Home A semi-analytic method for fractional-order ordinary differential equations: Testing results
Article
Licensed
Unlicensed Requires Authentication

A semi-analytic method for fractional-order ordinary differential equations: Testing results

  • Sergiy Reutskiy EMAIL logo and Zhuo-Jia Fu
Published/Copyright: February 9, 2019

Abstract

The paper presents the testing results of a semi-analytic collocation method, using five benchmark problems published in a paper by Xue and Bai in Fract. Calc. Appl. Anal., Vol. 20, No 5 (2017), pp. 1305–1312, DOI: 10.1515/fca-2017-0068.

5 Appendix

  1. Let us find the Caputo derivative Dtαm], 0 < α ≤ 1 of the discontinuous function

    Ψmt=0,0ttmttmp,tm<t,DtαΨmt=def1Γ1α0tΨm1τtταdτ.

    Using

    Ψm1t=0,0ttmpttmp1,tm<t,

    we get:

    DtαΨmt=def0,0ttm<2,pΓ1αtmtτtmp1tταdτ,tm<t2,pΓ1αtmtτtmp1tταdτ using τ=ζ+tm=pΓ1α0ttmζ+tmtmp1tζtmαdζ=pΓ1α0ttmζp1ttmζαdζ=ttm=spΓ1α0sζp1sζαdζ=pΓ1α0sζp1sζ1α1dζ=pΓ1αΓpΓ1αΓp+1αspα=pΓpΓp+1αspα=Γp+1Γp+1αspα=Γp+1Γp+1αttmpα.

    Here we use the Euler integral:

    0tζp1tζq1dζ=ΓpΓqΓp+qtp+q1.

    Finally, we obtain:

    DtαΨmt=0,0ttm<2,Γp+1Γp+1αttmpα,tm<t2.
  2. Dt2ut=AtutDt0.5ututt2+e2t.

    Let us consider u,v=Dt0.5ut, and w = ut(t) as independent variables,

    Dt2u=Atuvw2+e2t

    Suppose that u0, v0, w0 are given functions of t which are the initial approximations of the corresponding exact values. Then we have the following relations:

    u=u0+(uu0)=u0+δu,v=v0+(vv0)=v0+δv,w=w0+(ww0)=w0+δw.

    Assuming that δu, δv, δw are small values, the equation can be linearized by the following way:

    uv=u0+δuv0+δvv0δu+u0δv+u0v0=v0(uu0)+u0(vv0)+u0v0=v0u+u0vu0v0,w2=w0+δw2w02+2w0δw=w02+2w0(ww0)=2w0ww02.

    As a result, we get the linear equation with respect to u, v, w:

    Dt2u=Atv0u+u0vu0v02w0ww02+e2t,Dt2u=Atv0tu+Atu0tv2w0tw+e2tAtu0tv0tw02t.

    Returning to the old notations, we get the linear equation

    Dt2u=Atv0tu+Atu0tDt0.5u2w0tu1+e2tAtu0tv0tw02t,

    or

    DtνuDt2u=Btu+CtDt0.5u+Etu1+FtDtνu=Btu+CtDtν1u+Etu1+Ft,

    where

    Bt=Atv0t=AtDt0.5u0,Ct=Atu0t,Et=2w0t=2u01t,Ft=e2tAtu0tDt0.5u0u01t2.
  3. Using the quasilinearization procedure, we can write:

    wsvsw0sv0s+sw0s1v0sww0+sw0sv0s1vv0=sw0s1v0sw+sw0sv0s1v+12sw0sv0s.

    So, the right hand side of the equation (65) can be written in the form:

    Avsws+fItAsw0s1v0sw+Asw0sv0s1v+A12sw0sv0s+fIt=Ptw+Rtv+Ft,

    where

    Pt=Asw0s1v0s,Rt=Asw0sv0s1,Ft=A12sw0sv0s+fIt.

Acknowledgements

The work described in this paper was supported by the National Science Fund of China (Grant Nos. 11772119,11572111), the Foundation for Open Project of State Key Laboratory of Structural Analysis for Industrial Equipment (Grant No. GZ1707), the Sino-Ukraine Science and Technology Cooperation Project (Grant No. CU02-18), the Fundamental Research Funds for the Central Universities (Grant No. 2016B06214), Alexander von Humboldt Research Fellowship (ID: 1195938) and Qing Lan Project.

References

[1] R. Bellman, R.E. Kalaba, Quasilinearization and Nonlinear Boundary Value Problems. Elsevier, New York (1965).Search in Google Scholar

[2] K. Diethelm, The Analysis of Fractional Differential Equations: An Application-Oriented Exposition Using Differential Operators of Caputo Type. Springer, Berlin (2010).10.1007/978-3-642-14574-2Search in Google Scholar

[3] Z.J. Fu, Q. Xi, W. Chen, A.H.D. Cheng, A boundary-type meshless solver for transient heat conduction analysis of slender functionally graded materials with exponential variations. Comput. Math. Appl. 76, No 6 (2018), 760–773.10.1016/j.camwa.2018.05.017Search in Google Scholar

[4] Z.J. Fu, L.W. Yang, H.Q. Zhu, W.Z. Xu, A semi-analytical collocation Trefftz scheme for solving multi-term time fractional diffusion-wave equations. Eng. Anal. Bound. Elem. 98, No 6 (2019), 137–146.10.1016/j.enganabound.2018.09.017Search in Google Scholar

[5] P. Mokhtary, F. Ghoreishi, H.M. Srivastava, The Müntz-Legendre Tau method for fractional differential equations. Appl. Math Model. 40, No 7 (2016), 671–684.10.1016/j.apm.2015.06.014Search in Google Scholar

[6] I. Podlubny, Fractional Differential Equations. Academic Press, San Diego (1999).Search in Google Scholar

[7] S.Y. Reutskiy, The backward substitution method for multipoint problems with linear Volterra-Fredholm integro-differential equations of the neutral type. J. Comp. Appl. Math. 296, No 10 (2016), 724–738.10.1016/j.cam.2015.10.013Search in Google Scholar

[8] S.Y. Reutskiy, A new semi-analytical collocation method for solving multi-term fractional partial differential equations with time variable coefficients. Appl. Math. Modell. 45, No 5 (2017), 238–254.10.1016/j.apm.2016.12.029Search in Google Scholar

[9] D. Xue, L. Bai, Benchmark problems for Caputo fractional-order ordinary differential equations. Fract. Calc. Appl. Anal. 20, No 5 (2017), 1305–1312; 10.1515/fca-2017-0068; https://www.degruyter.com/view/j/fca.2017.20.issue-5/issue-files/fca.2017.20.issue-5.xml.Search in Google Scholar

Received: 2017-12-26
Published Online: 2019-02-09
Published in Print: 2018-12-19

© 2018 Diogenes Co., Sofia

Downloaded on 16.11.2025 from https://www.degruyterbrill.com/document/doi/10.1515/fca-2018-0084/pdf?lang=en
Scroll to top button