An algorithm for aligning a quadrilateral grid with internal boundaries

We present a new numerical algorithm that aligns a quadrilateral grid with internal alignment curves (IACs). These IACs can he used to delineate inter nal interfaces, discontinuities in material properties, internal boundaries , or major features of a flow field. The adaptive IAC grid generation algor ithm readjusts a predefined reference grid to create a nearby grid where th e mesh cell edges are aligned with the IACs, On an aligned grid, numerical discretizations of partial differential equations can be formulated to sati sfy the interfacial relations, such as matching fluxes across the discontin uity, to reduce the numerical errors introduced by the discontinuity. We pr esent examples to demonstrate the effectiveness of the IAC grid generation algorithm for multiple embedded interfaces in a quadrilateral grid. (C) 200 0 Academic Press.