Design and preliminary analyses of the new Water Cooled Lithium Lead TBM for ITER

doi:10.1016/j.fusengdes.2020.111921

Fusion Engineering and Design

Volume 160, November 2020, 111921

https://doi.org/10.1016/j.fusengdes.2020.111921 Get rights and content

Abstract

In the European strategy, DEMO is the intermediate step between ITER and a commercial fusion power plant. In this framework, one of the goal of DEMO is to be a Breeding Blanket test facility. The Breeding Blanket, which is not present in ITER, is one of the key components for the future deployment of nuclear fusion electricity as it accomplishes the functions of tritium breeding and nuclear to thermal power conversion.

Due to time constraints lead by the construction schedule of DEMO, a new strategy to consider in DEMO a “driver” Breeding Blanket that needs limited technological extrapolation has been chosen, while “advanced” Breeding Blanket concepts will be tested in the next phases. In this context, ITER will allow to test technologies to provide relevant contributions in terms of Return of eXperience to the DEMO “driver” Breeding Blanket project by the mean of Test Blanket Modules (TBM) to be installed in different ITER Vacuum Vessel Ports.

Among the possible “driver” Breeding Blanket, the Water Cooled Lithium Lead (WCLL) concept comes out. In this framework, a realignment of the DEMO Breeding Blanket and TBM programs has started in 2017, leading to a new TBM development relevant of the DEMO WCLL BB. The WCLL TBM is therefore an essential component in ITER that will provide crucial information for the development of the DEMO “driver” blanket.

This paper aims at presenting the development process and design status of WCLL TBM. After recalling the main features of the WCLL TBM, conceptual design analyses are presented and discussed.

Introduction

In the European strategy, DEMO is the intermediate step between ITER and a commercial fusion power plant [1]. In this framework, one of the goal of DEMO is to be a Breeding Blanket (BB) test facility. The Breeding Blanket, which is not present in ITER, is one of the key components for the future deployment of nuclear fusion electricity as it accomplishes the functions of tritium breeding and nuclear to thermal power conversion.

Among the possible “driver” Breeding Blanket, the Water Cooled Lithium Lead (WCLL) concept stands out as a more near-term technological option. A realignment of the DEMO Breeding Blanket and TBM programs has started in 2017 [2], leading to a new TBM development relevant of the DEMO WCLL BB. The WCLL TBM is therefore an essential component in ITER that will provide crucial information for the development of the DEMO “driver” blanket.

This paper presents the development process and design status of WCLL TBM. After recalling the main features of the WCLL TBM, conceptual design analyses are presented and discussed.

Section snippets

WCLL TBM design description

The WCLL TBM, which will be installed in the ITER Equatorial Port #16, is designed following the same overall technological features and thermo-hydraulic parameters as the European DEMO WCLL BB described in [3] such as Reduced Activation Ferritic-Martensitic (RAFM) Eurofer-97 steel as structural material, slowly flowing Pb–15.7Li liquid metal as tritium breeder and neutron multiplier, and water pressurized at 15.5 MPa with a target value of inlet/outlet temperatures of 295 °C / 328 °C as

Preliminary design analysis

Several thermal and mechanical analyses under the most relevant load combinations have been carried out in order to select the best design configuration and to prove that the functional and design requirements are met. However, the results consist only in preliminary outputs that will be further developed and detailed during studies and activities which will have to be carried out in view of the WCLL-TBS Conceptual Design Review, planned for mid-2020. Moreover, only the results related to the

Conclusions

This paper presents the design of the new Water Cooled Lithium Lead (WCLL) TBM for ITER. Mechanical as well as coolant and breeder paths are described. Preliminary thermal and mechanical calculation have been carried out with finite element method, showing a thermal behavior in steady state Normal Operating condition, and a mechanical behavior in case of in-box Loss Of Coolant Accident compliant with the material properties and RCC-MRx criteria.

However, optimization such as mass flow

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission.

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Design and preliminary analyses of the new Water Cooled Lithium Lead TBM for ITER

Abstract

Introduction

Section snippets

WCLL TBM design description

Preliminary design analysis

Conclusions

Declaration of Competing Interest

Acknowledgments

Fusion Electricity – a Roadmap to the Realization of Fusion Energy

An overview of the EU breeding blanket design strategy as an integral part of the DEMO design effort

Fusion Eng. Des.

HCLL TBM design status and development

Fusion Eng. Des.

Neutronic and photonic analysis of the water-cooled Pb-17Li test blanket module for ITER-FEAT

Fusion Eng. Des.