Evaluation of Potential Flow Capabilities for Ground Effect Predictions of a Single Propeller

The present work aims to investigate the capabilities of a potential flow approach to predict the ground effect of a single double-blade propeller. Proper models of propeller working close to solid surfaces, e.g, multi-rotor drones or helicopter tail rotors, can be useful for control end manoeuvrability studies. A low-fidelity approach can be suitable for preliminary design stages where the responsiveness is more important than very accurate estimations. The panel code VSPAERO is developed by NASA and implemented in the desktop application Open VSP where it is possible to model several geometries. Firstly, using the propeller outside the ground effect, a mesh sensitivity is documented comparing results with respect to wind tunnel tests. Secondly, the ground is modelled in Open VSP using geometries available in the software. The numerical results are compared to theoretical ones in order to highlight the prediction capability of the proposed approach when the propeller works in ground effect. Moreover, a flow analysis is performed in order to highlight the limitations of the proposed approach to simulate a propeller in ground effect.