The effect of an interacting internal crack on the edge crack in a transient thermal stress field is evaluated using digital photothermoelastic experiments and finite element (FE) analysis. Initially, a transient thermal stress field is simulated using FE analysis for which the thermal boundary conditions are set based on the experimental isochromatic fringes. In this simulated thermal stress field, single edge crack with and without an internal short crack interacting at different configurations are modeled and the non-dimensional Stress Intensity Factor (SIF) values are evaluated at different time intervals. It is observed that the asymmetric and collinear configurations tend to increase the SIF of the edge crack whereas a parallel crack tends to decrease the SIF of the edge crack. For experimental evaluation, specimens with a single edge crack and asymmetric configuration of interacting cracks are considered and the non-dimensional SIF values are evaluated under a thermal stress field generated by edge heating and cooling. The results are compared with those obtained using the FE analysis.

中文翻译：

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用数字光弹性和有限元研究热载荷下裂纹相互作用效应

使用数字光热弹性实验和有限元 (FE) 分析来评估瞬态热应力场中相互作用的内部裂纹对边缘裂纹的影响。最初，使用有限元分析模拟瞬态热应力场，根据实验等色条纹设置热边界条件。在这个模拟的热应力场中，对具有和不具有内部短裂纹在不同配置下相互作用的单边缘裂纹进行建模，并在不同的时间间隔评估无量纲应力强度因子 (SIF) 值。据观察，不对称和共线的配置倾向于增加边缘裂纹的 SIF，而平行裂纹倾向于降低边缘裂纹的 SIF。对于实验评估，考虑具有单个边缘裂纹和不对称相互作用裂纹配置的试样，并在边缘加热和冷却产生的热应力场下评估无量纲 SIF 值。将结果与使用有限元分析获得的结果进行比较。