The next-generation physics pre-processor, CFX-Pre, is used to define simulations.

Multiple meshes may be imported, allowing each section of complex geometries to use the most appropriate mesh.

Analyses, which consist of flow physics, boundary conditions, initial values, and solver parameters, are also specified. A full range of boundary conditions, including inlets, outlets and openings, together with boundary conditions for heat transfer models and periodicity, are all available in Ansys CFX through CFX-Pre; for details, see CFX-Pre Basics in the CFX-Pre User's Guide.

Complex simulations are assembled from one or more configurations, each of which combines an analysis definition with other related tasks such as remeshing. Control over the configuration execution order and inter-configuration solution dependencies then facilitates the setup of relatively common simulations, such as those involving the initialization of a transient analysis using results from a steady-state analysis. Use of multiple configurations and control also facilitates the setup of increasingly complex simulations of, for example, performance curves for turbo-machines or internal combustion engines with evolving geometry and physics.