AbstractsEngineering

The influence of laminar-turbulent transition on a propeller blade’s performance has been investigated in this study, both numerically and experimentally. The computational fluid dynamics (CFD) is performed using the TAU code developed by the German Aerospace Center, as well as an existing propeller lifting-line code. The laminar-turbulent transition is simulated using the γ-Reθt correlation based transition model, which is compared to the results of the Spalart-Allmaras one-equation turbulence model. To validate the CFD data, experiments are performed in the Open Jet Facility of Delft University of Technology, where the laminar-turbulent transition is measured using an infrared camera. The results show that at high advance ratios, the difference between the CFD simulations using the laminar-turbulent transition model and the one-equation turbulence model is large. This can be explained due to the trailing edge separation which is present in the case where laminar-turbulent transition is modeled. At lower advance ratios, the difference between the two CFD models becomes smaller. This is due to the fact that a larger portion of the flow over the blade becomes turbulent. Comparing the CFD results to the experimental results it can be seen that the location of transition predicted by the CFD simulations shows some agreement with the experimental results.