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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.
Ronald D. Boyd, Sr.
Fusion Science and Technology | Volume 16 | Number 3 | November 1989 | Pages 324-330
Technical Paper | Blanket Engineering | doi.org/10.13182/FST89-A29124
Articles are hosted by Taylor and Francis Online.
Steady-state subcooled water flow boiling experiments were carried out in a uniformly heated horizontal circular channel with an exit pressure of 1.66 MPa and with the mass velocity G varying from 4.4 to 32.0 Mg/m2·s. The test section, which was made of high-strength zirconium-copper, consisted of a tube with an inside diameter of 0.3 cm and a heated length-to-diameter ratio (L/D) of 96.6. The coolant was degassed and deionized water. The inlet water temperature was held constant at 20°C. These experiments are related to high heat flux removal in fusion reactor beam dumps and first walls in compact fusion reactors. For the chosen values of L/D and exit pressure, the measured critical heat flux (CHF) values are higher than any previous values for smooth tubes in the literature. The effect of increasing the pressure from 0.77 to 1.66 MPa is to increase the CHF progressively from 2.0 to 19% as the mass velocity is increased from 4.4 to 25.0 Mg/m2·s. The percent increase in the CHF dropped to 10.0% as G increased from 25.0 to 32.0 Mg/m2·s. Below 25.0 Mg/m2·s, the relationship between the CHF and the mass velocity is linear. Further, an increase in the exit pressure resulted in an increase in the slope of this relationship. However, the local heat transfer coefficient actually decreased as the pressure increased, for the same power level and mass velocity.
