The Effect of azimuthal temperature distribution on the ballooning and rupture behavior of Zircaloy-4 cladding tube under transient-heating conditions

成川 隆文; 天谷 政樹

Journal of Nuclear Science and Technology, 53(11), p.1758 - 1765, 2016/11

https://doi.org/10.1080/00223131.2016.1158671

In order to investigate the effect of azimuthal temperature distribution on the ballooning and rupture behavior of Zircaloy-4 (Zry-4) cladding tube, laboratory-scale experiments on non-irradiated Zry-4 cladding tube specimens were performed under transient-heating conditions which simulate loss-of-coolant-accident (LOCA) conditions by using an external heating method, and the data obtained were compared to those from a previous study where an internal heating method was used. The maximum circumferential strains (s) of the cladding tube specimens were firstly divided by the engineering hoop stress (). The divided maximum circumferential strains, s, of the previous study, which used the internal heating method, were then corrected based on the azimuthal temperature difference (ATD) in the cladding tube specimen. The s for the external heating method which was used in this study agreed fairly well with the corrected s obtained in the previous study which employed the internal heating method in the burst temperature range below 1200 K. Also, the area of rupture opening tended to increase with increasing of the value which is defined as multiplied by . From the results obtained in this study, it was suggested that and the size of rupture opening of a cladding tube under LOCA-simulated conditions can be estimated mainly by using , and ATD in the cladding tube specimen, irrespective of heating methods.