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Title: A Nonoscillatory Second-Order Time-Stepping Procedure for Reaction-Diffusion Equations
After a theory of morphogenesis in chemical cells was introduced in the 1950s, much attention had been devoted to the numerical solution of reaction-diffusion (RD) partial differential equations (PDEs). The Crank–Nicolson (CN) method has been a common second-order time-stepping procedure. However, the CN method may introduce spurious oscillations for nonsmooth data unless the time step size is sufficiently small. This article studies a nonoscillatory second-order time-stepping procedure for RD equations, called a variable- θ method , as a perturbation of the CN method. In each time level, the new method detects points of potential oscillations to implicitly resolve the solution there. The proposed time-stepping procedure is nonoscillatory and of a second-order temporal accuracy. Various examples are given to show effectiveness of the method. The article also performs a sensitivity analysis for the numerical solution of biological pattern forming models to conclude that the numerical solution is much more sensitive to the spatial mesh resolution than the temporal one. As the spatial resolution becomes higher for an improved accuracy, the CN method may produce spurious oscillations, while the proposed method results in stable solutions.  more » « less
Award ID(s):
1714157
PAR ID:
10157131
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Complexity
Volume:
2020
ISSN:
1076-2787
Page Range / eLocation ID:
1 to 15
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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