GEMS has been developed as a versatile geometry pre-processor for engineering analysis, principally for Computational Fluid Dynamics (CFD) codes. Its key feature is the way in which it integrates with Computer-Aided Design (CAD) systems by providing native support for all CAD geometry. GEMS provides pre-processing to a range of CFD codes, from vortex-lattice to multiblock Navier-Stokes, and to numerical analysis methods in other fields such as electromagnetics. Its "plugin" architecture enables core functionality to be supplemented by application-specific support. For example the NEWPAN and SAUNA Plugins provide custom interfaces respectively to Flow Solutions' panel method and QinetiQ's multiblock system.
GEMS provides an easy-to-use, powerful method for rapidly converting geometrical models produced within a CAD system (input typically as surfaces via IGES or STEP, or as point sets) to surface grids for CFD. This stage has in the past proved to be *the* major bottleneck in the analysis cycle, estimated by NASA to account for 70% to 80% of the overall solution time. GEMS is designed to address this by providing functionality such as CAD surface repair, CAD surface construction and modification, and structured and unstructured surface grid generation. These tools are presented in a way that is designed to be accessible to the application engineer who may not necessarily have prior CAD expertise.