Search

Abstract: In order to study the irradiation performance of fuel spheres for the 10MW high-temperature gas-cooled reactor (HTR-10), two in-pile irradiation tests were performed. The first irradiation test was performed in the Russian reactor IVV-2M from July 2000 to February 2003. The four irradiated fuel spheres were randomly taken from the first product batches. The central temperature of irradiated fuel spheres during this irradiation was kept between 950 and 1050°C. The maximum burnup of the irradiated spheres was 107,000MWd/tU and the maximum fast neutron fluence (E >0.1MeV) was 1.31×1025 m−2. The release-to-birth rate ratios (R/B) of Kr and Xe fission products were 10−7 to 10−5. The second irradiation test was performed in HFR Petten (HFR-EU1) from September 29, 2006 to February 19, 2010. Experiment HFR-EU1 consisted of 3 German AVR pebbles and 2 INET pebbles. The two INET pebbles were randomly taken from the latest production batch. The surface temperature of pebble INET 2 during irradiation was approx. 940°C. The experiment was performed in two campaigns from 29 September 2006 to 24 February 2008 (12 reactor cycles of 28 days) and continued from 19 October 2009 to 19 February 2010 (4 reactor cycles). Up to end of irradiation, the experiment had accumulated 16 reactor cycles totaling 445 efpd and calculated burnup and maximum fast neutron fluence (E >0.1MeV) were 9.3% (pebble INET 1) and 11.6%FIMA (pebble INET 2) and about 4.95×1025 m−2, respectively. At end of irradiation, based on 85mKr, R/B of approx. 8×10−8 was measured. The second irradiation test results are much better than the first. The irradiated sample manufacture technology and characterization, irradiation conditions and results of two irradiation tests are compared in detail in this paper. [Copyright &y& Elsevier]

Abstract: An irradiation test of four spherical fuel elements (SFE) had been performed in the Russian reactor IVV-2M. The elements were sampled randomly from the first and second product batches which were manufactured for the 10MW high-temperature gas-cooled test reactor (HTR-10). The maximum burnup of the irradiated fuel elements reached 107,000MWd/tU and the maximum fast neutron fluence was 1.31×1025 m−2. The release-to-birth rate ratio (R/B) did not increase significantly during irradiation. However, an in-pile heating-up test of element SFE 7 in Capsule 5 led to a failure of approximately 6% of the coated particles. After the test it was estimated that the fuel temperature had very likely been much higher than the intended 1600°C. [Copyright &y& Elsevier]

Abstract: In order to evaluate if the fuel elements and their components (matrix material and coated fuel particles) can meet the design requirements of 10MW high temperature gas-cooled reactor (HTR-10), an irradiation testing with four spherical fuel elements, 60 matrix material specimens of 5mm×5mm×40mm and 13,500 coated fuel particles was performed in Russian IVV-2M reactor from July 2000 to February 2003. The irradiation temperature was 1000°C. The fast neutron fluence of matrix material specimens reached 1.3×1021 cm−2 (E >0.1MeV). Post-irradiation examination contained the visual inspection, dimension measurement and determining the density, porosity, specific electrical resistance and bending strength. The irradiation results are given in this paper, and show that the matrix material for spherical HTR-10 fuel elements made from the domestic raw materials and fabricated by the quasi-isostatic room-temperature moulding process is suitable as a structural material for spherical HTR fuel elements. [Copyright &y& Elsevier]