为了定量分析超声红外无损检测中复合材料裂纹面之间接触、碰撞、摩擦等相互作用引起的发热现象,建立超声激励下复合材料微裂纹板热传导的显式瞬态动力学有限元模型,并由此获得沿裂纹剖面的温度场分布图,从而证明对含裂纹缺陷的复合材料进行超声波激励相当于对裂纹进行选择性加热,缺陷处温升幅值大小与初始温度场无关。研究结果显示采用平衡主-从接触算法和整体-局部接触搜索算法可有效模拟裂纹缺陷在超声波激励下的接触、滑移及摩擦等相互作用机理,揭示复合材料局部微裂纹的发热及热传导规律。
To quantitatively analyze the heating phenomenon between composite crack surfaces caused by the interaction including contact, collision and friction in the ultrasonic and infrared non-destructive testing, an explicit transient dynamics finite element model of composite plate with micro-cracks under ultrasonic excitation is constructed and the temperature field distribution along the crack profile is obtained. It is proved that the ultrasonic excitation of the composite con- taining defects is equivalent with the selective heating of the crack phenomenon. The magnitude of temperature rise in the defect domain is also proved to be irrelative with the initial temperature field. Research results show that master-slave contact algorithm and global-local contact search algorithms can effectively simulate the interaction mechanism of cracks contact, slip and friction in the process of ultrasonic excitation. The heat radiation and conduction law of local microcracks of composite are also revealed.