Chengbao Hu^1,2,3, Shilin Gong^4,*, Bin Chen^1,2,3, Zhongling Zong⁴, Xingwang Bao⁵, Xiaojian Ru⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 997-1015, 2024, DOI:10.32604/cmes.2024.048640

Abstract Strain localization frequently occurs in cohesive materials with friction (e.g., composites, soils, rocks) and is widely recognized as a fundamental cause of progressive structural failure. Nonetheless, achieving high-fidelity simulation for this issue, particularly concerning strong discontinuities and tension-compression-shear behaviors within localized zones, remains significantly constrained. In response, this study introduces an integrated algorithm within the finite element framework, merging a coupled cohesive zone model (CZM) with the nonlinear augmented finite element method (N-AFEM). The coupled CZM comprehensively describes tension-compression and compression-shear failure behaviors in cohesive, frictional materials, while the N-AFEM allows nonlinear coupled intra-element discontinuities without necessitating extra nodes or… More >

Tianyi Li^1,2, Xin Gu², Qing Zhang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 339-361, 2024, DOI:10.32604/cmes.2024.047566

Abstract This study proposes a comprehensive, coupled thermomechanical model that replaces local spatial derivatives in classical differential thermomechanical equations with nonlocal integral forms derived from the peridynamic differential operator (PDDO), eliminating the need for calibration procedures. The model employs a multi-rate explicit time integration scheme to handle varying time scales in multi-physics systems. Through simulations conducted on granite and ceramic materials, this model demonstrates its effectiveness. It successfully simulates thermal damage behavior in granite arising from incompatible mineral expansion and accurately calculates thermal crack propagation in ceramic slabs during quenching. To account for material heterogeneity, the model utilizes the Shuffle algorithm… More >

Ying Wang^1,*, Longxiao Chao¹, Jun Chen², Songbai Jiang¹

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 201-227, 2024, DOI:10.32604/cmes.2024.046129

Abstract In order to investigate the fatigue performance of orthotropic anisotropic steel bridge decks, this study realizes the simulation of the welding process through elastic-plastic finite element theory, thermal-structural sequential coupling, and the birth-death element method. The simulated welding residual stresses are introduced into the multiscale finite element model of the bridge as the initial stress. Furthermore, the study explores the impact of residual stress on crack propagation in the fatigue-vulnerable components of the corroded steel box girder. The results indicate that fatigue cracks at the weld toe of the top deck, the weld root of the top deck, and the… More > Graphic Abstract

Mir Abdullatif Yahya¹, Fatma Tunali¹, Dilek Killi^2,*, Atalay Sökmen²

Phyton-International Journal of Experimental Botany, Vol.93, No.3, pp. 427-444, 2024, DOI:10.32604/phyton.2024.046271

Abstract An effective in vitro propagation protocol was designed for Lavandula angustifolia Miller, a medicinal aromatic plant that is a prominent source of volatile organic compounds (VOCs). Murashige and Skoog media were supplemented with various concentrations of Plant Growth Regulators (PGRs), and the growth parameters of the nodal segments were examined. Nodal explants formed callus when they were supplemented with 2 mg/L of 6-Benzylaminopurine (BAP). The superior hormonal concentration of Murashige and Skoog (MS) media for the proliferation of shoots from callus cultures (39.33%) was 5 mg/L of 2-Isopentenyl adenine (2iP), and the favorable media for the growth of L. angustifolia… More >

Xue Liang^1,2, Linjuan Wang^3,*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 2807-2834, 2024, DOI:10.32604/cmes.2024.046770

Abstract The peridynamics (PD), as a promising nonlocal continuum mechanics theory, shines in solving discontinuous problems. Up to now, various numerical methods, such as the peridynamic mesh-free particle method (PD-MPM), peridynamic finite element method (PD-FEM), and peridynamic boundary element method (PD-BEM), have been proposed. PD-BEM, in particular, outperforms other methods by eliminating spurious boundary softening, efficiently handling infinite problems, and ensuring high computational accuracy. However, the existing PD-BEM is constructed exclusively for bond-based peridynamics (BBPD) with fixed Poisson’s ratio, limiting its applicability to crack propagation problems and scenarios involving infinite or semi-infinite problems. In this paper, we address these limitations by… More >

Shijie Lin¹, Zimo Wang¹, Hongbo Zhu², Conghui Wang³, Hongfeng Wang², Dawei Zhang¹, Tianbing Gou¹, Guangdao Bao¹, Ye Luo¹, Huaijiang He¹, Zhonghui Zhang^1,*

Phyton-International Journal of Experimental Botany, Vol.93, No.2, pp. 277-289, 2024, DOI:10.32604/phyton.2024.046989

Abstract Tilia amurensis is an economically valuable broadleaf tree species in Northeast China. The production of high-quality T. amurensis varieties at commercial scales has been greatly limited by the low germination rates. There is thus a pressing need to develop an organogenesis protocol for in vitro propagation of T. amurensis to alleviate a shortage of high-quality T. amurensis seedlings. Here, we established a rapid in vitro propagation system for T. amurensis from mature zygotic embryos and analyzed the effects of plant growth regulators and culture media in different stages. We found that Woody plant medium (WPM) was the optimal primary culture… More >

Zediao Chen, Feng Liu^*

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.2, pp. 2215-2236, 2024, DOI:10.32604/cmes.2023.046618

Abstract Crack propagation in brittle material is not only crucial for structural safety evaluation, but also has a wide-ranging impact on material design, damage assessment, resource extraction, and scientific research. A thorough investigation into the behavior of crack propagation contributes to a better understanding and control of the properties of brittle materials, thereby enhancing the reliability and safety of both materials and structures. As an implicit discrete element method, the Discontinuous Deformation Analysis (DDA) has gained significant attention for its developments and applications in recent years. Among these developments, the particle DDA equipped with the bonded particle model is a powerful… More >

Diguang Gong¹, Junbin Chen¹, Cheng Cheng², Yuanyuan Kou^2,*

Energy Engineering, Vol.121, No.2, pp. 425-437, 2024, DOI:10.32604/ee.2023.030196

Abstract Horizontal well-stimulation is the key to unconventional resource exploration and development. The development mode of the well plant helps increase the stimulated reservoir volume. Nevertheless, fracture interference between wells reduces the fracturing effect. Here, a 2D hydro-mechanical coupling model describing hydraulic fracture (HF) propagation is established with the extended finite element method, and the effects of several factors on HF propagation during multiple wells fracturing are analyzed. The results show that with an increase in elastic modulus, horizontal principal stress difference and injection fluid displacement, the total fracture area and the reservoir stimulation efficiency are both improved in all three… More >

Wenzhi Xu¹, ZhuoJia Fu^1,*, Qiang Xi¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-1, 2023, DOI:10.32604/icces.2023.010437

Abstract Acoustic wave propagation through an inhomogeneous medium may lead to undergo substantial modification. This paper proposed a Green’s functions-based method for the simulation of wave propagation through inhomogeneous medium waveguides. Under ideal conditions, a modified wave equation is derived by variable transformations, in which only the wave speed varies with spatial coordinates. Based on the modified wave equation the acoustic Green’s functions are derived. Then, the localized method of fundamental solution (LMFS) in conjunction with the acoustic Green’s functions is introduced to solve the modified wave equation. In the LMFS, the acoustic Green’s function is considered as its basic function… More >

Yujia Liu^1,2, Bo Xu¹, Sen Tang³, Lang Li¹, Chao He¹, Qingyuan Wang^1,2,3, Chong Wang^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.27, No.4, pp. 1-1, 2023, DOI:10.32604/icces.2023.010057

Abstract This paper presents a thermodynamic characterization method for estimating the internal crack growth rate, which has been a puzzle in very high cycle fatigue research. A theoretical approach of surface temperature is established with crack size, initiation site, and time for thin sheet material. Infrared thermography is used to study the inner crack behavior and the heat dissipation phenomenon under 20 kHz vibration loading on high-strength stainless steel. A numerical simulation reveals the consequent temperature elevation on the surfaces by the heat generation at the crack tip and the heat conduction. Ultimately, the internal crack growth rate and final fatigue… More >