The Estimation And Visualization Of Radiation Field For The Decommissioning Source Term Of PWR

With the development of nuclear, from military to civilian using,for example, rapidly development in nuclear power. currently there are 442 nuclear power units are running, 66 nuclear power units under construction, which transported nuclear units power share in the world total electricity 16%. In the occasion of large-scale utilization of nuclear energy, a large number of early nuclear facilities in the nuclear industry, including military facilities, research reactors and nuclear power reactor, model piles, design life cycle has been reached, are decommissioning or decommissioned. According to IAEA estimates that approximately 2800 nuclear facilities around the world need to be decommissioned in the coming decades.Using virtual reality simulation technology, 3D-CAD, radiation geometry and visualization technology, to simulate the formulated programme of nuclear decommissioning, research whether decommissioning equipment compatibility or not, research whether can achieve the overall performance objectives research whether the device meets the safety and reliability requirements or not, research decommissioning equipment repair and maintenance, to make early detection and to solve problems, reducing the number of accidents. Using virtual reality technology to simulation nuclear facility decommissioning is an inevitable trend.After decades of development, overseas through practice and research work on the basis of the decommissioning of nuclear facilities, form a set of sources estimate analysis methods, verified through a large number of nuclear installations practical activities, and developed a series of sources estimate analysis and visualization systems. At present, It lack of decommissioning of practice success story and corresponding decommissioning sources estimate analysis program and its source visualization system.According to the actual situation of Qinshan reactor, pin-by-pin neutron transport calculation model for whole core was set up by monte carlo codes.Based on geometric parameters, material parameters, neutron fluence rate distribution of structure parts, and assumed reactor power history, using burnup calculation codes,calculated the neutron activation products as estimation results of source term after shutdown, and analyzed 3D radiation field visualized model of source term, the simulation results consistent with the theoretical analysis. This research is important and basic work for the establishment of Qinshan nuclear power plant decommissioning technology security verification and virtual simulation platform.