The computational fluid dynamic modeling of downwash flow field for a six-rotor UAV

Abstract

The downwash flow field of the multi-rotor unmanned aerial vehicle (UAV), formed by propellers during operation, has a significant influence on the deposition, drift and distribution of droplets as well as the spray width of the UAV for plant protection. To study the general characteristics of the distribution of the downwash airflow and simulate the static wind field of multi-rotor UAVs in hovering state, a 3D full-size physical model of JF01-10 six-rotor plant protection UAV was constructed using SolidWorks. The entire flow field surrounding the UAV and the rotation flow fields around the six rotors were established in UG software. The physical model and flow fields were meshed using unstructured tetrahedral elements in ANSYS software. Finally, the downwash flow field of UAV was simulated. With an increased hovering height, the ground effect was reduced and the minimum current velocity increased initially and then decreased. In addition, the spatial proportion of the turbulence occupied decreased. Furthermore, the appropriate operational hovering height for the JF01-10 is considered to be 3 m. These results can be applied to six-rotor plant protection UAVs employed in pesticide spraying and spray width detection.

Keywords

CFD simulation / downwash flow field / numerical analysis / plant protection / six-rotor UAV

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Acknowledgements

This research were supported and funded by The National Key Research and Development Program of China (2016YFD0200700) from China Ministry of Science and Technology, and The Fundamental Research Funds for the Central Universities (2015TC036 and 2017QC139), helped by VIGA UAV Company (Beijing).

Compliance with ethics guidelines

Yongjun Zheng, Shenghui Yang, Xingxing Liu, Jie Wang, Tomas Norton, Jian Chen, and Yu Tan declare that they have no conflicts of interest or financial conflicts to disclose.

This article does not contain any studies with human or animal subjects performed by any of the authors.

RIGHTS & PERMISSIONS

The Author(s) 2018. Published by Higher Education Press. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0)