Taeshik Yoon^1,†, Sumin Kang^1,†, Tae Yeob Kang¹, Taek-Soo Kim^1,2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 351-361, 2019, DOI:10.32604/cmes.2019.06672

Abstract Detection of cracks is a great concern in production and operation processes of graphene based devices to ensure uniform quality. Here, we show a detection method for graphene cracks by electromagnetic induction. The time varying magnetic field leads to induced voltage signals on graphene, and the signals are detected by a voltmeter. The measured level of induced voltage is correlated with the number of cracks in graphene positively. The correlation is attributed to the increasing inductive characteristic of defective graphene, and it is verified by electromagnetic simulation and radio frequency analysis. Furthermore, we demonstrate that More >

Ying Wang^1,*, Yuqian Zheng¹

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 375-419, 2019, DOI:10.32604/cmes.2019.06905

Abstract A numerical simulation method for the damage evolution of high-strength steel wire in a bridge cable under the action of pre-corrosion and fatigue is presented in this paper. Based on pitting accelerated crack nucleation theory in combination with continuum mechanics, cellular automata technology (CA) and finite element (FE) analysis, the damage evolution process of steel wire under pre-corrosion and fatigue is simulated. This method automatically generates a high-strength steel wire model with initial random pitting defects, and on the basis of this model, the fatigue damage evolution process is simulated; thus, the fatigue life and… More >

Ali Raza¹, Muhammad Shoaib Arif^1,*, Muhammad Rafiq², Mairaj Bibi³, Muhammad Naveed¹, Muhammad Usman Iqbal⁴, Zubair Butt⁴, Hafiza Anum Naseem⁴, Javeria Nawaz Abbasi³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 445-465, 2019, DOI:10.32604/cmes.2019.06454

Abstract This writing is an attempt to explain a reliable numerical treatment for stochastic computer virus model. We are comparing the solutions of stochastic and deterministic computer virus models. This paper reveals that a stochastic computer virus paradigm is pragmatic in contrast to the deterministic computer virus model. Outcomes of threshold number C^∗ hold in stochastic computer virus model. If C^∗ < 1 then in such a condition virus controlled in the computer population while C^∗ > 1 shows virus persists in the computer population. Unfortunately, stochastic numerical methods fail to cope with large step sizes of time. More >

Mustafa Turkyilmazoglu^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 63-81, 2019, DOI:10.32604/cmes.2019.06858

Abstract A ratio approach based on the simple ratio test associated with the terms of homotopy series was proposed by the author in the previous publications. It was shown in the latter through various comparative physical models that the ratio approach of identifying the range of the convergence control parameter and also an optimal value for it in the homotopy analysis method is a promising alternative to the classically used h-level curves or to the minimizing the residual (squared) error. A mathematical analysis is targeted here to prove the equivalence of both the ratio approach and the More >

Yana Wang^1,2,3,4, Ruodi Jia^1,5, Fengrui Liu^1,5,6,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 215-234, 2019, DOI:10.32604/cmes.2019.06542

Abstract Delamination and matrix cracking are two common failure mechanisms in composite structures, and are usually coupled with each other, leading to multiple failures pattern. This paper proposed a fast damage prediction methodology for composite laminated structures based on the ply-by-ply 2D (two dimensional) FE model of composite laminates in the transverse plane. The layer-wise 2D FE model was firstly used in conjunction with the integrated XFEM/CE strategy, which simulated the interface delamination with cohesive elements and the intra-ply matrix crack with XFEM (extended finite element method). To realize ply-by-ply 2D FE (finite element) modeling of More >

Izyan Syazana Awaludin^{1, 2}, Anuar Ishak^2,*, Ioan Pop³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 203-214, 2019, DOI:10.32604/cmes.2019.06594

Abstract The present study considers the magnetohydrodynamic (MHD) stagnation point flow with chemical reaction effect over a permeable stretching/shrinking sheet. The partial differential equations are reduced to a set of ordinary differential equations using a similarity transformation. The transformed equations are then solved numerically by employing the bvp4c function available in the MATLAB software. The numerical results illustrate the effects of several parameters on the skin friction coefficient, local Nusselt number and the local Sherwood number. Dual solutions are obtained for a certain range of parameters. The temporal stability analysis is carried out to determine which More >

Yang Liu^1,*, Yue Qiao², Tiange Li³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 177-201, 2019, DOI:10.32604/cmes.2019.06338

Abstract This paper studies the effect of ice resistance on the icebreaking capacity and speed of an icebreaking vessel. We combine an improved Correct Smoothed Particle Method (CSPM) with a material low-speed collision fracture model to numerically simulate the continuous icebreaking and rolling process of crushed. Using this model, we investigate the icebreaking resistance and immersion resistance during the icebreaking process, taking into account the fluid (water) as the elastic boundary support and the fluid-solid coupling interaction. We compare the icebreaking resistance and broken ice fracture shapes obtained by the numerical calculation with the theoretical analytical More >

Zhe Li¹, Fan Yang^1,*, Yaping Liu¹, Yukui Gao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 157-175, 2019, DOI:10.32604/cmes.2019.05187

Abstract In this paper, we investigated the shot blast treatment for derusting application through finite element (FE) simulations with a large number of random shots. The element deletion technique based on dynamic failure criteria was used to model the removal of rust. The cohesive surface model with damage evolution was used to characterize the decohesion of the rust/substrate interface. The effects of various processing and material parameters on the derusting effectiveness were examined. The results show that the rate of derusting mainly depends on the shot size, velocity and impinging angle, with little relevance to the More >

Filip Putar¹, Jurica Sorić^1,*, Tomislav Lesičar¹, Zdenko Tonković¹

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 123-156, 2019, DOI:10.32604/cmes.2019.06562

Abstract A novel multiscale algorithm based on the higher-order continuum at both micro- and macrostructural level is proposed for the consideration of the quasi-brittle damage response of heterogeneous materials. Herein, the microlevel damage is modelled by the degradation of the homogenized stress and tangent stiffness tensors, which are then upscaled to govern the localization at the macrolevel. The C¹ continuity finite element employing a modified case of Mindlin’s form II strain energy density is derived for the softening analysis. To the authors’ knowledge, the finite element discretization based on the strain gradient theory is applied for the… More >

Junjun Jiang¹, Congqing Wang^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.1, pp. 105-121, 2019, DOI:10.32604/cmes.2019.06277

Abstract Aircraft skin health concerns whether the aircraft can fly safely. In this paper, an improved mechanical structure of the aircraft skin inspection robot was introduced. Considering that the aircraft skin surface is a curved environment, we assume that the curved environment is equivalent to an inclined plane with a change in inclination. Based on this assumption, the Cartesian dynamics model of the robot is established using the Lagrange method. In order to control the robot’s movement position accurately, a position backstepping control scheme for the aircraft skin inspection robot was presented. According to the dynamic More >