Paper Menu >>
Journal Menu >>
![]() Circuits and Systems, 2011, 2, 196-200 doi:10.4236/cs.2011.23028 Published Online July 2011 (http://www.SciRP.org/journal/cs) Copyright © 2011 SciRes. CS A Comparative Study of Analytical Solutions to the Coupled Van-der-Pol’s Non-linear Circuits Using the He’s Method (HPEM) and (BPES) Hüseyin Koçak1, Ahmet Yıldırım1, Dahong Zhang2, Karem Boubaker3, Syed Tauseef Mohyud-Din4 1Department of Mathematics, Ege University, Bornova–İzmir, Turkey 2Department of Physics, South China University, Guangzhou, China 3École Supérieure des Sciences et Techniques de Tunis, University of Tunis, Tunis, Tunisia 4Department of Basic Sciences, HITEC University, Taxila Cantt, Pakistan E-mail: [email protected], [email protected], Received October 6, 2010; revised May 13, 2011; accepted May 20, 2011 Abstract In this paper, the He’s parameter-expanding method (HPEM) and the 4q-Boubaker Polynomials Expansion Scheme (BPES) are used in order to obtain analytical solutions to the non-linear modified Van der Pol’s os- cillating circuit equation. The resolution protocols are applied to the ordinary Van der Pol equation, which annexed to conjoint delayed feedback and delay-related damping terms. The results are plotted, and com- pared with exact solutions proposed elsewhere, in order to evaluate accuracy. Keywords: Van-der-Pol’s Oscillating Circuit, Delayed Feedback, Damping, BPES, HPEM, Exact Solutions, Electrical Triode-Valve Circuit 1. Introduction Originally, the Van der Pol’s equation was associated, in the 1920s, with an electrical triode-valve circuit (Figure 1). In the last decades’ literature, it was the subject of several investigations due to the panoply of dynamical oddness as relaxation oscillations, elementary bifurca- tions, quasiperiodicity, and chaos. Its application has already reached nerve pulse propagation and electric potential evolution across neural membranes. Figure 1. Van der Pol oscillator synoptic scheme. The actual study tries to give a theoretical supply to the recent attempts to yield analytical solutions to this equation, like the studies of D. D. Ganji et al. [1,2] and A. Rajabi et al. [3] in the heat transfer domain, the investi- gations of L. Cveticanin [4] and J. H. He [5-7] on non- linear mechanics, fluid dynamics and oscillating systems modelling (Figure 2). Figure 2. A prototype of Van der Pol oscillating systems modelling (The two integrators are Trapezoidal-type 11 2 kkkk yhuu y ). ![]() H. KOÇAK ET AL. 197 Among the different formulations, the well-known standard boundary value-free Van der Pol oscillator problem (BVFP) is given by F. M. Atay [8] by the fol- lowing system (1): 2 ,, ,, 1 xt xtfxtxtxt fxt xt xtxtxtk xt (1) where is a positive parameter representing the delay, > 0 and is the feedback gain. k A simpler formulation is that of W. Jiang et al. [9]: 21 xt yt ytxtkf xtxtyt (2) In this study, an attempt to give analytical solution to the nonlinear second-order Van der Pol equation annexed to conjoint delayed feedback and delay-related damping terms as presented by A. Kimiaeifar et al. [10]: 2 0 0 1 00 00 xt yt ytxtxtytk xt xxH xx (3) 2. Analytical Solutions Derivation 2.1. The Enhanced He’s Parameter-Expanding Method (HPEM) Solution The resolution protocol based on the enhanced He’s pa- rameter-expanding method (HPEM) is founded on the infinite serial expansions: 0 0 n n n n n n xtx t xtx t (4a) Substituting these expansions in the main equation Equation (3) and processing with the standard perturba- tion method, it has been demonstrated [10] that a solu- tion of the kind: 0cosxt Ht (4b) where H , and are constant, gives: 2 111 32 ( )sin()( )cos() cos( )sin( ) cos() cos() sin()sin() 0 xt HtxtHt Htt kH t kH t .2. The Boubaker Polynomials Expansion y- nomials expansion scheme (BPES) [11-23]. The first step of this scheme starts by applying the (4c) with, as a final solution (Equation (4d)): 2 Scheme (BPES)-Related Solution The resolution protocol is based on the Boubaker pol expressions: 4 0 1λ 2kk k k 0 1 N x tBtr N (4e) where 4k B are 4k-order Boubaker polynom the normalized time ( theials, is 0,1t), k r are minimal po tege 4k B r, and sitive roots, 0 N is a prefixed in0 1.. kkN λ are u poing Consequently, it comes that: nknownnder real coefficients. 04 1 0 2d kk kk k yt xt λr Nt (5) The main advantage of these formulations (Equations (4) and (5)) is the fact of verifying the boundary conditions in d 1NBtr t stage of fact, due to the properties of the Boubaker polynomials [12-18], and since Equation (3), at the earliesresolution protocol. In 0 1..kN k rare the roots of k r 0 41.. kkN B, the following conditions stand : 0 0 0 01 0 4 1 0 00 10 d d10 d2 d N k tk Nkk kk k tt xt λAx N Btr xt r tN t (6) By introducing expressions (4) and (6) in the system (3), and by majoring and integrating along the interval 0,1 , x t is confined, through the coefficients 0 1.. kkN , to be a weak solution of the system: 000 0 2 111 2 14 2 0 14 0 1 4 0 1 4 0 00 0 1 0 dd d dd d d d NNN kk kkkkkkk kkk kk k kk k kkk kkk N k k rM rPQkR Btr Mt t Btr Pt t QBtrt RBtrt Nx NH (7) 4224 22 2 26 336 3636 cos kk kkk xt Ht k (4d) Copyright © 2011 SciRes. CS ![]() 198 The set of solutions H. KOÇAK ET AL. 0 1, , ˆkkN is the one which mini mizes, for given values of and the Minimum Square function (8) (9) The condition expressed by Equation (9) ensures a non-zero solution to the system (8). The convergence of the algorithm is tested relatively to increasing values of e correspondent solutions are represented in Figure 3 for the data gathered in Table 1, solutions given by F. M. Atay [8] and A. Kimiaeifar et al yi k , MS k : 000 2 2 1 , ˆˆˆ MS NNN kkk k k rM rPQkR 11 kk k kk k kk under the intrinsic condition: 0 0 1 ˆ N k k NH 0 N. Th along with the exact . [10]. It is noted that F. M. Atay [8] demonstrated that the presence of delay can change the amplitude of limit cycle oscillations, or suppress them altogether through derivative-like effects, while A. Kimiaeifar et al. [10] elded a highly accurate solution to the same classical Van der Pol equation with delayed feedback and a modi- fied equation where a delayed term provides the damping. The features of the proposed solutions [8-10] (namely behavior at starting phase, first derivatives at limit time, etc.) are concordant with the actually proposed results. Figure 3. Analytical solutions plots. Table 1. Solution parameters values. Parameter Value 0.1 k −1.0 1.0 0 x 2.75 0 x 0.0 0 N Figure 4. Mean absolute error versus N0. 3. Results and Discussions The results show a good agreement between the pro- posed analytical solutions (Figure 3) and those of the recent studies published elsewhere. The mean absolute error (for) was less than 3.33% (Figure 4). The convehe BPES-related protocol has been recorded fs of superior to 30. 4. Conclusions In this paper, we have used the enhanced He’s parame ter-expanding Method (HPEM) along with thBoubaker olynomr to ob- c periodical solutions. acceptable agreement into an istic nonlinear system. This simple duction is carried out through the 030N rgence of t or the value0 N - e ials Expansion Scheme (BPES) in ordeP tain the Van der Pol’s characteristi The obtained solutions were in with those obtained from values of similarly performed methods. The typical periodical aspect of the oscillations, already yielded [2,10,24-27] by the enhanced He’s pa- rameter-expanding method (HPEM) could be reproduced using a simple and convergent polynomial approxima- tion. This method was based on an original protocol hich reduces the stochastic nonlinear systemw equivalent determin nd controllable rea verification of the initial conditions, in the solution basic expression, prime to launching the resolution process. The results show that the methods are very promising ones and might find wide applications, particularly when exact solutions expressions are difficult to establish [28-34]. 5. References [1] D. D. Ganji and A. Rajabi, “Assessment of Homotopy Perturbation and Perturbation Methods in Heat Transfer Radiation Equations,” International Communications in 31 0.0 Copyright © 2011 SciRes. CS ![]() H. KOÇAK ET AL. 199 Heat and Mass Transfer, Vol. 33, No. 3, 2006, pp. 391- 400. doi:10.1016/j.icheatmasstransfer.2005.11.001 [2] D. D. Ganji and A. Sadighi, “Application of He’s Homo- topy-Perturbation Method to Nonlinear Coupled Systems of Reaction-Diffusion Equations,” International Journal of Nonlinear Sciences and Numerical Simulation, Vol. 7, No. 4, 2006, pp. 411-418. doi:10.1515/IJNSNS.2006.7.4.411 [3] A. Rajabi, D. D. Ganji and H. Taherian, “Application of Homotopy Perturbation Method in Nonlinear Heat Con- duction and Co Vol. 360, No. nvection Equations,” Physics Letters A, 4-5, 2007, pp. 570-573. doi:10.1016/j.physleta.2006.08.079 [4] L. Cveticanin, “Homotopy-Perturbation Method for Pure Nonlinear Differential Equation,” Chaos, Solitons & Fractals, Vol. 30, No. 5, 2006, pp. 1221-1230. doi:10.1016/j.chaos.2005.08.180 [5] J. H. He, “Homotopy Perturbation Method for Bifurca- tion of Nonlinear Problems,” International Journal of Nonlinear Sciences and Numerical Simulation, Vol. 6, No. 2, 2005, pp. 207-208. [6] J. H. He, “Homotopy Perturbation Method For Solving Boundary Value Problems,” Physic No. 1-2, 2006, pp. 87-88. s Letters A, Vol. 350, [7] J. H. He, “Limit Cycle and Bifurcation of Nonlinear Problems,” Chaos, Solitons & Fractals, Vol. 26, No. 3, 2005, pp. 827-833. doi:10.1016/j.chaos.2005.03.007 [8] F. M. Atay, “Van der Pol’s Oscillator under Delayed Feedback,” Journal of Sound and Vibration, Vol. 218, No. 2, 1998, pp. 333-339. doi:10.1006/jsvi.1998.1843 [9] W. Jiang and J. Wei, “Bifurcation Analysis in Van der Pol’s Oscillator with Delayed Feedback,” Journal of Computational and Applied Mathematics, Vol. 213, No. 2 2008, pp. 604-615. , doi:10.1016/j.cam.2007.01.041 [10] A. Kimiaeifar, A. R. Saidi, A. R. Sohouli and D. D. Ganji, “Analysis of Modified Vander Pol’s Oscillator Using He’s Parameter-Expanding Methods,” Current Applied Physics, Vol. 10, No. 1, 2010, pp. 279-283. doi:10.1016/j.cap.2009.06.006 [11] J. Ghanouchi, H. Labiadh and K. Boubaker, “An Attempt to Solve the Heat Transfert Equation in a Model of Pyro- lysis Spray Using 4q-Order m-Boubaker Polynomials,” International Journal of Heat & Technology, Vol. 26, No. 1, 2008, pp. 49-53. [12] O. B. Awojoyogbe and K. Boubaker, “A Solution to Bloch NMR Flow Equations for the Analysis of Homo- dynamic Functions of Blood Flow System Using m-Bou- baker Polynomials,” Current Applied Physics, Vol. 9, No. 3, 2009, pp. 278-288. doi:10.1016/j.cap.2008.01.019 [13] H. Labiadh and K. Boubaker, “A Sturm-Liouville Shaped ials Solution to Heat Equation for ated mials B_4q(X) (Named e and F. Moses, Characteristic Differential Equation As a Guide to Estab- lish a Quasi-Polynomial Expression to the Boubaker Po- lynomials,” Differential Equations and Control Processes, Vol. 2, No. 2, 2007, pp. 117-133. [14] S. Slama, J. Bessrour, M. Bouhafs and K. B. Ben Mah- moud, “Numerical Heat Transfer, Part A: Application,” An International Journal of Computation and Methodol- ogy, Vol. 48, No. 6, 2005, pp. 401-404. [15] S. Slama, M. Bouhafs and K. B. Ben Mahmoud, “A Boubaker Polynom Monitoring A3 Point Evolution During Resistance Spot Welding,” International Journal of Heat and Technology, Vol. 26, No. 2, 2008, pp. 141-146. [16] H. Rahmanov, “Triangle Read by Rows: Row n Gives Coefficients of Boubaker Polynomial B_n(x), Calcul for X = 2cos(t), Centered by Adding –2cos(nt), Then Di- vided by 4, in Order of Decreasing Exponents,” OEIS (Encyclopedia of Integer Sequences), A160242. [17] H. Rahmanov, “Triangle Read by Rows: Row n Gives Values of the 4q-28Boubaker Polyno after Boubaker Boubaker (1897-1966)), Calculated for X = 1 (or –1),” OEIS (Encyclopedia of Integer Sequences), A162180. [18] S. Tabatabaei, T. Zhao, O. Awojoyogb “Cut-Off Cooling Velocity Profiling Inside a Keyhole Model Using the Boubaker Polynomials Expansion Scheme,” Heat and Mass Transfer, Vol. 45, No. 10, 2009, pp. 1247-1255. doi:10.1007/s00231-009-0493-x [19] S. Fridjine and M. Amlouk, “A New Parameter: An ABACUS for Optimizig Functional Materials Using the Boubaker Polynomials Expansion Scheme,” Modern Physics Letters B, Vol. 23, No. 17, 2009, pp. 2179-2182. doi:10.1142/S0217984909020321 [20] A. Belhadj, J. Bessrour, M. Bouhafs and L. Barrallier, “Experimental and Theoretical Cooling Velocity Profile Inside Laser Welded Metals Using Keyhole Approxima- tion and Boubaker Polynomials Expansion,” Journal of Thermal Analysis and Calorimetry, Vol. 97, No. 3, 2009, pp. 911-920. doi:10.1007/s10973-009-0094-4 [21] A. Belhadj, O. Onyango and N. Rozibaeva, “Boubaker Polynomials Expansion Scheme-Related Heat Transfer Investigation Inside Keyhole Model,” Journal of Ther- mophysics Heat Transfer, Vol. 23, No. 6, 2009, pp. 639- 642. [22] A. Chaouachi, K. Boubaker, M. Amlouk and H. Bou- zouita, “Enhancement of Pyrolysis Spray Disposal Per- formance Using Thermal Time-Response to Precursor Uniform Deposition,” The European Physical Journal - Applied Physics, Vol. 37, No. 1, 2007, pp. 105-109. doi:10.1051/epjap:2007005 [23] D. H. Zhang and F. W. Li, “A Boubaker Polynomials Expansion Scheme BPES-Related Analytical Solution to Williams-Brinkmann Stagnation Point Flow Equation at a Blunt Body,” Journal of Engineering Physics and Ther- mophysics, Vol. 84, No. 3, 2009, pp. 618-623. [24] Z. L. Tao, “Frequency–Amplitude Relationship of Non- linear Oscillators by He’s Parameter-Expanding Me- thod,” Chaos, Solitons & Fractals, Vol. 41, No. 2, 2009, pp. 642-645. doi:10.1016/j.chaos.2008.02.036 [25] L. Xu, “He’s Parameter-Expanding Methods for Strongly Nonlinear Oscillators,” Journal of Computational and Applied Mathematics, Vol. 207, No. 1, 2007, pp. 148-154. doi:10.1016/j.cam.2006.07.020 [26] D. D. Ganji, M. Rafei, A. Sadighi and Z. Z. Ganji, “A Comparative Comparison of He’s Method with Perturba- Copyright © 2011 SciRes. CS ![]() H. KOÇAK ET AL. Copyright © 2011 SciRes. CS 200 s for Nonlinear Vibrations s, Vol. 90, tion and Numerical Method Equations,” International Journal of Nonlinear Dynamics in Engineering and Sciences, Vol. 1, No. 1, 2009, pp. 1- 20. [27] J. H. He, “Determination of Limit Cycles for Strongly Nonlinear Oscillators,” Physical Review Letter No. 17, 2003, pp. 1-11. doi:10.1103/PhysRevLett.90.174301 [28] Z. M. Odibat and S. Momani, “Application of Variational Iteration Method to Nonlinear Differential Equations of Fractional Order,” International Journal of Nonlinear Sciences and Numerical Simulation, Vol. 7, No. 1, 2006, pp. 27-34. doi:10.1515/IJNSNS.2006.7.1.27 [29] E. Yusufoglu, “Variational Iteration Method for Con- struction of Some Compact and Non Compact Structures of Klein-Gordon Equations,” International Journal of Nonlinear Sciences and Numerical Simulation, Vol. 8, No. 2, 2007, pp. 152-158. [30] M. D’Acunto, “Self-Excited Systems: Analytical Deter- mination of Limit Cycles,” Chaos, Solitons & Fractals, Vol. 30, No. 3, 2006, pp. 719-724. doi:10.1016/j.chaos.2006.03.070 [31] J. K. Hale, “Averaging Methods for Differential Equa- tions with Retarded Arguments and a Small Parameter,” Journal of Differential Equations, Vol. 2, No. 1, 1966, pp. 57-73. doi:10.1016/0022-0396(66)90063-5 Dynamics in Engi- 1, 2009, pp. 59-66. [32] A. Golbabai and D. Ahmadian, “Homotopy Pade Method for Solving Linear and Nonlinear Integral Equations,” International Journal of Nonlinear neering and Sciences, Vol. 1, No. [33] J. H. He, “Some Asymptotic Methods for Strongly Non- linear Equations,” International Journal of Modern Physics B, Vol. 20, No. 10, 2006, pp. 1141-1199. doi:10.1142/S0217979206033796 [34] J. H. He, “Book Keeping Parameter in Perturbation Me- thods,” International Journal of Nonlinear Sciences and Numerical Simulation, Vol. 2, No. 3, 2001, pp. 257-264. |






