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Hindawi Publishing Corporation Mathematical Problems in Engineering Volume 2013, Article ID 418374, 26 pages http://dx.doi.org/10.1155/2013/418374 Research Article Vibration, Stability, and Resonance of Angle-Ply Composite Laminated Rectangular Thin Plate under Multiexcitations M. Sayed 1,2 and A. A. Mousa 1,3 1 Department of Mathematics and Statistics, Faculty of Science, Taif University, P.O. Box 888, Al-Taif, Saudi Arabia 2 Department of Engineering Mathematics, Faculty of Electronic Engineering, Menou๏ฌa University, Menouf, Egypt 3 Department of Basic Engineering Sciences, Faculty of Engineering, Menou๏ฌa University, Shibin El-Kom, Egypt Correspondence should be addressed to M. Sayed; moh 6 [email protected] Received 10 November 2012; Revised 15 April 2013; Accepted 1 May 2013 Academic Editor: Dane Quinn Copyright ยฉ 2013 M. Sayed and A. A. Mousa. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. An analytical investigation of the nonlinear vibration of a symmetric cross-ply composite laminated piezoelectric rectangular plate under parametric and external excitations is presented. e method of multiple time scale perturbation is applied to solve the non- linear di๏ฌ€erential equations describing the system up to and including the second-order approximation. All possible resonance cases are extracted at this approximation order. e case of 1 : 1 : 3 primary and internal resonance, where ฮฉ 3 โ‰… 1 , 2 โ‰… 1 , and 3 โ‰… 3 1 , is considered. e stability of the system is investigated using both phase-plane method and frequency response curves. e in๏ฌ‚u- ences of the cubic terms on nonlinear dynamic characteristics of the composite laminated piezoelectric rectangular plate are studied. e analytical results given by the method of multiple time scale is veri๏ฌed by comparison with results from numerical integration of the modal equations. Reliability of the obtained results is veri๏ฌed by comparison between the ๏ฌnite di๏ฌ€erence method (FDM) and Runge-Kutta method (RKM). It is quite clear that some of the simultaneous resonance cases are undesirable in the design of such system. Such cases should be avoided as working conditions for the system. Variation of the parameters 1 , 2 , 7 , 8 , 1 , 2 , 1 , 2 leads to multivalued amplitudes and hence to jump phenomena. Some recommendations regarding the di๏ฌ€erent parameters of the system are reported. Comparison with the available published work is reported. 1. Introduction Composite laminated plates that are widely used in several engineering ๏ฌelds such as machinery, shipbuilding, aircra๏ฌ…, automobiles, robot arm, watercra๏ฌ…-hydropower, and wings of helicopters are made of the angle-ply composite laminated plates. Several researchers have focused their attention on studying the nonlinear dynamics, bifurcations, and chaos of the composite laminated plates. Internal resonance has been found in many engineering problems in which the natural frequencies of the system are commensurable. Ye et al. [1] investigated the local and global nonlinear dynamics of a parametrically excited symmetric cross-ply composite laminated rectangular thin plate under parametric excitation. e study is focused on the case of 1 : 1 internal resonance and primary parametric resonance. Zhang [2] dealt with the global bifurcations and chaotic dynamics of a parametrically excited, simply supported rectangular thin plate. e method of multiple scales is used to obtain the averaged equations. e case of 1 : 1 internal resonance and primary parametric resonance is considered. Guo et al. [3] studied the nonlinear dynamics of a four-edge simply supported angle-ply composite laminated rectangular thin plate excited by both the in-plane and transverse loads. e asymptotic perturbation method is used to derive the four averaged equations under 1 : 1 internal resonance. Zhang et al. [4] investigated the local and global bifurcations of a para- metrically and externally excited simply supported rectan- gular thin plate under simultaneous transversal and in-plane excitations. e studies are focused on the case of 1 : 1 internal resonance and primary parametric resonance. Tien et al. [5] applied the averaging method and Melnikov technique to study local, global bifurcations and chaos of a two-degrees- of-freedom shallow arch subjected to simple harmonic

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  • Hindawi Publishing CorporationMathematical Problems in EngineeringVolume 2013, Article ID 418374, 26 pageshttp://dx.doi.org/10.1155/2013/418374

    Research ArticleVibration, Stability, and Resonance of Angle-Ply CompositeLaminated Rectangular Thin Plate under Multiexcitations

    M. Sayed1,2 and A. A. Mousa1,3

    1 Department of Mathematics and Statistics, Faculty of Science, Taif University, P.O. Box 888, Al-Taif, Saudi Arabia2Department of Engineering Mathematics, Faculty of Electronic Engineering, Menoufia University, Menouf, Egypt3 Department of Basic Engineering Sciences, Faculty of Engineering, Menoufia University, Shibin El-Kom, Egypt

    Correspondence should be addressed to M. Sayed; moh 6 [email protected]

    Received 10 November 2012; Revised 15 April 2013; Accepted 1 May 2013

    Academic Editor: Dane Quinn

    Copyright ยฉ 2013 M. Sayed and A. A. Mousa. This is an open access article distributed under the Creative Commons AttributionLicense, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properlycited.

    An analytical investigation of the nonlinear vibration of a symmetric cross-ply composite laminated piezoelectric rectangular plateunder parametric and external excitations is presented.Themethod of multiple time scale perturbation is applied to solve the non-linear differential equations describing the systemup to and including the second-order approximation. All possible resonance casesare extracted at this approximation order.The case of 1 : 1 : 3 primary and internal resonance, whereฮฉ

    3โ‰… ๐œ”1,๐œ”2โ‰… ๐œ”1, and๐œ”

    3โ‰… 3๐œ”1,

    is considered. The stability of the system is investigated using both phase-plane method and frequency response curves. The influ-ences of the cubic terms onnonlinear dynamic characteristics of the composite laminated piezoelectric rectangular plate are studied.The analytical results given by the method of multiple time scale is verified by comparison with results from numerical integrationof themodal equations. Reliability of the obtained results is verified by comparison between the finite differencemethod (FDM) andRunge-Kutta method (RKM). It is quite clear that some of the simultaneous resonance cases are undesirable in the design of suchsystem. Such cases should be avoided as working conditions for the system. Variation of the parameters ๐œ‡

    1, ๐œ‡2, ๐›ผ7, ๐›ฝ8, ๐œ”1, ๐œ”2, ๐‘“1, ๐‘“2

    leads to multivalued amplitudes and hence to jump phenomena. Some recommendations regarding the different parameters of thesystem are reported. Comparison with the available published work is reported.

    1. Introduction

    Composite laminated plates that are widely used in severalengineering fields such as machinery, shipbuilding, aircraft,automobiles, robot arm, watercraft-hydropower, and wingsof helicopters are made of the angle-ply composite laminatedplates. Several researchers have focused their attention onstudying the nonlinear dynamics, bifurcations, and chaos ofthe composite laminated plates.

    Internal resonance has been found in many engineeringproblems in which the natural frequencies of the system arecommensurable. Ye et al. [1] investigated the local and globalnonlinear dynamics of a parametrically excited symmetriccross-ply composite laminated rectangular thin plate underparametric excitation. The study is focused on the case of 1 : 1internal resonance and primary parametric resonance. Zhang[2] dealt with the global bifurcations and chaotic dynamics of

    a parametrically excited, simply supported rectangular thinplate. The method of multiple scales is used to obtain theaveraged equations. The case of 1 : 1 internal resonance andprimary parametric resonance is considered. Guo et al.[3] studied the nonlinear dynamics of a four-edge simplysupported angle-ply composite laminated rectangular thinplate excited by both the in-plane and transverse loads. Theasymptotic perturbation method is used to derive the fouraveraged equations under 1 : 1 internal resonance. Zhang et al.[4] investigated the local and global bifurcations of a para-metrically and externally excited simply supported rectan-gular thin plate under simultaneous transversal and in-planeexcitations.The studies are focused on the case of 1 : 1 internalresonance and primary parametric resonance. Tien et al. [5]applied the averaging method and Melnikov technique tostudy local, global bifurcations and chaos of a two-degrees-of-freedom shallow arch subjected to simple harmonic

  • 2 Mathematical Problems in Engineering

    excitation for case of 1 : 2 internal resonances. Sayed andMousa [6] investigated the influence of the quadratic andcubic terms on nonlinear dynamic characteristics of theangle-ply composite laminated rectangular plate with para-metric and external excitations. Two cases of the subhar-monic resonances cases in the presence of 1 : 2 internal reso-nances are considered.Themethod ofmultiple time scale per-turbation is applied to solve the nonlinear differential equa-tions describing the system up to and including the second-order approximation. Zhang et al. [7] gave further studies onthe nonlinear oscillations and chaotic dynamics of a para-metrically excited simply supported symmetric cross-plylaminated composite rectangular thin plate with the geo-metric nonlinearity and nonlinear damping. Zhang et al. [8]dealt with the nonlinear vibrations and chaotic dynamics ofa simply supported orthotropic functionally graded mate-rial (FGM) rectangular plate subjected to the in-plane andtransverse excitations together with thermal loading in thepresence of 1 : 2 : 4 internal resonance, primary parametricresonance, and subharmonic resonance of order 1/2. Zhanget al. [9] investigated the bifurcations and chaotic dynamics ofa simply supported symmetric cross-ply composite laminatedpiezoelectric rectangular plate subject to the transverse, in-plane excitations and the excitation loaded by piezoelectriclayers. Zhang and Li [10] analyzed the resonant chaoticmotions of a simply supported rectangular thin plate withparametrically and externally excitations using exponentialdichotomies and an averaging procedure. Zhang et al. [11]analyzed the chaotic dynamics of a six-dimensional nonlinearsystem which represents the averaged equation of a compos-ite laminated piezoelectric rectangular plate subjected to thetransverse, in-plane excitations and the excitation loaded bypiezoelectric layers. The case of 1 : 2 : 4 internal resonances isconsidered. Zhang and Hao [12] studied the global bifurca-tions and multipulse chaotic dynamics of the composite lam-inated piezoelectric rectangular plate by using the improvedextended Melnikov method. The multipulse chaotic motionsof the system are found by using numerical simulation, whichfurther verifies the result of theoretical analysis. Guo andZhang [13] studied the nonlinear oscillations and chaoticdynamics for a simply supported symmetric cross-ply com-posite laminated rectangular thin plate with parametric andforcing excitations. The case of 1 : 2 : 3 internal resonance isconsidered. The method of multiple scales is employed toobtain the six-dimensional averaged equation.The numericalmethod is used to investigate the periodic and chaoticmotions of the composite laminated rectangular thin plate.Eissa and Sayed [14โ€“16] and Sayed [17] investigated the effectsof different active controllers on simple and spring pendulumat the primary resonance via negative velocity feedback orits square or cubic. Sayed and Kamel [18, 19] investigated theeffects of different controllers on the vibrating system and thesaturation control to reduce vibrations due to rotor blade flap-ping motion. The stability of the system is investigated usingboth phase-plane method and frequency response curves.Sayed and Hamed [20] studied the response of a two-degree-of-freedom systemwith quadratic coupling under parametricand harmonic excitations. The method of multiple scaleperturbation technique is applied to solve the nonlinear

    differential equations and obtain approximate solutions up toand including the second-order approximations. Amer et al.[21] investigated the dynamical system of a twin-tail aircraft,which is described by two coupled second-order nonlin-ear differential equations having both quadratic and cubicnonlinearities under different controllers. Best active controlof the system has been achieved via negative accelera-tion feedback. The stability of the system is investigatedapplying both frequency response equations and phase-plane method. Hamed et al. [22] studied the nonlineardynamic behavior of a string-beam coupled system subjectedto external, parametric, and tuned excitations that are pre-sented.The case of 1 : 1 internal resonance between themodesof the beam and string, and the primary and combined reson-ance for the beam is considered. The method of multiplescales is applied to obtain approximate solutions up to andincluding the second-order approximations. All resonancecases are extracted and investigated. Stability of the systemis studied using frequency response equations and the phase-plane method. Awrejcewicz et al. [23โ€“25] studied the chaoticdynamics of continuous mechanical systems such as flexibleplates and shallow shells.The considered problems are solvedby the Bubnov-Galerkin, Ritz method with higher approxi-mations, and finite difference method. Convergence and val-idation of those methods are studied. Awrejcewicz et al. [26]investigated the chaotic vibrations of flexible nonlinear Euler-Bernoulli beams subjected to harmonic load andwith variousboundary conditions. Reliability of the obtained results isverified by the finite difference method and finite elementmethodwith the Bubnov-Galerkin approximation for variousboundary conditions and various dynamic regimes.

    In this paper, the perturbation method and stabilityof the composite laminated piezoelectric rectangular plateunder simultaneous transverse and in-plane excitations areinvestigated. The method of multiple scales are applied toobtain the second-order uniform asymptotic solutions. Allpossible resonance cases are extracted at this approximationorder. The study is focused on the case of 1 : 1 : 3 internalresonance and primary resonance.The stability of the systemand the effects of different parameters on system behaviorhave been studied using frequency response curves. Stabilityis performed of figures by solid and dotted lines. Theanalytical results given by the method of multiple timescale is verified by comparison with results from numericalintegration of the modal equations. It is quite clear thatsome of the simultaneous resonance cases are undesirable inthe design of such system. Such cases should be avoided asworking conditions for the system. Some recommendationsregarding the different parameters of the system are reported.Comparison with the available published work is reported.

    2. Mathematical Analysis

    Consider a simply supported four edges composite laminatedpiezoelectric rectangular plate of lengths ๐‘Ž, ๐‘ and thickness โ„Ž,as shown in Figure 1. The composite laminated piezoelectricrectangular plate is considered as regular symmetric cross-ply laminates with ๐‘› layers. A Cartesian coordinate system is

  • Mathematical Problems in Engineering 3

    y

    b

    q cosฮฉ3t

    q0 + qx cosฮฉ1t

    q1 + qy cosฮฉ2t

    x

    a

    Figure 1: The model of the composite laminated piezoelectricrectangular plate.

    located in the middle surface of the plate. Assume that ๐‘ข, V,and ๐‘ค represent the displacements of an arbitrary point ofthe composite laminated piezoelectric rectangular plate in the๐‘ฅ, ๐‘ฆ, and ๐‘ง directions, respectively. The in-plane excitationsare loaded along the ๐‘ฆdirection at ๐‘ฅ = 0 in the form๐‘ž0+ ๐‘ž๐‘ฅcosฮฉ1๐‘ก, and the excitations are loaded along the ๐‘ฅ

    direction at ๐‘ฆ = 0 in the form ๐‘ž1+ ๐‘ž๐‘ฆcosฮฉ2๐‘ก. The trans-

    verse excitation subjected to the composite laminated piezo-electric rectangular plate is represented by ๐‘ž cosฮฉ

    3๐‘ก. The

    dynamic electrical loading is expressed as ๐ธ๐‘งcosฮฉ4๐‘ก. Based

    on Reddyโ€™s third-order shear deformation plate theory [27],the displacement field at an arbitrary point in the compositelaminated plate is expressed as [13]

    ๐‘ข (๐‘ฅ, ๐‘ฆ, ๐‘ก) = ๐‘ข0(๐‘ฅ, ๐‘ฆ, ๐‘ก) + ๐‘ง๐œ‘

    ๐‘ฅ(๐‘ฅ, ๐‘ฆ, ๐‘ก) โˆ’ ๐‘ง

    3 4

    3โ„Ž2(๐œ‘๐‘ฅ+๐œ•๐‘ค0

    ๐œ•๐‘ฅ) ,

    (1a)

    V (๐‘ฅ, ๐‘ฆ, ๐‘ก) = V0(๐‘ฅ, ๐‘ฆ, ๐‘ก) + ๐‘ง๐œ‘

    ๐‘ฆ(๐‘ฅ, ๐‘ฆ, ๐‘ก) โˆ’ ๐‘ง

    3 4

    3โ„Ž2(๐œ‘๐‘ฆ+๐œ•๐‘ค0

    ๐œ•๐‘ฆ) ,

    (1b)

    ๐‘ค (๐‘ฅ, ๐‘ฆ, ๐‘ก) = ๐‘ค0(๐‘ฅ, ๐‘ฆ, ๐‘ก) , (1c)

    where ๐‘ข0, V0, and ๐‘ค

    0are the original displacement on the

    midplane of the plate in the๐‘ฅ,๐‘ฆ, and ๐‘งdirections, respectively.Let ๐œ‘๐‘ฅand ๐œ‘

    ๐‘ฆrepresent the midplane rotations of transverse

    normal about the ๐‘ฅ and ๐‘ฆ axes, respectively. From thevan Karman-type plate theory and Hamiltonโ€™s principle, thenonlinear governing equations of motion of the compositelaminated piezoelectric rectangular plate are given as follows[12]:

    ๐œ•๐‘๐‘ฅ๐‘ฅ

    ๐œ•๐‘ฅ+

    ๐œ•๐‘๐‘ฅ๐‘ฆ

    ๐œ•๐‘ฆ= ๐ผ0๏ฟฝฬˆ๏ฟฝ0+ ๐ฝ1๏ฟฝฬˆ๏ฟฝ๐‘ฅโˆ’4

    3โ„Ž2๐ผ3

    ๐œ•๏ฟฝฬˆ๏ฟฝ0

    ๐œ•๐‘ฅ, (2a)

    ๐œ•๐‘๐‘ฅ๐‘ฆ

    ๐œ•๐‘ฅ+

    ๐œ•๐‘๐‘ฆ๐‘ฆ

    ๐œ•๐‘ฆ= ๐ผ0Vฬˆ0+ ๐ฝ1๏ฟฝฬˆ๏ฟฝ๐‘ฆโˆ’4

    3โ„Ž2๐ผ3

    ๐œ•๏ฟฝฬˆ๏ฟฝ0

    ๐œ•๐‘ฆ, (2b)

    ๐œ•๐‘„๐‘ฅ

    ๐œ•๐‘ฅ+

    ๐œ•๐‘„๐‘ฆ

    ๐œ•๐‘ฆ+๐œ•

    ๐œ•๐‘ฅ(๐‘๐‘ฅ๐‘ฅ

    ๐œ•๐‘ค0

    ๐œ•๐‘ฅ+ ๐‘๐‘ฅ๐‘ฆ

    ๐œ•๐‘ค0

    ๐œ•๐‘ฆ)

    +๐œ•

    ๐œ•๐‘ฆ(๐‘๐‘ฅ๐‘ฆ

    ๐œ•๐‘ค0

    ๐œ•๐‘ฅ+ ๐‘๐‘ฆ๐‘ฆ

    ๐œ•๐‘ค0

    ๐œ•๐‘ฆ)

    +4

    3โ„Ž2(๐œ•2๐‘ƒ๐‘ฅ๐‘ฅ

    ๐œ•๐‘ฅ2+ 2

    ๐œ•2๐‘ƒ๐‘ฅ๐‘ฆ

    ๐œ•๐‘ฅ๐œ•๐‘ฆ+

    ๐œ•2๐‘ƒ๐‘ฆ๐‘ฆ

    ๐œ•๐‘ฆ2) + ๐‘ž

    = ๐ผ0๏ฟฝฬˆ๏ฟฝ0โˆ’16

    9โ„Ž4๐ผ6(๐œ•2๏ฟฝฬˆ๏ฟฝ0

    ๐œ•๐‘ฅ2+๐œ•2๏ฟฝฬˆ๏ฟฝ0

    ๐œ•๐‘ฆ2)

    +4

    3โ„Ž2[๐ผ3(๐œ•๏ฟฝฬˆ๏ฟฝ0

    ๐œ•๐‘ฅ+๐œ•Vฬˆ0

    ๐œ•๐‘ฆ) + ๐ฝ4(๐œ•๏ฟฝฬˆ๏ฟฝ๐‘ฅ

    ๐œ•๐‘ฅ+

    ๐œ•๏ฟฝฬˆ๏ฟฝ๐‘ฆ

    ๐œ•๐‘ฆ)] ,

    (2c)

    ๐œ•๐‘€๐‘ฅ๐‘ฅ

    ๐œ•๐‘ฅ+

    ๐œ•๐‘€๐‘ฅ๐‘ฆ

    ๐œ•๐‘ฆโˆ’ ๐‘„๐‘ฅ= ๐ฝ1๏ฟฝฬˆ๏ฟฝ0+ ๐‘˜2๏ฟฝฬˆ๏ฟฝ๐‘ฅโˆ’4

    3โ„Ž2๐ฝ4

    ๐œ•๏ฟฝฬˆ๏ฟฝ0

    ๐œ•๐‘ฅ, (2d)

    ๐œ•๐‘€๐‘ฅ๐‘ฆ

    ๐œ•๐‘ฅ+

    ๐œ•๐‘€๐‘ฆ๐‘ฆ

    ๐œ•๐‘ฆโˆ’ ๐‘„๐‘ฆ= ๐ฝ1Vฬˆ0+ ๐‘˜2๏ฟฝฬˆ๏ฟฝ๐‘ฆโˆ’4

    3โ„Ž2๐ฝ4

    ๐œ•๏ฟฝฬˆ๏ฟฝ0

    ๐œ•๐‘ฆ. (2e)

    Theboundary conditions of the simply supported rectangularcomposite laminated plate are expressed as follows:

    at ๐‘ฅ = 0, ๐‘ฅ = ๐‘Ž : ๐œ•๐‘ข๐œ•๐‘ฅ= 0,

    ๐‘ค = ๐‘ข = ๐œ‘๐‘ฅ= ๐œ‘๐‘ฆ= ๐‘€๐‘ฅ๐‘ฅ= ๐‘๐‘ฅ๐‘ฆ= ๐‘„๐‘ฅ= 0,

    (3a)

    at ๐‘ฆ = 0, ๐‘ฆ = ๐‘ : ๐œ•V๐œ•๐‘ฆ= 0,

    ๐‘ค = V = ๐‘๐‘ฅ๐‘ฆ= ๐‘€๐‘ฆ๐‘ฆ= ๐‘„๐‘ฆ= 0,

    (3b)

    โˆซ

    ๐‘

    0

    ๐‘๐‘ฅ๐‘ฅ

    ๐‘ฅ=0, ๐‘Ž๐‘‘๐‘ฆ = โˆซ

    ๐‘

    0

    (๐‘ž0+ ๐‘ž๐‘ฅcosฮฉ1๐‘ก) ๐‘‘๐‘ฆ, (3c)

    โˆซ

    ๐‘Ž

    0

    ๐‘๐‘ฆ๐‘ฆ

    ๐‘ฆ=0, ๐‘๐‘‘๐‘ฅ = โˆซ

    ๐‘Ž

    0

    (๐‘ž1+ ๐‘ž๐‘ฆcosฮฉ2๐‘ก) ๐‘‘๐‘ฅ. (3d)

    Applying the Galerkin procedure, we obtain that the dimen-sionless differential equations of motion for the simplysupported symmetric cross-ply rectangular thin plate areshown as follows [11, 28]:

    ๏ฟฝฬˆ๏ฟฝ1+ ๐œ‡1๏ฟฝฬ‡๏ฟฝ1+ ๐œ”2

    1๐‘ข1

    + (๐‘“11cosฮฉ1๐‘ก + ๐‘“12cosฮฉ2๐‘ก + ๐‘“14cosฮฉ4๐‘ก) ๐‘ข1

    + ๐›ผ1๐‘ข2

    1๐‘ข2+ ๐›ผ2๐‘ข2

    1๐‘ข3+ ๐›ผ3๐‘ข2

    2๐‘ข1+ ๐›ผ4๐‘ข2

    2๐‘ข3

    + ๐›ผ5๐‘ข2

    3๐‘ข1+ ๐›ผ6๐‘ข2

    3๐‘ข2+ ๐›ผ7๐‘ข3

    1+ ๐›ผ8๐‘ข3

    2

    + ๐›ผ9๐‘ข3

    3+ ๐›ผ10๐‘ข1๐‘ข2๐‘ข3

    = ๐‘“1cosฮฉ3๐‘ก,

    (4a)

  • 4 Mathematical Problems in Engineering

    ๏ฟฝฬˆ๏ฟฝ2+ ๐œ‡2๏ฟฝฬ‡๏ฟฝ2+ ๐œ”2

    2๐‘ข2

    + (๐‘“21cosฮฉ1๐‘ก + ๐‘“22cosฮฉ2๐‘ก + ๐‘“24cosฮฉ4๐‘ก) ๐‘ข2

    + ๐›ฝ1๐‘ข2

    1๐‘ข2+ ๐›ฝ2๐‘ข2

    1๐‘ข3+ ๐›ฝ3๐‘ข2

    2๐‘ข1+ ๐›ฝ4๐‘ข2

    2๐‘ข3

    + ๐›ฝ5๐‘ข2

    3๐‘ข1+ ๐›ฝ6๐‘ข2

    3๐‘ข2+ ๐›ฝ7๐‘ข3

    1+ ๐›ฝ8๐‘ข3

    2

    + ๐›ฝ9๐‘ข3

    3+ ๐›ฝ10๐‘ข1๐‘ข2๐‘ข3

    = ๐‘“2cosฮฉ3๐‘ก,

    (4b)

    ๏ฟฝฬˆ๏ฟฝ3+ ๐œ‡3๏ฟฝฬ‡๏ฟฝ3+ ๐œ”2

    3๐‘ข3

    + (๐‘“31cosฮฉ1๐‘ก + ๐‘“32cosฮฉ2๐‘ก + ๐‘“34cosฮฉ4๐‘ก) ๐‘ข3

    + ๐›พ1๐‘ข2

    1๐‘ข2+ ๐›พ2๐‘ข2

    1๐‘ข3+ ๐›พ3๐‘ข2

    2๐‘ข1+ ๐›พ4๐‘ข2

    2๐‘ข3

    + ๐›พ5๐‘ข2

    3๐‘ข1+ ๐›พ6๐‘ข2

    3๐‘ข2+ ๐›พ7๐‘ข3

    1+ ๐›พ8๐‘ข3

    2

    + ๐›พ9๐‘ข3

    3+ ๐›พ10๐‘ข1๐‘ข2๐‘ข3

    = ๐‘“3cosฮฉ3๐‘ก,

    (4c)

    where ๐‘ข1, ๐‘ข2, and ๐‘ข

    3are the vibration amplitudes of the com-

    posite laminated piezoelectric rectangular plate for the first-order, second-order, and the third-order modes, respectively,๐œ‡1, ๐œ‡2, and ๐œ‡

    3are the linear viscous damping coefficients,

    ๐œ”1, ๐œ”2, and ๐œ”

    3are the natural frequencies of the rectangular

    plate, andฮฉ1,ฮฉ2,ฮฉ3, andฮฉ

    4are the excitations frequencies.

    ๐‘“๐‘›1, ๐‘“๐‘›2, ๐‘“๐‘›3, and ๐‘“

    ๐‘›(๐‘› = 1, 2, 3) are the amplitudes of

    parametric and external excitation forces corresponding tothe three nonlinear modes, and ๐›ผ

    ๐‘–, ๐›ฝ๐‘–, and ๐›พ

    ๐‘–(๐‘– = 1, 2, . . . , 10)

    are the nonlinear coefficients.The linear viscous damping andexciting forces are assumed to be

    ๐œ‡๐‘›= ๐œ€๐œ‡๐‘›, ๐‘“๐‘›1= ๐œ€๐‘“๐‘›1, ๐‘“

    ๐‘›2= ๐œ€๐‘“๐‘›2,

    ๐‘“๐‘›3= ๐œ€๐‘“๐‘›3, ๐‘“๐‘›= ๐œ€2๐‘“๐‘›, ๐‘› = 1, 2, 3,

    (5)

    where ๐œ€ is a small perturbation parameter and 0 < ๐œ€ โ‰ช 1.The external excitation forces ๐‘“

    ๐‘›are of the order 2, and

    the linear viscous damping ๐œ‡๐‘›, parametric exciting forces๐‘“

    ๐‘›1,

    ๐‘“๐‘›2, and ๐‘“

    ๐‘›3are of the order 1.

    To consider the influence of the cubic terms on non-linear dynamic characteristics of the composite laminatedpiezoelectric rectangular plate, we need to obtain the second-order approximate solution of (4a), (4b), and (4c). Methodof multiple scales [29โ€“31] is applied to obtain a second-order approximation for the system. For the second-orderapproximation, we introduce three time scales defined by

    ๐‘‡0= ๐‘ก, ๐‘‡

    1= ๐œ€๐‘ก, ๐‘‡

    2= ๐œ€2๐‘ก. (6)

    In terms of these scales, the time derivatives become

    ๐‘‘

    ๐‘‘๐‘ก= ๐ท0+ ๐œ€๐ท1+ ๐œ€2๐ท2, (7a)

    ๐‘‘2

    ๐‘‘๐‘ก2= ๐ท2

    0+ 2๐œ€๐ท

    0๐ท1+ ๐œ€2(๐ท2

    1+ 2๐ท0๐ท2) , (7b)

    where ๐ท๐‘›= ๐œ•/๐œ•๐‘‡

    ๐‘›, ๐‘› = 0, 1, 2. We seek a uniform approxi-

    mation to the solution of (4a), (4b), and (4c) in the form:

    ๐‘ข๐‘› (๐‘ก, ๐œ€) = ๐œ€๐‘ข๐‘›1 (๐‘‡0, ๐‘‡1, ๐‘‡2) + ๐œ€

    2๐‘ข๐‘›2(๐‘‡0, ๐‘‡1, ๐‘‡2)

    + ๐œ€3๐‘ข๐‘›3(๐‘‡0, ๐‘‡1, ๐‘‡2) + ๐‘‚ (๐œ€

    4) , ๐‘› = 1, 2, 3.

    (8)

    Terms of ๐‘‚(๐œ€4) and higher orders are neglected. Substituting(5) and (7a)โ€“(8) into (4a), (4b), and (4c) and equating thecoefficients of like powers of ๐œ€, we obtain the following.

    Order ๐œ€

    (๐ท2

    0+ ๐œ”2

    1) ๐‘ข11= 0, (9a)

    (๐ท2

    0+ ๐œ”2

    2) ๐‘ข21= 0, (9b)

    (๐ท2

    0+ ๐œ”2

    3) ๐‘ข31= 0. (9c)

    Order ๐œ€2

    (๐ท2

    0+ ๐œ”2

    1) ๐‘ข12= โˆ’2๐ท

    0๐ท1๐‘ข11โˆ’ ๐œ‡1๐ท0๐‘ข11

    โˆ’ (๐‘“11cosฮฉ1๐‘‡0+ ๐‘“12cosฮฉ2๐‘‡0

    +๐‘“14cosฮฉ4๐‘‡0) ๐‘ข11+ ๐‘“1cosฮฉ3๐‘‡0,

    (10a)

    (๐ท2

    0+ ๐œ”2

    2) ๐‘ข22= โˆ’2๐ท

    0๐ท1๐‘ข21โˆ’ ๐œ‡2๐ท0๐‘ข21

    โˆ’ (๐‘“21cosฮฉ1๐‘‡0+ ๐‘“22cosฮฉ2๐‘‡0

    +๐‘“24cosฮฉ4๐‘‡0) ๐‘ข21+ ๐‘“2cosฮฉ3๐‘‡0,

    (10b)

    (๐ท2

    0+ ๐œ”2

    3) ๐‘ข32= โˆ’2๐ท

    0๐ท1๐‘ข31โˆ’ ๐œ‡3๐ท0๐‘ข31

    โˆ’ (๐‘“31cosฮฉ1๐‘‡0+ ๐‘“32cosฮฉ2๐‘‡0

    +๐‘“34cosฮฉ4๐‘‡0) ๐‘ข31+ ๐‘“3cosฮฉ3๐‘‡0.

    (10c)

    Order ๐œ€3

    (๐ท2

    0+ ๐œ”2

    1) ๐‘ข13= โˆ’๐ท2

    1๐‘ข11โˆ’ 2๐ท0๐ท2๐‘ข11โˆ’ 2๐ท0๐ท1๐‘ข12

    โˆ’ ๐œ‡1(๐ท0๐‘ข12+ ๐ท1๐‘ข11)

    โˆ’ (๐‘“11cosฮฉ1๐‘‡0+ ๐‘“12cosฮฉ2๐‘‡0

    + ๐‘“14cosฮฉ4๐‘‡0) ๐‘ข12

    โˆ’ ๐›ผ1๐‘ข2

    11๐‘ข21โˆ’ ๐›ผ2๐‘ข2

    11๐‘ข31โˆ’ ๐›ผ3๐‘ข2

    21๐‘ข11

    โˆ’ ๐›ผ4๐‘ข2

    21๐‘ข31โˆ’ ๐›ผ5๐‘ข2

    31๐‘ข11โˆ’ ๐›ผ6๐‘ข2

    31๐‘ข21

    โˆ’ ๐›ผ7๐‘ข3

    11โˆ’ ๐›ผ8๐‘ข3

    21โˆ’ ๐›ผ9๐‘ข3

    31โˆ’ ๐›ผ10๐‘ข11๐‘ข21๐‘ข31,

    (11a)

  • Mathematical Problems in Engineering 5

    (๐ท2

    0+ ๐œ”2

    2) ๐‘ข23= โˆ’๐ท2

    1๐‘ข21โˆ’ 2๐ท0๐ท2๐‘ข21โˆ’ 2๐ท0๐ท1๐‘ข22

    โˆ’ ๐œ‡2(๐ท0๐‘ข22+ ๐ท1๐‘ข21)

    โˆ’ (๐‘“21cosฮฉ1๐‘‡0+ ๐‘“22cosฮฉ2๐‘‡0

    +๐‘“24cosฮฉ4๐‘‡0) ๐‘ข22

    โˆ’ ๐›ฝ1๐‘ข2

    11๐‘ข21โˆ’ ๐›ฝ2๐‘ข2

    11๐‘ข31โˆ’ ๐›ฝ3๐‘ข2

    21๐‘ข11

    โˆ’ ๐›ฝ4๐‘ข2

    21๐‘ข31โˆ’ ๐›ฝ5๐‘ข2

    31๐‘ข11โˆ’ ๐›ฝ6๐‘ข2

    31๐‘ข21

    โˆ’ ๐›ฝ7๐‘ข3

    11โˆ’ ๐›ฝ8๐‘ข3

    21โˆ’ ๐›ฝ9๐‘ข3

    31โˆ’ ๐›ฝ10๐‘ข11๐‘ข21๐‘ข31,

    (11b)

    (๐ท2

    0+ ๐œ”2

    3) ๐‘ข33= โˆ’๐ท2

    1๐‘ข31โˆ’ 2๐ท0๐ท2๐‘ข31โˆ’ 2๐ท0๐ท1๐‘ข32

    โˆ’ ๐œ‡3(๐ท0๐‘ข32+ ๐ท1๐‘ข31)

    โˆ’ (๐‘“31cosฮฉ1๐‘‡0+ ๐‘“32cosฮฉ2๐‘‡0

    +๐‘“34cosฮฉ4๐‘‡0) ๐‘ข32

    โˆ’ ๐›พ1๐‘ข2

    11๐‘ข21โˆ’ ๐›พ2๐‘ข2

    11๐‘ข31โˆ’ ๐›พ3๐‘ข2

    21๐‘ข11

    โˆ’ ๐›พ4๐‘ข2

    21๐‘ข31โˆ’ ๐›พ5๐‘ข2

    31๐‘ข11โˆ’ ๐›พ6๐‘ข2

    31๐‘ข21

    โˆ’ ๐›พ7๐‘ข3

    11โˆ’ ๐›พ8๐‘ข3

    21โˆ’ ๐›พ9๐‘ข3

    31โˆ’ ๐›พ10๐‘ข11๐‘ข21๐‘ข31.

    (11c)

    The general solutions of (9a), (9b), and (9c) can be written inthe form

    ๐‘ข11= ๐ด1(๐‘‡1, ๐‘‡2) exp (๐‘–๐œ”

    1๐‘‡0) + ๐‘๐‘, (12a)

    ๐‘ข21= ๐ด2(๐‘‡1, ๐‘‡2) exp (๐‘–๐œ”

    2๐‘‡0) + ๐‘๐‘, (12b)

    ๐‘ข31= ๐ด3(๐‘‡1, ๐‘‡2) exp (๐‘–๐œ”

    3๐‘‡0) + ๐‘๐‘, (12c)

    where๐ด1,๐ด2, and๐ด

    3are a complex function in๐‘‡

    1, ๐‘‡2which

    can be determined from eliminating the secular terms at thenext approximation and ๐‘๐‘ stands for the complex conjugateof the preceding terms. Substituting (12a), (12b), and (12c)into (10a), (10b), and (10c) and eliminating the secular terms,then the first-order approximations are given by

    ๐‘ข12= ๐ธ1exp (๐‘–๐œ”

    1๐‘‡0) + ๐ธ2exp (๐‘– (ฮฉ

    1+ ๐œ”1) ๐‘‡0)

    + ๐ธ3exp (๐‘– (ฮฉ

    1โˆ’ ๐œ”1) ๐‘‡0) + ๐ธ4exp (๐‘– (ฮฉ

    2+ ๐œ”1) ๐‘‡0)

    + ๐ธ5exp (๐‘– (ฮฉ

    2โˆ’ ๐œ”1) ๐‘‡0) + ๐ธ6exp (๐‘– (ฮฉ

    4+ ๐œ”1) ๐‘‡0)

    + ๐ธ7exp (๐‘– (ฮฉ

    4โˆ’ ๐œ”1) ๐‘‡0) + ๐‘๐‘,

    (13a)

    ๐‘ข22= ๐ธ8exp (๐‘–๐œ”

    2๐‘‡0) + ๐ธ9exp (๐‘– (ฮฉ

    1+ ๐œ”2) ๐‘‡0)

    + ๐ธ10exp (๐‘– (ฮฉ

    1โˆ’ ๐œ”2) ๐‘‡0) + ๐ธ11exp (๐‘– (ฮฉ

    2+ ๐œ”2) ๐‘‡0)

    + ๐ธ12exp (๐‘– (ฮฉ

    2โˆ’ ๐œ”2) ๐‘‡0) + ๐ธ13exp (๐‘– (ฮฉ

    4+ ๐œ”2) ๐‘‡0)

    + ๐ธ14exp (๐‘– (ฮฉ

    4โˆ’ ๐œ”2) ๐‘‡0) + ๐‘๐‘,

    (13b)

    ๐‘ข32= ๐ธ15exp (๐‘–๐œ”

    3๐‘‡0) + ๐ธ16exp (๐‘– (ฮฉ

    1+ ๐œ”3) ๐‘‡0)

    + ๐ธ17exp (๐‘– (ฮฉ

    1โˆ’ ๐œ”3) ๐‘‡0) + ๐ธ18exp (๐‘– (ฮฉ

    2+ ๐œ”3) ๐‘‡0)

    + ๐ธ19exp (๐‘– (ฮฉ

    2โˆ’ ๐œ”3) ๐‘‡0) + ๐ธ20exp (๐‘– (ฮฉ

    4+ ๐œ”3) ๐‘‡0)

    + ๐ธ21exp (๐‘– (ฮฉ

    4โˆ’ ๐œ”3) ๐‘‡0) + ๐ธ22exp (๐‘–ฮฉ

    3๐‘‡0) + ๐‘๐‘,

    (13c)

    where ๐ธ๐‘–(๐‘– = 1, 2, . . . , 22) are the complex functions in ๐‘‡

    1

    and ๐‘‡2. From (12a)โ€“(13c) into (11a), (11b), and (11c) and elim-

    inating the secular terms, the second-order approximation isgiven by

    ๐‘ข13(๐‘‡0, ๐‘‡1, ๐‘‡2) = ๐ป

    1exp (๐‘–๐œ”

    2๐‘‡0) + ๐ป2exp (๐‘–๐œ”

    3๐‘‡0)

    + ๐ป3exp (3๐‘–๐œ”

    1๐‘‡0) + ๐ป4exp (3๐‘–๐œ”

    2๐‘‡0)

    + ๐ป5exp (3๐‘–๐œ”

    3๐‘‡0)

    + ๐ป6exp (๐‘– (๐œ”

    2ยฑ 2๐œ”1) ๐‘‡0)

    + ๐ป7exp (๐‘– (๐œ”

    3ยฑ 2๐œ”1) ๐‘‡0)

    + ๐ป8exp (๐‘– (2๐œ”

    2ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป9exp (๐‘– (2๐œ”

    3ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป10exp (๐‘– (๐œ”

    2ยฑ 2๐œ”3) ๐‘‡0)

    + ๐ป11exp (๐‘– (๐œ”

    3ยฑ 2๐œ”2) ๐‘‡0)

    + ๐ป12exp (๐‘– (๐œ”

    3ยฑ ๐œ”2ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป13exp (๐‘–ฮฉ

    3๐‘‡0)

    + ๐ป14exp (๐‘– (ฮฉ

    3ยฑ ฮฉ1) ๐‘‡0)

    + ๐ป15exp (๐‘– (ฮฉ

    3ยฑ ฮฉ2) ๐‘‡0)

    + ๐ป16exp (๐‘– (ฮฉ

    3ยฑ ฮฉ4) ๐‘‡0)

    + ๐ป17exp (๐‘– (ฮฉ

    1ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป18exp (๐‘– (ฮฉ

    2ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป19exp (๐‘– (ฮฉ

    4ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป20exp (๐‘– (2ฮฉ

    1ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป21exp (๐‘– (2ฮฉ

    2ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป22exp (๐‘– (2ฮฉ

    4ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป23exp (๐‘– (ฮฉ

    2ยฑ ฮฉ1ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป24exp (๐‘– (ฮฉ

    4ยฑ ฮฉ1ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป25exp (๐‘– (ฮฉ

    4ยฑ ฮฉ2ยฑ ๐œ”1) ๐‘‡0) + ๐‘๐‘,

    (14a)๐‘ข23(๐‘‡0, ๐‘‡1, ๐‘‡2) = ๐ป

    26exp (๐‘–๐œ”

    1๐‘‡0) + ๐ป27exp (๐‘–๐œ”

    3๐‘‡0)

    + ๐ป28exp (3๐‘–๐œ”

    1๐‘‡0) + ๐ป29exp (3๐‘–๐œ”

    2๐‘‡0)

  • 6 Mathematical Problems in Engineering

    + ๐ป30exp (3๐‘–๐œ”

    3๐‘‡0)

    + ๐ป31exp (๐‘– (๐œ”

    2ยฑ 2๐œ”1) ๐‘‡0)

    + ๐ป32exp (๐‘– (2๐œ”

    2ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป33exp (๐‘– (๐œ”

    3ยฑ 2๐œ”1) ๐‘‡0)

    + ๐ป34exp (๐‘– (2๐œ”

    3ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป35exp (๐‘– (๐œ”

    2ยฑ 2๐œ”3) ๐‘‡0)

    + ๐ป36exp (๐‘– (2๐œ”

    2ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป37exp (๐‘– (๐œ”

    3ยฑ ๐œ”2ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป38exp (๐‘–ฮฉ

    3๐‘‡0)

    + ๐ป39exp (๐‘– (ฮฉ

    3ยฑ ฮฉ1) ๐‘‡0)

    + ๐ป40exp (๐‘– (ฮฉ

    3ยฑ ฮฉ2) ๐‘‡0)

    + ๐ป41exp (๐‘– (ฮฉ

    4ยฑ ฮฉ3) ๐‘‡0)

    + ๐ป42exp (๐‘– (ฮฉ

    1ยฑ ๐œ”2) ๐‘‡0)

    + ๐ป43exp (๐‘– (ฮฉ

    2ยฑ ๐œ”2) ๐‘‡0)

    + ๐ป44exp (๐‘– (ฮฉ

    4ยฑ ๐œ”2) ๐‘‡0)

    + ๐ป45exp (๐‘– (2ฮฉ

    1ยฑ ๐œ”2) ๐‘‡0)

    + ๐ป46exp (๐‘– (2ฮฉ

    2ยฑ ๐œ”2) ๐‘‡0)

    + ๐ป47exp (๐‘– (2ฮฉ

    4ยฑ ๐œ”2) ๐‘‡0)

    + ๐ป48exp (๐‘– (ฮฉ

    2ยฑ ฮฉ1ยฑ ๐œ”2) ๐‘‡0)

    + ๐ป49exp (๐‘– (ฮฉ

    4ยฑ ฮฉ1ยฑ ๐œ”2) ๐‘‡0)

    + ๐ป50exp (๐‘– (ฮฉ

    4ยฑ ฮฉ2ยฑ ๐œ”2) ๐‘‡0) + ๐‘๐‘,

    (14b)๐‘ข33(๐‘‡0, ๐‘‡1, ๐‘‡2) = ๐ป

    51exp (3๐‘–๐œ”

    3๐‘‡0) + ๐ป52exp (๐‘–๐œ”

    1๐‘‡0)

    + ๐ป53exp (3๐‘–๐œ”

    1๐‘‡0) + ๐ป54exp (๐‘–๐œ”

    2๐‘‡0)

    + ๐ป55exp (3๐‘–๐œ”

    2๐‘‡0)

    + ๐ป56exp (๐‘– (๐œ”

    2ยฑ 2๐œ”1) ๐‘‡0)

    + ๐ป57exp (๐‘– (2๐œ”

    2ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป58exp (๐‘– (๐œ”

    3ยฑ 2๐œ”1) ๐‘‡0)

    + ๐ป59exp (๐‘– (2๐œ”

    3ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป60exp (๐‘– (๐œ”

    2ยฑ 2๐œ”3) ๐‘‡0)

    + ๐ป61exp (๐‘– (2๐œ”

    2ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป62exp (๐‘– (๐œ”

    3ยฑ ๐œ”2ยฑ ๐œ”1) ๐‘‡0)

    + ๐ป63exp (๐‘–ฮฉ

    3๐‘‡0)

    + ๐ป64exp (๐‘– (ฮฉ

    3ยฑ ฮฉ1) ๐‘‡0)

    + ๐ป65exp (๐‘– (ฮฉ

    3ยฑ ฮฉ2) ๐‘‡0)

    + ๐ป66exp (๐‘– (ฮฉ

    3ยฑ ฮฉ4) ๐‘‡0)

    + ๐ป67exp (๐‘– (ฮฉ

    1ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป68exp (๐‘– (ฮฉ

    2ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป69exp (๐‘– (ฮฉ

    4ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป70exp (๐‘– (2ฮฉ

    1ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป71exp (๐‘– (2ฮฉ

    2ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป72exp (๐‘– (2ฮฉ

    4ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป73exp (๐‘– (ฮฉ

    2ยฑ ฮฉ1ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป74exp (๐‘– (ฮฉ

    4ยฑ ฮฉ1ยฑ ๐œ”3) ๐‘‡0)

    + ๐ป75exp (๐‘– (ฮฉ

    4ยฑ ฮฉ2ยฑ ๐œ”3) ๐‘‡0) + ๐‘๐‘,

    (14c)

    where ๐ป๐‘–(๐‘– = 1, 2, . . . , 75) are the complex functions in ๐‘‡

    1

    and ๐‘‡2. From the above derived solutions, the reported

    resonance cases are the following.

    (i) Primary resonance:ฮฉ1โ‰… ๐œ”๐‘›,ฮฉ2โ‰… ๐œ”๐‘›,ฮฉ3โ‰… ๐œ”๐‘›,ฮฉ4โ‰…

    ๐œ”๐‘›, and ๐‘› = 1, 2, 3.

    (ii) Subharmonic resonance: ฮฉ1โ‰… 2๐œ”๐‘›, ฮฉ2โ‰… 2๐œ”๐‘›, ฮฉ4โ‰…

    2๐œ”๐‘›, and ๐‘› = 1, 2, 3.

    (iii) Internal or secondary resonance: ๐œ”1โ‰… ๐œ”2, ๐œ”2โ‰… ๐œ”3,

    ๐œ”3โ‰… ๐œ”1, ๐œ”1โ‰… 3๐œ”๐‘ , ๐œ”2โ‰… 3๐œ”๐‘Ÿ, ๐œ”3โ‰… 3๐œ”๐‘š, ๐‘  = 2, 3,

    ๐‘Ÿ = 1, 3, and๐‘š = 1, 2.(iv) Combined resonance: ๐œ”

    3ยฑ ๐œ”2โ‰… 2๐œ”1, ๐œ”3ยฑ ๐œ”1โ‰… 2๐œ”2,

    ๐œ”1ยฑ๐œ”2โ‰… 2๐œ”3,๐œ”2ยฑ2๐œ”3โ‰… ๐œ”1,๐œ”3ยฑ2๐œ”2โ‰… ๐œ”1,๐œ”3ยฑ2๐œ”1โ‰…

    ๐œ”2, ๐œ”1ยฑ 2๐œ”3โ‰… ๐œ”2, ๐œ”2ยฑ 2๐œ”1โ‰… ๐œ”3, ๐œ”1ยฑ 2๐œ”2โ‰… ๐œ”3,

    ฮฉ3ยฑ ฮฉ๐‘กโ‰… ๐œ”๐‘›, ฮฉ4ยฑ ฮฉ๐‘šโ‰… 2๐œ”๐‘›, ฮฉ2ยฑ ฮฉ1โ‰… 2๐œ”๐‘›,

    ๐‘ก = 1, 2, 4, ๐‘š = 1, 2, and ๐‘› = 1, 2, 3.(v) Simultaneous or incident resonance.

    Any combination of the previous resonance cases is con-sidered as simultaneous resonance.

    3. Stability Analysis

    Thebehavior of such a system can be very complex, especiallywhen the natural frequencies and the forcing frequency sat-isfy certain internal and external resonance conditions. Thestudy is focused on the case of 1 : 1 : 3 primary resonance andinternal resonance, where ฮฉ

    3โ‰… ๐œ”1, ๐œ”2โ‰… ๐œ”1, and ๐œ”

    3โ‰… 3๐œ”1.

    To describe how close the frequencies are to the resonanceconditions, we introduce detuning parameters as follows:

    ฮฉ3= ๐œ”1+ ๐œŽ1= ๐œ”1+ ๐œ€๏ฟฝฬ‚๏ฟฝ1,

    ๐œ”2= ๐œ”1+ ๐œŽ2= ๐œ”1+ ๐œ€๏ฟฝฬ‚๏ฟฝ2,

    ๐œ”3= 3๐œ”1+ ๐œŽ3= 3๐œ”1+ ๐œ€๏ฟฝฬ‚๏ฟฝ3,

    (15)

  • Mathematical Problems in Engineering 7

    where๐œŽ1and๐œŽ2,๐œŽ3are called the external and internal detun-

    ing parameters, respectively. Eliminating the secular termsleads to solvability conditions for the first- and second-orderexpansions as follows:

    2๐‘–๐œ”1๐ท1๐ด1= โˆ’๐‘–๐œ‡

    1๐œ”1๐ด1+๐‘“1

    2exp (๐‘–๏ฟฝฬ‚๏ฟฝ

    1๐‘‡1) , (16a)

    2๐‘–๐œ”2๐ท1๐ด2= โˆ’๐‘–๐œ‡

    2๐œ”2๐ด2+๐‘“2

    2exp (๐‘– (๏ฟฝฬ‚๏ฟฝ

    1โˆ’ ๏ฟฝฬ‚๏ฟฝ2) ๐‘‡1) , (16b)

    2๐‘–๐œ”3๐ท1๐ด3= โˆ’๐‘–๐œ‡

    3๐œ”3๐ด3, (16c)

    2๐‘–๐œ”1๐ท2๐ด1

    = โˆ’๐ท2

    1๐ด1โˆ’ ๐œ‡1๐ท1๐ด1

    โˆ’ {๐‘“2

    11

    2 (ฮฉ2

    1โˆ’ 4๐œ”2

    1)+

    ๐‘“2

    12

    2 (ฮฉ2

    2โˆ’ 4๐œ”2

    1)+

    ๐‘“2

    14

    2 (ฮฉ2

    4โˆ’ 4๐œ”2

    1)}๐ด1

    โˆ’ {2๐›ผ1๐ด1๐ด1+ 2๐›ผ6๐ด3๐ด3+ 3๐›ผ8๐ด2๐ด2}๐ด2exp (๐‘–๏ฟฝฬ‚๏ฟฝ

    2๐‘‡1)

    โˆ’ ๐›ผ1๐ด2

    1๐ด2exp (โˆ’๐‘–๏ฟฝฬ‚๏ฟฝ

    2๐‘‡1) โˆ’ ๐›ผ2๐ด2

    1๐ด3exp (๐‘–๏ฟฝฬ‚๏ฟฝ

    3๐‘‡1)

    โˆ’ {2๐›ผ3๐ด2๐ด2+ 2๐›ผ5๐ด3๐ด3+ 3๐›ผ7๐ด1๐ด1}๐ด1

    โˆ’ ๐›ผ4๐ด2

    2๐ด3exp (๐‘– (๏ฟฝฬ‚๏ฟฝ

    3โˆ’ 2๏ฟฝฬ‚๏ฟฝ2) ๐‘‡1)

    โˆ’ ๐›ผ10๐ด1๐ด2๐ด3exp (๐‘– (๏ฟฝฬ‚๏ฟฝ

    3โˆ’ ๏ฟฝฬ‚๏ฟฝ2) ๐‘‡1) ,

    (17a)2๐‘–๐œ”2๐ท2๐ด2

    = โˆ’๐ท2

    1๐ด2โˆ’ ๐œ‡2๐ท1๐ด2

    โˆ’ {๐‘“2

    21

    2 (ฮฉ2

    1โˆ’ 4๐œ”2

    2)+

    ๐‘“2

    22

    2 (ฮฉ2

    2โˆ’ 4๐œ”2

    2)+

    ๐‘“2

    24

    2 (ฮฉ2

    4โˆ’ 4๐œ”2

    2)}๐ด2

    โˆ’ {2๐›ฝ3๐ด2๐ด2+ 2๐›ฝ5๐ด3๐ด3+ 3๐›ฝ7๐ด1๐ด1}

    ร— ๐ด1exp (โˆ’๐‘–๏ฟฝฬ‚๏ฟฝ

    2๐‘‡1)

    โˆ’ ๐›ฝ3๐ด2

    2๐ด1exp (๐‘–๏ฟฝฬ‚๏ฟฝ

    2๐‘‡1) โˆ’ ๐›ฝ1๐ด2

    1๐ด2exp (โˆ’2๐‘–๏ฟฝฬ‚๏ฟฝ

    2๐‘‡1)

    โˆ’ {2๐›ฝ6๐ด3๐ด3+ 2๐›ฝ1๐ด1๐ด1+ 3๐›ฝ8๐ด2๐ด2}๐ด2

    โˆ’ ๐›ฝ2๐ด2

    1๐ด3exp (๐‘– (๏ฟฝฬ‚๏ฟฝ

    3โˆ’ ๏ฟฝฬ‚๏ฟฝ2) ๐‘‡1)

    โˆ’ ๐›ฝ10๐ด1๐ด2๐ด3exp (๐‘– (๏ฟฝฬ‚๏ฟฝ

    3โˆ’ 2๏ฟฝฬ‚๏ฟฝ2) ๐‘‡1)

    โˆ’ ๐›ฝ4๐ด2

    2๐ด3exp (๐‘– (๏ฟฝฬ‚๏ฟฝ

    3โˆ’ 3๏ฟฝฬ‚๏ฟฝ2) ๐‘‡1) ,

    (17b)2๐‘–๐œ”3๐ท2๐ด3

    = โˆ’๐ท2

    1๐ด3โˆ’ ๐œ‡3๐ท1๐ด3

    โˆ’ {๐‘“2

    31

    2 (ฮฉ2

    1โˆ’ 4๐œ”2

    3)+

    ๐‘“2

    32

    2 (ฮฉ2

    2โˆ’ 4๐œ”2

    3)+

    ๐‘“2

    34

    2 (ฮฉ2

    4โˆ’ 4๐œ”2

    3)}๐ด3

    โˆ’ ๐›พ10๐ด1๐ด2๐ด3exp (โˆ’๐‘–๏ฟฝฬ‚๏ฟฝ

    2๐‘‡1)

    โˆ’ ๐›พ10๐ด1๐ด2๐ด3exp (๐‘–๏ฟฝฬ‚๏ฟฝ

    2๐‘‡1)

    โˆ’ ๐›พ7๐ด3

    1exp (โˆ’๐‘–๏ฟฝฬ‚๏ฟฝ

    3๐‘‡1)

    โˆ’ {2๐›พ2๐ด1๐ด1+ 2๐›พ4๐ด2๐ด2+ 3๐›พ9๐ด3๐ด3}๐ด3

    โˆ’ ๐›พ1๐ด2

    1๐ด2exp (๐‘– (๏ฟฝฬ‚๏ฟฝ

    2โˆ’ ๏ฟฝฬ‚๏ฟฝ3) ๐‘‡1)

    โˆ’ ๐›พ3๐ด2

    2๐ด1exp (๐‘– (2๏ฟฝฬ‚๏ฟฝ

    2โˆ’ ๏ฟฝฬ‚๏ฟฝ3) ๐‘‡1)

    โˆ’ ๐›พ8๐ด3

    2exp (๐‘– (3๏ฟฝฬ‚๏ฟฝ

    2โˆ’ ๏ฟฝฬ‚๏ฟฝ3) ๐‘‡1) .

    (17c)

    From (7a), multiplying both sides by 2๐‘–๐œ”๐‘›, we get

    2๐‘–๐œ”๐‘›

    ๐‘‘๐ด๐‘›

    ๐‘‘๐‘ก= ๐œ€2๐‘–๐œ”

    ๐‘›๐ท1๐ด๐‘›+ ๐œ€22๐‘–๐œ”๐‘›๐ท2๐ด๐‘›,

    ๐‘› = 1, 2, 3.

    (18)

    To analyze the solutions of (16a)โ€“(17c), we express ๐ด๐‘›in the

    polar form as follows:

    ๐ด๐‘›(๐‘‡1, ๐‘‡2) =

    ๐‘Ž๐‘›

    2exp (๐‘–๐œ‘

    ๐‘›) ,

    ๐‘Ž๐‘›= ๐œ€๐‘Ž๐‘›, (๐‘› = 1, 2, 3) ,

    (19)

    where ๐‘Ž๐‘›and ๐œ‘

    ๐‘›are the steady-state amplitudes and phases

    of the motion, respectively. Substituting (16a)โ€“(17c) and (19)into (18) and equating the real and imaginary parts, we obtainthe following equations describing the modulation of theamplitudes and phases of the response:

    ฬ‡๐‘Ž1= โˆ’

    ๐œ‡1

    2๐‘Ž1+ {

    ๐‘“1

    2๐œ”1

    โˆ’๐œŽ1๐‘“1

    4๐œ”2

    1

    } sin ๐œƒ1

    +๐œ‡1๐‘“1

    8๐œ”2

    1

    cos ๐œƒ1โˆ’๐›ผ1

    8๐œ”1

    ๐‘Ž2

    1๐‘Ž2sin ๐œƒ2

    โˆ’๐›ผ2

    8๐œ”1

    ๐‘Ž2

    1๐‘Ž3sin ๐œƒ3โˆ’๐›ผ4

    8๐œ”1

    ๐‘Ž2

    2๐‘Ž3sin (๐œƒ3โˆ’ 2๐œƒ2)

    โˆ’๐›ผ6

    4๐œ”1

    ๐‘Ž2

    3๐‘Ž2sin ๐œƒ2โˆ’3๐›ผ8

    8๐œ”1

    ๐‘Ž3

    2sin ๐œƒ2

    โˆ’๐›ผ10

    8๐œ”1

    ๐‘Ž1๐‘Ž2๐‘Ž3sin (๐œƒ3โˆ’ ๐œƒ2) ,

    ๐‘Ž1๏ฟฝฬ‡๏ฟฝ1= {โˆ’

    ๐œ‡2

    1

    8๐œ”1

    +ฮ“1

    2๐œ”1

    }๐‘Ž1โˆ’ {

    ๐‘“1

    2๐œ”1

    โˆ’๐œŽ1๐‘“1

    4๐œ”2

    1

    } cos ๐œƒ1

    +๐œ‡1๐‘“1

    8๐œ”2

    1

    sin ๐œƒ1+3๐›ผ1

    8๐œ”1

    ๐‘Ž2

    1๐‘Ž2cos ๐œƒ2+๐›ผ2

    8๐œ”1

    ๐‘Ž2

    1๐‘Ž3cos ๐œƒ3

    +๐›ผ3

    4๐œ”1

    ๐‘Ž1๐‘Ž2

    2+๐›ผ4

    8๐œ”1

    ๐‘Ž2

    2๐‘Ž3cos (๐œƒ

    3โˆ’ 2๐œƒ2)

    +๐›ผ5

    4๐œ”1

    ๐‘Ž1๐‘Ž2

    3+๐›ผ6

    4๐œ”1

    ๐‘Ž2

    3๐‘Ž2cos ๐œƒ2+3๐›ผ7

    8๐œ”1

    ๐‘Ž3

    1

  • 8 Mathematical Problems in Engineering

    +3๐›ผ8

    8๐œ”1

    ๐‘Ž3

    2cos ๐œƒ2+๐›ผ10

    8๐œ”1

    ๐‘Ž1๐‘Ž2๐‘Ž3cos (๐œƒ

    3โˆ’ ๐œƒ2) ,

    ฬ‡๐‘Ž2= โˆ’

    ๐œ‡2

    2๐‘Ž2+ {

    ๐‘“2

    2๐œ”2

    โˆ’(๐œŽ1โˆ’ ๐œŽ2) ๐‘“2

    4๐œ”2

    2

    } sin (๐œƒ1โˆ’ ๐œƒ2)

    +๐œ‡2๐‘“2

    8๐œ”2

    2

    cos (๐œƒ1โˆ’ ๐œƒ2) +

    ๐›ฝ1

    8๐œ”2

    ๐‘Ž2

    1๐‘Ž2sin 2๐œƒ

    2

    โˆ’๐›ฝ2

    8๐œ”2

    ๐‘Ž2

    1๐‘Ž3sin (๐œƒ3โˆ’ ๐œƒ2) +

    ๐›ฝ3

    8๐œ”2

    ๐‘Ž2

    2๐‘Ž1sin ๐œƒ2

    โˆ’๐›ฝ4

    8๐œ”2

    ๐‘Ž2

    2๐‘Ž3sin (๐œƒ3โˆ’ 3๐œƒ2) +

    ๐›ฝ5

    4๐œ”2

    ๐‘Ž2

    3๐‘Ž1sin ๐œƒ2

    +3๐›ฝ7

    8๐œ”2

    ๐‘Ž3

    1sin ๐œƒ2โˆ’๐›ฝ10

    8๐œ”2

    ๐‘Ž1๐‘Ž2๐‘Ž3sin (๐œƒ3โˆ’ 2๐œƒ2) ,

    ๐‘Ž2๏ฟฝฬ‡๏ฟฝ2= {โˆ’

    ๐œ‡2

    2

    8๐œ”2

    +ฮ“2

    2๐œ”2

    }๐‘Ž2

    + {(๐œŽ1โˆ’ ๐œŽ2) ๐‘“2

    4๐œ”2

    2

    โˆ’๐‘“2

    2๐œ”2

    } cos (๐œƒ1โˆ’ ๐œƒ2)

    +๐œ‡2๐‘“2

    8๐œ”2

    2

    sin (๐œƒ1โˆ’ ๐œƒ2) +

    ๐›ฝ1

    8๐œ”2

    ๐‘Ž2

    1๐‘Ž2cos 2๐œƒ

    2

    +๐›ฝ1

    4๐œ”2

    ๐‘Ž2

    1๐‘Ž2+๐›ฝ2

    8๐œ”2

    ๐‘Ž2

    1๐‘Ž3cos (๐œƒ

    3โˆ’ ๐œƒ2)

    +3๐›ฝ3

    8๐œ”2

    ๐‘Ž2

    2๐‘Ž1cos ๐œƒ2+๐›ฝ4

    8๐œ”2

    ๐‘Ž2

    2๐‘Ž3cos (๐œƒ

    3โˆ’ 3๐œƒ2)

    +๐›ฝ5

    4๐œ”2

    ๐‘Ž2

    3๐‘Ž1cos ๐œƒ2+๐›ฝ6

    4๐œ”2

    ๐‘Ž2

    3๐‘Ž2+3๐›ฝ7

    8๐œ”2

    ๐‘Ž3

    1cos ๐œƒ2

    +3๐›ฝ8

    8๐œ”2

    ๐‘Ž3

    2+๐›ฝ10

    8๐œ”2

    ๐‘Ž1๐‘Ž2๐‘Ž3cos (๐œƒ

    3โˆ’ 2๐œƒ2) ,

    ฬ‡๐‘Ž3= โˆ’

    ๐œ‡3

    2๐‘Ž3โˆ’๐›พ1

    8๐œ”3

    ๐‘Ž2

    1๐‘Ž2sin (๐œƒ2โˆ’ ๐œƒ3)

    โˆ’๐›พ3

    8๐œ”3

    ๐‘Ž2

    2๐‘Ž1sin (2๐œƒ

    2โˆ’ ๐œƒ3) +

    ๐›พ7

    8๐œ”3

    ๐‘Ž3

    1sin ๐œƒ3

    โˆ’๐›พ8

    8๐œ”3

    ๐‘Ž3

    2sin (3๐œƒ

    2โˆ’ ๐œƒ3) ,

    ๐‘Ž3๏ฟฝฬ‡๏ฟฝ3= {โˆ’

    ๐œ‡2

    3

    8๐œ”3

    +ฮ“3

    2๐œ”3

    }๐‘Ž3+๐›พ1

    8๐œ”3

    ๐‘Ž2

    1๐‘Ž2cos (๐œƒ

    2โˆ’ ๐œƒ3)

    +๐›พ2

    4๐œ”3

    ๐‘Ž2

    1๐‘Ž3+๐›พ3

    8๐œ”3

    ๐‘Ž2

    2๐‘Ž1cos (2๐œƒ

    2โˆ’ ๐œƒ3)

    +๐›พ4

    4๐œ”3

    ๐‘Ž2

    2๐‘Ž3+๐›พ7

    8๐œ”3

    ๐‘Ž3

    1cos ๐œƒ3

    +๐›พ8

    8๐œ”3

    ๐‘Ž3

    2cos (3๐œƒ

    2โˆ’ ๐œƒ3) +

    3๐›พ9

    8๐œ”3

    ๐‘Ž3

    3

    +๐›พ10

    4๐œ”3

    ๐‘Ž1๐‘Ž2๐‘Ž3cos ๐œƒ2,

    (20)

    where

    ฮ“๐‘›= {

    ๐‘“2

    ๐‘›1

    2 (ฮฉ2

    1โˆ’ 4๐œ”2๐‘›)+

    ๐‘“2

    ๐‘›2

    2 (ฮฉ2

    2โˆ’ 4๐œ”2๐‘›)+

    ๐‘“2

    ๐‘›4

    2 (ฮฉ2

    4โˆ’ 4๐œ”2๐‘›)} ,

    ๐‘› = 1, 2, 3,

    ๐œƒ1= ๏ฟฝฬ‚๏ฟฝ1๐‘‡1โˆ’ ๐œ‘1,

    ๐œƒ2= ๏ฟฝฬ‚๏ฟฝ2๐‘‡1+ ๐œ‘2โˆ’ ๐œ‘1,

    ๐œƒ3= ๏ฟฝฬ‚๏ฟฝ3๐‘‡1+ ๐œ‘3โˆ’ 3๐œ‘1.

    (21)

    Steady-state solutions of the system correspond to the fixedpoints of (20), which in turn correspond to

    ๏ฟฝฬ‡๏ฟฝ1= ๐œŽ1,

    ๏ฟฝฬ‡๏ฟฝ2= ๐œŽ1โˆ’ ๐œŽ2,

    ๏ฟฝฬ‡๏ฟฝ3= 3๐œŽ1โˆ’ ๐œŽ3.

    (22)

    Hence, the fixed points of (20) are given by

    โˆ’๐œ‡1

    2๐‘Ž1+ {

    ๐‘“1

    2๐œ”1

    โˆ’๐œŽ1๐‘“1

    4๐œ”2

    1

    } sin ๐œƒ1

    +๐œ‡1๐‘“1

    8๐œ”2

    1

    cos ๐œƒ1โˆ’๐›ผ1

    8๐œ”1

    ๐‘Ž2

    1๐‘Ž2sin ๐œƒ2

    โˆ’๐›ผ2

    8๐œ”1

    ๐‘Ž2

    1๐‘Ž3sin ๐œƒ3โˆ’๐›ผ4

    8๐œ”1

    ๐‘Ž2

    2๐‘Ž3sin (๐œƒ3โˆ’ 2๐œƒ2)

    โˆ’๐›ผ6

    4๐œ”1

    ๐‘Ž2

    3๐‘Ž2sin ๐œƒ2โˆ’3๐›ผ8

    8๐œ”1

    ๐‘Ž3

    2sin ๐œƒ2

    โˆ’๐›ผ10

    8๐œ”1

    ๐‘Ž1๐‘Ž2๐‘Ž3sin (๐œƒ3โˆ’ ๐œƒ2) = 0,

    ๐‘Ž1๐œŽ1+ {

    ๐œ‡2

    1

    8๐œ”1

    โˆ’ฮ“1

    2๐œ”1

    }๐‘Ž1

    + {๐‘“1

    2๐œ”1

    โˆ’๐œŽ1๐‘“1

    4๐œ”2

    1

    } cos ๐œƒ1โˆ’๐œ‡1๐‘“1

    8๐œ”2

    1

    sin ๐œƒ1

    โˆ’3๐›ผ1

    8๐œ”1

    ๐‘Ž2

    1๐‘Ž2cos ๐œƒ2โˆ’๐›ผ2

    8๐œ”1

    ๐‘Ž2

    1๐‘Ž3cos ๐œƒ3

    โˆ’๐›ผ3

    4๐œ”1

    ๐‘Ž1๐‘Ž2

    2โˆ’๐›ผ4

    8๐œ”1

    ๐‘Ž2

    2๐‘Ž3cos (๐œƒ

    3โˆ’ 2๐œƒ2) โˆ’

    ๐›ผ5

    4๐œ”1

    ๐‘Ž1๐‘Ž2

    3

    โˆ’๐›ผ6

    4๐œ”1

    ๐‘Ž2

    3๐‘Ž2cos ๐œƒ2โˆ’3๐›ผ7

    8๐œ”1

    ๐‘Ž3

    1โˆ’3๐›ผ8

    8๐œ”1

    ๐‘Ž3

    2cos ๐œƒ2

    โˆ’๐›ผ10

    8๐œ”1

    ๐‘Ž1๐‘Ž2๐‘Ž3cos (๐œƒ

    3โˆ’ ๐œƒ2) = 0,

    โˆ’๐œ‡2

    2๐‘Ž2+ {

    ๐‘“2

    2๐œ”2

    โˆ’(๐œŽ1โˆ’ ๐œŽ2) ๐‘“2

    4๐œ”2

    2

    } sin (๐œƒ1โˆ’ ๐œƒ2)

    +๐œ‡2๐‘“2

    8๐œ”2

    2

    cos (๐œƒ1โˆ’ ๐œƒ2)

    +๐›ฝ1

    8๐œ”2

    ๐‘Ž2

    1๐‘Ž2sin 2๐œƒ

    2โˆ’๐›ฝ2

    8๐œ”2

    ๐‘Ž2

    1๐‘Ž3sin (๐œƒ3โˆ’ ๐œƒ2)

  • Mathematical Problems in Engineering 9

    +๐›ฝ3

    8๐œ”2

    ๐‘Ž2

    2๐‘Ž1sin ๐œƒ2โˆ’๐›ฝ4

    8๐œ”2

    ๐‘Ž2

    2๐‘Ž3sin (๐œƒ3โˆ’ 3๐œƒ2)

    +๐›ฝ5

    4๐œ”2

    ๐‘Ž2

    3๐‘Ž1sin ๐œƒ2+3๐›ฝ7

    8๐œ”2

    ๐‘Ž3

    1sin ๐œƒ2

    โˆ’๐›ฝ10

    8๐œ”2

    ๐‘Ž1๐‘Ž2๐‘Ž3sin (๐œƒ3โˆ’ 2๐œƒ2) = 0,

    ๐‘Ž2(๐œŽ2โˆ’ ๐œŽ1) โˆ’ {

    ๐œ‡2

    2

    8๐œ”2

    โˆ’ฮ“2

    2๐œ”2

    }๐‘Ž2

    + {(๐œŽ1โˆ’ ๐œŽ2) ๐‘“2

    4๐œ”2

    2

    โˆ’๐‘“2

    2๐œ”2

    } cos (๐œƒ1โˆ’ ๐œƒ2)

    +๐œ‡2๐‘“2

    8๐œ”2

    2

    sin (๐œƒ1โˆ’ ๐œƒ2) +

    ๐›ฝ1

    8๐œ”2

    ๐‘Ž2

    1๐‘Ž2cos 2๐œƒ

    2

    +๐›ฝ1

    4๐œ”2

    ๐‘Ž2

    1๐‘Ž2+๐›ฝ2

    8๐œ”2

    ๐‘Ž2

    1๐‘Ž3cos (๐œƒ

    3โˆ’ ๐œƒ2)

    +3๐›ฝ3

    8๐œ”2

    ๐‘Ž2

    2๐‘Ž1cos ๐œƒ2+๐›ฝ4

    8๐œ”2

    ๐‘Ž2

    2๐‘Ž3cos (๐œƒ

    3โˆ’ 3๐œƒ2)

    +๐›ฝ5

    4๐œ”2

    ๐‘Ž2

    3๐‘Ž1cos ๐œƒ2+๐›ฝ6

    4๐œ”2

    ๐‘Ž2

    3๐‘Ž2+3๐›ฝ7

    8๐œ”2

    ๐‘Ž3

    1cos ๐œƒ2

    +3๐›ฝ8

    8๐œ”2

    ๐‘Ž3

    2+๐›ฝ10

    8๐œ”2

    ๐‘Ž1๐‘Ž2๐‘Ž3cos (๐œƒ

    3โˆ’ 2๐œƒ2) = 0,

    โˆ’๐œ‡3

    2๐‘Ž3โˆ’๐›พ1

    8๐œ”3

    ๐‘Ž2

    1๐‘Ž2sin (๐œƒ2โˆ’ ๐œƒ3) โˆ’

    ๐›พ3

    8๐œ”3

    ๐‘Ž2

    2๐‘Ž1sin (2๐œƒ

    2โˆ’ ๐œƒ3)

    +๐›พ7

    8๐œ”3

    ๐‘Ž3

    1sin ๐œƒ3โˆ’๐›พ8

    8๐œ”3

    ๐‘Ž3

    2sin (3๐œƒ

    2โˆ’ ๐œƒ3) = 0,

    ๐‘Ž3(๐œŽ3โˆ’ 3๐œŽ1) โˆ’ {

    ๐œ‡2

    3

    8๐œ”3

    โˆ’ฮ“3

    2๐œ”3

    }๐‘Ž3+๐›พ1

    8๐œ”3

    ๐‘Ž2

    1๐‘Ž2cos (๐œƒ

    2โˆ’ ๐œƒ3)

    +๐›พ2

    4๐œ”3

    ๐‘Ž2

    1๐‘Ž3+๐›พ3

    8๐œ”3

    ๐‘Ž2

    2๐‘Ž1cos (2๐œƒ

    2โˆ’ ๐œƒ3)

    +๐›พ4

    4๐œ”3

    ๐‘Ž2

    2๐‘Ž3+๐›พ7

    8๐œ”3

    ๐‘Ž3

    1cos ๐œƒ3+๐›พ8

    8๐œ”3

    ๐‘Ž3

    2cos (3๐œƒ

    2โˆ’ ๐œƒ3)

    +3๐›พ9

    8๐œ”3

    ๐‘Ž3

    3+๐›พ10

    4๐œ”3

    ๐‘Ž1๐‘Ž2๐‘Ž3cos ๐œƒ2= 0.

    (23)

    There are six possibilities besides the trivial solution asfollows:

    (1) ๐‘Ž1ฬธ= 0, ๐‘Ž2= 0, ๐‘Ž

    3= 0 (single mode),

    (2) ๐‘Ž2ฬธ= 0, ๐‘Ž1= 0, ๐‘Ž

    3= 0 (single mode),

    (3) ๐‘Ž1ฬธ= 0, ๐‘Ž2ฬธ= 0, ๐‘Ž3= 0 (two modes),

    (4) ๐‘Ž1ฬธ= 0, ๐‘Ž3ฬธ= 0, ๐‘Ž2= 0 (two modes),

    (5) ๐‘Ž2ฬธ= 0, ๐‘Ž3ฬธ= 0, ๐‘Ž1= 0 (two modes),

    (6) ๐‘Ž1ฬธ= 0, ๐‘Ž2ฬธ= 0, ๐‘Ž3ฬธ= 0 (three modes).

    Case 1. In this case, where ๐‘Ž2= 0, ๐‘Ž

    3= 0, the frequency

    response equation is given by

    9๐›ผ2

    7

    64๐œ”2

    1

    ๐‘Ž6

    1+ [๐‘…3+3๐›ผ7๐œŽ1

    4๐œ”1

    ] ๐‘Ž4

    1+ [๐‘…2+ ๐œŽ2

    1+๐œ‡2

    1๐œŽ1

    4๐œ”1

    โˆ’ฮ“1๐œŽ1

    ๐œ”1

    ] ๐‘Ž2

    1

    โˆ’๐œ‡2

    1๐‘“2

    1

    64๐œ”4

    1

    โˆ’ ๐‘…2

    1= 0.

    (24)

    Case 2. In this case, where ๐‘Ž1= 0, ๐‘Ž

    3= 0, the frequency

    response equation is given by

    9๐›ฝ2

    8

    64๐œ”2

    2

    ๐‘Ž6

    2+ [๐‘„3+3๐›ฝ8(๐œŽ2โˆ’ ๐œŽ1)

    4๐œ”2

    ] ๐‘Ž4

    2

    + [๐‘„2+ (๐œŽ2โˆ’ ๐œŽ1)2โˆ’๐œ‡2

    2(๐œŽ2โˆ’ ๐œŽ1)

    4๐œ”2

    +ฮ“2(๐œŽ2โˆ’ ๐œŽ1)

    ๐œ”2

    ] ๐‘Ž2

    2

    โˆ’๐œ‡2

    2๐‘“2

    2

    64๐œ”4

    2

    โˆ’ ๐‘„2

    1= 0.

    (25)

    Case 3. In this case, where ๐‘Ž3= 0, the frequency response

    equations are given by

    9๐›ผ2

    7

    64๐œ”2

    1

    ๐‘Ž6

    1+ [๐‘…3+3๐›ผ7๐œŽ1

    4๐œ”1

    ] ๐‘Ž4

    1+ [๐‘…2+ ๐œŽ2

    1+๐œ‡2

    1๐œŽ1

    4๐œ”1

    โˆ’ฮ“1๐œŽ1

    ๐œ”1

    ] ๐‘Ž2

    1

    โˆ’๐œ‡2

    1๐‘“2

    1

    64๐œ”4

    1

    โˆ’ ๐‘…2

    1โˆ’9๐›ผ2

    1

    64๐œ”2

    1

    ๐‘Ž4

    1๐‘Ž2

    2โˆ’9๐›ผ1๐›ผ8

    32๐œ”2

    1

    ๐‘Ž2

    1๐‘Ž4

    2

    โˆ’9๐›ผ2

    8

    64๐œ”2

    1

    ๐‘Ž6

    2+3๐‘…1๐›ผ8

    4๐œ”1

    ๐‘Ž3

    2+3๐‘…1๐›ผ1

    4๐œ”1

    ๐‘Ž2

    1๐‘Ž2= 0,

    9๐›ฝ2

    8

    64๐œ”2

    2

    ๐‘Ž6

    2+ [๐‘„3+3๐›ฝ8(๐œŽ2โˆ’ ๐œŽ1)

    4๐œ”2

    ] ๐‘Ž4

    2

    + [๐‘„2+ (๐œŽ2โˆ’ ๐œŽ1)2โˆ’๐œ‡2

    2(๐œŽ2โˆ’ ๐œŽ1)

    4๐œ”2

    +ฮ“2(๐œŽ2โˆ’ ๐œŽ1)

    ๐œ”2

    ] ๐‘Ž2

    2

    โˆ’๐œ‡2

    2๐‘“2

    2

    64๐œ”4

    2

    โˆ’ ๐‘„2

    1+3๐‘„1๐›ฝ3

    4๐œ”2

    ๐‘Ž2

    2๐‘Ž1+3๐‘„1๐›ฝ7

    4๐œ”2

    ๐‘Ž3

    1+๐‘„1๐›ฝ1

    4๐œ”2

    ๐‘Ž2

    1๐‘Ž2

    โˆ’9๐›ฝ2

    3

    64๐œ”2

    2

    ๐‘Ž4

    2๐‘Ž2

    1โˆ’ [

    ๐›ฝ2

    1

    64๐œ”2

    2

    +9๐›ฝ3๐›ฝ7

    32๐œ”2

    2

    ] ๐‘Ž4

    1๐‘Ž2

    2โˆ’9๐›ฝ2

    7

    64๐œ”2

    2

    ๐‘Ž6

    1

    โˆ’3๐›ฝ1๐›ฝ7

    32๐œ”2

    2

    ๐‘Ž5

    1๐‘Ž2โˆ’3๐›ฝ1๐›ฝ3

    32๐œ”2

    2

    ๐‘Ž3

    1๐‘Ž3

    2= 0.

    (26)

    Case 4. In this case, where ๐‘Ž2= 0, the frequency response

    equations are given by

    9๐›ผ2

    7

    64๐œ”2

    1

    ๐‘Ž6

    1+ [๐‘…3+3๐›ผ7๐œŽ1

    4๐œ”1

    ] ๐‘Ž4

    1+ [๐‘…2+ ๐œŽ2

    1+๐œ‡2

    1๐œŽ1

    4๐œ”1

    โˆ’ฮ“1๐œŽ1

    ๐œ”1

    ] ๐‘Ž2

    1

    โˆ’๐œ‡2

    1๐‘“2

    1

    64๐œ”4

    1

    โˆ’ ๐‘…2

    1โˆ’๐›ผ2

    2

    64๐œ”2

    1

    ๐‘Ž4

    1๐‘Ž2

    3+๐‘…1๐›ผ2

    4๐œ”1

    ๐‘Ž2

    1๐‘Ž3= 0,

  • 10 Mathematical Problems in Engineering

    0 50 100 150 200โˆ’1

    โˆ’0.5

    0

    0.5

    1

    Timeโˆ’0.4 โˆ’0.2 0 0.2 0.4

    โˆ’4

    โˆ’2

    0

    2

    4

    Velo

    city

    0 50 100 150 200โˆ’0.4

    โˆ’0.2

    0

    0.2

    0.4

    Timeโˆ’0.2 โˆ’0.1 0 0.1 0.2

    โˆ’1

    โˆ’0.5

    0

    0.5

    1

    Velo

    city

    0 50 100 150 200โˆ’0.4

    โˆ’0.2

    0

    0.2

    0.4

    Timeโˆ’0.2 โˆ’0.1 0 0.1 0.2โˆ’1

    โˆ’0.5

    0

    0.5

    1Ve

    loci

    ty

    Am

    plitu

    deu1

    Am

    plitu

    deu2

    Am

    plitu

    deu3

    u1

    u2

    u3

    Figure 2: Time response and phase-plane diagrams of the system for nonresonance case.

    9๐›พ2

    9

    64๐œ”2

    3

    ๐‘Ž6

    3+ [๐พ2+3๐›พ9(๐œŽ3โˆ’ 3๐œŽ1)

    4๐œ”3

    ] ๐‘Ž4

    3

    + [๐พ1+ (๐œŽ3โˆ’ 3๐œŽ1)2โˆ’๐œ‡2

    3(๐œŽ3โˆ’ 3๐œŽ1)

    4๐œ”3

    +ฮ“3(๐œŽ3โˆ’ 3๐œŽ1)

    ๐œ”3

    ] ๐‘Ž2

    3

    โˆ’๐›พ2

    7

    64๐œ”2

    3

    ๐‘Ž6

    1= 0.

    (27)

    Case 5. In this case, where ๐‘Ž1= 0, the frequency response

    equations are given by

    9๐›ฝ2

    8

    64๐œ”2

    2

    ๐‘Ž6

    2+ [๐‘„3+3๐›ฝ8(๐œŽ2โˆ’ ๐œŽ1)

    4๐œ”2

    ] ๐‘Ž4

    2

    + [๐‘„2+ (๐œŽ2โˆ’ ๐œŽ1)2โˆ’๐œ‡2

    2(๐œŽ2โˆ’ ๐œŽ1)

    4๐œ”2

    +ฮ“2(๐œŽ2โˆ’ ๐œŽ1)

    ๐œ”2

    ] ๐‘Ž2

    2

    โˆ’๐œ‡2

    2๐‘“2

    2

    64๐œ”4

    2

    โˆ’ ๐‘„2

    1+๐‘„1๐›ฝ4

    4๐œ”2

    ๐‘Ž2

    2๐‘Ž3โˆ’๐›ฝ2

    4

    64๐œ”2

    2

    ๐‘Ž4

    2๐‘Ž2

    3= 0,

    9๐›พ2

    9

    64๐œ”2

    3

    ๐‘Ž6

    3+ [๐พ2+3๐›พ9(๐œŽ3โˆ’ 3๐œŽ1)

    4๐œ”3

    ] ๐‘Ž4

    3

    + [๐พ1+ (๐œŽ3โˆ’ 3๐œŽ1)2โˆ’๐œ‡2

    3(๐œŽ3โˆ’ 3๐œŽ1)

    4๐œ”3

    +ฮ“3(๐œŽ3โˆ’ 3๐œŽ1)

    ๐œ”3

    ] ๐‘Ž2

    3

    โˆ’๐›พ2

    8

    64๐œ”2

    3

    ๐‘Ž6

    2= 0.

    (28)

    Case 6. In this case, where ๐‘Ž1ฬธ= 0, ๐‘Ž2ฬธ= 0, and ๐‘Ž

    3ฬธ= 0, this is the

    practical case, the frequency response equations are given by

    9๐›ผ2

    7

    64๐œ”2

    1

    ๐‘Ž6

    1+ [๐‘…3+3๐›ผ7๐œŽ1

    4๐œ”1

    ] ๐‘Ž4

    1+ [๐‘…2+ ๐œŽ2

    1+๐œ‡2

    1๐œŽ1

    4๐œ”1

    โˆ’ฮ“1๐œŽ1

    ๐œ”1

    ] ๐‘Ž2

    1

    โˆ’๐œ‡2

    1๐‘“2

    1

    64๐œ”4

    1

    โˆ’ ๐‘…2

    1+๐‘…1๐›ผ2

    4๐œ”1

    ๐‘Ž2

    1๐‘Ž3+๐‘…1๐›ผ6

    2๐œ”1

    ๐‘Ž2๐‘Ž2

    3+๐‘…1๐›ผ4

    4๐œ”1

    ๐‘Ž2

    2๐‘Ž3

    +3๐‘…1๐›ผ8

    4๐œ”1

    ๐‘Ž3

    2+3๐‘…1๐›ผ1

    4๐œ”1

    ๐‘Ž2

    1๐‘Ž2+๐‘…1๐›ผ10

    4๐œ”1

    ๐‘Ž1๐‘Ž2๐‘Ž3โˆ’๐›ผ2

    6

    16๐œ”2

    1

    ๐‘Ž2

    2๐‘Ž4

    3

  • Mathematical Problems in Engineering 11A

    mpl

    itude

    u3

    0 50 100 150 200โˆ’2

    โˆ’1

    0

    1

    2

    Timeโˆ’2 โˆ’1 0 1 2

    โˆ’10

    0

    10

    Velo

    city

    0 50 100 150 200โˆ’2

    โˆ’1

    0

    1

    2

    Time

    โˆ’2 โˆ’1 0 1 2โˆ’10

    โˆ’5

    0

    5

    10

    Velo

    city

    0 50 100 150 200โˆ’0.5

    0

    0.5

    Timeโˆ’0.4 โˆ’0.2 0 0.2 0.4

    โˆ’10

    โˆ’5

    0

    5

    10Ve

    loci

    ty

    Am

    plitu

    deu1

    Am

    plitu

    deu2

    u1

    u2

    u3

    Figure 3: Time response and phase-plane diagrams of the system at simultaneous resonance case, ฮฉ3โ‰… ๐œ”1, ๐œ”2โ‰… ๐œ”1, and ๐œ”

    3โ‰… 3๐œ”1.

    โˆ’๐›ผ4๐›ผ6

    16๐œ”2

    1

    ๐‘Ž3

    2๐‘Ž3

    3โˆ’๐›ผ2

    2

    64๐œ”2

    1

    ๐‘Ž4

    1๐‘Ž2

    3โˆ’9๐›ผ2

    1

    64๐œ”2

    1

    ๐‘Ž4

    1๐‘Ž2

    2โˆ’9๐›ผ1๐›ผ8

    32๐œ”2

    1

    ๐‘Ž2

    1๐‘Ž4

    2

    โˆ’9๐›ผ2

    8

    64๐œ”2

    1

    ๐‘Ž6

    2โˆ’3๐›ผ4๐›ผ8

    32๐œ”2

    1

    ๐‘Ž5

    2๐‘Ž3โˆ’3๐›ผ8๐›ผ10

    32๐œ”2

    1

    ๐‘Ž1๐‘Ž4

    2๐‘Ž3โˆ’๐›ผ2๐›ผ10

    32๐œ”2

    1

    ๐‘Ž3

    1๐‘Ž2๐‘Ž2

    3

    โˆ’๐›ผ4๐›ผ10

    32๐œ”2

    1

    ๐‘Ž1๐‘Ž3

    2๐‘Ž2

    3โˆ’๐›ผ6๐›ผ10

    16๐œ”2

    1

    ๐‘Ž1๐‘Ž2

    2๐‘Ž3

    3โˆ’๐›ผ2๐›ผ6

    16๐œ”2

    1

    ๐‘Ž2

    1๐‘Ž2๐‘Ž3

    3

    โˆ’3๐›ผ1๐›ผ10

    32๐œ”2

    1

    ๐‘Ž3

    1๐‘Ž2

    2๐‘Ž3โˆ’3๐›ผ1๐›ผ2

    32๐œ”2

    1

    ๐‘Ž4

    1๐‘Ž2๐‘Ž3โˆ’ ๐‘…4๐‘Ž2

    1๐‘Ž2

    2๐‘Ž2

    3

    โˆ’ ๐‘…5๐‘Ž4

    2๐‘Ž2

    3โˆ’ ๐‘…6๐‘Ž3

    2๐‘Ž2

    1๐‘Ž3= 0,

    9๐›ฝ2

    8

    64๐œ”2

    2

    ๐‘Ž6

    2+ [๐‘„3+3๐›ฝ8(๐œŽ2โˆ’ ๐œŽ1)

    4๐œ”2

    ] ๐‘Ž4

    2

    + [๐‘„2+ (๐œŽ2โˆ’ ๐œŽ1)2โˆ’๐œ‡2

    2(๐œŽ2โˆ’ ๐œŽ1)

    4๐œ”2

    +ฮ“2(๐œŽ2โˆ’ ๐œŽ1)

    ๐œ”2

    ] ๐‘Ž2

    2

    โˆ’๐œ‡2

    2๐‘“2

    2

    64๐œ”4

    2

    โˆ’ ๐‘„2

    1+3๐‘„1๐›ฝ3

    4๐œ”2

    ๐‘Ž2

    2๐‘Ž1+3๐‘„1๐›ฝ7

    4๐œ”2

    ๐‘Ž3

    1+๐‘„1๐›ฝ1

    4๐œ”2

    ๐‘Ž2

    1๐‘Ž2

    +๐‘„1๐›ฝ4

    4๐œ”2

    ๐‘Ž2

    2๐‘Ž3+๐‘„1๐›ฝ5

    2๐œ”2

    ๐‘Ž1๐‘Ž2

    3+๐‘„1๐›ฝ2

    4๐œ”2

    ๐‘Ž2

    1๐‘Ž3+๐‘„1๐›ฝ10

    4๐œ”2

    ๐‘Ž1๐‘Ž2๐‘Ž3

    โˆ’3๐›ฝ1๐›ฝ7

    32๐œ”2

    2

    ๐‘Ž5

    1๐‘Ž2โˆ’9๐›ฝ2

    3

    64๐œ”2

    2

    ๐‘Ž4

    2๐‘Ž2

    1โˆ’9๐›ฝ2

    7

    64๐œ”2

    2

    ๐‘Ž6

    1โˆ’๐›ฝ2

    4

    64๐œ”2

    2

    ๐‘Ž4

    2๐‘Ž2

    3

    โˆ’3๐›ฝ1๐›ฝ3

    32๐œ”2

    2

    ๐‘Ž3

    1๐‘Ž3

    2โˆ’๐›ฝ2

    5

    16๐œ”2

    2

    ๐‘Ž2

    1๐‘Ž4

    3โˆ’๐›ฝ2๐›ฝ5

    16๐œ”2

    2

    ๐‘Ž3

    1๐‘Ž3

    3โˆ’3๐›ฝ3๐›ฝ4

    32๐œ”2

    2

    ๐‘Ž1๐‘Ž4

    2๐‘Ž3

    โˆ’3๐›ฝ2๐›ฝ7

    32๐œ”2

    2

    ๐‘Ž5

    1๐‘Ž3โˆ’๐›ฝ4๐›ฝ5

    16๐œ”2

    2

    ๐‘Ž1๐‘Ž2

    2๐‘Ž3

    3โˆ’๐›ฝ5๐›ฝ10

    16๐œ”2

    2

    ๐‘Ž2

    1๐‘Ž2๐‘Ž3

    2โˆ’๐›ฝ4๐›ฝ10

    32๐œ”2

    2

    ๐‘Ž1๐‘Ž3

    2๐‘Ž2

    3

    โˆ’ ๐‘„4๐‘Ž2

    1๐‘Ž2

    2๐‘Ž2

    3โˆ’ ๐‘„5๐‘Ž4

    1๐‘Ž2

    2โˆ’ ๐‘„6๐‘Ž4

    1๐‘Ž2

    3โˆ’ ๐‘„7๐‘Ž3

    1๐‘Ž2

    2๐‘Ž3โˆ’ ๐‘„8๐‘Ž2

    1๐‘Ž3

    2๐‘Ž3

    โˆ’ ๐‘„9๐‘Ž3

    1๐‘Ž2๐‘Ž2

    3โˆ’ ๐‘„10๐‘Ž4

    1๐‘Ž2๐‘Ž3= 0,

    9๐›พ2

    9

    64๐œ”2

    3

    ๐‘Ž6

    3+ [๐พ2+3๐›พ9(๐œŽ3โˆ’ 3๐œŽ1)

    4๐œ”3

    ] ๐‘Ž4

    3

    +[๐พ1+ (๐œŽ3โˆ’3๐œŽ1)2โˆ’๐œ‡2

    3(๐œŽ3โˆ’ 3๐œŽ1)

    4๐œ”3

    +ฮ“3(๐œŽ3โˆ’ 3๐œŽ1)

    ๐œ”3

    ] ๐‘Ž2

    3

  • 12 Mathematical Problems in Engineering

    0 50 100 150 200โˆ’2

    โˆ’1

    0

    1

    2

    3

    Time0 50 100 150 200

    โˆ’3

    โˆ’2

    โˆ’1

    0

    1

    2

    3

    Time

    0 50 100 150 200

    โˆ’0.4

    โˆ’0.2

    0

    0.2

    0.4

    0.6

    0.8

    Time

    Numerical solution๐‘Ž1(๐‘ก) perturbation solution

    Numerical solution๐‘Ž2(๐‘ก) perturbation solution

    Numerical solution๐‘Ž3(๐‘ก) perturbation solution

    Am

    plitu

    deu1

    Am

    plitu

    deu2

    Am

    plitu

    deu3

    Figure 4: Comparison between numerical solution (using RKM) and analytical solution (using perturbation method) of the system atresonance case, ฮฉ

    3โ‰… ๐œ”1, ๐œ”2โ‰… ๐œ”1, and ๐œ”

    3โ‰… 3๐œ”1.

    โˆ’๐›พ2

    8

    64๐œ”2

    3

    ๐‘Ž6

    2โˆ’

    ๐›พ2

    7

    64๐œ”2

    3

    ๐‘Ž6

    1โˆ’๐›พ1๐›พ7

    32๐œ”2

    3

    ๐‘Ž5

    1๐‘Ž2โˆ’๐›พ3๐›พ8

    32๐œ”2

    3

    ๐‘Ž1๐‘Ž5

    2

    โˆ’ ๐พ3๐‘Ž4

    1๐‘Ž2

    2โˆ’ ๐พ4๐‘Ž2

    1๐‘Ž4

    2โˆ’ ๐พ5๐‘Ž3

    1๐‘Ž2

    2= 0,

    (29)

    where

    ๐‘…1= [

    ๐‘“1

    2๐œ”1

    โˆ’๐œŽ1๐‘“1

    4๐œ”2

    1

    ] ,

    ๐‘…2= [

    ๐œ‡2

    1

    4+๐œ‡4

    1

    64๐œ”2

    1

    +ฮ“2

    1

    4๐œ”2

    1

    โˆ’ฮ“1๐œ‡2

    1

    8๐œ”2

    1

    ] ,

    ๐‘…3= [

    3๐›ผ7๐œ‡2

    1

    32๐œ”2

    1

    โˆ’3๐›ผ7ฮ“1

    8๐œ”2

    1

    ] ,

    ๐‘…4= [

    ๐›ผ2

    10

    64๐œ”2

    1

    +3๐›ผ1๐›ผ6

    16๐œ”2

    1

    +๐›ผ2๐›ผ4

    32๐œ”2

    1

    ] ,

    ๐‘…5= [

    3๐›ผ6๐›ผ8

    16๐œ”2

    1

    +๐›ผ2

    4

    64๐œ”2

    1

    ] ,

    ๐‘…6= [

    3๐›ผ1๐›ผ4

    32๐œ”2

    1

    +3๐›ผ2๐›ผ8

    32๐œ”2

    1

    ] ,

    ๐‘„1= [

    ๐‘“2

    2๐œ”2

    โˆ’(๐œŽ1โˆ’ ๐œŽ2) ๐‘“2

    4๐œ”2

    2

    ] ,

  • Mathematical Problems in Engineering 13

    200 200.5 201 201.5 202 202.5 203โˆ’0.5

    0

    0.5

    Time200 200.5 201 201.5 202 202.5 203

    โˆ’0.2

    โˆ’0.1

    0

    0.1

    0.2

    Time

    200 200.5 201 201.5 202 202.5 203โˆ’0.2

    โˆ’0.1

    0

    0.1

    0.2

    Time

    RKMFDM

    RKMFDM

    RKMFDM

    Am

    plitu

    deu1

    Am

    plitu

    deu2

    Am

    plitu

    deu3

    Figure 5: Time response of composite laminated rectangular plate using RKM and FDM.

    ๐‘„2= [

    ๐œ‡2

    2

    4+๐œ‡4

    2

    64๐œ”2

    2

    +ฮ“2

    2

    4๐œ”2

    2

    โˆ’ฮ“2๐œ‡2

    2

    8๐œ”2

    2

    ] ,

    ๐‘„3= [

    3๐›ฝ8ฮ“2

    8๐œ”2

    2

    โˆ’3๐›ฝ8๐œ‡2

    2

    32๐œ”2

    2

    ] ,

    ๐‘„4= [

    ๐›ฝ2

    10

    64๐œ”2

    2

    +3๐›ฝ3๐›ฝ5

    16๐œ”2

    2

    +๐›ฝ2๐›ฝ4

    32๐œ”2

    2

    ] ,

    ๐‘„5= [

    ๐›ฝ2

    1

    64๐œ”2

    2

    +9๐›ฝ3๐›ฝ7

    32๐œ”2

    2

    ] ,

    ๐‘„6= [

    ๐›ฝ2

    2

    64๐œ”2

    2

    +3๐›ฝ5๐›ฝ7

    16๐œ”2

    2

    ] ,

    ๐‘„7= [

    3๐›ฝ2๐›ฝ3

    32๐œ”2

    2

    +3๐›ฝ4๐›ฝ7

    32๐œ”2

    2

    +๐›ฝ1๐›ฝ10

    32๐œ”2

    2

    ] ,

    ๐‘„8= [

    3๐›ฝ3๐›ฝ10

    32๐œ”2

    2

    +๐›ฝ1๐›ฝ4

    32๐œ”2

    2

    ] ,

    ๐‘„9= [

    ๐›ฝ2๐›ฝ10

    32๐œ”2

    2

    +๐›ฝ1๐›ฝ5

    16๐œ”2

    2

    ] ,

    ๐‘„10= [

    3๐›ฝ7๐›ฝ10

    32๐œ”2

    2

    +๐›ฝ1๐›ฝ2

    32๐œ”2

    2

    ] ,

    ๐พ1= [

    ๐œ‡2

    3

    4+๐œ‡4

    3

    64๐œ”2

    3

    +ฮ“2

    3

    4๐œ”2

    3

    โˆ’ฮ“3๐œ‡2

    3

    8๐œ”2

    3

    ] ,

    ๐พ2= [

    3๐›พ9ฮ“3

    8๐œ”2

    3

    โˆ’3๐›พ9๐œ‡2

    3

    32๐œ”2

    3

    ] ,

    ๐พ3= [

    ๐›พ2

    1

    64๐œ”2

    3

    +๐›พ3๐›พ7

    32๐œ”2

    3

    ] ,

    ๐พ4= [

    ๐›พ2

    3

    64๐œ”2

    3

    +๐›พ1๐›พ8

    32๐œ”2

    3

    ] ,

    ๐พ5= [

    ๐›พ1๐›พ3

    32๐œ”2

    3

    +๐›พ7๐›พ8

    32๐œ”2

    3

    ] .

    (30)

  • 14 Mathematical Problems in Engineering

    โˆ’1.5 โˆ’1 โˆ’0.5 0 0.5 1 1.5

    2

    4

    6

    8

    10

    Analytical solutionNumerical solution

    ๐œŽ1a 1

    Figure 6: Comparison between analytical prediction using multiple time scale and numerical integration of the first mode.

    โˆ’1 โˆ’0.5 0 0.5 1

    5

    10

    15

    20

    0.2

    0.1

    0.3

    a 1

    ๐œŽ1

    Figure 7: Effects of the linear damping ๐œ‡1.

    โˆ’1.5 โˆ’1 โˆ’0.5 0 0.5 1 1.5

    2

    4

    6

    8

    10

    12

    141.7

    2.3

    4.3

    a 1

    ๐œŽ1

    Figure 8: Effects of the natural frequency ๐œ”1.

    โˆ’1.5 โˆ’1 โˆ’0.5 0 0.5 1 1.5

    5

    10

    15

    20

    4

    8

    3

    a 1

    ๐œŽ1

    Figure 9: Effects of the external excitation ๐‘“1.

  • Mathematical Problems in Engineering 15

    โˆ’1.5 โˆ’1 โˆ’0.5 0 0.5 1 1.5

    2

    4

    6

    8

    10

    12

    0.06

    โˆ’0.06

    0.01

    a 1๐œŽ1

    Figure 10: Effects of the nonlinear parameter ๐›ผ7.

    โˆ’1.5 โˆ’1 โˆ’0.5 0 0.5 1 1.5

    2

    4

    6

    8

    10

    0.5510

    a 1

    ๐œŽ1

    Figure 11: Effects of the parametric excitation ๐‘“14.

    โˆ’1.5 โˆ’1 โˆ’0.5 0 0.5 1 1.5

    123456

    Analytical solutionNumerical solution

    a 2

    ๐œŽ2

    Figure 12: Comparison between analytical prediction using multiple time scale and numerical integration of the second mode.

    โˆ’1.5 โˆ’1 โˆ’0.5

    โˆ’0.08

    0

    0.2

    0.5 1 1.50

    2

    0.01

    4

    6

    a 2

    ๐œŽ2

    Figure 13: Effects of the nonlinear parameter ๐›ฝ8.

  • 16 Mathematical Problems in Engineering

    โˆ’1 โˆ’0.5 0 0.5

    0.1

    0.2

    0.3

    10

    4

    8

    a 2

    ๐œŽ2

    Figure 14: Effects of the linear damping ๐œ‡2.

    โˆ’1.5 โˆ’1 โˆ’0.5 0

    4

    2.2

    0.5 1 1.50

    2

    4

    6

    8

    a 2

    ๐œŽ2

    Figure 15: Effects of the natural frequency ๐œ”2.

    โˆ’1.5 โˆ’1 โˆ’0.5 0 0.5 1 1.50

    2

    4

    6

    8

    2

    4

    6

    a 2

    ๐œŽ2

    Figure 16: Effects of the external excitation ๐‘“2.

    In the frequency response curves, the stable (unstable)steady-state solutions have been represented by solid (dotted)lines.

    4. Numerical Results and Discussion

    To study the behavior of the system, the Runge-Kutta fourth-order method (RKM) was applied to (4a), (4b), and (4c)

    governing the oscillating system. A good criterion of bothstability and dynamic chaos is the phase plane trajectories.Figure 2 illustrates the response and the phase-plane for thenonresonant system at some practical values of the equationparameters: ๐œ‡

    1= 0.05, ๐œ‡

    2= 0.05, ๐œ‡

    3= 0.05, ๐›ผ

    1= ๐›ฝ1= ๐›พ1=

    1.5, ๐›ผ2= ๐›ฝ2= ๐›พ2= 1.9, ๐›ผ

    3= ๐›ฝ3= ๐›พ3= 0.4, ๐›ผ

    4= ๐›ฝ4= ๐›พ4=

    0.6, ๐›ผ5= ๐›ฝ5= ๐›พ5= 0.6, ๐›ผ

    6= ๐›ฝ6= ๐›พ6= 0.2, ๐›ผ

    7= ๐›ฝ7= ๐›พ7=

    0.01, ๐›ผ8= ๐›ฝ8= ๐›พ8= 0.01, ๐›ผ

    9= ๐›ฝ9= ๐›พ9= 0.4, ๐›ผ

    10= ๐›ฝ10=

    ๐›พ10= 1.8, ฮฉ

    1= 6.4, ฮฉ

    2= 6.1, ฮฉ

    3= 5.7, ฮฉ

    4= 2, ๐œ”

    1= 4.7,

  • Mathematical Problems in Engineering 17

    โˆ’2 โˆ’1 0 1 20

    2

    4

    6

    Am

    plitu

    des

    ๐œŽ1

    a1

    a1

    a2a2

    a3a3

    Figure 17: Effects of the detuning parameter ๐œŽ1.

    โˆ’1 0 1

    4

    6

    1

    โˆ’1 0 10.5

    1.5

    2.5

    1

    โˆ’1 0 1

    0.2

    0.6

    1

    1.4

    1

    f1 = 10

    f1 = 10

    f1 = 10

    a 1

    a 2

    a 3

    ๐œŽ1

    ๐œŽ1๐œŽ1

    Figure 18: Effects of the external excitation force ๐‘“1.

    ๐œ”2= 2.7, ๐œ”

    3= 13.1, ๐‘“

    1= ๐‘“2= 4, ๐‘“

    3= 20.5, ๐‘“

    11= ๐‘“21= ๐‘“31=

    0.1,๐‘“12= ๐‘“22= ๐‘“32= 0.2, and๐‘“

    14= ๐‘“24= ๐‘“34= 0.5. Figure 3

    shows the steady-state amplitudes and phase plane of thesystem at simultaneous resonance caseฮฉ

    3โ‰… ๐œ”1,๐œ”2โ‰… ๐œ”1, and

    ๐œ”3โ‰… 3๐œ”1. It is clear from Figure 3 that the steady-state ampli-

    tude of the first, second, and thirdmodes is increased to about

    370%, 890%, and 260%, respectively, of its value shown inFigure 2. Also, it can be seen that the time response of thesystem is tuned with multilimit cycle.

    It is quite clear that such case is undesirable in thedesign of such system because it represents one of the worstbehaviors of the system. Such case should be avoided as

  • 18 Mathematical Problems in Engineering

    โˆ’2 โˆ’1 0 1 22

    3

    4

    5

    6

    7

    2.5

    1.5

    โˆ’2 0 10.5

    1.5

    2.5

    3.5

    4.5

    1.5

    2.5

    0 1

    0.2

    0.6

    1.2

    2.5

    1.5

    โˆ’1

    โˆ’1

    a 2a 1

    a 3

    ๐œŽ1

    ๐œŽ1๐œŽ1

    ๐›ผ1 = 0.5

    ๐›ฝ1 = 0.5

    ๐›พ1 = 0.5

    Figure 19: Effects of the nonlinear parameters (๐›ผ1, ๐›ฝ1, and ๐›พ

    1coupling terms).

    working condition for the system. It is advised for such systemnot to have ๐œ”

    2= ๐œ”1or ๐œ”3= 3๐œ”1. Figure 4 shows the com-

    parison between numerical integration for the system equa-tion (4a), (4b), and (4c) solid lines and the amplitude-phase modulating equation (20) dashed lines. We foundthat all predictions from analytical solutions dashed linesare in good agreement with the numerical simulation solidlines.

    4.1. FDM with Approximation O(๐‘2). The infinite equations(2a)โ€“(2e) will be solved via a finite differencemethod (FDM).We briefly describe the procedure here. More details areavailable in [23, 26].The infinite dimensional equations (2a)โ€“(2e) can be reduced to the finite dimensional one via the finitedifference method with second-order approximation ๐‘‚(๐‘2).Namely, at each mesh node the following system of ordinary

    differential equations is obtained:

    ๐ฟ1,๐‘(๐‘๐‘ฅ๐‘ฅ, ๐‘๐‘ฅ๐‘ฆ) = ๐ผ0(๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—+ ๐ฝ1( ฬˆ๐œ™๐‘ฅ)๐‘–,๐‘—

    โˆ’2

    3โ„Ž2๐‘๐ผ3((๏ฟฝฬˆ๏ฟฝ0)๐‘–+1,๐‘—

    โˆ’ (๏ฟฝฬˆ๏ฟฝ0)๐‘–โˆ’1,๐‘—

    ) ,

    ๐ฟ2,๐‘(๐‘๐‘ฅ๐‘ฆ, ๐‘๐‘ฆ๐‘ฆ) = ๐ผ0(Vฬˆ0)๐‘–,๐‘—+ ๐ฝ1( ฬˆ๐œ™๐‘ฆ)๐‘–,๐‘—

    โˆ’2

    3โ„Ž2๐‘๐ผ3((๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—+1

    โˆ’ (๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—โˆ’1

    ) ,

    ๐ฟ3,๐‘(๐‘„๐‘ฅ, ๐‘„๐‘ฆ, ๐‘๐‘ฅ๐‘ฅ, ๐‘ค0, ๐‘๐‘ฅ๐‘ฆ)

    = ๐ผ0(๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—โˆ’

    16

    9โ„Ž4๐‘2๐ผ6((๏ฟฝฬˆ๏ฟฝ0)๐‘–+1,๐‘—

    โˆ’ 2(๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—+ (๏ฟฝฬˆ๏ฟฝ0)๐‘–+1,๐‘—

    +(๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—+1

    โˆ’2(๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—+(๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—+1

    )

  • Mathematical Problems in Engineering 19

    โˆ’2 โˆ’1 0 1

    3

    4

    5

    6

    10

    5

    โˆ’1 0 10.5

    1

    1.5

    2

    2.5

    5

    10

    โˆ’2 โˆ’1 0 1

    0.2

    0.6

    1

    5

    10

    ๐œŽ1

    ๐œŽ1๐œŽ1

    a 2a1

    a 3

    ๐›ผ2 = 0.1๐›ฝ2 = 0.1

    ๐›พ2 = 0.1

    Figure 20: Effects of the nonlinear parameters (๐›ผ2, ๐›ฝ2, and ๐›พ

    2coupling terms).

    +4

    3โ„Ž2๐‘2๐ผ3((๏ฟฝฬˆ๏ฟฝ0)๐‘–+1,๐‘—

    โˆ’ (๏ฟฝฬˆ๏ฟฝ0)๐‘–โˆ’1,๐‘—

    + (Vฬˆ0)๐‘–,๐‘—+1

    โˆ’ (Vฬˆ0)๐‘–,๐‘—โˆ’1

    )

    +๐ฝ4

    2๐‘(( ฬˆ๐œ™๐‘ฅ)๐‘–+1,๐‘—

    โˆ’ ( ฬˆ๐œ™๐‘ฅ)๐‘–โˆ’1,๐‘—

    + ( ฬˆ๐œ™๐‘ฆ)๐‘–,๐‘—+1

    โˆ’ ( ฬˆ๐œ™๐‘ฆ)๐‘–,๐‘—โˆ’1

    ) ,

    ๐ฟ4,๐‘(๐‘€๐‘ฅ๐‘ฅ,๐‘€๐‘ฅ๐‘ฆ) = ๐ฝ1(๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—+ ๐‘˜2( ฬˆ๐œ™๐‘ฅ)๐‘–,๐‘—

    โˆ’2๐ฝ4

    3โ„Ž2๐‘((๏ฟฝฬˆ๏ฟฝ0)๐‘–+1,๐‘—

    โˆ’ (๏ฟฝฬˆ๏ฟฝ0)๐‘–โˆ’1,๐‘—

    ) ,

    ๐ฟ5,๐‘(๐‘€๐‘ฅ๐‘ฆ,๐‘€๐‘ฆ๐‘ฆ) = ๐ฝ1(Vฬˆ0)๐‘–,๐‘—+ ๐‘˜2( ฬˆ๐œ™๐‘ฆ)๐‘–,๐‘—

    โˆ’2๐ฝ4

    3โ„Ž2๐‘((๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—+1

    โˆ’ (๏ฟฝฬˆ๏ฟฝ0)๐‘–,๐‘—โˆ’1

    ) ,

    (๐‘– = 1, 2, . . . , ๐‘›) , (๐‘— = 1, 2, . . . , ๐‘›) ,

    (31)

    where ๐‘› denotes the partition number regarding a spatialcoordinate, ๐‘ is the computational step regarding spatialcoordinate, and ๐ฟ

    1,๐‘(โ‹…), ๐ฟ2,๐‘(โ‹…), ๐ฟ3,๐‘(โ‹…), ๐ฟ4,๐‘(โ‹…), and ๐ฟ

    5,๐‘(โ‹…) are

    the difference operators as follows:

    ๐ฟ1,๐‘(๐‘๐‘ฅ๐‘ฅ, ๐‘๐‘ฅ๐‘ฆ) =

    1

    2๐‘((๐‘๐‘ฅ๐‘ฅ)๐‘–+1,๐‘—

    โˆ’ (๐‘๐‘ฅ๐‘ฅ)๐‘–โˆ’1,๐‘—

    + (๐‘๐‘ฅ๐‘ฆ)๐‘–,๐‘—+1

    โˆ’ (๐‘๐‘ฅ๐‘ฆ)๐‘–,๐‘—โˆ’1

    ) ,

    ๐ฟ2,๐‘(๐‘๐‘ฅ๐‘ฆ, ๐‘๐‘ฆ๐‘ฆ) =

    1

    2๐‘((๐‘๐‘ฅ๐‘ฆ)๐‘–+1,๐‘—

    โˆ’ (๐‘๐‘ฅ๐‘ฆ)๐‘–โˆ’1,๐‘—

    + (๐‘๐‘ฆ๐‘ฆ)๐‘–,๐‘—+1

    โˆ’ (๐‘๐‘ฆ๐‘ฆ)๐‘–,๐‘—โˆ’1

    ) ,

  • 20 Mathematical Problems in Engineering

    ๐ฟ3,๐‘(๐‘„๐‘ฅ, ๐‘„๐‘ฆ, ๐‘๐‘ฅ๐‘ฅ, ๐‘ค0, ๐‘๐‘ฅ๐‘ฆ) =

    1

    2๐‘((๐‘„๐‘ฅ)๐‘–+1,๐‘—

    โˆ’ (๐‘„๐‘ฅ)๐‘–โˆ’1,๐‘—

    + (๐‘„๐‘ฆ)๐‘–,๐‘—+1

    โˆ’ (๐‘„๐‘ฆ)๐‘–,๐‘—โˆ’1

    )

    + ๐‘๐‘ฅ๐‘ฅ(

    (๐‘ค0)๐‘–โˆ’1,๐‘—

    โˆ’ 2(๐‘ค0)๐‘–,๐‘—+ (๐‘ค0)๐‘–+1,๐‘—

    ๐‘2) + (

    (๐‘ค0)๐‘–+1,๐‘—

    โˆ’ (๐‘ค0)๐‘–โˆ’1,๐‘—

    2๐‘)(

    (๐‘๐‘ฅ๐‘ฅ)๐‘–+1,๐‘—

    โˆ’ (๐‘๐‘ฅ๐‘ฅ)๐‘–โˆ’1,๐‘—

    2๐‘)

    + ๐‘๐‘ฅ๐‘ฆ(

    ((๐‘ค0)๐‘—+1,๐‘–+1

    โˆ’ 2(๐‘ค0)๐‘—+1,๐‘–โˆ’1

    ) ((๐‘ค0)๐‘—โˆ’1,๐‘–+1

    โˆ’ 2(๐‘ค0)๐‘—โˆ’1,๐‘–โˆ’1

    )

    4๐‘2)

    + (

    (๐‘ค0)๐‘–,๐‘—+1

    โˆ’ (๐‘ค0)๐‘–,๐‘—โˆ’1

    2๐‘)(

    (๐‘๐‘ฅ๐‘ฆ)๐‘–+1,๐‘—

    โˆ’ (๐‘๐‘ฅ๐‘ฆ)๐‘–โˆ’1,๐‘—

    2๐‘)

    + ๐‘๐‘ฅ๐‘ฆ(

    ((๐‘ค0)๐‘–+1,๐‘—+1

    โˆ’ (๐‘ค0)๐‘–+1,๐‘—โˆ’1

    ) โˆ’ ((๐‘ค0)๐‘–โˆ’1,๐‘—+1

    โˆ’ (๐‘ค0)๐‘–โˆ’1,๐‘—โˆ’1

    )

    8๐‘3)

    + (

    (๐‘ค0)๐‘–+1,๐‘—

    โˆ’ (๐‘ค0)๐‘–โˆ’1,๐‘—

    2๐‘)(

    (๐‘๐‘ฆ๐‘ฆ)๐‘–,๐‘—+1

    โˆ’ (๐‘๐‘ฆ๐‘ฆ)๐‘–,๐‘—โˆ’1

    2๐‘) + ๐‘

    ๐‘ฆ๐‘ฆ(

    (๐‘ค0)๐‘–,๐‘—โˆ’1

    โˆ’ 2(๐‘ค0)๐‘–,๐‘—+ (๐‘ค0)๐‘–,๐‘—+1

    ๐‘2)

    + (

    (๐‘ค0)๐‘–,๐‘—+1

    โˆ’ (๐‘ค0)๐‘–,๐‘—โˆ’1

    2๐‘)(

    (๐‘๐‘ฆ๐‘ฆ)๐‘–,๐‘—+1

    โˆ’ (๐‘๐‘ฆ๐‘ฆ)๐‘–,๐‘—โˆ’1

    2๐‘) +

    4

    3โ„Ž2(

    (๐‘ƒ๐‘ฅ๐‘ฅ)๐‘–โˆ’1,๐‘—

    โˆ’ 2(๐‘ƒ๐‘ฅ๐‘ฅ)๐‘–,๐‘—+ (๐‘ƒ๐‘ฅ๐‘ฅ)๐‘–+1,๐‘—

    ๐‘2)

    +4

    3โ„Ž2(2(

    ((๐‘ƒ๐‘ฅ๐‘ฆ)๐‘–+1,๐‘—+1

    โˆ’ (๐‘ƒ๐‘ฅ๐‘ฆ)๐‘–โˆ’1,๐‘—+1

    ) โˆ’ ((๐‘ƒ๐‘ฅ๐‘ฆ)๐‘–+1,๐‘—โˆ’1

    โˆ’ (๐‘ƒ๐‘ฅ๐‘ฆ)๐‘–โˆ’1,๐‘—โˆ’1

    )

    8๐‘3)+

    (๐‘ƒ๐‘ฆ๐‘ฆ)๐‘–,๐‘—โˆ’1

    โˆ’ 2(๐‘ƒ๐‘ฆ๐‘ฆ)๐‘–,๐‘—+ (๐‘ƒ๐‘ฆ๐‘ฆ)๐‘–,๐‘—+1

    ๐‘2)+ ๐‘ž,

    ๐ฟ4,๐‘(๐‘€๐‘ฅ๐‘ฅ,๐‘€๐‘ฅ๐‘ฆ) =

    1

    2๐‘((๐‘€๐‘ฅ๐‘ฅ)๐‘–+1,๐‘—

    โˆ’ (๐‘€๐‘ฅ๐‘ฅ)๐‘–โˆ’1,๐‘—

    + (๐‘€๐‘ฅ๐‘ฆ)๐‘–,๐‘—+1

    โˆ’ (๐‘€๐‘ฅ๐‘ฆ)๐‘–,๐‘—โˆ’1

    ) โˆ’ ๐‘„๐‘ฅ,

    ๐ฟ5,๐‘(๐‘€๐‘ฅ๐‘ฆ,๐‘€๐‘ฆ๐‘ฆ) =

    1

    2๐‘((๐‘€๐‘ฅ๐‘ฆ)๐‘–+1,๐‘—

    โˆ’ (๐‘€๐‘ฅ๐‘ฆ)๐‘–โˆ’1,๐‘—

    + (๐‘€๐‘ฆ๐‘ฆ)๐‘–,๐‘—+1

    โˆ’ (๐‘€๐‘ฆ๐‘ฆ)๐‘–,๐‘—โˆ’1

    ) โˆ’ ๐‘„๐‘ฆ.

    (32)

    The obtained system of (31) with the supplemented boundaryconditions equation and the initial conditions equation issolved by the fourth-order Runge-Kutta method. Figure 5shows a comparison between the time responses of the systemequations (4a), (4b), and (4c) using the Runge-Kutta offourth-order method and the time response of the problems(31), using the finite difference method at the same values ofthe parameters shown in Figure 2.

    4.2. Frequency Response Curves. When the amplitudeachieves a constant nontrivial value, a steady-state vibrationexists. Using the frequency response equations we can assessthe influence of the damping coefficients, the nonlinear para-meters, and the excitation amplitude on the steady-stateamplitudes. The frequency response equations (24)โ€“(29) arenonlinear equations in ๐‘Ž

    1, ๐‘Ž2, and ๐‘Ž

    3which are solved

    numerically.Thenumerical results are shown in Figures 6โ€“25,and in all figures the region of stability of the nonlinearsolutions is determined by applying the Routh-Hurwitz

    criterion.The solid lines stand for the stable solution, and thedotted lines stand for the unstable solution. From the geo-metry of the figures, we observe that each curve is continuousand has stable and unstable solutions.

    4.2.1. Response Curve of Case 1. To check the accuracy ofthe analytical solution derived by the multiple time scalein predicting the amplitude of the first mode, we comparethe amplitude of the first mode obtained from frequencyresponse equation of Case 1 with values obtained fromnumerical integration of (4a). Figure 6 shows a comparisonof these outputs for the first mode.The effects of the detuningparameter ๐œŽ

    1on the steady-state amplitude of the first mode

    for the stability first case, where ๐‘Ž1ฬธ= 0, ๐‘Ž2= 0, and ๐‘Ž

    3= 0, for

    the parameters ๐œ‡1= 0.2, ๐›ผ

    7= 0.01, ๐œ”

    1= 2.3, ๐‘“

    1= 4, ๐‘“

    11=

    0.1, ๐‘“12= 0.2, ๐‘“

    14= 0.5, ฮฉ

    1= 1, ฮฉ

    2= 1.2, and ฮฉ

    4= 1.4, as

    shown in Figure 6.Figures 7โ€“11, show the effects of the damping coeffi-

    cient ๐œ‡1, the first mode natural frequency ๐œ”

    1, the external

  • Mathematical Problems in Engineering 21

    โˆ’1 0 12

    4

    63

    8

    โˆ’2 0 2

    1.5

    2.5

    3.5

    8

    3

    โˆ’2 0 2

    0.2

    0.6

    1

    8

    3

    ๐œŽ1

    ๐œŽ1๐œŽ1

    a 2

    a 1

    a 3

    ๐›ผ8 = 1.5

    ๐›ฝ8 = 1.5

    ๐›พ8 = 1.5

    Figure 21: Effects of the nonlinear parameters (๐›ผ8, ๐›ฝ8, and ๐›พ

    8coupling terms).

    excitation amplitude๐‘“1, the nonlinear spring stiffness ๐›ผ

    7, and

    the parametric excitation ๐‘“14. Figures 7 and 8 show that the

    steady-state amplitude ๐‘Ž1is inversely proportional to ๐œ‡

    1and

    ๐œ”1, and also for decreasing๐œ‡

    1or๐œ”1the curve is bending to the

    left. It is clear from Figure 9 that the steady-state amplitude๐‘Ž1is increasing for increasing value of external excitation

    force ๐‘“1, and the zone of instability is increased. Figure 10

    shows that as the nonlinear spring stiffness ๐›ผ7is increased;

    the continuous curve ismoved downwards. Also, the negativeand positive values of ๐›ผ

    7produce either hard or soft spring,

    respectively, as the curve is either bent to the right or to theleft, leading to the appearance of the jump phenomenon.Theregion of stability is increased for increasing value of๐›ผ

    7. From

    Figure 11, we observe that for increasing value of parametricexcitation amplitude ๐‘“

    14, the steady-state amplitude of the

    first mode is increased, and the curve is shifted to the left.

    4.2.2. Response Curve of Case 2. Figures 12โ€“16, show thefrequency response curves for the stability of the second case,where ๐‘Ž

    2ฬธ= 0, ๐‘Ž

    1= 0, and ๐‘Ž

    3= 0. Figure 12 shows a com-

    parison of these outputs for the second mode. The effects ofthe detuning parameter ๐œŽ

    2on the steady-state amplitude of

    the second mode for the stability second case, where ๐‘Ž2ฬธ= 0,

    ๐‘Ž1= 0, ๐‘Ž

    3= 0, for the parameters: ๐œ‡

    2= 0.2, ๐›ฝ

    8= 0.01,

    ๐œ”2= 4, ๐‘“

    2= 4, ๐‘“

    21= 0.1, ๐‘“

    22= 0.2, ๐‘“

    24= 0.5, ฮฉ

    1= 1, ฮฉ

    2=

    1.2, and ฮฉ4= 1.4, as shown in Figure 12. It can be seen from

    the figure thatmaximum steady-state amplitude occurs when๐œ”2โ‰… ๐œ”1. Figure 13 shows that as the nonlinear spring stiffness

    ๐›ฝ8is increased, the continuous curve is moved downwards.

    Also, the positive and negative values of ๐›ฝ8produce either

    soft or hard spring, respectively, as the curve is either bent tothe left or to the right, leading to the appearance of the jumpphenomenon. Figures 14, 15, and 16 show that the steady-state amplitude ๐‘Ž

    2is inversely proportional to ๐œ‡

    2, ๐œ”2and

    directly proportional to the external excitation ๐‘“2. Also, for

    decreasing ๐œ‡2, ๐œ”2the curve is bending to the left.

    4.2.3. Response Curve of Case 6. Figures 17, 18, 19, 20, 21,22, 23, 24, and 25 show that the frequency response curvesfor practical case stability, where ๐‘Ž

    1ฬธ= 0, ๐‘Ž2ฬธ= 0, and ๐‘Ž

    3ฬธ= 0.

  • 22 Mathematical Problems in Engineering

    โˆ’2 0 22

    4

    6

    8

    10

    1

    โˆ’2 0 2

    0.5

    1.5

    2.5

    3.5

    4.5

    0.01

    โˆ’2 0 2

    0.2

    0.6

    1

    1.4

    0.01

    a 3

    a 2

    a 1

    ๐œŽ1๐œŽ1

    ๐œŽ1

    ๐›ผ7 = 0.01๐›ฝ7 = 1

    ๐›พ7 = 1

    Figure 22: Effects of the nonlinear parameters (๐›ผ7, ๐›ฝ7, and ๐›พ

    7coupling terms).

    Figure 17 shows that the effects of the detuning parameter๐œŽ1on the amplitudes of the three modes. From this figure,

    we observe that these modes intersect, and for positive valueof the detuning parameter ๐œŽ

    1the amplitudes are stable. For

    negative value of the detuning parameter ๐œŽ1down to and

    including โˆ’0.5 the system becomes unstable.Figure 18 shows that the steady-state amplitudes of the

    three modes ๐‘Ž1, ๐‘Ž2, and ๐‘Ž

    3are directly proportional to

    the external excitation force ๐‘“1. Also, form this figure we

    show that the stability region is decreased for increasing ๐‘“1.

    Figures 19โ€“21 show that the steady-state amplitudes andstability of the threemodes ๐‘Ž

    1, ๐‘Ž2, and ๐‘Ž

    3are inversely propor-

    tional to the nonlinear parameters (๐›ผ1, ๐›ผ2, ๐›ผ8), (๐›ฝ1, ๐›ฝ2, ๐›ฝ8),

    and (๐›พ1, ๐›พ2, ๐›พ8), respectively.

    Figures 22โ€“24, show the effects of the nonlinear param-eters (๐›ผ

    7, ๐›ฝ7, ๐›พ7), (๐›ผ3, ๐›ฝ3, ๐›พ3), and (๐›ผ

    5,๐›ฝ5, ๐›พ5) on the steady-

    state amplitudes of the three modes. It is clear that thestability regions are increased for increasing these nonlinear

    parameters. For increasing value of linear viscous dampingcoefficients, we note that the steady-state amplitudes areincreasing or decreasing for the first, second, and thirdmodes, respectively, as shown in Figure 25. The region ofstability system is increased for decreasing value of dampingcoefficients.

    4.3. Comparison Study. In the previous work [11], the chaoticdynamics of a six-dimensional nonlinear system whichrepresents the averaged equation of a composite laminatedpiezoelectric rectangular plate subjected to the transverse, in-plane excitations and the excitation loaded by piezoelectriclayers are analyzed. The case of 1 : 2 : 4 internal resonances isconsidered.

    In our study, the nonlinear analysis and stability ofa composite laminated piezoelectric rectangular thin plateunder simultaneous external and parametric excitation forces

  • Mathematical Problems in Engineering 23

    โˆ’2 โˆ’1 0 1 20

    2

    4

    6

    8

    5

    10

    1.5

    โˆ’2 โˆ’1 0 1 20.5

    1.5

    2.5

    3.5

    5

    โˆ’1

    โˆ’1 โˆ’0.5 0 0.50

    0.5

    1

    1.5

    2

    5

    1.5-1

    ๐œŽ1

    ๐œŽ1๐œŽ1

    a 3

    a 2

    a 1

    ๐›ผ3 = โˆ’1

    ๐›ฝ3 = 10

    ๐›พ3 = 10

    Figure 23: Effects of the nonlinear parameters (๐›ผ3, ๐›ฝ3, and ๐›พ

    3coupling terms).

    are investigated.The second-order approximation is obtainedto consider the influence of the cubic terms on nonlin-ear dynamic characteristics of the composite laminatedpiezoelectric rectangular plate using the multiple scalemethod. All possible resonance cases are extracted at thisapproximation order. The case of 1 : 1 : 3 internal resonanceand primary resonance is considered. The stability of thesystem and the effects of different parameters on systembehavior have been studied using phase plane and frequencyresponse curves. The analytical results given by the methodof multiple time scale are verified by comparison with resultsfrom numerical integration of the modal equations. Reliabil-ity of the obtained results is verified by comparison betweenthe finite difference method (FDM) and Runge-Kuttamethod (RKM). Variation of the some parameters leads tomultivalued amplitudes and hence to jump phenomena. It isquite clear that some of the simultaneous resonance cases areundesirable in the design of such system. Such cases shouldbe avoided as working conditions for the system.

    5. Conclusions

    Multiple time scale perturbation method is applied to deter-mine second-order approximate solutions for rectangularsymmetric cross-ply laminated composite thin plate sub-jected to external and parametric excitations. Second-orderapproximate solutions are obtained to study the influenceof the cubic terms on nonlinear dynamic characteristics ofthe composite laminated piezoelectric rectangular plate. Allpossible resonance cases are extracted at this approximationorder. The study is focused on the case of 1 : 1 : 3 primary res-onance and internal resonance, whereฮฉ

    3โ‰… ๐œ”1, ๐œ”2โ‰… ๐œ”1, and

    ๐œ”3โ‰… 3๐œ”1.The analytical results given by themethod ofmulti-

    ple time scale are verified by comparison with results fromnumerical integration of the modal equations. Reliability ofthe obtained results is verified by comparison between thefinite difference method (FDM) and Runge-Kutta method(RKM). The stability of a composite laminated piezoelectricrectangular thin plate is investigated. The phase-plane

  • 24 Mathematical Problems in Engineering

    โˆ’2 โˆ’1 0 12

    3

    4

    5

    6

    40

    โˆ’2 โˆ’1 0 10.5

    1.5

    2.5

    3.5

    20

    โˆ’1 0 10.2

    0.6

    1

    40

    ๐œŽ1

    ๐œŽ1๐œŽ1

    a 3

    a 2a 1

    ๐›ผ5 = 20

    ๐›ฝ5 = 40

    ๐›พ5 = 20

    Figure 24: Effects of the nonlinear parameters (๐›ผ5, ๐›ฝ5, and ๐›พ

    5coupling terms).

    method and frequency response curves are applied to studythe stability of the system. From the previous study thefollowing may be concluded.

    (1) The simultaneous resonance case ฮฉ3โ‰… ๐œ”1, ๐œ”2โ‰… ๐œ”1,

    and ๐œ”3โ‰… 3๐œ”

    1is one of the worst case, and they

    should be avoided in design of such system.Of course,the excitation frequencyฮฉ

    3is out of control. But this

    case should be avoided through having ๐œ”2ฬธ= ๐œ”1or

    ๐œ”3ฬธ= 3๐œ”1.

    (2) A comparison between the solutions obtained numer-ically with that prediction from the multiple scalesshows an excellent agreement.

    (3) Reliability of the obtained results is verified by com-parison between the finite difference method (FDM)and Runge-Kutta method (RKM).

    (4) Variation of the parameters ๐œ‡1, ๐œ‡2, ๐›ผ7, ๐›ฝ8, ๐œ”1, ๐œ”2, ๐‘“1,

    ๐‘“2leads tomultivalued amplitudes and hence to jump

    phenomena.

    (5) For the first and second modes, the steady-stateamplitudes ๐‘Ž

    1and ๐‘Ž2are directly proportional to the

    excitation amplitude ๐‘“1and ๐‘“

    2and inversely propor-

    tional to the linear damping ๐œ‡1and ๐œ‡

    2, respectively.

    (6) The negative and positive values of nonlinear stiffness๐›ผ7, ๐›ฝ8produce either hard or soft spring, respectively,

    as the curve is either bent to the right or to the left.(7) The region of instability increase, which is undesir-

    able, for increasing excitation amplitudes ๐‘“1, ๐‘“2and

    for negative values of nonlinear stiffness ๐›ผ7, ๐›ฝ8.

    (8) The multivalued solutions are disappeared forincreasing linear damping coefficients ๐œ‡

    1, ๐œ‡2.

    (9) The region of stability increases, which is desirablefor decreasing excitation amplitude ๐‘“

    1, nonlinear

    parameters (๐›ผ1, ๐›ฝ1, ๐›พ1), (๐›ผ2, ๐›ฝ2, ๐›พ2), and for increasing

    nonlinear stiffness (๐›ผ7, ๐›ฝ7, ๐›พ7).

    (10) The steady-state amplitudes of the three modes ๐‘Ž1,

    ๐‘Ž2, and ๐‘Ž

    3are directly proportional to the exci-

    tation amplitude ๐‘“1and inversely proportional to

  • Mathematical Problems in Engineering 25

    โˆ’1 0 13

    4

    5

    6

    0.5

    0.2

    โˆ’1 0 1

    0.5

    1.5

    2.5

    0.5

    0.2

    โˆ’2 โˆ’1 0 1

    0.4

    0.8

    1.2

    1.6

    0.5

    0.2

    ๐œŽ1

    ๐œŽ1๐œŽ1

    a 3

    a 2

    a 1

    ๐œ‡1 = 1.2

    ๐œ‡2 = 1.2

    ๐œ‡3 = 1.2

    Figure 25: Effects of the linear damping coefficients.

    the nonlinear parameters (๐›ผ1, ๐›ผ2, ๐›ผ8), (๐›ฝ1, ๐›ฝ2, ๐›ฝ8), and

    (๐›พ1, ๐›พ2, ๐›พ8), respectively.

    For further work, we intend to extend our work to explorethe modeling formulation by investigating the role staticloading (in addition to the dynamic component).

    Acknowledgment

    The authors would like to thank the anonymous reviewers fortheir valuable comments and suggestions for improving thequality of this paper.

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