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Isotropic artificial dissipation is added to the Navier‐Stokes equations along with a correction term which cancels the artificial dissipation term in the limit when the mesh size is zero. For a finite mesh size, the correction term replaces the artificial viscosity terms with hyperviscosity terms, i.e., with an artificial dissipation which depends on the fourth derivatives of the velocity. Hyperviscosity more effectively suppresses the higher wave number modes and has a smaller effect on the inertial modes of the flow field than does artificial viscosity. This scheme is implemented using the finite element method and therefore the required amount of dissipation is determined by analysing the discretization on a finite element. The scheme is used to simulate the flow in a driven cavity and over a backward facing step and the results are compared to existing results for these cases.

This study aims to apply a numerical meshless method, namely, the boundary knot method (BKM) combined with the meshless analog equation method (MAEM) in space and use a semi-implicit scheme in time for finding a new numerical solution of the advection–reaction–diffusion and reaction–diffusion systems in two-dimensional spaces, which arise in biology.

First, the BKM is applied to approximate the spatial variables of the studied mathematical models. Then, this study derives fully discrete scheme of the studied models using a semi-implicit scheme based on Crank–Nicolson idea, which gives a linear system of algebraic equations with a non-square matrix per time step that is solved by the singular value decomposition. The proposed approach approximates the solution of a given partial differential equation using particular and homogeneous solutions and without considering the fundamental solutions of the proposed equations.

This study reports some numerical simulations for showing the ability of the presented technique in solving the studied mathematical models arising in biology. The obtained results by the developed numerical scheme are in good agreement with the results reported in the literature. Besides, a simulation of the proposed model is done on buttery shape domain in two-dimensional space.

This study develops the BKM combined with MAEM for solving the coupled systems of (advection) reaction–diffusion equations in two-dimensional spaces. Besides, it does not need the fundamental solution of the mathematical models studied here, which omits any difficulties.