Semi-empirical and semi-quantitative lightweight shielding design method

The lightweight shielding design of small reactors is a popular research topic. Based on a small helium-xenon-cooled solid reactor, the effects of neutron and photon shielding sequence and the number of shielding layers on the radiation dose were first studied. It was found that when photons were shielded first and the number of shielding layers was odd, the radiation dose could be significantly reduced. To reduce the weight of the shielding body, the relative thickness of the shielding layers was optimized using the genetic algorithm. The optimized scheme can reduce the radiation dose by up to 57% and reduce the weight by 11.84%. To determine the total thickness of the shielding layers and avoid the local optimal solution of the genetic algorithm, a series of formulas that describes the relationship between the total thickness and the radiation dose was developed through large-scale calculations. A semi-empirical and semi-quantitative lightweight shielding design method is proposed to integrate the above shielding optimization method that verified by the Monte Carlo method. Finally, a code, SDIC1.0, was developed to achieve the optimized lightweight shielding design for small reactors. It was verified that the difference between the SDIC1.0 and the RMC code is approximately 10% and that the computation time is shortened by 6.3 times.