Aerodynamic impact of a streamwise vortex on a propeller

In some situations, a vortex is involved in the inflow of a propeller, e.g. a ground vortex or a vortex shed from the upstream parts of the airframe of the aircraft. In order to study the impact of the vortex on the propeller, the Batchelor vortex is utilised to model the impinging vortex, and its effect on the propeller is calculated by Computational Fluid Dynamics. The loading on the propeller increases due to the impingement of a contra-rotating vortex, and the opposite is true for a co-rotating vortex. However, the torque coefficient of the propeller changes consistently with the thrust coefficient which leads to the efficiency of the propeller being independent of the impinging vortex. With the vortex impinging on the propeller, a strong pressure fluctuation on the blade is observed, especially on the leading edge of the blade. This cyclic pressure also results in a periodic bending moment on the blade, which may have an impact on the structural fatigue of the blade.