Publication:
Non-linear blow-up problems for systems of ODEs and PDEs: Non-local transformations, numerical and exact solutions

Дата
2019
Авторы
Shingareva, I. K.
Polyanin, A. D.
Journal Title
Journal ISSN
Volume Title
Издатель
Научные группы
Организационные подразделения
Организационная единица
Институт интеллектуальных кибернетических систем
Цель ИИКС и стратегия развития - это подготовка кадров, способных противостоять современным угрозам и вызовам, обладающих знаниями и компетенциями в области кибернетики, информационной и финансовой безопасности для решения задач разработки базового программного обеспечения, повышения защищенности критически важных информационных систем и противодействия отмыванию денег, полученных преступным путем, и финансированию терроризма.
Выпуск журнала
Аннотация
© 2019 Elsevier Ltd In Cauchy problems with blow-up solutions there exists a singular point whose position is unknown a priori (for this reason, the application of standard fixed-step numerical methods for solving such problems can lead to significant errors). In this paper, we describe a method for numerical integration of blow-up problems for non-linear systems of coupled ordinary differential equations of the first order (x m ) t ′ =f m (t,x 1 ,…,x n ), m=1,…,n, based on the introduction a new non-local independent variable ξ which is related to the original variables t and x 1 ,…,x n by the equation ξ t ′ =g(t,x 1 ,…,x n ,ξ). With a suitable choice of the regularizing function g, the proposed method leads to equivalent problems whose solutions are represented in parametric form and do not have blowing-up singular points; therefore, the transformed problems admit the use of standard numerical methods with a fixed stepsize in ξ. Several test problems are formulated for systems of ordinary differential equations that have monotonic and non-monotonic blow-up solutions, which are expressed in elementary functions. Comparison of exact and numerical solutions of test problems showed the high efficiency of numerical methods based on non-local transformations of a special kind. The qualitative features of numerical integration of blow-up problems for single ODEs of higher orders with the use of non-local transformations are described. The efficiency of various regularizing functions is compared. It is shown that non-local transformations in combination with the method of lines can be successfully used to integrate initial–boundary value problems, described by non-linear parabolic and hyperbolic PDEs, that have blow-up solutions. We consider test problems (admitting exact solutions) for nonlinear partial differential equations such as equations of the heat-conduction type and Klein–Gordon type equations, in which the blowing-up occurs both in an isolated point of space x=x ∗ , and on the entire range of variation of the space variable 0≤x≤1. The results of numerical integration of test problems, obtained when approximating PDEs by systems with a different number of coupled ODEs, are compared with exact solutions.
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Цитирование
Shingareva, I. K. Non-linear blow-up problems for systems of ODEs and PDEs: Non-local transformations, numerical and exact solutions / Shingareva, I.K., Polyanin, A.D. // International Journal of Non-Linear Mechanics. - 2019. - 10.1016/j.ijnonlinmec.2019.01.012
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