中文摘要：

研究了热障涂层（TBC）厚度及厚度不均的红外热无损检测（IRTNDT）的建模和基于有限单元法的数值模拟。在柱坐标系下以轴对称模型描述热障涂层结构的瞬态热传导,建立相应的物理模型及有限元模型。用有限元分析软件ANSYS计算涂层结构受热脉冲激励后的温度场,研究热无损检测可检信息参数（如最大温差和最大对比度）与厚度特征参数（厚度差和厚度）的关系。结果表明,在涂层公称厚度一定时,最大温差和最大对比度与厚度差呈非线性关系,它们随着厚度差的增大而增大;在涂层厚度差一定时,最大温差和最大对比度与涂层公称厚度呈非线性关系,它们随着涂层公称厚度的增加而减小。利用计算所得的可检信息参数与厚度特征参数的关系可以反向估计陶瓷层厚度差和厚度。这些研究结果为热障涂层厚度及厚度不均的红外热无损检测及表征提供了基本理论依据。

英文摘要：

Modeling and numerical simulation of infrared thermal nondestructive testing （IR TNDT） for the thickness and its unevenness of thermal barrier coatings （TBC） are studied by the finite element method. The transient heat conduction of TBC structures is described by an axisymmetrical model in cylindrical coordinates,and the corresponding physical model and finite element model are constructed. The temperature field of the TBC structures stimulated by a heating pulse is analyzed by using the finite element analysis software ANSYS,and the relationship between the TNDT information parameters （such as the maximum differential temperature and maximum contrast） and thickness characteristic parameters （thickness difference and thickness） are explored. The results show that at a fixed coating thickness,the maximum temperature difference and maximum contrast are a nonlinear function of the thickness difference and they increase with the increase of thickness differences. At a fixed coating thickness difference,the maximum temperature difference and maximum contrast are a nonlinear function of the coating thickness,and they decrease when the coating thickness increases. The thickness difference and thickness of ceramic coatings can be evaluated inversely by the calculated relationship between the information parameters and the thickness characteristic parameters. These results provide theoretical support for the detection and characterization of the thickness and its unevenness of TBC by IR TNDT.