M. Farid Yahya¹, Reduan Mat Dan^2,3,*, M. Fadzlee Samsubaha¹, Zaini Rashid¹, Azma Putra^2,3,*

Sound & Vibration, Vol.57, pp. 119-131, 2023, DOI:10.32604/sv.2023.045029

Abstract A case study of excessive vibration on a motor-compressor system is presented in this paper. After barely two months of operation, the reciprocating compressor motor’s routine monitoring revealed excessive axial vibration amplitude. For this reason, the Operational Modal Analysis (OMA) was carried out in order to identify the primary cause. According to the investigation, one of the harmonic components which was 18 times the motor’s running speed matched with a resonance frequency of 112 Hz. According to OMA study, the motor was vibrating in torsional motion because the compressor’s load had stimulated the entire motor-compressor unit at this resonance frequency.… More >

Youhao Wang¹, Chuntian Zhe¹, Chang Guo², Jinpeng Li³, Jinheng Li³, Shen Cheng², Zitian Wu¹, Suoying He¹, Ming Gao^1,*

FDMP-Fluid Dynamics & Materials Processing, Vol.19, No.12, pp. 2965-2980, 2023, DOI:10.32604/fdmp.2023.029292

Abstract Flow channels with a variable cross-section are important components of piping system and are widely used in various fields of engineering. Using a finite element method and modal analysis theory, flow-induced noise, mode shapes, and structure-borne noise in such systems are investigated in this study. The results demonstrate that the maximum displacement and equivalent stress are located in the part with variable cross-sectional area. The average excitation force on the flow channel wall increases with the flow velocity. The maximum excitation force occurs in the range of 0–20 Hz, and then it decreases gradually in the range of 20–1000 Hz.… More >

Gaoyuan Yu¹, Yunfeng Lou², Hang Dong³, Junjie Li¹, Xianlong Jin^1,*

CMC-Computers, Materials & Continua, Vol.76, No.3, pp. 2795-2816, 2023, DOI:10.32604/cmc.2023.037375

Abstract The strict and high-standard requirements for the safety and stability of major engineering systems make it a tough challenge for large-scale finite element modal analysis. At the same time, realizing the systematic analysis of the entire large structure of these engineering systems is extremely meaningful in practice. This article proposes a multilevel hierarchical parallel algorithm for large-scale finite element modal analysis to reduce the parallel computational efficiency loss when using heterogeneous multicore distributed storage computers in solving large-scale finite element modal analysis. Based on two-level partitioning and four-transformation strategies, the proposed algorithm not only improves the memory access rate through… More >

Amthal Hakim¹, Wael Slika^1,*, Rawan Machmouchi¹, Adel Elkordi²

Structural Durability & Health Monitoring, Vol.17, No.3, pp. 175-194, 2023, DOI:10.32604/sdhm.2022.023027

Abstract Corrosion of reinforcing steel in concrete elements causes minor to major damage in different aspects. It may lead to spalling of concrete cover, reduction of section’s capacity and can alter the dynamic properties. For the dynamic properties, natural frequency is to be a reliable indicator of structural integrity that can be utilized in non-destructive corrosion assessment. Although the correlation between natural frequency and corrosion damage has been reflected in different experimental programs, few attempts have been made to investigate this relationship in forward modeling and/or structural health monitoring techniques. This can be attributed to the limited available data, the complex… More >

Sihua Wang^1,2, Xujie Li^1,2,*

Structural Durability & Health Monitoring, Vol.16, No.4, pp. 361-382, 2022, DOI:10.32604/sdhm.2022.023851

Abstract The portal structure is the support equipment in the catenary, which bears the load of contact suspension and support equipment. In practical work, with the change of external forces, the support equipment bears complex and changeable loads, so it has higher requirements for its reliability and safety. In order to study the dynamic characteristics of catenary portal structure on continuous beam of four-way bridge, taking the catenary portal structure on Dshaping four-way bridge as the research object, the portal structure simulation model of bridge-network integration was established in Midas Civil. The maximum point of deformation and stress was determined by… More >

Meng Zhang¹, Zhichao Zhou¹, Guifeng Zhao^1,*, Fangfang Wang^2,*

CMES-Computer Modeling in Engineering & Sciences, Vol.134, No.1, pp. 673-698, 2023, DOI:10.32604/cmes.2022.021463

Abstract Computational fluid dynamics (CFD) and the finite element method (FEM) are used to investigate the wind-driven dynamic response of cantilever traffic signal support structures as a whole. By building a finite element model with the same scale as the actual structure and performing modal analysis, a preliminary understanding of the dynamic properties of the structure is obtained. Based on the two-way fluid-structure coupling calculation method, the wind vibration response of the structure under different incoming flow conditions is calculated, and the vibration characteristics of the structure are analyzed through the displacement time course data of the structure in the cross-wind… More >

Tareq Al-hababi^1,2, Nizar Faisal Alkayem^1,3, Li Cui⁴, Shixiang Zhang⁵, Cong Liu⁶, Maosen Cao^1,2,*

Structural Durability & Health Monitoring, Vol.16, No.1, pp. 15-35, 2022, DOI:10.32604/sdhm.2022.020418

Abstract A significant amount of research is concerned with dynamic modal parameters for damage detection of structural conditions due to their simplicity in use and feasibility. However, their use for damage detection should be performed with special attention, particularly in operational and environmental conditions subjected to temperature changes. Beams in construction industries experience different loading types, such as temperature changes leading to crack initiation and propagation. Changed physical and dynamic properties such as natural frequencies and mode shapes indicate that damage has occurred within the structures. In this study, vibration analysis of cantilever and cantilever simply supported beams has been carried… More >

Deepak Kumar Singh^*

Sound & Vibration, Vol.55, No.3, pp. 253-262, 2021, DOI:10.32604/sv.2021.011627

Abstract The analysis of spliced column has been carried out to detect optimum location of providing splices in the column. In the present work, static and dynamic (free vibration) analyses of spliced column have been done by randomising the location of splicing. A symmetrical four storey steel framed building has been modelled, analysed and designed for loads (dead, live and earthquake loads) recommended by Indian Codal provisions using Staad.Pro. The critical column at each floor level is identified based on axial force (AF), bending moment (BM) and shear force (SF). The total 16 models of spliced columns have been designed and… More >

Jianqiang Xiong^*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.3, pp. 555-567, 2021, DOI:10.32604/fdmp.2021.015429

Abstract A robust optimization design method is proposed to investigate the influence of the hook position on the vertical vibration (bending) of an automobile exhaust system. A block diagram for the robustness analysis of the exhaust system is initially constructed from the major affecting factors. Secondly, the second-order inertia force is set as the vibration excitation source of the exhaust system and the displacement of four hooks of the exhaust system is selected as the variable factor. Then tests are carried out to investigate the resulting vertical bending considering four influencing factors and three levels of analysis. Finally, a variance analysis… More >

Nguyễn T. Quyền^1,*, N. Dourado², A. J. P. Gomes^3,4, F. B. N. Ferreira¹

CMC-Computers, Materials & Continua, Vol.67, No.3, pp. 2765-2795, 2021, DOI:10.32604/cmc.2021.013164

Abstract The combination of a 4-node quadrilateral mixed interpolation of tensorial components element (MITC4) and the cell-based smoothed finite element method (CSFEM) was formulated and implemented in this work for the analysis of free vibration and unidirectional buckling of shell structures. This formulation was applied to numerous numerical examples of non-woven fabrics. As CSFEM schemes do not require coordinate transformation, spurious modes and numerical instabilities are prevented using bilinear quadrilateral element subdivided into two, three and four smoothing cells. An improvement of the original CSFEM formulation was made regarding the calculation of outward unit normal vectors, which allowed to remove the… More >