Numerical solution of a weakly singular integral equation by the method of orthogonal polynomials

Abstract

A scheme is constructed for the numerical solution of a singular integral equation with a logarithmic kernel by the method of orthogonal polynomials. The proposed schemes for an approximate solution of the problem are based on the representation of the solution function in the form of a linear combination of the Chebyshev orthogonal polynomials and spectral relations that allows to obtain simple analytical expressions for the singular component of the equation. The expansion coefficients of the solution in terms of the Chebyshev polynomial basis are calculated by solving a system of linear algebraic equations. The results of numerical experiments show that on a grid of 20 –30 points, the error of the approximate solution reaches the minimum limit due to the error in representing real floating-point numbers.

Author Biography

Sergei M. Sheshko, Belarusian State University, 4 Niezaliežnasci Avenue, Minsk 220030, Belarus

senior lecturer at the department of digital economy, faculty of economics

References

  1. Panasyuk VV, Savruk MP, Nazarchuk ZT. Metod singulyarnykh integral’nykh uravnenii v dvumernykh zadachakh difraktsii [The method of singular integral equations in two-dimensional diffraction problems]. Kyiv: Naukova dumka; 1984. 344 p. Russian.
  2. Rasolko GA. Numerical solution of singular integro-differential Prandtl equation by the method of orthogonal polynomials. Journal of the Belarusian State University. Mathematics and Informatics. 2018;3:68–74. Russian.
  3. Rasolko GA. To the numerical solution of singular integro-differential Prandtl equation by the method of orthogonal polynomials. Journal of the Belarusian State University. Mathematics and Informatics. 2019;1:58–68. Russian.
  4. Rasolko GA, Sheshko SM, Sheshko MA. [Numerical method for some singular integro-differential equations]. Differentsial’nye uravneniya. 2019;55(9):1285–1292. Russian.
  5. Rasolko GA, Sheshko SM. An approximate solution of one singular integro-differential equation using the method of orthogonal polynomials. Journal of the Belarusian State University. Mathematics and Informatics. 2020;2:86–96. Russian.
  6. Muskhelishvili NI. Singulyarnye integral’nye uravneniya [Singular integral equations]. 3rd edition. Moscow: Nauka; 1968. 513 p. Russian.
  7. Pashkovskii S. Vychislitel’nye primeneniya mnogochlenov i ryadov Chebysheva [Computational applications of polynomials and Chebyshev series]. Moscow: Nauka; 1983. 384 p. Russian.
  8. Kolmogorov AN, Fomin SV. Elementy teorii funktsii i funktsional’nogo analiza [Elements of the theory of functions and functional analysis]. 6th edition. Moscow: Nauka; 1989. 624 p. Russian.
Published
2021-11-19
Keywords: integro-differential equation, numerical solution, method of orthogonal polynomials
Supporting Agencies The author would like to thank to the scientific advisor G. A. Rasolko for setting the problem and valuable comments.
How to Cite
Sheshko, S. M. (2021). Numerical solution of a weakly singular integral equation by the method of orthogonal polynomials. Journal of the Belarusian State University. Mathematics and Informatics, 3, 98-103. https://doi.org/10.33581/2520-6508-2021-3-98-103