An improved height function technique for computing interface curvature from volume fractions

An improved height function technique for calculating the interface curvature from volume fractions in three dimensions is presented. A detailed analysis of the performance of the height function technique shows that, depending on the interface orientation relative to the computational mesh, appropriate discretization of the partial derivatives of the height function may considerably reduce the computed interface curvature errors, and thus the spurious currents induced in flows with surface tension effects. The accuracy and efficiency of the improved height function technique for 3D problems is compared with those of a convolution technique.