Keywords: MCNP5, Monte Carlo simulation, irradiation positions, TRIGA, neutron spectrum, neutron flux distribution, research reactors, design of experiments, reactor safety, nuclear energy, nuclear power
Monte Carlo characterisation of irradiation positions of the CENM TRIGA MARK II research reactor using MCNP5
The knowledge of neutron flux distribution in different parts of the research reactor is very important both for the design of experiments and for the reactor safety. Knowing the neutron flux profiles, reactor operators can optimise the irradiation conditions and select the positions most adaptable to the desired applications. Transport calculations can often give useful information about the irradiation field characteristics. However, for complicated geometries, only the Monte Carlo calculations are able to give a reliable characterisation. In this work, calculations were performed to predict neutron flux profile at different locations in the CENM TRIGA MARK II reactor. A detailed MCNP5 model of the reactor was used. The calculations show that neutron energy spectrum depends strongly on the position in the reactor. They also show that the maximum flux decreases by a factor of 3.75 from core centre to the pneumatic transfer system in the outer ring of the core. Further simulations demonstrate that neutron energy distribution is greatly affected by materials in which they diffuse.