On the location of straight discontinuity intervals of arbitrary sectionally analytic functions by using complex path-independent integrals

Abstract

The classical method of locating zeros and poles of analytic and meromorphic functions in the complex plane via the evaluation of complex path-independent integrals on closed contours surrounding the sought zeros and poles is generalized to become applicable (for the first time) to the location of straight discontinuity intervals of completely general sectionally analytic functions possessing such an interval. Such is the case e.g. in crack problems in plane elasticity or in airfoils in plane fluid dynamics. This generalization makes use of appropriate or arbitrary quadrature rules and, in this way, it leads to a completely numerical method. The method is illustrated in the case of a simple sectionally analytic function, where the classical Chebyshev and Legendre polynomials are used and numerical results are presented. Possible generalizations of the present results are also reported in brief and are strongly expected in future.