Multirotor drones are increasingly used for measuring aerosols and gases. However, propeller-induced airflow can alter particle concentrations and gas distributions, potentially biasing observations. We derive a theoretical solution for the airflow generated above multirotor drones in hover, providing a general framework to estimate propeller-induced velocities using only known parameters, such as drone weight, propeller number, and propeller size. To validate this model, we combined computational fluid dynamics simulations with in situ outdoor measurements on three consumer drones: the Da-Jiang Innovations (DJI) Matrice 300 real-time kinematic (RTK), Matrice 600 Pro, and Agras T30. Simulations incorporated recorded motor rotational speeds during actual hover flights, and the results were compared with measurements from hot-wire anemometers at multiple probe points. This combined theoretical, numerical, and experimental approach provides a foundation for more informed drone-based aerosol and gas sampling. Considering these results can help guide the design of mounting systems for aerosol and gas inlets on multirotor drones.
Eckert et al. (Thu,) studied this question.