Behavior of vibrationally compacted mixed fuel in BN-800

Abstract

The modified computer code MACROS was used to study the behavior of fuel elements with vibrationally compacted mixed fuel under irradiation in BN-800. Verification calculations were performed for fuel elements irradiated in BN-600 under close to nominal conditions. Attention was focused mainly on the factors playing an important role in their serviceability: swelling, creep, corrosion behavior of cladding, temperature distribution, gas-release, and degree of structural reformation of the fuel core.The growing strain on the world energy market is stimulating many countries, especially developing countries, to consider nuclear energy as a promising, rapidly growing, energy supply sector. In this context, the decisions made in our country concerning the development of the nuclear energy-industrial complex and nuclear power are timely. In order for nuclear power to secure world energy security, nuclear capacities must increase rapidly and supply nuclear power with nuclear fuel resources over the long term. The Russian nuclear sector is poised to rapidly build VVER reactors over the next few decades in our country and abroad. Fuel supplies for reactors are of no concern up to the middle of the 21st century, using explored and predicted resources of economically acceptable uranium. However, if the entire service life of the reactors built and further growth of nuclear power are taken into account, fuel adequacy for a conventional open fuel cycle cannot be guaranteed. Additional fuel sources must be prepared in order to reduce the risk. Bringing 238 U and 232 Th into the fuel cycle makes the fuel component almost insensitive to the cost of the natural raw material for any imaginable scales. The path toward a radical solution of largescale nuclear power must include fast reactors for expanded breeding of nuclear fuel. Then reprocessing spent nuclear fuel and closure of the fuel cycle using the plutonium produced in the fast reactors will make it possible to fuel fast and thermal reactors. The plutonium accumulated in thermal reactors will be used for the initial fueling of fast reactors [1].To implement this strategy with respect to expanded breeding of fuel, stringent requirements are imposed on the fuel cycle closure parameters, the arrangement of the core and blanket, and especially the fuel [2]. A step toward commercial implementation of this technology is the construction at the Beloyarskaya nuclear power plant of the BN-800 reactor, which is intended for developing a closed fuel cycle on mixed fuel. Mixed fuel is now the best prepared variant for this initial variant. The problem of supplying fuel for the BN-800 under construction, which includes searching for an acceptable commercialtechnological solution to fabrication, shipment, and validation of fuel serviceability, is now being solved. Two variants are being considered: pelleted and vibrationally compacted fuel.The variant using vibrationally compacted fuel is being examined for BN-600 and BN-800, which is under construction. This choice is neither unique nor ...