ANSYS today announced the availability of the Immersed Boundary module for ANSYS FLUENT 12.0 software. Jointly developed by ANSYS and long-time partner Cascade Technologies Inc., the module dramatically reduces the amount of time needed for fluid flow simulations and provides fast results by directly addressing challenges associated with meshing. This first release, which is fully parallelized, supports the physical models and boundary conditions needed for modeling low-speed external aerodynamics and automotive front-end airflows. The Immersed Boundary tool offers the ability to save customers time and money by reducing the human effort needed to go from computer-aided design (CAD) to an analysis solution.

A conventional fluid dynamics simulation starts with the transfer of CAD data to a grid-generation package, in which a surface mesh and then a volume mesh are generated before the simulation can be set up and the solution run. The effort and time required for such pre-processing tasks can be significant. For example, in cases with complex or dirty geometry that require CAD cleanup, this part of the process may take 50 percent to 90 percent of the total time required for the simulation. The Immersed Boundary module addresses such issues by providing a rapid, automated, preliminary design approach. “This is an ideal tool for reducing lead time during the early stages of the product development cycle, when it is crucial that design evaluations are made rapidly. The Immersed Boundary module helps engineers identify the most promising designs, then use traditional methods for the final high-fidelity analysis,” said Dipankar Choudhury, vice president of corporate product strategy and planning at ANSYS, Inc. “Because of our software’s open and flexible architecture, ANSYS can readily partner with others in the engineering simulation ecosystem to deliver immediate customer benefits — in this case, we partnered with Cascade Technologies, which has many years of fluid dynamics experience, to bring about a more efficient design process.” The immersed boundary method is fully compatible with high-performance computing offerings from ANSYS, which can further reduce analysis time.

Fluid flow simulations using the Immersed Boundary module for ANSYS FLUENT 12.0 software start with the surface data of the simulation geometry in the STL file format, which is commonly used in rapid prototyping and computer-aided manufacturing. This CAD geometry does not need to be clean, does not require smooth surfaces or geometry connectivity, and may contain overlapping surfaces, small holes and even missing parts. The simulation geometry is meshed automatically. Mesh refinement also is carried out automatically after specifying the desired resolution on the boundaries, ensuring the accuracy required for preliminary design evaluation. Using the immersed boundary meshing technique greatly reduces the amount of time spent preparing the geometry for meshing and creating the mesh.