检索结果-内蒙古大学图书馆

Vibration analysis of piezoelectric laminated slightly curved beams using distributed transfer function method

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES 2009年第6期46卷 1564-1573页

作者： Susanto, Ken Univ So Calif Dept Mech Engn Los Angeles CA 90089 USA

Piezoelectric laminated slightly curved beams (PLSCB) is currently one of the most popular actuators used in smart structure applications due to the fact that these actuators are small, lightweight, quick response and relatively high force output. This paper presents an analytical model of PLSCB, which includes the computation of natural frequencies, mode shapes and transfer function formulation using the distributed transfer function method (DTFM). By setting the radius of curvature of the proposed model to infinity, a piezoelectric laminated straight beams (PLSB) model can be obtained. The DTFM is applied and extended to carry out the transfer function formulation of the PLSCB and PLSB models. This method will be used to solve for the natural frequencies, mode shapes and transfer functions of the PLSCB and PLSB models in exact and closed form solution without using truncated series of particular comparison or admissible functions. The natural frequencies of the cantilevered PLSCB and PLSB are calculated by the DTFM and the Rayleigh-Ritz method. The analysis indicates that the stretching-bending coupling due to curvature has a considerable effect on the frequency parameters. Increasing the radius of curvature of the PLSCB has its largest effect on the natural frequencies. But the inhomogeneity of the boundary conditions does not have any effects on the natural frequencies or system spectrum due to the both receptance and boundary transfer functions have the same characteristic equations. The method can also be generalized to the vibration analysis of non-piezoelectric composite beams with arbitrary boundary conditions. (C) 2008 Elsevier Ltd. All rights reserved.

关键词： Piezoelectric laminated slightly curved beams Natural frequencies Vibration modes distributed transfer function method Piezoelectric laminated straight beams Piezoelectric composite beams Boundary transfer function

来源：评论

学校读者我要写书评

暂无评论

SEMI-ANALYTICAL SOLUTION OF TWO-DIMENSIONAL ELASTICITY PROBLEMS BY FINITE DIFFERENCE-distributed transfer function method

引用

INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS 2010年第2期10卷 315-334页

作者： Yang, Yaubin Yang, Bingen Univ So Calif Dept Aerosp & Mech Engn Los Angeles CA 90089 USA

A semi-analytical solution method, called the Finite Difference-distributed transfer function method, is developed for static and dynamic problems of two-dimensional elastic bodies composed of multiple rectangular subregions. In the development, the original two-dimensional elasticity problem is first reduced into a one-dimensional boundary-value problem by finite difference;the exact solution of the reduced problem is then obtained by using the distributed transfer functions of the elastic continuum. The proposed technique, which combines the simplicity of finite difference and the closed form of analytical solutions, is capable of handling arbitrary boundary conditions, delivers highly accurate solutions for static and dynamic problems, and is computationally efficient. The proposed method is illustrated on a square region and an L-shaped region.

关键词： Elasticity static and dynamic problems multi-body regions finite difference distributed transfer function method

来源：评论

学校读者我要写书评

暂无评论

Structural dynamic responses of a stripped solar sail subjected to solar radiation pressure

引用

Chinese Journal of Aeronautics 2020年第8期33卷 2204-2211页

作者： Junhui ZHANG Na WU An TONG Yinghua LIU School of Civil Engineering North China University of TechnologyBeijing 100144China School of Aerospace Engineering Tsinghua UniversityBeijing 100144China

The stripped solar sail whose membrane is divided into separate narrow membrane strips is believed to have the best structural *** this paper,the stripped solar sail structure is regarded as an assembly made by connecting a number of boom-strip components in *** the coupling effects between booms and membrane strips,an exact and semianalytical method to calculate structural dynamic responses of the stripped solar sail subjected to solar radiation pressure is *** case study of a 100 m stripped solar sail shows that the stripped architecture helps to reduce the static deflections and amplitudes of the steady-state dynamic *** prestress of the membrane strips will decrease stiffness of the sail and increase amplitudes of the steady-state dynamic *** thickness of the boom will benefit to stability of the sail and reduce the resonant *** proposed semi-analytical method provides an efficient analysis tool for structure design and attitude control of the stripped solar sail.

关键词： distributed transfer function method Frequency response Solar radiation pressure Solar sail Structural dynamic response

来源：评论

学校读者我要写书评

暂无评论

Investigation of boundary flexibility on the performance of piezoelectric vibration energy harvesting beam systems by DTFM

引用

JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES 2023年第1期34卷 47-64页

作者： Amoozegar, Shahram Tan, Chin An Wayne State Univ Dept Mech Engn 5050 Anthony Wayne Dr Detroit MI 48202 USA

The purpose of this paper is to investigate the effect of boundary flexibility on the performance of piezoelectric vibration energy harvester (PVEH) beam systems, which has not been studied comprehensively in the literature despite its importance. The coupled electromechanical equations of motion of a piezoelectric cantilever beam with a tip mass are established, with the base boundary constrained by translational and rotational springs. An exact closed-form solution of the frequency response function (FRF) of the PVEH is obtained by the distributed transfer function method (DTFM). The DTFM is a systematic powerful tool for the dynamic analysis of distributed parameter continua with non-classical boundary conditions, intermediate constraints, coupled fields, and non-proportional damping without adding much complexity to the solution formulation. Moreover, the DTFM computes the derivatives of the response, that is, the strains, which are required in the electromechanical coupling formulation, simultaneously without any differentiation. Numerical results showing the effects of boundary flexibility on energy harvesting efficiency are presented. A first-order rational function relating the boundary stiffness parameters and the harvesting efficiency is determined by nonlinear curve fitting of the calculated data. Physical insights and applicability of this analytical function for end-of-line quality check of the boundary of PVEH are discussed.

关键词： Piezoelectric vibration energy harvesting non-ideal boundary condition support flexibility distributed transfer function method coupled electromechanical modeling power harvesting efficiency

来源：评论

学校读者我要写书评

暂无评论

Medium-Frequency Vibration Analysis of Timoshenko Beam Structures

引用

INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS 2020年第13期20卷

作者： Zhang, Yichi Yang, Bingen Univ Southern Calif Dept Aerosp & Mech Engn Los Angeles CA 90089 USA

Medium-frequency (mid-frequency) vibration analysis of complex structures plays an important role in automotive, aerospace, mechanical, and civil engineering. Flexible beam structures modeled by the classical Euler-Bernoulli beam theory have been widely used in various engineering problems. A kinematic hypothesis made in the Euler-Bernoulli beam theory is that the plane sections of a beam normal to its neutral axis remain planes after the beam experiences bending deformation, which neglects shear deformation. However, previous investigations found out that the shear deformation of a beam (even with a large slenderness ratio) becomes noticeable in high-frequency vibrations. The Timoshenko beam theory, which describes both bending deformation and shear deformation, would naturally be more suitable for medium-frequency vibration analysis. Nevertheless, vibrations of Timoshenko beam structures in a medium frequency region have not been well studied in the literature. This paper presents a new method for mid-frequency vibration analysis of two-dimensional Timoshenko beam structures. The proposed method, which is called the augmented distributed transfer function method (DTFM), models a Timoshenko beam structure by a spatial state-space formulation in the s-domain. The augmented DTFM determines the frequency response of a beam structure in an exact and analytical form, in any frequency region covering low, middle, or high frequencies. Meanwhile, the proposed method provides the local information of a beam structure, such as displacement, shear deformation, bending moment and shear force at any location, which otherwise would be very difficult with energy-based methods. The medium-frequency analysis by the augmented DTFM is validated in numerical examples, where the efficiency and accuracy of the proposed method is demonstrated. Also, the effects of shear deformation on the dynamic behaviors of a beam structure at medium frequencies are examined through comparison of the T

关键词： Structural dynamics beam structures medium-frequency vibrations mid-frequency analysis Timoshenko beam theory shear deformation distributed transfer function method analytical solution method

来源：评论

学校读者我要写书评

暂无评论

Parametric study of rocking cores-moment frames with supplemental viscous damping and self-centering devices using a distributed parameter model

引用

SOIL DYNAMICS AND EARTHQUAKE ENGINEERING 2019年第Aug.期123卷 304-319页

作者： Wu, Dayang Lu, Xilin Zhao, Bin Tongji Univ State Key Lab Disaster Reduct Civil Engn Shanghai 200092 Peoples R China

A distributed parameter model is proposed for the rocking cores-moment frames (RCMFs) with supplemental viscous damping and self-centering devices. In this model, the moment frame and rocking cores are simplified as a shear beam and a flexural beam, respectively, while viscous damping and self-centering devices are substituted by rotational constraint with linear viscous damping and elastic stiffness. Three nondimensional parameters, frame-core stiffness parameter, base-rotation fixity parameter and damping parameter, are introduced to describe the dynamic behavior of the full physical structural system. Closed-form solutions for complex modal shapes are derived, and then parametric study is conducted to explore the effects of these three parameters on modal damping ratios, eigenvalues, complex modal shapes, and drift concentration factor. Explicit expressions of modal damping ratios with these three parameters are established through curve-fitting technique that can be conveniently used for engineering practice. Frequency responses of base shear forces and moments are obtained using the distributed transfer function method. It is concluded that the modal damping ratios are significantly affected by these three parameters, and their peak values will be remarkably reduced as the increasing of the frame-core stiffness and base-rotation fixity. For design purpose, appropriate ranges of these three parameters are recommended to achieve better drift uniformity control, response reduction, and higher modes effect mitigation. The proposed model and conclusions of the parametric study can be used as a tool for rapidly evaluating seismic performance in a preliminary design phase of the RCMFs.

关键词： Rocking cores-moment frames distributed parameter model Modal damping ratio distributed transfer function method Drift concentration factor Higher modes effect

来源：评论

学校读者我要写书评

暂无评论

Closed-form analytical solutions of transient heat conduction in hollow composite cylinders with any number of layers

引用

INTERNATIONAL JOURNAL OF HEAT AND MASS transfer 2017年第PartA期108卷 907-917页

作者： Yang, Bingen Liu, Shibing Univ Southern Calif Dept Aerosp & Mech Engn Los Angeles CA 90089 USA

Conventional analytical methods for transient heat conduction solutions, due to complicated derivations and formidable calculations, have been limited to composite bodies with two or three layers. Developed in this work is a new analytical solution method for transient heat conduction in hollow composite cylinders with an arbitrary number of layers and subject to general boundary conditions. In this method, a distributed transfer function formulation gives an s-domain solution of a composite cylinder and inverse Laplace transform of the s-domain solution via a newly derived residue formula yields the transient solution of the cylinder in an explicit and closed form. Unlike conventional analytical methods, the proposed method does not require different derivations for different cylinder configurations (such as number of layers, boundary conditions and thermal resistance at layer interfaces). Because it only involves two by-two matrices in the solution process, the proposed method is highly efficient in computation, as demonstrated in numerical examples. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： Heat conduction Composite media Multilayer cylinders Analytical solutions Laplace transform distributed transfer function method

来源：评论

学校读者我要写书评

暂无评论

A closed-form analytical solution method for vibration analysis of elastically connected double-beam systems

引用

COMPOSITE STRUCTURES 2019年 212卷 598-608页

作者： Liu, Shibing Yang, Bingen Hyperloop One 2159 Bay St Los Angeles CA 90021 USA Univ Southern Calif Dept Aerosp & Mech Engn Los Angeles CA 90089 USA

A double-beam system, which is a structure composed of two parallel beams that are interconnected by a viscoelastic layer, is seen in many engineering applications. Vibration analysis is essentially important for the safe and reliable operation, and optimal design of such dynamic systems. This paper presents an analytical method, the distributed transfer function method (DTFM), for modeling and vibration analysis of double-beam systems with arbitrary beam linear densities and flexural rigidities, and general boundary conditions. Exact closed-form analytical solutions for natural frequencies, mode shapes, and steady-state responses to periodic excitations are determined. The proposed method is applicable to a double-beam system with lower beam being fully, partially, or not supported by an elastic foundation. Through numerical study, the accuracy and efficiency of the proposed method are validated, and the effects of the stiffness, length, and location of an elastic foundation are investigated. It is shown that the DTFM is a useful tool for optimal design of elastically connected double-beam systems.

关键词： Vibration Double-beam system Elastic foundation distributed transfer function method Analytical solution Arbitrary boundary conditions

来源：评论

学校读者我要写书评

暂无评论

Optimal placement of water-lubricated rubber bearings for vibration reduction of flexible multistage rotor systems

引用

JOURNAL OF SOUND AND VIBRATION 2017年 407卷 332-349页

作者： Liu, Shibing Yang, Bingen Hyperloop One 2159 Bay St Los Angeles CA 90021 USA Univ Southern Calif Dept Aerosp & Mech Engn Los Angeles CA 90089 USA

Flexible multistage rotor systems with water-lubricated rubber bearings (WLRBs) have a variety of engineering applications. Filling a technical gap in the literature, this effort proposes a method of optimal bearing placement that minimizes the vibration amplitude of a WLRB-supported flexible rotor system with a minimum number of bearings. In the development, a new model of WLRBs and a distributed transfer function formulation are used to define a mixed continuous-and-discrete optimization problem. To deal with the case of uncertain number of WLRBs in rotor design, a virtual bearing method is devised. Solution of the optimization problem by a real-coded genetic algorithm yields the locations and lengths of water-lubricated rubber bearings, by which the prescribed operational requirements for the rotor system are satisfied. The proposed method is applicable either to preliminary design of a new rotor system with the number of bearings unfore known or to redesign of an existing rotor system with a given number of bearings. Numerical examples show that the proposed optimal bearing placement is efficient, accurate and versatile in different design cases. (C) 2017 Elsevier Ltd. All rights reserved.

关键词： Water lubricated rubber bearing Optimization Vibration Multistage rotor systems Flexible rotor-bearing systems distributed transfer function method

来源：评论

学校读者我要写书评

暂无评论

EXACT TRANSIENT VIBRATION OF NONUNIFORM BARS, SHAFTS AND STRINGS GOVERNED BY WAVE EQUATIONS

引用

INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS 2012年第4期12卷 1250022-1-1250022-20页

作者： Yang, B. Noh, K. Univ So Calif Dept Aerosp & Mech Engn Los Angeles CA 90089 USA

A new analytical method is developed for transient solutions for bars in longitudinal vibration, shafts in torsional vibration and strings in transverse vibration. These vibrating continua have nonuniform distributions of geometric and material properties, and are governed by second-order partial differential equations (wave equations). Based on a transfer function formulation and a residue formula, the proposed method delivers exact solutions for several types of nonuniform systems subject to external, boundary and initial disturbances. The proposed method does not need system eigenfunctions, and is numerically efficient as it only involves simple operations of two-by-two matrices.

关键词： distributed vibrating systems nonuniform systems bars, shafts strings transient vibration analytical methods Laplace transform Green's functions distributed transfer function method

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：