On the numerical convergence properties of the calculation of the flow around the KVLCC2 tanker in unstructured grids

Abstract

This paper addresses the estimation of numerical errors in the calculation of the

flow around the KVLCC2 tanker at model scale Reynolds number in unstructured grids. The flow solution is based on the Reynolds-Averaged Navier-Stokes equations supplemented by the k − ω SST two-equation eddy-viscosity model using the so-called double-body approach, i.e. free surface effects are neglected. Grid refinement studies are performed for sets of grids gener- ated with the open source code SnappyHexMesh and with the HEXPRESSTM grid generator. Definition of grid refinement ratio in unstructured grids and its consequences for the estima- tion of numerical errors is discussed. Friction and pressure resistance coefficients and mean velocity components at the propeller plane are compared with reference solutions obtained in

nearly-orthogonal multi-block structured grids with the same flow solver ReFRESCO.