Effects of gusty flow on aerodynamic performance of multirotor drone propellers in hovering flight

Abstract

The effects of cross flow and fluctuating cross flow on the aerodynamic performance of multirotor drone propellers were investigated by using wind tunnel testing and numerical simulations. Three hovering propellers were examined and were designed based on Adkins and Liebeck theory with modifications. Thrust coefficient 𝐶 and power coefficient 𝐶 of each propeller were experimentally measured and Figure of Merit 𝐹𝑀 was evaluated. From the cross flow experiments and numerical simulations, 𝐶 , 𝐶 and 𝐹𝑀 calculated were in reasonable agreement with the experimental results at high cross flow velocity. The results implicated that a stall might occur at near the root of the propeller as well as demonstrated that the starting point of the propeller design played a role in aerodynamic performance under the cross flow conditions. Moreover, from the fluctuating cross flow experiments, 𝐶 , 𝐶 and 𝐹𝑀 fluctuated in time and the propellers are more susceptible to cross flow and fluctuating cross flow at lower rotational speed in terms of the amount of change of aerodynamic forces.