脉冲红外热像无损检测是一种可以检测材料内部缺陷的先进技术,在飞机蜂窝板内部积水的无损检测中有应用前景。用有限元分析软件ANSYS对蜂窝板积水的脉冲热像检测法进行数值模拟,研究可检信息参数(如最大温差和最大对比度)与积水量的关系。分析了从近水测检测、从远水侧检测和蜂窝板立放检测三种检测模式。结果表明:在这三种检测模式下,最大温差和最大对比度与积水高度均呈非线性关系,随着积水高度的增加而增大。从近水侧检测时灵敏度最高,其次是蜂窝板立放,而从远水侧检测时灵敏度最低。根据可检信息参数与积水高度的关系曲线可以反向估计积水高度。这些研究结果为蜂窝板积水的脉冲热像检测及表征提供了基本理论依据。
Pulsed thermography(PT) is an advanced technique of detecting internal defects in materials,and expected to have an application in water ingress detection of honeycomb panels.Numerical simulation of PT to detect water ingress in honeycomb panels was carried out by using the finite element analysis software ANSYS,and the relations between information parameters(such as the maximum differential temperature and maximum contrast) and water content were explored.Three testing modes,i.e.detection from near-water side,detection from far-water side and detection as the honeycomb panel is vertically laid were analyzed.The results indicate that,in the three testing modes,both the maximum differential temperature and maximum contrast are an non-linear function of the water height,and increase with the water height.The detection sensitivity from near-water side is the highest,the detection sensitivity as the honeycomb panel is vertically laid takes second place,and the detection sensitivity from far-water side is the lowest.The water height can be evaluated inversely by the curves of the information parameters vs water height.The obtained results provide a theoretical support for water ingress detection and characterization of honeycomb structures by PT.