8–12 Jun 2026
Karlsruhe Institute of Technology, Campus north
Europe/Berlin timezone

Preliminary design and assessment of a Fusion-Fission Hybrid TBM for Tokamak Devices

10 Jun 2026, 11:30
20m
Online

Online

Oral Facility nuclear design challenges Fusion Reactor Design and Safety

Speaker

xilong Tong (University of Science and Technology of China)

Description

Fusion-fission hybrid reactors represent a promising pathway for future energy supply. However, the feasibility of this technological route has yet to be validated through a Test Blanket Module (TBM)-scale experiment, and comprehensive theoretical designs are still required to guide such experimental efforts. In this study, an innovative TBM design containing spent fuel from Pressurized Water Reactors was developed for integration into fusion devices. The design was comprehensively assessed using Monte Carlo methods. The analysis focused on key economic performance indicators, including the Tritium Breeding Ratio (TBR), multiplication of nuclear heat deposition, decay heat, and transmutation rates of major actinides, as well as critical safety parameters such as displacement per atom, the effective multiplication factor, nuclear heat removal, gas production rate, and fission product containment.
Results show that introducing spent fuel increases the overall neutron flux in the TBM. An optimized layout improves irradiation uniformity of the tritium breeder material, which in turn enhances its economic potential. At an appropriate volume fraction, spent fuel raises the TBR by nearly 2% relative to the design without spent fuel. The ratio of total nuclear heat deposition in the TBM to the total fusion energy entering the TBM is 458. Safety analyses confirm that the spent fuel remains deeply subcritical under all operating conditions, with a maximum keff below 0.2. The additional irradiation damage stays within acceptable limits for structural materials. Along with these performance improvements, the TBM design provides sufficient cooling space to safely remove nuclear heat generated during operation and decay heat after shutdown. Furthermore, at a fusion power of 10 MW, the fuel cladding effectively retains fission products and prevents their release. In summary, this study proposes a TBM design suitable for experimental validation in fusion–fission hybrid reactors, which is expected to accelerate the engineering application of this technology.

Formatted abstract uploaded? Done.

Author

xilong Tong (University of Science and Technology of China)

Co-authors

Dr Shanliang Zhang (Hefei Institute of Physical Sciences, Chinese Academy of Sciences) Dr Xiaokang Zhang (Hefei Institute of Physical Sciences, Chinese Academy of Sciences)

Presentation materials