الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The design of the Advanced Heavy Water Reactor (AHWR) is like advanced CANDU reactor designs, with pressure tubes that contain the reactor fuel and light water coolant. The calandria tubes are surrounded by heavy water moderator which acts as a moderator and reflector. The air between the pressure tubes and calandria tubes provides a thermal insulation between the hot coolant and cold moderator. The cluster of the AHWR contains 24 pins of (Th, Pu) O2 in the outer ring. These pins are fabricated from the recovered plutonium from the pressurized heavy water reactor (PHWR). Recovering plutonium from the spent fuel of PHWR needs mechanical and chemical treatment to separate it from the fission products. In this case the recovered plutonium construes a proliferation concern. In DUPIC fuel (direct use of pressurized spent fuel in CANDU) the bulk of radioactive isotopes are not separated from the mass flow of the fuel. Since DUPIC fuel only needs mechanical treatment, reutilizing it again in AHWR reduces the fuel cost and improves the proliferation resistance of the recovered plutonium. In this work we proposed new DUPIC fuel pins to be loaded in the outer ring of AHWR fuel cluster replacing the (Th, Pu) O2 pins. Six cases were studied depending on the dysprosium concentration in zirconium oxide matrix inside the central rod. The concentration of dysprosium for these cases was 3, 2.5, 2, 1.75, 1.5, 1 wt%. For each case we examined the effect of DUPIC fuel on, (1) The delayed neutron fraction, (2) the generation time, (3) The power distribution among the fuel elements, (4) The coolant void reactivity (CVR), and, (5) The proliferation resistance. The use of DUPIC fuel in AHWR cluster increased the delayed neutron fraction and the generation time for all cases and improved the proliferation resistance.