Weigang Jin¹, Lei Chen^2,*, Yifei Li², Shencong Zheng², Yuqi Jiang², Hongkun Chen²

Energy Engineering, Vol.120, No.11, pp. 2469-2487, 2023, DOI:10.32604/ee.2023.043021

Abstract Along with the increasing integration of renewable energy generation in AC-DC power networks, investigating the dynamic behaviors of this complex system with a proper equivalent model is significant. This paper presents an equivalent modeling method for the AC-DC power networks with doubly-fed induction generator (DFIG) based wind farms to decrease the simulation scale and computational burden. For the AC-DC power networks, the equivalent modeling strategy in accordance with the physical structure simplification is stated. Regarding the DFIG-based wind farms, the equivalent modeling based on the sequential identification of multi-machine parameters using the improved chaotic cuckoo search algorithm (ICCSA) is conducted.… More >

Junpeng Lyu¹, Hai Mei^1,2, Liping Zu¹, Lisheng Liu^1,2,*, Liangliang Chu^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.138, No.1, pp. 391-410, 2024, DOI:10.32604/cmes.2023.030614

Abstract This article proposes a modeling method for C/C-ZrC composite materials. According to the superposition of Gaussian random field, the original gray model is obtained, and the threshold segmentation method is used to generate the C-ZrC inclusion model. Finally, the fiber structure is added to construct the microstructure of the three-phase plain weave composite. The reconstructed inclusions can meet the randomness of the shape and have a uniform distribution. Using an algorithm based on asymptotic homogenization and finite element method, the equivalent thermal conductivity prediction of the microstructure finite element model was carried out, and the influence of component volume fraction… More >

Shuai Zhang, Liguo Weng^*

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.3, pp. 2635-2654, 2023, DOI:10.32604/cmes.2023.025405

Abstract Transmission line (TL) Parameter Identification (PI) method plays an essential role in the transmission system. The existing PI methods usually have two limitations: (1) These methods only model for single TL, and can not consider the topology connection of multiple branches for simultaneous identification. (2) Transient bad data is ignored by methods, and the random selection of terminal section data may cause the distortion of PI and have serious consequences. Therefore, a multi-task PI model considering multiple TLs’ spatial constraints and massive electrical section data is proposed in this paper. The Graph Attention Network module is used to draw a… More > Graphic Abstract

Ruijun Liu¹, Haisheng Li^1,*, Zhihan Lv²

CMES-Computer Modeling in Engineering & Sciences, Vol.136, No.2, pp. 985-1022, 2023, DOI:10.32604/cmes.2023.023154

Abstract To understand the current application and development of 3D modeling in Digital Twins (DTs), abundant literatures on DTs and 3D modeling are investigated by means of literature review. The transition process from 3D modeling to DTs modeling is analyzed, as well as the current application of DTs modeling in various industries. The application of 3D DTs modeling in the fields of smart manufacturing, smart ecology, smart transportation, and smart buildings in smart cities is analyzed in detail, and the current limitations are summarized. It is found that the 3D modeling technology in DTs has broad prospects for development and has… More >

Ying He, Yongshuang Wen^*, Xuemei Huang, Leian Zhang, Rujun Song, Chang Li

Energy Engineering, Vol.120, No.2, pp. 445-459, 2023, DOI:10.32604/ee.2022.022223

Abstract In order to study the mechanical properties of the heterogeneous core plate of the wind turbine blade, a modeling method of the core plate based on displacement field variables is proposed. Firstly, the wind turbine blade core plate was modeled according to the theory of modeling heterogeneous material characteristics. Secondly, the three-point bending finite element model of the wind turbine blade core plate was solved by the display dynamic equation to obtain the deformation pattern and force-deformation relationship of the core plate. Finally, the three-point bending static test was conducted to compare with the finite element analysis. The test results… More >

Bowei Wang¹, Wenzhong Tang¹, Lukai Song^2,3,*, Guangchen Bai³

CMES-Computer Modeling in Engineering & Sciences, Vol.133, No.1, pp. 171-193, 2022, DOI:10.32604/cmes.2022.021123

Abstract With increasing design demands of turbomachinery, stochastic flutter behavior has become more prominent and even appears a hazard to reliability and safety. Stochastic flutter assessment is an effective measure to quantify the failure risk and improve aeroelastic stability. However, for complex turbomachinery with multiple dynamic influencing factors (i.e., aeroengine compressor with time-variant loads), the stochastic flutter assessment is hard to be achieved effectively, since large deviations and inefficient computing will be incurred no matter considering influencing factors at a certain instant or the whole time domain. To improve the assessing efficiency and accuracy of stochastic flutter behavior, a dynamic meta-modeling… More >

Bo Zhang^1,2, Keqing Li^1,2, Siqi Zhang^1,2, Yafei Hu^1,2, Bin Han^1,2,*

Journal of Renewable Materials, Vol.10, No.12, pp. 3539-3558, 2022, DOI:10.32604/jrm.2022.021845

Abstract Cemented paste backfill (CPB) is a sustainable mining technology that is widely used in mines and helps to improve the mine environment. To investigate the relationship between aggregate grading and different affecting factors and the uniaxial compressive strength (UCS) of the cemented paste backfill (CPB), Talbol gradation theory and neural networks is used to evaluate aggregate gradation to determine the optimum aggregate ratio. The mixed aggregate ratio with the least amount of cement (waste stone content river sand content = 7:3) is obtained by using Talbol grading theory and pile compactness function and combined with experiments. In addition, the response… More > Graphic Abstract

Xiang Rao^1,2,*, Yina Liu^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.131, No.3, pp. 1403-1429, 2022, DOI:10.32604/cmes.2022.018879

Abstract Projection-based embedded discrete fracture model (pEDFM) is an effective numerical model to handle the flow in fractured reservoirs, with high efficiency and strong generalization of flow models. However, this paper points out that pEDFM fails to handle flow barriers in most cases, and identifies the physical projection configuration of fractures is a key step in pEDFM. This paper presents and proves the equivalence theorem, which explains the geometric nature of physical projection configurations of fractures, that is, the projection configuration of a fracture being physical is equivalent to it being topologically homeomorphic to the fracture, by analyzing the essence of… More >

Hongqiao Wang^1,*, Yanning Cai²

CMES-Computer Modeling in Engineering & Sciences, Vol.130, No.1, pp. 187-203, 2022, DOI:10.32604/cmes.2022.018000

Abstract Inertial system platforms are a kind of important precision devices, which have the characteristics of difficult acquisition for state data and small sample scale. Focusing on the model optimization for data-driven fault state prediction and quantitative degree measurement, a fast small-sample supersphere one-class SVM modeling method using support vectors pre-selection is systematically studied in this paper. By theorem-proving the irrelevance between the model's learning result and the non-support vectors (NSVs), the distribution characters of the support vectors are analyzed. On this basis, a modeling method with selected samples having specific geometry character from the training sets is also proposed. The… More >

Lijian Xu¹, Tianyang Yang², Lekang Yin³, Ye Kong², Yuri Vassilevski^4,5, Fuyou Liang^1,5,6,*

CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.2, pp. 509-526, 2020, DOI:10.32604/cmes.2020.010719

Abstract Computational modeling methods have been increasingly employed to quantify aortic hemodynamic parameters that are challenging to in vivo measurements but important for the diagnosis/treatment of aortic disease. Although the presence of turbulence-like behaviors of blood flow in normal or diseased aorta has long been confirmed, the majority of existing computational model studies adopted the laminar flow assumption (LFA) in the treatment of sub-grid flow variables. So far, it remains unclear whether LFA would significantly compromise the reliability of hemodynamic simulation. In the present study, we addressed the issue in the context of a specific aortopathy, namely aortic dilation, which is… More >