Automated Creation of 3-D Overset Grids Directly from Solid Models
John Dannenhoffer, Robert Haimes · 20th AIAA Computational Fluid Dynamics Conference · 2011
One of the challenges when generating overset grids is the decomposition of a conguration into the components around which the various grids will be generated. This step frequently requires that the analyst view the conguration and graphically select the surfaces that will form the boundaries of each grid. Fortunately, many congurations are now generated through solid modelling systems, in which a conguration is generated by combining various primitives into the nal conguration. This paper describes a technique for automatically generating overset grids directly from the solid modeling primitives. The basic idea here is to generate a structured grid for each primitive, which is fairly easy since most solid modellers use simple shapes for their primitives. Once all the grids have been generated, then the three Boolean operators { union, intersect, and dierence { are used in the same way as they were used in generating the solid model. The only information needed here is the feature tree that is already stored in the CAD model. Four main challenges emerge from such an approach. First, conventional overset methods only \union grids; in the current approach, the hole-cutting and interpolation schemes must be modied