Stability of stationary solutions of singular systems of balance laws

Nicolas Seguin

doi:10.5802/cml.52

Well-Balanced High-Order Discontinuous Galerkin Methods for Systems of Balance Laws

Mathematics ◽

10.3390/math10010015 ◽

2021 ◽

Vol 10 (1) ◽

pp. 15

Author(s):

Ernesto Guerrero Fernández ◽

Cipriano Escalante ◽

Manuel J. Castro Díaz

Keyword(s):

Numerical Method ◽

Discontinuous Galerkin ◽

Stationary Solutions ◽

High Order ◽

General Strategy ◽

Balance Laws ◽

Smooth Solutions ◽

Systems Of Balance Laws ◽

Spurious Oscillations ◽

Time Marching

This work introduces a general strategy to develop well-balanced high-order Discontinuous Galerkin (DG) numerical schemes for systems of balance laws. The essence of our approach is a local projection step that guarantees the exactly well-balanced character of the resulting numerical method for smooth stationary solutions. The strategy can be adapted to some well-known different time marching DG discretisations. Particularly, in this article, Runge–Kutta DG and ADER DG methods are studied. Additionally, a limiting procedure based on a modified WENO approach is described to deal with the spurious oscillations generated in the presence of non-smooth solutions, keeping the well-balanced properties of the scheme intact. The resulting numerical method is then exactly well-balanced and high-order in space and time for smooth solutions. Finally, some numerical results are depicted using different systems of balance laws to show the performance of the introduced numerical strategy.

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Collocation Methods for High-Order Well-Balanced Methods for Systems of Balance Laws

Mathematics ◽

10.3390/math9151799 ◽

2021 ◽

Vol 9 (15) ◽

pp. 1799

Author(s):

Irene Gómez-Bueno ◽

Manuel Jesús Castro Díaz ◽

Carlos Parés ◽

Giovanni Russo

Keyword(s):

High Order ◽

Collocation Methods ◽

Quadrature Formulas ◽

Balance Laws ◽

Source Terms ◽

Time Step ◽

Systems Of Balance Laws ◽

Reconstruction Operator ◽

Non Linear ◽

Linear Problems

In some previous works, two of the authors introduced a technique to design high-order numerical methods for one-dimensional balance laws that preserve all their stationary solutions. The basis of these methods is a well-balanced reconstruction operator. Moreover, they introduced a procedure to modify any standard reconstruction operator, like MUSCL, ENO, CWENO, etc., in order to be well-balanced. This strategy involves a non-linear problem at every cell at every time step that consists in finding the stationary solution whose average is the given cell value. In a recent paper, a fully well-balanced method is presented where the non-linear problems to be solved in the reconstruction procedure are interpreted as control problems. The goal of this paper is to introduce a new technique to solve these local non-linear problems based on the application of the collocation RK methods. Special care is put to analyze the effects of computing the averages and the source terms using quadrature formulas. A general technique which allows us to deal with resonant problems is also introduced. To check the efficiency of the methods and their well-balance property, they have been applied to a number of tests, ranging from easy academic systems of balance laws consisting of Burgers equation with some non-linear source terms to the shallow water equations—without and with Manning friction—or Euler equations of gas dynamics with gravity effects.

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