CFD Time Transformation Delivers Accurate Turbomachinery Unsteady Transient Flows Faster Than Conventional Methods

Unsteady methods are becoming increasingly important in turbomachinery design and optimization because they model transient flows and performance more realistically. Unfortunately, using time-accurate CFD simulations to understand these unsteady flows in compressor stages can be computationally expensive. In recent years, ANSYS has been working on methods for modelling the transient flows in turbomachinery stages that require as few as single-blade passages per row but with equivalent accuracy. As a result, engineers can drastically reduce computational time and memory resources by up to 10X.

Unsteady Flows in a Centrifugal Compressor transient flows

Centrifugal Compressor Stage geometry and CFD simulation images created
using the Time Transformation method

Our engineers have been collaborating with the team at GE Oil and Gas in Le Creusot, France to study Time Transformation (TT) — one of these methods. In a recent paper, they concluded that the Time Transformation method was able to accurately predict the transient flow behavior of unsteady flow in a centrifugal compressor stage equipped with a vaned diffuser and cavities. In comparison with the reference solution (TRS), the TT method experimental data showed a good agreement and the results correlated well. In addition, the TT method demonstrated a strong ability to improve run time and reduce memory requirements. You can learn more about ANSYS TT and other transient blade row methods in our on-demand webinar.

These GE and ANSYS researchers will be presenting the detailed results in a paper entitled Unsteady Flow in a Centrifugal Compressor Stage Equipped with a Vaned Diffuser and Cavities at the upcoming ASME Turbo Expo in June. If you will be in Charlotte, NC please plan to attend their presentation.

And don’t forget to visit ANSYS in booth number 701 at the Charlotte Convention Center. You can learn more about ANSYS is up to at the Turbo Expo here.

Finally, I want to give a big shout out to the authors: François Moyroud and Christophe Corneloup of GE and Mohand Younsi and Antoine Baldacci of ANSYS. Nice work! Learn more: Proceedings of ASME Turbo Expo 2017, GT2017, July 26-30, 2017, NC, USA