基于稀疏重构的蜂窝夹层复合材料板中Lamb波传播特性估计方法

Sparse reconstruction-based estimation for the characteristics of Lamb wave propagation in composite honeycomb structures

针对航天器装备中蜂窝夹层复合材料板中的超声Lamb波传播特性难以准确估计的问题,提出基于导波信号稀疏表达与重构方法的传播特性曲线估计方法。首先,根据Lamb波传播的散射模型建立Lamb波在频率-波数域下的稀疏表达方程;然后,以Lamb波频率-波数域表达的稀疏性为约束条件,建立基于l_(1)范数的基追踪消噪求解方法;最后,通过提取重构的导波频率-波数域表达结果脊线,可准确获取Lamb波传播的频散速度曲线。在蜂窝夹层复合材料机翼结构上进行测试实验验证的结果表明,该方法能在有限次数的测试下保证传播特性曲线的估计精度,具有较好的工程应用前景。

To accurately estimate the propagating features of the Lamb waves in composite honeycomb structures,a sparse representation and reconstruction method is proposed for the frequency-wavenumber calculation.Firstly,according to the theoretical scattering model of the Lamb waves,the sparse formulation is established regarding the Lamb wave representation in the frequency-wavenumber domain.Secondly,taking the sparse distribution as a constraint,the sparse function can be solved by the basis pursuit denoising method,with the use of the l_(1) norm optimization.Finally,the dispersion relation can be extracted via tracing the ridge in the reconstructed wave frequency-wavenumber domain.An experiment is carried out on an aircraft wing made of composite honeycomb.It is shown that the proposed method is reliable to guarantee the estimation accuracy of the propagation characteristic curve under finite numbers of testing,thus can be used in engineering applications.