Horizontal Wind Effect on the Aerodynamic Performance of Coaxial Tri-Rotor MAV

Yao Lei,Yiqiang Ye,Zhiyong Chen

doi:10.3390/app10238612

Abstract

The coaxial Tri-rotor micro air vehicle (MAV) is composed of three coaxial rotors where the aerodynamic characteristics of is complicated in flight especially when the wind effect is introduced. In this paper, the hovering performance of a full-scale coaxial Tri-rotor MAV is analyzed with both the simulations and wind tunnel experiments. Firstly, the wind effect on the aerodynamic performance of coaxial Tri-rotor MAV is established with different rotor speed (1500–2300 rpm) and horizontal wind (0–4 m/s). Secondly, the thrust and power consumption of coaxial Tri-rotor (L/D = 1.6) were obtained with low-speed wind tunnel experiments. Furthermore, the streamline distribution, pressure distribution, velocity contour and vortex distribution with different horizontal wind conditions are obtained by numerical simulations. Finally, combining the experiment results and simulation results, it is noted that the horizontal wind may accelerate the aerodynamic coupling, which resulting in the greater thrust variation up to 9% of the coaxial Tri-rotor MAV at a lower rotor speed. Moreover, the aerodynamic performance is decreased with more power consumption at higher rotor speed where the wind and the downwash flow are interacted with each other. Compared with no wind flow, the shape of the downwash flow and the deformation of the vortex affect the power loading and figure of metric accordingly.

Highlights

Compared with traditional Quad-rotor or Hex-rotor, the coaxial Tri-rotor the coaxial Tri-rotor has a much wider class including a compact structure without redundancy device since the vehicle mass is related to the rotor arm where the Quad-rotor or Hex-rotor is limited with more rotors to avoid rotor conflict
Low-speed wind tunnel tests and numerical simulations are performed to obtain the aerodynamic performance of the coaxial Tri-rotor micro air vehicle (MAV) with the horizontal wind ranged from 0 to
Conclusions are as follows: (1) For a lower rotor speed ranging from 1500 to 1800 r/min, the power required is constant, while the thrust increased up to 9%, which indicated that the coaxial Tri-rotor system with lower speed has larger power loading and better aerodynamic performance

Summary

Introduction

Compared with traditional Quad-rotor or Hex-rotor, the coaxial Tri-rotor the coaxial Tri-rotor has a much wider class including a compact structure without redundancy device since the vehicle mass is related to the rotor arm where the Quad-rotor or Hex-rotor is limited with more rotors to avoid rotor conflict. It provides the unique capability of being able to resist any applied wrench or wind gust or failure tolerance with coaxial rotors (If one rotor, even three rotors, fails the system, it still has the freedom of movement).

Objectives

Results

Conclusion