Automatic multiblock decomposition using hypercube++ for grid generation

Abstract

A new method for an automatic multiblock decomposition of a field around any number of complex geometries is proposed. This method is based on hypercube++ data structure to represent the hierarchical relationship between various types of hypercubes while the geometry of the hypercube is represented by non-uniform rational B-splines (NURBS) volume which maps the physical space of a hypercube onto the parameter space. The generation of grid topology based on the hypercube++ structure consists of two main steps: (1) the hypercube++ generation step, which is applied to the region around a single shape element, for example a wing in an airplane, to generate an appropriate hypercube; and (2) the hypercube++ merging step, which merges simple hypercubes or the ones merged already into a single but more complex hypercube++ to represent the regions around the shape composed of several shape elements. This approach will be demonstrated with some examples to show that it allows a user to construct a multiblock decomposition in a matter of minutes for any three dimensional configurations in an automatic manner.