Shichao Cao^*, Yonggang Dong, Xiaoying Liu

Energy Engineering, Vol.121, No.4, pp. 1109-1125, 2024, DOI:10.32604/ee.2023.043004

Abstract The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine. It also has the same inertia, damping, frequency, voltage regulation, and other external performance as the generator. It is the key technology to realize new energy grid connections’ stable and reliable operation. This project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor. A new energy storage method is proposed. The mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power, state of charge,… More >

Xinzong Wang¹, Xiaofang Kang^1,2,*, Qingguan Lei¹

CMES-Computer Modeling in Engineering & Sciences, Vol.137, No.2, pp. 1749-1771, 2023, DOI:10.32604/cmes.2023.027745

Abstract The chaotic motion behavior of the rectangular conductive thin plate that is simply supported on four sides by airflow and mechanical external excitation in a magnetic field is studied. According to Kirchhoff ’s thin plate theory, considering geometric nonlinearity and using the principle of virtual work, the nonlinear motion partial differential equation of the rectangular conductive thin plate is deduced. Using the separate variable method and Galerkin’s method, the system motion partial differential equation is converted into the general equation of the Duffing equation; the Hamilton system is introduced, and the Melnikov function is used to analyze the Hamilton system,… More > Graphic Abstract

Zubing Tang^*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.8, pp. 2161-2170, 2023, DOI:10.32604/fdmp.2023.026608

Abstract The mechanical behavior of the test string in deep wells is generally relatively complex as a result of the high temperature and high pressure, severe dogleg and buckling effects, which in some circumstances can even lead to string failure. Traditional computational methods for the analysis of these behaviors are often inaccurate. For this reason, here a more accurate mechanical model of the test string is introduced by considering variables such as temperature, pressure, wellbore trajectory, and buckling, as well as combining them with the deformation and string constraint conditions brought in by changes in temperature and pressure during the tripping,… More >

Shidong Nie^1,2,*, Song Ran^1,2, Di Wu^1,2,3, Jieyu Chen^1,2, Hui Wang^1,2, Qike Wei⁴

Journal of Renewable Materials, Vol.10, No.2, pp. 487-510, 2022, DOI:10.32604/jrm.2022.017275

Abstract The Moso bamboo, a renewable green building material used in various new green buildings, have received extensive attention with the promotion of the concept of green buildings. To explore the mechanical properties of Moso bamboo connections with external clamp steel plates, the 16 specimens were designed by changing the bolt diameters and the end distances of the bolt holes. Their static tension tests were conducted to investigate bearing capacities and failure modes of different connection configurations. Based on test results, three failure modes of these connections were obtained, including the shear failure of bolt shank, bearing failure of bolt hole… More > Graphic Abstract

Zhimin Zhang, Tianhe Kang^*

CMC-Computers, Materials & Continua, Vol.66, No.1, pp. 341-357, 2021, DOI:10.32604/cmc.2020.012104

Abstract In view of the three-dimensional dynamic abutment pressure, the influence of the far-field hard stratum (FHS) in deep, thick coal seams is indeterminant. Based on elastic foundation theory, a three-dimensional dynamic prediction model of the abutment pressure was established. Using this model, the dynamic change in the coal seam abutment pressure caused by the movement of the FHS was studied, and a method for determining the dynamic change range of the abutment pressure was developed. The results of the new prediction model of the abutment pressure are slightly higher than the measured values, with an error of 0.51%, which avoids… More >

Dan Ma^{1, 2}, Hongyu Duan², Qi Zhang^{3, *}, Jixiong Zhang¹, Wenxuan Li², Zilong Zhou², Weitao Liu⁴

CMC-Computers, Materials & Continua, Vol.65, No.3, pp. 2123-2141, 2020, DOI:10.32604/cmc.2020.011430

Abstract Gas fracturing, which overcomes the limitation of hydraulic fracturing, is a potential alternative technology for the development of unconventional gas and oil resources. However, the mechanical principle of gas fracturing has not been learned comprehensively when the fluid is injected into the borehole. In this paper, a damagebased model of coupled thermal-flowing-mechanical effects was adopted to illustrate the mechanical principle of gas fracturing. Numerical simulation tools Comsol Multiphysics and Matlab were integrated to simulate the coupled process during the gas fracturing. Besides, the damage evolution of drilling areas under several conditions was fully analyzed. Simulation results indicate that the maximum… More >

Arka Das¹, Anthony Khoury¹, Eduardo Divo^{1, *}, Victor Huayamave¹, Andres Ceballos², Ron Eaglin², Alain Kassab³, Adam Payne⁴, Vijay Yelundur⁴, Hubert Seigneur⁵

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.3, pp. 757-777, 2020, DOI:10.32604/cmes.2020.08164

Abstract This paper presents a numerical reduced order model framework to simulate the physics of the thermomechanical processes that occur during c-Si photovoltaic (PV) cell fabrication. A response surface based on a radial basis function (RBF) interpolation network trained by a Proper Orthogonal Decomposition (POD) of the solution fields is developed for fast and accurate approximations of thermal loading conditions on PV cells during the fabrication processes. The outcome is a stand-alone computational tool that provides, in real time, the quantitative and qualitative thermomechanical response as a function of user-controlled input parameters for fabrication processes with the precision of 3D finite… More >

Nian Li^*

Structural Durability & Health Monitoring, Vol.13, No.4, pp. 331-346, 2019, DOI:10.32604/sdhm.2019.07521

Abstract The investigation focusing on the mechanical behaviors at the microstructural level in composite materials can provide valuable insight into the failure mechanisms at larger scales. A micromechanics damage model which comprises the coupling of the matrix constitutive model and the cohesive zone (CZM) model at fiber-matrix interfaces is presented to evaluate the transverse tensile damage behaviors of unidirectional (UD) fiber-reinforced polymer (FRP) composites. For the polymeric matrix that exhibits highly non-linear mechanical responses, special focus is paid on the formulation of the constitutive model, which characterizes a mixture of elasticity, plasticity as well as damage. The proposed constitutive model includes… More >

Leiting Dong^1,2, Satya N. Atluri^1,3

CMC-Computers, Materials & Continua, Vol.33, No.2, pp. 111-154, 2013, DOI:10.3970/cmc.2013.033.111

Abstract In this study, SGBEM Voronoi Cells (SVCs), with each cell representing a grain of the material at the micro-level, are developed for direct micromechanical numerical modeling of heterogeneous composites. Each SVC can consist of either a (each with a different) homogenous isotropic matrix, and can include micro-inhomogeneities such as inclusions, voids of a different material, and cracks. These inclusions and voids in each SVC can be arbitrarily-shaped, such as circular, elliptical, polygonal, etc., for 2D problems. Further, the cracks in each SVC can be fully-embedded, edge, branching, or intersecting types, with arbitrary curved shapes. By rearranging the weakly-singular boundary integral… More >

xuan pei

The International Conference on Computational & Experimental Engineering and Sciences, Vol.18, No.4, pp. 123-124, 2011, DOI:10.3970/icces.2011.018.123

Abstract The constitutive model always plays a fundamental role in biomechanical researches on human trachea soft tissues. Due to the variety of constitutive theories, the selection of the appropriate one and the determination of its material parameters becomes a question. Based on longitudinal and circumferential extension tests on human tracheas, three constitutive models-the isotropic M-R model, the Holzapfel's anisotropic model and modified Hozapfel's model respectively, were utilized in this paper to fit the experimental data. A jointly fitting strategy was also proposed to obtain the anisotropic model parameters. For the isotropic M-R model, material parameters optimized from different directions are significantly… More >