“…The case studied was modeling Station Black-Out (SBO) accident in PSB-VVER ITF. PSB-VVER is a large scale (1:300) ITF which has been widely used in validation of TH codes for VVER-1000 NPPs (Del Groudev et al, 2005;Heralecky, 2014;Nevo et al, 2008). Quality assessment of TH codes for application in VVER-type NPPs, involves the availability of qualified nodalizations as well as experimental data (Bucalossi et al, 2012).…”