机翼模型应变场分布式光纤监测与重构方法

针对飞行器机翼结构应变场重构问题,提出了一种基于分布式光纤传感器与模态叠加原理相结合的大展弦比机翼缩比模型应变场监测与重构方法。借助ANSYS有限元分析软件,数值模拟得到大展弦比机翼缩比模型在不同载荷下应变分布与应变模态振型。在此基础上,通过在大展弦比铝合金机翼缩比模型展向设置光纤Bragg光栅传感器,实时采集应变分布与变化信息,结合数值仿真得到机翼模型应变模态振型,重构机翼缩比模型应变场分布,应变反演平均误差约为7%。研究结果表明,本研究方法具有非视觉测量、实时性好以及反演精度较高等优点,能够为及时准确获取飞行器翼面应变场分布信息,进而实现机翼气动载荷计算与疲劳寿命预测提供技术支撑。

Monitoring and Reconstruction of Wing Model Strain Field by Distributed Optical Fiber

In the process of high-speed flight, the aerodynamic load acts on the wing of the aircraft as the main bearing structure to produce strain. The monitoring of strain distribution in key regions of wing is an important basis for evaluating the health status of aircraft structures. Therefore, the research on strain monitoring and strain field reconstruction technology of wing structures has important theoretical and practical significance. In this paper, a strain field monitoring and reconstruction method for large aspect ratio wing scaling model based on distributed optical fiber sensor and mode superposition principle is proposed. With the help of ANSYS finite element analysis software, the strain distribution and strain mode shapes of the wing model with large aspect ratio under different loads are simulated numerically. On this basis, by deploying fiber Bragg grating sensors in the direction of large aspect ratio aluminum alloy wing scaling model, strain distribution and variation information are collected in real time. Combining with the strain mode shapes of the wing model obtained by numerical simulation, the strain field distribution of the wing scaling model is reconstructed. The average error of strain inversion is about 7%. The results show that the proposed method has the advantages of non-visual measurement, good real-time performance and high inversion accuracy. It can provide technical support for acquiring timely and accurate strain field distribution information of aircraft wing surface, and then realizing aerodynamic load calculation and fatigue life prediction of aircraft wing.