Investigation of reflection properties of applied reflectors for thermal neutrons by considering the albedo and spectral shift

Azimkhani, S.; Zolfagharpour, Farhad; Ziaie, Farhood

doi:10.1016/j.pnucene.2017.06.011

Cited by 5 publications

(3 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To handle this safety issue, a core shutdown criterion with k eff less than 0.95 has been proposed for a lithium heat pipe-cooled reactor according to the safety analysis of an accident of submersion [25]. This criterion has been adopted by many follow-up studies [25,47,48], and it is hence taken for the safety design of the HX-micro-MSR.…”

Section: Burnup Analysis and Control Drum Designmentioning

confidence: 99%

Conceptual Design of a Novel Megawatt Molten Salt Reactor Cooled by He-Xe Gas

Zhao,

Wu,

Chen

et al. 2023

International Journal of Energy Research

View full text Add to dashboard Cite

He-Xe gas-cooled micro-molten salt reactor (HX-micro-MSR) is a novel reactor concept that integrates the technologies of molten salt reactor and closed Brayton cycle (CBC), which has a more compact structure compared with the other types of micro-MSRs. The reactor system probed in this paper has a thermal power of 2.5 MWth and consists of the core, fission gas collecting container, and CBC system. The He-Xe gas flows through the coolant channels in the core to transfer the nuclear heat to the CBC for electricity production. To withstand the large pressure difference between the He-Xe gas coolant (7 MPa) and molten salt (nearly atmospheric pressure), the sizes and wall thickness of coolant channels are analyzed and optimized to be 8 mm and 0.5 mm, respectively. In total, 1050 coolant channels are regularly arranged in the core to effectively remove the nuclear heat. The enrichment of U-235 in the fuel UF4 is determined to be 61% to meet the burnup goal of 5 years. To minimize the neutron leakage, the thickness of reflector is selected to be 23 cm. Six control drums with the diameter in 10.5 cm and neutron absorber layer thickness in 1 cm are symmetrically placed in the reflector to realize reactivity control under both normal and accident conditions. Radiation shield is designed and analyzed by varying the thickness of multiple shielding layers, and it is found that a combination of W layer in 14 cm and Mg(BH4)2 layer in 56 cm can satisfy the criterion of radiation dose (<1 mSv/h). The total weight of HX-micro-MSR is estimated to be 35 tonnes and falls into the acceptable range.

show abstract

Section: Burnup Analysis and Control Drum Designmentioning

confidence: 99%

Conceptual Design of a Novel Megawatt Molten Salt Reactor Cooled by He-Xe Gas

Zhao,

Wu,

Chen

et al. 2023

International Journal of Energy Research

View full text Add to dashboard Cite

show abstract

“…The principle of selecting reflector materials is that the material has large neutron scattering cross section as well as small absorption cross section [21][22][23]. Consequently, we selected graphite, beryllium, polyethylene, paraffin and lead as the reflector material, and then simulated and compared the corresponding thermal neutron albedo.…”

Section: Reflector Materials and Structurementioning

confidence: 99%

“…Relying on the inherent advantages of open source software, user activity of GEANT4 has always been high, and many physical processes can be improved and corrected in time. In this work, the simulations were based on the version 10.04 of GEANT4 using the G4HadronPhysics QGSP_BIC_HP model and accurate neutron reaction cross-section that are taken from the ENDF evaluated data library [21]. Furthermore, we used the NeutronHPThermalScattering model to deal with the elastic scattering of thermal neutrons.…”

Section: Reflector Materials and Structurementioning

confidence: 99%

Simulation-based optimization of a thermal neutron detector with SERS method

Chai¹,

Wang²,

Chang³

et al. 2021

J. Inst.

View full text Add to dashboard Cite

A Monte Carlo simulation-based optimization of a SERS-based thermal neutron detector is aimed at improving detection efficiency for thermal neutrons. The moderator and collimator have been designed for a 241Am-9Be source to maximize the thermal neutrons flux in the irradiation area. Simulated thermal neutron detection efficiency can be increased to approximately 50.5% when polyethylene is added as neutron reflector and 10B enriched 4-MPBA is used. With Monte Carlo software GEANT4, the SERS-based thermal neutron detector has been proven to have almost no effect on original thermal neutron flux as well as the distribution and could be used for thermal neutron detection accurately.

show abstract