Session: 42-01 - Turbomachinery CFD With OpenFOAM

Paper Number: 100900

100900 - Turbomachinery Cfd With Openfoam 

Title: Turbomachinery CFD With OpenFOAM

Authors/speakers: Jeff Defoe, Associate Professor, University of Windsor

Subject being covered:

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.

The focus is on the “.com” branch of OpenFOAM, for which the latest version is v2206, released in June 2022.

This tutorial will help enable a larger user base for OpenFOAM in the gas turbine/turbomachinery community, and aims to make it easier for new users to “jump in” and start using the code with confidence.

Key learning objectives:

The participants completing the tutorial will be able to:

1. create grids for turbomachinery blade rows using the native OpenFOAM tools blockMesh, snappyHexMesh, and refineWallLayer;

2. set up CFD cases for turbomachines in OpenFOAM, including mesh motion, boundary conditions, and numerics; and

3. compute incompressible and compressible flows through single and multiple blade row computational domains

Preferred session slot: 3 hours

Expected size of audience: 100

Presenting Author: Jeff Defoe University of Windsor

Presenting Author Biography: Associate Professor, Mechanical Engineering, University of Windsor, 2019-present
Assistant Professor, Mechanical Engineering, University of Windsor, 2014-2019
MHI Senior Research Fellow in Turbomachinery and Heat Transfer, Whittle Laboratory, University of Cambridge, 2012-2013
Postdoctoral associate, Gas Turbine Laboratory, Massachusetts Institute of Technology, 2011-2012
PhD, Air-Breathing Propulsion, Massachusetts Institute of Technology, 2011
Master of Applied Science, Mechanical Engineering, University of Windsor, 2007
Honours Bachelor of Applied Science, Mechanical Engineering, University of Windsor, 2005

Authors: