The use of multicopters for transporting people and goods in urban areas seems conceivable and attractive in order to relieve the ever-increasing traffic. The DLR project City-ATM addresses this issue. However, an additional, focused consideration of two key areas is necessary that affect the acceptance and safety of multicopters: noise and aerodynamic behavior in disturbing winds. Here, knowledge about aircraft cannot be relied upon, as the propulsion concepts and operating conditions differ significantly.
Accordingly, the project AACID (Acoustics and aerodynamics for city drones) is focused on estimating the noise and aerodynamics of multicopters for urban areas. The aim of AACID is to estimate the noise and hazard potential that can arise from disruptive winds during the air transport of people and goods with multicopters in urban environments. The Institutes of Aerodynamics and Flow Technology (coordinator) and Flight Guidance are involved in AACID.
In the project, a two-pronged approach of wind tunnel experiments and numerical simulations is pursued in order to efficiently answer the questions posed in the working hypotheses with quantitative data. Experiments with two free-flying drones take place in the open measurement section of the large low-speed wind tunnel at the DNW. Based on the measurement data, simple models including a scaling concept for the representation of larger drones are derived for the sound prediction. These are used in numerical simulations to determine focusing effects in urban development situations for selected urban locations.
A traffic management system for drones available at the Institute of Flight Guidance is to be expanded as part of the project to include parameters for predicted disturbing winds of other (surroundings-relevant) aircraft as well as for low-noise trajectories, based on the models developed. For this project, two multicopters with an indoor navigation system based on ultra-wide band technology were procured to enable stable flight in the wind tunnel.
DLR Institute of Aerodynamics and Flow Technology (coordinator) DLR Institute of Flight Guidance