Reaktör Gövdesinde Kullanılan Kompozit Levhalardaki Kusurlar Civarında Termal Gerilme Analizi

Abstract

Modelling of composite plate using in the reactor body in nuclear energy plants for thermal effect  The analysis of the stress concentration factor at the crack tip which is perpendicular to the interface of two different materials for various geometries and positions  Modelling by using finite element method which was verified analyticallyThe finite element model of the nuclear wall near the cavity perpendicular to the interface, verification of numerical results with analytical solution, variation of the stress concentration factor with respect to the radius of the tip of the cavityPurpose: In this study, the variation of the thermal stress concentration factor was intended to be determined with respect to the radius and the location of the tip of a cavity, which is perpendicular to the interface of two materials having different coefficients of thermal expansion. Theory and Methods:The dimensions of the region including a small cavity is small with respect to those of the reactor composite body so that this region can be modeled by a plate. The difference between the coefficients of thermal expansion was modeled by different temperature on two regions of a single material plate. The numerical model, which was analyzed by Abaqus, was verified by an analytical solution given in the literature. Various geometries of the numerical model were analyzed varying the radius and the location of the tip of the cavity. Results:The variations of the stress concentration factor were obtained with respect to the variations of the radius and location of the tip of the cavity, separately. Furthermore, second degree parabolas were fitted to the results in order to obtain the stress concentration factor when the radius or the distance of the tip to the interface equal to zero. Conclusion:The analogical approach was applied successfully to the numerical model considered here. The verification of the numerical model for the analysis of thermal stress was presented, which can be used to obtain an empirical expression for calculation of the thermal stress concentration factor comparing with some of the experiments in future.