摘要
直升机恶劣的工作环境使得其结构极易萌生孔边裂纹并演化扩展,使其结构完整性及承载能力降低。为监测直升机连接结构的孔边裂纹,常采用压电导波的结构健康监测技术开展监测研究。但由于裂纹扩展初期的小裂纹不易监测且连接结构具备大尺寸通孔构型,导波监测的准确性仍有待提高。因此,围绕耳片连接结构裂纹监测的准确性问题,提出了一种基于压电导波阵列的孔边裂纹监测方法。首先,通过获取的压电导波阵列信号,提取了全网络损伤特征信息。其次,基于均值法构建了损伤报警阈值,实现了损伤报警。再次,基于连接结构形式改进了延时累加成像算法,优化了概率分布,进而实现了裂纹的准确定位。最后,通过耳片连接结构裂纹扩展监测试验进行了验证。试验结果表明,所提方法能够实现孔边裂纹的准确报警及定位,定位误差仅在2.01 mm以内,验证了所提方法的有效性和准确性。
The harsh operational environment of helicopters renders their structures highly susceptible to the initiation and propagation of hole-edge cracks around bolt holes,thereby compromising structural integrity and load-bearing capacity.To monitor hole-edge cracks in helicopter attachment lug structures,piezoelectric guided wave-based structural health monitoring(SHM)techniques are commonly employed.However,due to the difficulty in detecting small cracks at the early stages of propagation and the presence of large through-hole configurations in attachment lug structures,the accuracy of guided wave monitoring remains suboptimal.Therefore,addressing the accuracy issues in crack monitoring of attachment lug structures,this study proposes a piezoelectric guided wave array-based method for hole-edge crack detection.Firstly,damage feature information was extracted from acquired piezoelectric guided wave array signals encompassing the entire sensor network.Subsequently,a damage alarm threshold was established using a mean-value method to facilitate damage detection.Furthermore,an improved delay-and-sum imaging algorithm was developed based on the specific configuration of the attachment lug structure to optimize probability distribution and achieve precise crack localization.Finally,validation was conducted through test monitoring of crack propagation in attachment lug structures.Test outcomes demonstrate that the proposed method enables accurate alarm triggering and localization of hole-edge cracks around bolt holes,with localization errors confined within 2.01 mm,thereby confirming the efficacy and precision of the proposed approach.
作者
王化吉
施利明
戴玉山
邱雷
WANG Huaji;SHI Liming;DAI Yushan;QIU Lei(China Helicopter Research and Design Institute,Jingdezhen 333000,China;School of Aeronautics,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)
出处
《机械强度》
北大核心
2025年第8期115-122,共8页
Journal of Mechanical Strength
基金
中央高校青年教师科研创新能力支持项目(ZYGXQNJ-SKYCXNLZCXM-D6)。
关键词
关键连接结构
孔边裂纹监测
压电导波
损伤报警
损伤定位
Key attachment structure
Hole-edge crack monitoring
Piezoelectric guided wave
Damage alarm
Damage location
