Tackling the HARTII test case: A joint effort by DLR and JAXA

Abstract

Tackling the HARTII test case: A joint effort by DLR and JAXA The paper focuses on the validation and verification of the high-fidelity aero-mechanical tools of DLR and JAXA. The CFD based tools are validated against the HART II test campaign, for which blade deformations, airloads and noise carpets have been measured. The validation is split into three steps. The first step compares the different blade motion modelling approaches for the baseline case, here either fully or partially utilizing the measured blade motion from the experiment or fully simulating the blade motion. The second step compares the fully elastic modelling between the DLR and JAXA codes for all three HARTII test cases (baseline, minimum noise, and minimum vibration). In the last step, the resolution of the blade-vortex interaction (BVI) is investigated. The effect on the noise carpets of the applied higher order schemes of DLR and JAXA is analyzed for different grid sizes. From this research, it is observed that the blade motion can be simulated in a good agreement with the experiment, while for capturing the BVI well requires a higher order method along with a fine mesh resolution in the flow computation.