Numerical Simulation of Rotorcraft
Aerodynamic Investigation of a Multiple-Rotor Drone in Ground Effect
Larger and heavier drones are being developed along with new trials to built multiple-rotor type eVTOLs which can carry several people. However, the flowfields around multiple rotors where the neighboring rotors are rotating in different directions are very complex and not well understood. Espeicially when the multicopters are hovering near the ground, the so-called ground-effect is considered different with the conventional single rotor helicopters.
Computational model based on a prototype variable-pitch controlled quad-rotor drone is created. Flowfields and the drone performance are investigated for the drone hovering at several different height from the ground. It is found that the flowfields for the quad-rotor drone are much complex compared to those of a single rotor.
Distribution of vortices around a multiple-rotor drone (volume rendering)
Movie of Aerodynamic analysis of vortices around a Multiple-Rotor Drone
Future Type Rotary-wing Aircraft System Technology
In Japan, rotary-wing aircrafts can be extremely useful for disaster relief, mountain rescue efforts, and for emergency transportation from isolated islands. To present the conceptual design idea of a compound helicopter suited to these needs, we are striving to accumulate basic design technology of future rotary-wing aircrafts and to perform pioneering technical development ahead of domestic manufacturers. Through these efforts, we will play a pioneering role in the development of future rotary-wing aircrafts, eventually transferring the acquired technology to private sector manufacturers.
The compound helicopter model which can fly.
The unsteady flow fields around multiple rotary wings such as for the compound helicopters are solved using a multi-disciplinary CFD/CSD coupling analysis code, rFlow3D, which is developed at JAXA. Based on a moving overlapping grid method, it can generate the aerodynamic data together with the blade elastic motions. The complex geometries of the rotorcraft fuselages are resolved based on unstructured grid solvers, FaSTAR or TAS-code. Besides of the applications to helicopters, rFlow3D has also been used for other rotary wings, such as propellers, drones with multiple rotors, and wind turbines.
Surface Cpa distribution
Iso-surface of Cpa around the compound helicopter
Movie of the numerical simulation of the compound helicopter
More information about Helicopter