Experimental and numerical simulations on compound stress intensity factor of semi-elliptical cracks on the exchanger outer walls with inclined angles.

Based on the theory of elastic fracture and using direct modeling method, a numerical model was developed for solving the composite stress intensity factor of semi-elliptical cracks on exchanger outer walls with inclined angles. The model exchanger had an outer diameter of φ50 mm, inner diameter of φ44 mm and length of 300 mm. The values of crack plane inclination β (0°, 10°, 20°, 30°, 40° and 45°), crack depth a (0.5 mm, 0.75 mm, 1 mm and 1.25 mm), and crack shape ratio a / b (0.4, 0.5, 0.55, 0.6, 0.7, 0.8, 0.9 and 1.0) were obtained and 3D surface crack model was established. The results were significance for the evaluation of the remaining life of exchanger components. [ABSTRACT FROM AUTHOR]