(550f) Surface Discretization Considerations for the Boundary-Element Method Applied to Ellipsoidal Particles in Stokes Flow
AIChE Annual Meeting
Wednesday, November 16, 2022 - 4:45pm to 5:00pm
The boundary element method is commonly used for simulating particle motion in Stokes flow, yet there is a scarcity of quantitative studies examining local errors induced by meshing highly elongated particles. In this talk, we study the eigenvalues and eigenfunctions of the double-layer operator for an ellipsoid in an external linear or quadratic flow. We quantify the local and global errors when one changes the interpolation order of the geometry (flat or curved triangular elements) as well as the interpolation order of the double-layer density (piecewise-constant or piecewise-linear over each element). Interestingly, we find that increasing the interpolation order for the geometry and the double layer density does not always guarantee smaller errors. Depending on the nature of the meshing near high curvature regions, the number of high aspect ratio elements, and the nature of the particle geometry, a piecewise-constant density can exhibit lower errors than piecewise-linear density, and there can be little benefit using curved triangular elements compared to linear triangular elements. This talk will provide practical insights on how to appropriately discretize and parameterize 3D boundary element simulations for elongated particles with prolate-like and oblate-like geometries.