| The Spallation Neutron Source is a huge scientific research devices and a multi-disciplinary services platform. China Spallation Neutron Source (CSNS) is one of most important scientific and technological infrastructure in China which is currently under construction, located in Da Lang Town, Dongguan City, Guangdong Province. It will provide a basic research and high-tech development platform for physics, chemistry, life sciences, biology, materials, nanotechnology and many leading edge of other subjects.In this article, according to Target Station and Spectrometer Volume of the China Spallation Neutron Source Preliminary Design Report, the general Monte Carlo N-Particle transport code version5(MCNP5) and its extension code MCNPX were used to model, simulate and calculate neutrons production, transportation and absorption in the major components of CSNS target station.Firstly, the processes of proton bombardment of tungsten metal target and the spallation reaction of high-energy protons with tungsten nuclides were simulated. The average neutron yield and neutron flux of the target container surface were calculated. Next, based on the target model stated above, the moderators and the reflector were added to the model, and the moderators’output neutron energy spectrums were obtained. Finally, information based on simulations was analysed and effect of poison’s location and thickness on output neutron energy spectrums were simulated and studied. The result shows that placing the poison in the center of decoupled poisoned moderator with a deviation of5mm to the downstream window can optimize the design and the thickness of the poison has little influence on output neutron energy spectrums.During all the simulating, massive calculation was taken by using MCNP5/MCNPX, and the results were proved credible. This article could provide a reference for those students who interested in particle transporting using Monte Carlo method and grand nuclear research devices. |
PDF Full Text Request