Majid Zamani; Mohsen Shayesteh
Abstract
Using the experimental data in nuclear computing to verify the calculation methods and tools based on numerical and statistical methods has many benefits such as illustrating the quality, ensuring the capabilities, and computer codes validating. Simulation by computer tools is also applicable in the ...
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Using the experimental data in nuclear computing to verify the calculation methods and tools based on numerical and statistical methods has many benefits such as illustrating the quality, ensuring the capabilities, and computer codes validating. Simulation by computer tools is also applicable in the safety analysis of research reactors. In this research, the computer tool (MCNPX 2.7.0: 2011) was verified against the experimental data of neutron flux and spectrum on the sample position of the Tehran Research Reactor (TRR) neutron imaging system by the neutron activation method. To determine the benchmark specifications, the simulation of the system was done at the first step by considering a well-defined facility geometric, material specification and reactor core configuration, fuel elements, and radiation facility (beam tubes and collimator, reactor core, and neutron imaging components). Then the flux and neutron spectrum at the sample position were calculated. In the second step, a set of In (bare and covered by cd) and Au foils and a set of Au, Ni, Ti, and Zr, were placed and exposed almost in front of the reactor E beam tube. The neutron energy spectrum was unfolded by calculating the saturation activity of each foil by SAND-II code, and the neutron flux was calculated. A comparison of the results obtained in two steps shows a relatively good and acceptable agreement (Max. 30% deviation) between the flux and the shape of the flux profile obtained from calculations and experimental data.
Mehrdad Shamsinasab; Mansour Asgari; Mahdi Eshghi
Abstract
Nuclear-pumped lasers (NPL) are lasers that excite the active laser environment caused by nuclear reaction. Such lasers need ionizing radiation shielding for mixed neutron and gamma fields. In this work, a shielding system for NPL was designed which using 10B(n,α)7Li. In this simulation, we have ...
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Nuclear-pumped lasers (NPL) are lasers that excite the active laser environment caused by nuclear reaction. Such lasers need ionizing radiation shielding for mixed neutron and gamma fields. In this work, a shielding system for NPL was designed which using 10B(n,α)7Li. In this simulation, we have used MCNPX 2.6.0 Monte Carlo code and the thermal neutron flux as 1×1016 n.cm-2.s-1 for excitation reaction. Such a large neutron flux can be obtained from a reactor source or a heavy ion accelerator. For this work, 10B fuel is covered on the surface of a rectangular cube aluminum shell by using the Monte Carlo method. In the design of the shielding, combinations with different materials have been used with various arrangements in three layers. According to the simulation, the arrangement of Fe2-B-BPE-Pb is a suitable protection compound for such lasers.
