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OSTP memo guides space nuclear plan
A White House Office of Science and Technology Policy (OSTP) memorandum released on Tuesday guides NASA, the Department of Energy, and the Department of Defense on their roles in deploying near-term space nuclear power.
This follows a series of NASA announcements last month—driven by the executive order “Ensuring American Space Superiority,” issued by Trump in December—including an ambitious timeline for establishing a moon base, which would rely on fission surface power (FSP) to survive the long lunar night at the moon’s south pole, and plans for a nuclear electric propulsion (NEP) rocket to be launched in 2028.
Hoang Hai Nguyen, Jun Nishiyama, Toru Obara
Nuclear Science and Engineering | Volume 194 | Number 12 | December 2020 | Pages 1128-1142
Technical Paper | doi.org/10.1080/00295639.2020.1775433
Articles are hosted by Taylor and Francis Online.
The CANDLE (Constant Axial shape of Neutron flux, nuclide densities and power shape During Life of Energy production) reactor concept was proposed to overcome the disadvantages of current reactor technologies. In this study, a Monte Carlo–based procedure is developed for quantitative comparison of burnup performance and neutronic characteristics between lead bismuth eutectic (LBE)–cooled and sodium-cooled CANDLE reactors to demonstrate the possibility of using sodium coolant in a small CANDLE burning reactor. In this procedure, a neutron transport equation is solved using the MVP code with the JENDL-4.0 library, and the burnup calculation is solved using the MVP-BURN code with the detailed burnup chain. To simulate the fuel-shuffling process, an auxiliary code was developed using Python. The results show that for the same fuel pin design and core volume, changing the coolant from LBE to sodium reduced the keff by 2.3% and the average discharge burnup by 15.6%, due to the softer neutron spectrum and larger neutron leakage fraction. It would be necessary to increase the fuel volume and core radius approximately 38% and 17%, respectively, for criticality in a sodium-cooled CANDLE core.
