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Article
Publication date: 1 June 1997

Jaroslav Mackerle

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…

5566

Abstract

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

Details

Engineering Computations, vol. 14 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 12 June 2017

Chuanping Zhang, Fei Yu, Honggang Duan and Yuan Chen

The purpose of this paper is to design a glass handling robot and conduct a finite element analysis and structural optimization to solve the automation handling problem of…

Abstract

Purpose

The purpose of this paper is to design a glass handling robot and conduct a finite element analysis and structural optimization to solve the automation handling problem of large-scale glass production line and aiming at the phenomenon that the vibration of robot manipulator may result in breakage of glass products, especially the fragile chemical or medical glassware. Making modal analysis for the robot is to determine its natural frequencies and vibration modes and lay a foundation for the transient analysis to study the vibration shock response of the robot during its start-up and emergency stop operation.

Design/methodology/approach

First, a 3D model of the robot is established according to the requirements of the production field and a finite element model is built on the basis of the 3D model. Then the modal and transient analyses of the robot are carried out according to the fact that the maximum vibration impact of the robot usually appears at the start and emergency stop.

Findings

The structure of the robot is improved according to the results of finite element analysis. The dynamic analysis results show that the improved robot’s ability to resist deformation under the impact of vibration shock is enhanced, and the robot can operate smoothly and meet the requirements of design in industrial environments.

Originality/value

The research results avoided the damage caused by the vibration and improved the service life of the robot, providing a foundation for the structural design and mass production of the glass handling robot.

Details

International Journal of Structural Integrity, vol. 8 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 27 April 2020

Prabhu Sundaramoorthy, Balaji M., Suresh K., Ezhilventhan Natesan and Mohan K.

The main purpose of this research is to investigate finite-element analysis (FEA) on flux reversal-free stator switched reluctance motor (FRFSSRM) for industrial…

Abstract

Purpose

The main purpose of this research is to investigate finite-element analysis (FEA) on flux reversal-free stator switched reluctance motor (FRFSSRM) for industrial applications. The vibration analysis for an electrical machine is essential because of the acoustic noises. The acoustic noises originate by coincidence of natural frequencies of motor with the vibration frequencies.

Design/methodology/approach

The identification with the performance for FRFSRM by torque ripple, vibration. The vibration of the machine is because of unbalanced electromagnetic forces. The mutual coupled winding and a common pole between two adjacent exciting poles reduce these unbalanced forces.

Findings

The accelerometer is used to monitor the vibration amplitude in transient mode. A comparison study shows that the vibration is less in the E-core SRM than in the conventional flux reversal SRM.

Originality/value

The shorter flux path reduces the torque ripple and vibration content in SRM. This research article mainly focuses on the parameters such as vibration and torque ripple. The vibration of FRFSRM is identified by accelerometer; ANSYS Package predicts the simulation of the vibration measurement. The dynamic behaviors of this E-core SRM model with rated conditions the vibration had predicted.

Details

Circuit World, vol. 46 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 12 October 2022

Yongliang Wang, Jiansong Hu, David Kennedy, Jianhui Wang and Jiali Wu

Moderately thick circular cylindrical shells are widely used as supporting structures or storage cavities in structural engineering, rock engineering, and aerospace…

Abstract

Purpose

Moderately thick circular cylindrical shells are widely used as supporting structures or storage cavities in structural engineering, rock engineering, and aerospace engineering. In practical engineering, shells often work with micro-cracks or defects. The existence of micro-crack damage may result in the disturbance of dynamic behaviours and even induce accidental dynamic disasters. The free vibration frequency and mode are important parameters for the dynamic performance and damage identification analysis. In particular, stiffness weakening of the local damage region leads to significant changes in the vibration mode, which makes it difficult for the mesh generated in the conventional finite element method to capture a high-precision solution of the local oscillation.

Design/methodology/approach

In response to the above problems, this study developed an adaptive finite element method and a crack damage characterisation method for moderately thick circular cylindrical shells. By introducing the inverse power iteration method, error estimation, and mesh subdivision refinement technique for the analysis of finite element eigenvalue problems, an adaptive computation scheme was constructed for the free vibration problem of moderately thick circular cylindrical shells with circumferential crack damage.

Findings

Based on typical numerical examples, the established adaptive finite element solution for the free vibration of moderately thick circular cylindrical shells demonstrated its suitability for solving the high-precision free vibration frequency and mode of cylindrical shell structures. The any order frequency and mode shape of cracked cylindrical shells under the conditions of different ring wave numbers, crack locations, crack depths, and multiple cracks were successfully solved. The influences of the location, depth, and number of cracks on the disturbance of dynamic behaviours were analysed.

Originality/value

This study can be used as a reference for the adaptive finite element solution of free vibration of moderately thick circular cylindrical shells with cracks and lays the foundation for further development of a high-performance computation method suitable for the dynamic disturbance and damage identification analysis of general cracked structures.

Article
Publication date: 18 March 2022

Donghai Wang, Wei Sun, Zhihui Gao and Hui Li

In many cases, the external pipelines of aero-engine are subjected to random excitation. The purpose of this paper is to reduce the vibration response of the pipeline…

Abstract

Purpose

In many cases, the external pipelines of aero-engine are subjected to random excitation. The purpose of this paper is to reduce the vibration response of the pipeline system effectively by adjusting the hoop layout.

Design/methodology/approach

In this paper, a spatial pipeline supported by multi-hoops is taken as the object, the methods of solution of the vibration response of the pipeline system by using pseudo excitation and hoop layouts optimization with amplitude reduction of vibration response as the goal are presented. First, the finite element model of the spatial pipeline system is presented. Then, an optimization model spatial pipeline is established. Finally, a case study is carried out to prove the rationality of the random vibration response analysis of the pipeline system. Furthermore, the proposed optimization model and genetic algorithm are applied to optimize the hoop layout.

Findings

The results show that the maximum response variance after optimization is reduced by 32.8%, which proves the rationality of the developed hoop layout optimization method.

Originality/value

The pseudo excitation method is used to solve the vibration response of aero-engine pipeline system, and the optimization of the hoop layout for aero-engine spatial pipelines under random excitation to reduce random vibration response is studied systematically.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 8
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 4 July 2016

Marcos Arndt, Roberto Dalledone Machado and Adriano Scremin

The purpose of this paper is devoted to present an accurate assessment for determine natural frequencies for uniform and non-uniform Euler-Bernoulli beams and frames by an…

Abstract

Purpose

The purpose of this paper is devoted to present an accurate assessment for determine natural frequencies for uniform and non-uniform Euler-Bernoulli beams and frames by an adaptive generalized finite element method (GFEM). The present paper concentrates on developing the C1 element of the adaptive GFEM for vibration analysis of Euler-Bernoulli beams and frames.

Design/methodology/approach

The variational problem of free vibration is formulated and the main aspects of the adaptive GFEM are presented and discussed. The efficiency and convergence of the proposed method in vibration analysis of uniform and non-uniform Euler-Bernoulli beams are checked. The application of this technique in a frame is also presented.

Findings

The present paper concentrates on developing the C1 element of the adaptive GFEM for vibration analysis of Euler-Bernoulli beams and frames. The GFEM, which was conceived on the basis of the partition of unity method, allows the inclusion of enrichment functions that contain a priori knowledge about the fundamental solution of the governing differential equation. The proposed enrichment functions are dependent on the geometric and mechanical properties of the element. This approach converges very fast and is able to approximate the frequency related to any vibration mode.

Originality/value

The main contribution of the present study consisted in proposing an adaptive GFEM for vibration analysis of Euler-Bernoulli uniform and non-uniform beams and frames. The GFEM results were compared with those obtained by the h and p-versions of FEM and the c-version of the CEM. The adaptive GFEM has shown to be efficient in the vibration analysis of beams and has indicated that it can be applied even for a coarse discretization scheme in complex practical problems.

Details

Engineering Computations, vol. 33 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 14 February 2022

Young-Min Kwon, Sung-Boo Hong, Jae-Sang Park and Yu-Been Lee

The purpose of this study is to use the individual blade pitch control (IBC), reduce actively both the rotor hub vibratory loads and airframe vibration responses for the…

Abstract

Purpose

The purpose of this study is to use the individual blade pitch control (IBC), reduce actively both the rotor hub vibratory loads and airframe vibration responses for the lift-offset compound helicopter at a high-speed flight condition.

Design/methodology/approach

The Sikorsky X2 technology demonstrator (X2TD) is used as the lift-offset compound helicopter. The X2TD lift-offset rotor is modelled and its rotor hub vibratory loads at a flight speed of 250 knots are predicted using a rotorcraft comprehensive analysis code, CAMRAD II, and the airframe structural dynamics is represented with a finite element analysis code, MSC.NASTRAN. When the propulsive trim methodology is applied for rotor trim, the best input condition for IBC using multiple harmonic inputs is searched to reduce the rotor vibration, while the rotor aerodynamic performance (the rotor effective lift-to-drag ratio) is improved or maintained at least. Finally, the reduction in airframe vibration responses is investigated when the best input condition for IBC with multiple harmonics is applied to the lift-offset rotor.

Findings

When the IBC with the single harmonic input using the 2/rev actuation frequency, amplitude of 2° and control phase angle of 120° (2P/2°/120°) is considered for X2TD rotor, the rotor vibration is reduced by about 26.37% only and the rotor effective lift-to-drag ratio increases slightly by 0.98%. When X2TD rotor uses the IBC with multiple harmonic inputs (2P/2°/45° + 5P/1°/90°), the rotor hub vibratory loads and airframe vibration responses are reduced by 44.69% and from 0.48 to 79.10%, respectively, while rotor effective lift-to-drag ratio is improved by 0.77%, as compared to the baseline without IBC.

Originality/value

This study is the first study to use the 2/rev actuation for IBC to the four-bladed lift-offset coaxial rotor and to investigate to obtain simultaneously the rotor vibration reduction, rotor performance improvement and airframe vibration reduction, using IBC with multiple harmonic inputs.

Article
Publication date: 1 April 2006

Aparecido Carlos Gonçalves, Rodrigo Carvalho Cunha and Daniel Fabiano Lago

The purpose of the paper is to provide information on wear debris on oil and vibration analysis as predictive maintenance techniques in reducer.

Abstract

Purpose

The purpose of the paper is to provide information on wear debris on oil and vibration analysis as predictive maintenance techniques in reducer.

Design/methodology/approach

The estate of a reducer is verified by analyzing the vibration and oil conditions of a test rig under well‐designed conditions utilizing some predictive variables.

Findings

According to the vibration and oil analysis it is found out what it was happening into the reducer without disassembling it.

Practical implications

This paper demonstrates the use of oil debris analysis and vibration analysis as a technique that enhances preventive maintenance practices. The paper helps practitioners to utilize these techniques more effectively.

Originality/value

This paper gives information about two predictive maintenance techniques with a test rig.

Details

Journal of Quality in Maintenance Engineering, vol. 12 no. 2
Type: Research Article
ISSN: 1355-2511

Keywords

Article
Publication date: 1 June 2010

Pratesh Jayaswal, S.N. Verma and A.K. Wadhwani

The objective of this paper is to provide a brief review of recent developments in the area of applications of ANN, Fuzzy Logic, and Wavelet Transform in fault diagnosis…

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Abstract

Purpose

The objective of this paper is to provide a brief review of recent developments in the area of applications of ANN, Fuzzy Logic, and Wavelet Transform in fault diagnosis. The purpose of this work is to provide an approach for maintenance engineers for online fault diagnosis through the development of a machine condition‐monitoring system.

Design/methodology/approach

A detailed review of previous work carried out by several researchers and maintenance engineers in the area of machine‐fault signature‐analysis is performed. A hybrid expert system is developed using ANN, Fuzzy Logic and Wavelet Transform. A Knowledge Base (KB) is created with the help of fuzzy membership function. The triangular membership function is used for the generation of the knowledge base. The fuzzy‐BP approach is used successfully by using LR‐type fuzzy numbers of wavelet‐packet decomposition features.

Findings

The development of a hybrid system, with the use of LR‐type fuzzy numbers, ANN, Wavelets decomposition, and fuzzy logic is found. Results show that this approach can successfully diagnose the bearing condition and that accuracy is good compared with conventionally EBPNN‐based fault diagnosis.

Practical implications

The work presents a laboratory investigation carried out through an experimental set‐up for the study of mechanical faults, mainly related to the rolling element bearings.

Originality/value

The main contribution of the work has been the development of an expert system, which identifies the fault accurately online. The approaches can now be extended to the development of a fault diagnostics system for other mechanical faults such as gear fault, coupling fault, misalignment, looseness, and unbalance, etc.

Details

Journal of Quality in Maintenance Engineering, vol. 16 no. 2
Type: Research Article
ISSN: 1355-2511

Keywords

Article
Publication date: 16 April 2018

Yan Zhao, L.T. Si and H. Ouyang

A novel frequency domain approach, which combines the pseudo excitation method modified by the authors and multi-domain Fourier transform (PEM-FT), is proposed for…

Abstract

Purpose

A novel frequency domain approach, which combines the pseudo excitation method modified by the authors and multi-domain Fourier transform (PEM-FT), is proposed for analyzing nonstationary random vibration in this paper.

Design/methodology/approach

For a structure subjected to a nonstationary random excitation, the closed-form solution of evolutionary power spectral density of the response is derived in frequency domain.

Findings

The deterministic process and random process in an evolutionary spectrum are separated effectively using this method during the analysis of nonstationary random vibration of a linear damped system, only modulation function of the system needs to be estimated, which brings about a large saving in computational time.

Originality/value

The method is general and highly flexible as it can deal with various damping types and nonstationary random excitations with different modulation functions.

Details

Engineering Computations, vol. 35 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

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