M. P. Galanin (Bauman Moscow State Technical University/Keldysh Institute of Applied Mathematics of the Russian Academy of Scienсes) :
Articles:
519.6 Методы численного решения дифференциального уравнения смешанного типа в неограниченной области
Galanin M. P. (Bauman Moscow State Technical University/Keldysh Institute of Applied Mathematics of the Russian Academy of Scienсes), Sorokin F. D. (Bauman Moscow State Technical University/Keldysh Institute of Applied Mathematics of the Russian Academy of Scienсes), Ukhova A. R. (Bauman Moscow State Technical University)
doi: 10.18698/2309-3684-2021-1-91109
Разработаны методы численного решения задачи для уравнения смешанного типа в неограниченной области в случае, когда решение удовлетворяет уравнению теплопроводности в ограниченной области и уравнению Лапласа в оставшейся части пространства. Предложен способ задания искусственных граничных условий, позволяющий проводить расчёты в ограниченной области. Построен итерационный алгоритм нахождения численного решения в ограниченной области, такой что численное решение сходится к проекции точного решения на ограниченную область. Исследована скорость сходимости итерационного алгоритма. Задача решена в одномерном плоском, в цилиндрически и сферически симметричных случаях. Приведены примеры решений.
Галанин М.П., Сорокин Д.Л., Ухова А.Р. Методы численного решения дифференциального уравнения смешанного типа в неограниченной области. Математическое моделирование и численные методы, 2021, № 1, с. 91–109.
519.63 Development and testing for methods of solving stiff ordinary differential equations
Galanin M. P. (Bauman Moscow State Technical University/Keldysh Institute of Applied Mathematics of the Russian Academy of Scienсes), Khodzhaeva S. R. (Bauman Moscow State Technical University)
doi: 10.18698/2309-3684-2014-4-95119
The paper is aimed at research of the (m,k)-method, CROS, finite superelement method and 4-stage explicit Runge–Kutta method for solving stiff systems of ordinary differential equations. Analysis of tests results showed that the best choice for systems with high stiffness is CROS. The finite superelement method is the «precise» method for solving linear systems of ordinary differential equations, the best supporting method for its implementation is (4,2)-method. The variation of the finite superelement method has been built and tested for solving nonlinear problems, this method proved to be unsuitable for problems with high stiffness.
Galanin M., Khodzhaeva S. Development and testing for methods of solving stiff ordinary differential equations. Маthematical Modeling and Coтputational Methods, 2014, №4 (4), pp. 95-119
519.6 Numerical solution of equations of mixed type in unlimited region on a plane
Galanin M. P. (Bauman Moscow State Technical University/Keldysh Institute of Applied Mathematics of the Russian Academy of Scienсes), Ukhova A. R. (Bauman Moscow State Technical University)
doi: 10.18698/2309-3684-2023-3-105124
The purpose of the work is to build and implement an algorithm for finding a numerical solution to a problem for mixed-type equations in an unlimited region. In this case problems are considered in which the process under study is described in some limited area by the thermal conductivity equation or wave equation, and outside it by the Laplace equation. The necessary additional conditions at zero, at infinity and the conditions for conjunction at the border of the inner region are set. There is described an algorithm for finding a numerical solution to a problem with a wave equation in a limited region in one-dimensional and two-dimensional cases, problems with a thermal conductivity equation or a wave equation in a two-dimensional case. Difference schemes are built by the integro–interpolation method. The task is solved in a limited area. Nonlocal boundary conditions are set on its border so the solution of task in limited area coincides with projection of problem in unlimited area. In this case, an artificial boundary is introduced for the solution in the part of the region in which the process is described by the Laplace equation. An iterative algorithm and an algorithm with a non-local boundary condition are built. The results of calculations for examples in various fields are presented.
Галанин М.П., Ухова А.Р. Численное решение уравнений смешанного типа в неограниченной области на плоскости. Математическое моделирование и численные методы, 2023, № 3, с. 105–124.