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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Yoshiyuki Kataoka, Tadashi Fujii, Michio Murase
Nuclear Technology | Volume 116 | Number 1 | October 1996 | Pages 127-135
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT96-A35317
Articles are hosted by Taylor and Francis Online.
To evaluate the heat release characteristics of a primary containment vessel (PCV) external spray (one of the PCV cooling systems utilizing the steel PCV wall as the heat transfer medium), the thermal-hydraulic characteristics of the falling liquid film on the PCV surface have been investigated experimentally. Then, the performance of the PCV external spray cooling system was evaluated using the experimental findings. The following results were obtained: 1. Heat transfer coefficients of the falling liquid film under steady-state conditions were increased as the film flow rate per unit length of the liquid film width increased, and they agreed with Wilke’s correlation within about ±15%. 2. The PCV surface temperature, when preheated up to 150°C, which is the supposed PCV temperature under a severe accident, decreased below 100°C within a few seconds when the PCV external spray was initiated, and boiling on the PCV surface could not be maintained. 3. Heat transfer coefficients of the falling liquid film under transient conditions were higher initially due to the boiling effect; however, they decreased rapidly and approached those under steady-state conditions. 4. The PCV external spray for the conceptually designed PCV could suppress the PCV pressure below the design goal under a severe accident (failure of core cooling under low pressure). The maximum PCV pressure decreased as the spray flow rate increased and as the ratio of the PCV surface covered by the falling liquid film increased.