Investigation of Multi-dimensional Aerodynamic Characteristics of UAV Rotor Subjected to Horizontal Inflow

doi:10.12382/bgxb.2024.0316

Abstract

Abstract:

In order to study the effect of horizontal inflow on the aerodynamic characteristics of small unmanned aerial vehicle (UAV) rotors,the wind tunnel test and numerical simulation are conducted to obtain the multi-dimensional aerodynamic data and wake vortex diffusion characteristics of UAV rotors under different inflow speeds.A low-speed wind tunnel is used to simulate horizontal inflow,and a six-component force-moment sensor is used to measure the aerodynamic forces the rotational speeds from 2000r/min to 9000r/min.The experimental study focuses on analyzing the variations of lateral force,and pitch and roll moments in the rotational plane.The influence of inflow speed on surface pressure distribution during the rotational period and the morphological characteristics of the near-field wake vortex are discussed from the numerically simulated results.The results indicate that the optimal rotational speed range of rotor is 4000-6000r/min under the action of horizontal inflow The x-axis force in the rotational plane is the primary contributor to the lateral force,with both x-axis and y-axis moments playing roles simultaneously.The lateral forces and moments become significant at inflow speeds above 5m/s and must be considered in dynamic analysis.The horizontal inflow disrupts the symmetrical feature of the rotor wake vortex.The inflow with greater speed leads to a larger inclination angle,causing the diffusion evolution of wake vortex to be compressed.

Key words: unmanned aerial vehicle, horizontal inflow, aerodynamics, rotor wake vortex, lateral force, pitch and rolling moment

LIU Cong, LI Baiqing, ZHANG Zongwei, SHAN Zezhong. Investigation of Multi-dimensional Aerodynamic Characteristics of UAV Rotor Subjected to Horizontal Inflow[J]. Acta Armamentarii, 2025, 46(3): 240316-.

Figures/Tables 19

Fig.1 Large-scaled low-speed wind tunnel

Fig.2 Rotor’s six component force-torque experimental bench

Fig.3 Rotor geometric model

Fig.4 Chord length and twist angle distribution

Fig.5 Computational domain and boundary conditions

Fig.6 Computational mesh

Fig.7 Variation of axial force-torques from experiment and CFD simulation with rotor speed

Fig.8 Variation of axial force with rotor speed at different inflow velocities

Fig.9 Variation of axial torque with rotor speed at different inflow velocities

Fig.10 Variation of axial force coefficient with rotor speed at different inflow velocities

Fig.11 Variation of axial torque coefficient with rotor speed at different inflow velocities

Fig.12 Variation of figure of merit with rotor speed at different inflow velocities

Fig.13 Variation of lateral force with rotor speed at different inflow velocities

Fig.14 Variation of lateral force coefficient with rotor speed at different inflow velocities

Fig.15 Variation of x-axis moment with rotor speed at different inflow velocities

Fig.16 Variation of y-axis momentwith rotor speed at different inflow velocities

Fig.17 Surface pressure distribution at different inflow velocities

Fig.18 Variation of x-axis moment coefficient with rotor speed at different inflow velocities

Table 1 Effect of inflow velocity on diffusion distribution of wake vortex in near field

转速/ (r·min^-1)	来流速度/(m·s^-1)
转速/ (r·min^-1)	0	5	10	15
2000
5000
8000

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