半透明复合材料脉冲热像检测的有限元仿真分析

摘要

Internal disbonds of translucent laminates were not detected successfully in some cases of infrared pulsed thermography (PT).To investigate the reason,based on the heat theoretical analysis and the optical parameters of experimental measurements,the energy distribution of body heat in PT for the studied obj ects,glass fiber laminates,was obtained.A simulation of PT was performed by 2D modeling,and the inner heat stimulated by illumination was imitated by inner heat-generating.A comparative analysis of the translucent model and the regular model was conducted using the finite element analysis.The results show that the translucent property can lead to failure in PT.The depth and size of a defect that could not be detected were calculated by applying detectable defect signal standard to the simulation results,and it was testified that raising the pulsed energy could contribute to the defect inspection of translucent materials.%利用脉冲热像法对半透明复合材料的内部脱粘进行检测，时有漏检发生。为研究缺陷漏检机理，以玻璃纤维层压板为对象，通过对材料光学受热的理论分析和光学参数试验测量，得到了半透明复合材料脉冲检测时体受热的能量分布规律。建立二维仿真模型，用内生热模拟加热时半透明复合材料的内部受热；利用有限单元法对半透明模型和常规模型进行了对比分析。结果表明，材料的半透明性可导致缺陷漏检。通过仿真曲线与指定缺陷可检标准给出了漏检缺陷对应的深度和大小范围，并验证了提高加热能量可减少缺陷漏检这一结论的正确性。