Kai Long¹, Ayesha Saeed¹, Jinhua Zhang², Yara Diaeldin¹, Feiyu Lu¹, Tao Tao³, Yuhua Li^1,*, Pengwen Sun⁴, Jinshun Yan⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.1, pp. 43-67, 2024, DOI:10.32604/cmes.2023.031538

Abstract This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum structures. These structures, commonly encountered in engineering applications, often involve complex objective and constraint functions that cannot be readily expressed as explicit functions of the design variables. As a result, sequential approximation techniques have emerged as the preferred strategy for addressing a wide array of topology optimization challenges. Over the past several decades, topology optimization methods have been advanced remarkably and successfully applied to solve engineering problems incorporating diverse physical backgrounds. In comparison to the large-scale equation solution,… More >

Yongbin Zhang^*

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-7, 2017, DOI:10.5098/hmt.8.19

Abstract This paper reviews the models for the fluid flow in micro/nano channels developed previously. These models include the full MDS (molecular dynamics simulation) model, the quasi-continuum model, the modified Navier-Stokes equation model, the dissipative particle dynamics method, the lattice Boltzman method, the multiscale hybrid model and the flow factor approach model. It was pointed out that most of the models have their own imperfections like huge time and computer storage consumption for simulating a system of realistic size or inaccuracy because of the model limitation. It was also mentioned that the most challenging is to develop efficient models for simulating… More >

Jian Li^1,2, Yongbin Zhang^1,*

Frontiers in Heat and Mass Transfer, Vol.16, pp. 1-5, 2021, DOI:10.5098/hmt.16.21

Abstract The paper introduces the flow equations for the fluid flows in a cylindrical tube respectively on the macroscale, multiscale and nanoscale, especially recently developed ones. It manifests that when these equations should be used in calculating the transferred mass and what should be taken into consideration when the tube inner radius is reduced to very small values. It gives an important indication on how to treat the mass transfer calculation for the tube flow on different size scales. More >

Jiazheng Du^*, Xue Cong, Ying Zhang

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 1091-1120, 2023, DOI:10.32604/cmes.2023.025585

Abstract Spacecraft in the aerospace field and military equipment in the military field are at risk of being impacted by external objects, which can cause local damage to the structure. The randomness of local damage is a new challenge for structural design, and it is essential to take random damage into account in the conceptual design phase for the purpose of improving structure’s resistance to external shocks. In this article, a random damaged structure is assumed to have damages of the same size and shape at random locations, and the random damage is considered as multiple damage conditions of the structure.… More > Graphic Abstract

Runze Song¹, Fei Han^1,*, Yong Mei^2,*, Yunhou Sun², Ao Zhang²

CMES-Computer Modeling in Engineering & Sciences, Vol.133, No.2, pp. 389-412, 2022, DOI:10.32604/cmes.2022.021127

Abstract This paper proposes a hybrid peridynamic and classical continuum mechanical model for the high-temperature damage and fracture analysis of concrete structures. In this model, we introduce the thermal expansion into peridynamics and then couple it with the thermoelasticity based on the Morphing method. In addition, a thermomechanical constitutive model of peridynamic bond is presented inspired by the classic Mazars model for the quasi-brittle damage evolution of concrete structures under high-temperature conditions. The validity and effectiveness of the proposed model are verified through two-dimensional numerical examples, in which the influence of temperature on the damage behavior of concrete structures is investigated.… More >

Li Lei¹, Zihao Wang^2,*, Yong Wu³

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.3, pp. 1815-1830, 2022, DOI:10.32604/cmes.2022.019855

Abstract It is essential to fully understand master the traffic characteristics of the self-stabilizing control effect and road characteristics to ensure the regular operation of transportation. Traffic flow on curved roads and slopes is irregular and more complicated than that on the straight road. However, most of the research only considers the effect of self-stabilizing in the straight road. This study attempts to bridge this deficiency from the following three aspects. First, we review the potential influencing factors of traffic flow stability, which are related to the vehicle's steady velocity, history velocity, and the turn radius of the road and the… More >

Harrison Schurr, Andrei Tuluca^*, Beth Bailey

International Journal of Mental Health Promotion, Vol.24, No.2, pp. 159-167, 2022, DOI:10.32604/ijmhp.2022.017990

Abstract Suicide is a top ten cause of mortality in the United States. In previous literature the suicide rates in rural communities have been reported to be greater than those of more urban communities. Additionally, these studies have discussed many potential causes for the unfortunate disparity in rates. One cause often discussed is lack of mental health care providers in rural communities. The data for this study was gathered from the CDC’s WONDER database and the NPPES NPI Registry. The urban-rural categorization of counties used the 2013 NCHS Urban-Rural Scheme. Statistical analysis included chi-square tests, paired t-tests, and stepwise regression analyses.… More >

Jiazheng Du^*, Ying Zhang, Fanwei Meng

CMES-Computer Modeling in Engineering & Sciences, Vol.129, No.2, pp. 661-687, 2021, DOI:10.32604/cmes.2021.017580

Abstract Traditional topology optimization methods may lead to a great reduction in the redundancy of the optimized structure due to unexpected material removal at the critical components. The local failure in critical components can instantly cause the overall failure in the structure. More and more scholars have taken the fail-safe design into consideration when conducting topology optimization. A lot of good designs have been obtained in their research, though limited regarding minimizing structural compliance (maximizing stiffness) with given amount of material. In terms of practical engineering applications considering fail-safe design, it is more meaningful to seek for the lightweight structure with… More >

M. N. Tarhuni^*, W. R. Sulaiman, M. Z. Jaafar, M. Milad, A. M. Alghol

Energy Engineering, Vol.118, No.4, pp. 761-795, 2021, DOI:10.32604/EE.2021.016645

Abstract Fluid flow in fractured media has been studied for decades and received considerable attention in the oil and gas industry because of the high productivity of naturally fractured reservoirs. Due to formation complexity and reservoir heterogeneity, characterizing fluid flow with an appropriate reservoir model presents a challenging task that differs relatively from homogeneous conventional reservoirs in many aspects of view, including geological, petrophysical, production, and economics. In most fractured reservoirs, fracture networks create complex pathways that affect hydrocarbon flow, well performance, hence reservoir characterization. A better and comprehensive understanding of the available reservoir modeling approaches is much needed to accurately… More >

Jurica Sorić^*, Boris Jalušić, Tomislav Lesičar, Filip Putar, Zdenko Tonković

The International Conference on Computational & Experimental Engineering and Sciences, Vol.23, No.1, pp. 1-1, 2021, DOI:10.32604/icces.2021.08043

Abstract In modeling of material deformation responses, the physical phenomena such as stress singularity problems, strain localization and modeling of size effects cannot be properly captured by means of classical continuum mechanics. Therefore, various regularization techniques have been developed to overcome these problems. In the case of gradient approach the implicit gradient formulations are usually used when dealing with softening. Although the structural responses are mesh objective, they suffer from spurious damage growth. Therefore, a new formulation based on the strain gradient continuum theory, which includes both strain gradients and their stress conjugates, has been proposed. In this way, a physically… More >