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arXiv · 2210.00467

Numerical analysis for coagulation-fragmentation equations with singular rates

Sanjiv Kumar Bariwal·Prasanta Kumar Barik·Ankik Kumar Giri·Rajesh Kumar
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Abstract

This article deals with the convergence of finite volume scheme (FVS) for solving coagulation and multiple fragmentation equations having locally bounded coagulation kernel but singularity near the origin due to fragmentation rates. Thanks to the Dunford-Pettis and De La Vall$\acute{e}$e-Poussin theorems which allow us to have the convergence of numerically truncated solution towards a weak solution of the continuous model using a weak $L^1$ compactness argument. A suitable stable condition on time step is taken to achieve the result. Furthermore, when kernels are in $W^{1,\infty}_{loc}$ space, first order error approximation is demonstrated for a uniform mesh. It is numerically validated by attempting several test problems.

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Sanjiv Kumar Bariwal, Prasanta Kumar Barik, Ankik Kumar Giri, Rajesh Kumar. 2022-10-02. Numerical analysis for coagulation-fragmentation equations with singular rates. https://arxiv.org/abs/2210.00467

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