Finite Element Method (X-FEM) (Moës, Cloirec, Cartraud, and Remacle (2003)) - are used to model materials which exhibit a… More >