Estimate of the truncation error of a finite volume discretisation of the Navier-Stokes equations on colocated grids
For researchers in computational fluid dynamics, this provides a practical tool for error estimation in colocated grid finite volume methods, though it is an incremental extension of existing concepts.
The paper proposes a methodology to estimate the truncation error of finite volume discretizations of the incompressible Navier-Stokes equations on colocated grids, validated by numerical experiments. The method enables error estimation by restricting solutions to coarser grids and applying the discrete operator.
A methodology is proposed for the calculation of the truncation error of finite volume discretisations of the incompressible Navier-Stokes equations on colocated grids. The truncation error is estimated by restricting the solution obtained on a given grid to a coarser grid and calculating the image of the discrete Navier-Stokes operator of the coarse grid on the restricted velocity and pressure field. The proposed methodology is not a new concept but its application to colocated finite volume discretisations of the incompressible Navier-Stokes equations is made possible by the introduction of a variant of the momentum interpolation technique for mass fluxes where the pressure-part of the mass fluxes is not dependent on the coefficients of the linearised momentum equations. The theory presented is supported by a number of numerical experiments. The methodology is developed for two-dimensional flows, but extension to three-dimensional cases should not pose problems.