A pitching and plunging dynamic test equipment of rotor blade airfoils in the FL-11 wind tunnel
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摘要: 为全面开展直升机旋翼动态失速研究,在FL-11风洞研制了俯仰/沉浮两自由度动态试验装置。首先设计试验装置的机械结构,并利用有限元法对机械支撑框架和运动基座进行静力学和模态分析;其次采用多电机同步驱动实现翼型俯仰和沉浮运动,利用SIMOTION D和S120构建的运动控制系统保证控制精度;最后利用基于龙门轴锁定增益补偿算法的同步控制技术提升电机同步精度,并通过电子凸轮技术实现振幅和频率的无级调节。结果表明:该装置能实现俯仰、沉浮振荡运动以及耦合振荡运动,俯仰运动最大振幅为15°、最高频率为5 Hz;沉浮运动最大振幅为130 mm、最高频率为5 Hz;角度和位移精度分别为3′和1 mm。该装置已成功应用于CRA309翼型动态气动特性风洞试验,为深入研究动态失速特性提供了试验平台。Abstract: In order to fully study the dynamic stall of the helicopter rotor, a pitching and plunging dynamic test device is developed in the FL-11 wind tunnel. Firstly, the paper introduces the design of its mechanical structure, and the statics and model analysis of the mechanical frame and the moving base is conducted through the finite element analysis. Then, the pitching and plunging oscillatory motion of the device is achieved by the multi-motor synchronous driving control, and the control precision is guaranteed through the motion control system based on SIMOTION D and S120. Finally, the synchronous control technology based on the locked gain compensation algorithm of the gantry axis is used to improve the synchronous precision of the motor, and the stepless adjustment of the amplitude and frequency is realized by the electronic CAM technology. The results show that the device can implement the pitching motion and the plunging motion separately or in conjunction, the maximum amplitude of the pitching oscillation is 15°, the highest frequency is 5 Hz, the maximum amplitude of the plunging oscillation is 130 mm, the highest frequency is 5 Hz, and the angle and displacement accuracy is 3′ and 1 mm respectively. The device has been successfully applied to the aerodynamic characteristics wind tunnel test of CRA309 airfoil, which provides a test platform for in-depth study of dynamic stall characteristics.
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Key words:
- rotor airfoil /
- dynamic stall /
- wind tunnel test /
- coupled oscillatory
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表 1 前五阶固有频率
Table 1. The first five order inherent frequencies
阶数 机械支撑框架固有频率/Hz 运动基座固有频率/Hz 1 20.28 948.12 2 22.46 984.86 3 27.84 1043.40 4 77.61 1212.10 5 83.29 1358.70 -
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