TOKE summary report

The thermal-hydraulic experiments and code validation (TOKE) project addressed both the experimental and computational aspects of nuclear safety studies. Integral VVER related experiments dealing with a steam generator collector header rupture incident and with non-condensable gas behaviour in the primary circuit were carried out in the PArallel Channel TEst Loop (PACTEL). Local loading effects due to water flow and thermal stratification in a T-joint of a hot horizontal pipe and a cold vertical tube were investigated in a purpose-built test loop in co-operation with the structural integrity (STIN) project. The behaviour of non-condensable gas during the first seconds of a conceivable large break loss-of-coolant accident (LBLOCA) blowdown to a boiling water reactor (BWR) condensation pool was also studied in the separate effect tests related subproject. For this purpose, a test rig with a scaled down water pool, blowdown pipes, an emergency core cooling system (ECCS) strainer and a pump was designed and constructed in Lappeenranta University of Technology (LTKK). Thermal-hydraulic and computational fluid dynamics (CFD) calculations with the codes APROS and Fluent, respectively, supported the planning and analysis of both the integral and separate effect tests. (orig.)