Abstract
A new reactor burnup strategy CANDLE was proposed, where shapes of neutron flux, nuclide densities and power density distributions remain constant but move to an axial direction. Here important points are that the solid fuel is fixed at each position and that any movable burnup reactivity control mechanisms such as control rods are not required. This burnup strategy can derive many merits. The change of excess reactivity along burnup is theoretically zero, and shim rods will not be required for this reactor. The reactor becomes free from accidents induced by unexpected control rods withdrawal. The core characteristics, such as power feedback coefficients and power peaking factor, are not changed along burnup. Therefore, the operation of the reactor becomes much easier than the conventional reactors especially for high burnup reactors. The transportation and storage of replacing fuels become easy and safe, since they are free from criticality accidents. In our previous works it is appeared that application of this burnup strategy to neutron rich fast reactors makes excellent performances. Only natural or depleted uranium is required for the replacing fuels. The average burnup of the spent fuel is about 40% that is equivalent to 40% utilization of the natural uranium without
More>>
Sekimoto, H;
Yan, M
[1]
- Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology (Japan)
Citation Formats
Sekimoto, H, and Yan, M.
Design study on small CANDLE reactor.
Turkey: N. p.,
2007.
Web.
Sekimoto, H, & Yan, M.
Design study on small CANDLE reactor.
Turkey.
Sekimoto, H, and Yan, M.
2007.
"Design study on small CANDLE reactor."
Turkey.
@misc{etde_20968220,
title = {Design study on small CANDLE reactor}
author = {Sekimoto, H, and Yan, M}
abstractNote = {A new reactor burnup strategy CANDLE was proposed, where shapes of neutron flux, nuclide densities and power density distributions remain constant but move to an axial direction. Here important points are that the solid fuel is fixed at each position and that any movable burnup reactivity control mechanisms such as control rods are not required. This burnup strategy can derive many merits. The change of excess reactivity along burnup is theoretically zero, and shim rods will not be required for this reactor. The reactor becomes free from accidents induced by unexpected control rods withdrawal. The core characteristics, such as power feedback coefficients and power peaking factor, are not changed along burnup. Therefore, the operation of the reactor becomes much easier than the conventional reactors especially for high burnup reactors. The transportation and storage of replacing fuels become easy and safe, since they are free from criticality accidents. In our previous works it is appeared that application of this burnup strategy to neutron rich fast reactors makes excellent performances. Only natural or depleted uranium is required for the replacing fuels. The average burnup of the spent fuel is about 40% that is equivalent to 40% utilization of the natural uranium without the reprocessing and enrichment. This reactor can be realized for large reactor, since the neutron leakage becomes small and its neutron economy becomes improved. In the present paper we try to design small CANDLE reactor whose performance is similar to the large reactor by increasing its fuel volume ration of the core, since its performance is strongly required for local area usage. Small long life reactor is required for some local areas. Such a characteristic that only natural uranium is required after second core is also strong merit for this case. The core with 1.0 m radius, 2.0 m length can realize CANDLE burn-up with nitride (enriched N-15) natural uranium as fresh fuel. Lead-Bismuth is used as coolant. From equilibrium analysis, we obtained the burn-up velocity, output power distribution, core temperature distribution etc. The burn-up velocity is less than 1.0 cm/year that enables a long life design easily. The core averaged discharged fuel burn up depth is about 40%. For more understanding about the effect of the coolant to fuel volume ratio, the comparison between five cases is made. The coolant channel radius is different from each other, while fuel pin pitch is fixed. Further, the comparison is made with fixed coolant channel radius and different fuel pin pitches.}
place = {Turkey}
year = {2007}
month = {Jul}
}
title = {Design study on small CANDLE reactor}
author = {Sekimoto, H, and Yan, M}
abstractNote = {A new reactor burnup strategy CANDLE was proposed, where shapes of neutron flux, nuclide densities and power density distributions remain constant but move to an axial direction. Here important points are that the solid fuel is fixed at each position and that any movable burnup reactivity control mechanisms such as control rods are not required. This burnup strategy can derive many merits. The change of excess reactivity along burnup is theoretically zero, and shim rods will not be required for this reactor. The reactor becomes free from accidents induced by unexpected control rods withdrawal. The core characteristics, such as power feedback coefficients and power peaking factor, are not changed along burnup. Therefore, the operation of the reactor becomes much easier than the conventional reactors especially for high burnup reactors. The transportation and storage of replacing fuels become easy and safe, since they are free from criticality accidents. In our previous works it is appeared that application of this burnup strategy to neutron rich fast reactors makes excellent performances. Only natural or depleted uranium is required for the replacing fuels. The average burnup of the spent fuel is about 40% that is equivalent to 40% utilization of the natural uranium without the reprocessing and enrichment. This reactor can be realized for large reactor, since the neutron leakage becomes small and its neutron economy becomes improved. In the present paper we try to design small CANDLE reactor whose performance is similar to the large reactor by increasing its fuel volume ration of the core, since its performance is strongly required for local area usage. Small long life reactor is required for some local areas. Such a characteristic that only natural uranium is required after second core is also strong merit for this case. The core with 1.0 m radius, 2.0 m length can realize CANDLE burn-up with nitride (enriched N-15) natural uranium as fresh fuel. Lead-Bismuth is used as coolant. From equilibrium analysis, we obtained the burn-up velocity, output power distribution, core temperature distribution etc. The burn-up velocity is less than 1.0 cm/year that enables a long life design easily. The core averaged discharged fuel burn up depth is about 40%. For more understanding about the effect of the coolant to fuel volume ratio, the comparison between five cases is made. The coolant channel radius is different from each other, while fuel pin pitch is fixed. Further, the comparison is made with fixed coolant channel radius and different fuel pin pitches.}
place = {Turkey}
year = {2007}
month = {Jul}
}