Open Access

ARTICLE

An Innovative HCCB Blanket with Casing Structure for Compact Fusion Reactor

Xiaoyong Wang¹, Shen Qu^1,*, Ziqiang Zhao², Fengchao Zhao¹, Qixiang Cao¹, Long Zhang¹
1 Division of Blanket and Fuel Technology, Institute of Fusion Technology, Southwestern Institute of Physics, Chengdu, China
2 Division of General Technology, Fusion Engineering Design Institute, China Fusion Energy Corporation, Shanghai, China
* Corresponding Author: Shen Qu. Email:
(This article belongs to the Special Issue: Neutronic and Thermal-Hydraulic Analysis of Advanced Nuclear Reactors)

Energy Engineering https://doi.org/10.32604/ee.2026.084990

Received 03 May 2026; Accepted 27 May 2026; Published online 22 June 2026

Abstract

The blanket system for a compact fusion demonstration reactor (DEMO) is subject to particularly stringent requirements in terms of physical performance, reliability, and engineering feasibility. To address these challenges, this paper proposes an innovative helium-cooled ceramic breeder (HCCB) blanket concept based on a concentric casing structure. The core unit of this design is a standardized concentric casing: the inner tube encapsulates the ceramic breeder (Li₄SiO₄), the annular gap serves as the helium coolant flow channel, and the outer region is packed with a neutron multiplier (Be). This architecture is intended to simplify manufacturing, reduce the number of welds, and improve neutron economy and spatial utilization by relocating coolant manifolds to the blanket extremities. Furthermore, an independent modular grid system is introduced to achieve functional decoupling between normal operation support and accidental pressurization (e.g., in-box loss-of-coolant accident, LOCA). This paper systematically describes the overall architecture of the blanket and presents integrated neutronics, thermal-hydraulic, and preliminary structural performance assessments. The neutronics analysis yields a system tritium breeding ratio (TBR) of approximately 1.2, satisfying the self-sufficiency requirement. Local analysis of an inboard equatorial blanket segment indicates that the operating temperatures of both structural and functional materials remain within established safety limits. The casing tubes, first wall, and box structure meet relevant structural design criteria (SDC-IC) under both normal operating loads and accidental conditions. The results demonstrate that the proposed casing-based blanket concept holds significant potential in terms of tritium breeding performance, thermal management capability, and structural safety, providing a novel reference for future fusion reactor blanket design that synergistically combines high performance with high engineering realizability.

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Keywords

DEMO; first wall; HCCB blanket; thermal-hydraulic; TBR

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