Preprocessing is the first step in building and analysing a flow model. It includes building the model (or importing from a CAD package), applying a mesh, and entering the data.
After pre-processing, a CFD solver does the calculations and produces the results. To assist with the preprocessing stage, Fluent’s new TGrid 3.6 CFD Preprocessor is being delivered with the company’s HexCore meshing technology. This is particularly useful for designers who need to model fluid flow problems with open spaces, such as in a cabin interior, where a high mesh quality is required.
HexCore itself is a fully automatic meshing tool. It first creates a hanging-node Cartesian mesh, ensuring comparable cell sizes close to the boundary. Then, if needed, it automatically accounts for pre-defined prism cells, giving greater fidelity. Lastly, it adds high-quality tetrahedral cells in the transition area between the Cartesian core and the boundary. All the while, the mesh density variation can be controlled both globally and locally.
According to TGrid Product Manager Erling Eklund, ‘50% cell count reduction can be obtained on these types of applications using HexCore with no sacrifice in mesh quality.’ Fluent says that the HexCore technology has already passed a rigorous set of 40 industrial automotive test cases of up to 7 million cells in size.
TGrid 3.6 is available now to all users of Fluent CFD software.