Note: Presentations may start a few minutes before the time listed in the schedule.
CFD is a key tool for analysis of turbomachines, and is widely used in applications from design assessment/improvement to research into rotating stall inception and other complex phenomena. Increasingly, the computations required require extensive computational resources, with applications such as full-wheel response to inlet flow distortions commonly needing grids with over 100 million cells and multiple rotor revolutions of flow time. The cost structure of many commercial solvers scales, at least in part, with the number of parallel processes employed and so, especially for researchers and designers at smaller companies, commercial codes may not be accessible. In addition, they are typically “black box” tools which is not always desirable. OpenFOAM is a free, open-source CFD package that is widely used, but its application to gas turbine-type turbomachinery has been hindered, until recently, by limitations (now resolved) related to the use of part-annulus computations, as well as the intimidating learning curve for new users due to the lack of a graphical user interface (GUI) for OpenFOAM.
The idea of this tutorial is to demystify the use of OpenFOAM for turbomachinery CFD. Geometry preparation, grid generation, assembly of multiple blade rows into a single computation, case setup, execution, and post-processing are all covered in this tutorial. The focus is on axial turbomachines. Two cases will be covered, a linear compressor cascade with incompressible flow and a single stage axial compressor with compressible flow. For the stage, both steady “frozen rotor” and unsteady “sliding plane” computations will be demonstrated.
