HELCZA—High heat flux test facility for testing ITER EU first wall components

doi:10.1016/j.fusengdes.2017.03.059

Fusion Engineering and Design

Volume 124, November 2017, Pages 187-190

https://doi.org/10.1016/j.fusengdes.2017.03.059 Get rights and content

Highlights

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High heat flux test facility HELCZA for testing full-scale ITER plasma facing components.
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Electron beam based heat flux cyclic loading.
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Testing Beryllium containing first wall panels, divertor inner vertical target and ICRF antenna screens.

Abstract

The ITER first wall panels are exposed directly to thermonuclear plasma and must extract heat loads of approximately 2 MW/m² (normal heat flux) to 4.7 MW/m² (enhanced heat flux). The panels are qualified through high heat flux cyclic testing before installation in ITER. Initially, the first wall panel prototypes will undergo full-power tests, they will be followed by the pre-series panels and finally the series ones. The experimental complex HELCZA (High Energy Load CZech Assembly) has been completed and is currently in the commissioning phase. HELCZA shall be optimised to provide a cyclic heating of the ITER EU first wall panels with a heat flux in the multi-MW/m² range using an 800 kW electron beam. On a reduced area it is possible to reach GW/m² scale. Total available test area in HELCZA is 4 m² depending on the experimental setup. Operational conditions of the HELCZA facility enable the temperature of the cooling water to be set between 25 °C and 320 °C, within a pressure range up to 15 MPa. The cooling system provides an optimal flow rate up to 40 m³/h independent of the pressure.

Introduction

The plasma-facing components comprising the first wall (FW) and divertor targets will be the most heat-loaded components of ITER. Among other challenges, they must accommodate a high heat flux from the plasma. The ITER FW panels must extract heat loads of about 2 MW/m² (normal heat flux design) and 4.7 MW/m² (enhanced heat flux design). The panels will be qualified through high heat flux cyclic testing in a dedicated facility before their installation in ITER [1].

In Europe there exists several electron beam facilities for cyclic heat load testing. FE200 in France [2] for mock-up testing, JUDITH II in Germany [3] for semi-prototypes of FW panels testing, IDTF in Russia [4] for full scale divertor component testing are all electron-beam based test facilities. Furthermore, some other smaller facilities are or have been in operation [5], [6]. However, their characteristics do not allow full-scale FW testing, which is the primary goal of HELCZA.

The experimental complex HELCZA is dedicated to the series of acceptance tests of the FW panels, divertor inner vertical targets and ICRF antenna screens, which are part of the EU contribution to the ITER project. The FW panel prototypes will undergo full-power tests followed by the pre-series and finally the series panels tests. HELCZA has recently been completed and is now in its commissioning phase.

Section snippets

Test facility description

HELCZA is an electron-beam based test facility for cyclic high heat flux loading of plasma-facing components, thermohydraulic testing with preheated water and infrared thermography. The device is equipped with an electron beam gun with a maximum output power of 800 kW. At the maximum acceleration voltage of 55 kV the electron current exceeds 14 A. HELCZA is primarily intended for full-size testing of the ITER FW modules, divertor inner vertical targets and ICRF antenna screens with a surface area

Main objectives of HELCZA for ITER qualification tests

The objective of the tests is high heat flux cyclic loading of the plasma-facing full-scale FW components and their qualification for their later use in the ITER tokamak. The basic criterion for evaluation of the high heat flux testing is the absorbed heat flux by the coolant of the sample. The absorbed heat flux is measured by calorimetry across the inlet and outlet pipes of the sample connected to the high-pressure cooling branch of the test facility. The prescribed heat flux corresponds to

Conclusion and perspectives

The experimental complex HELCZA has reached the commissioning stage. The goal of the commissioning is to prove that all projected parameters and all requirements for the ITER EU FW panel testing, divertor inner vertical target testing and ICRF antenna screen testing are met. The very first results from the facility operation have already been obtained [10], the sample irradiated during first phase of commissioning is depicted in Fig. 3. The end of the commissioning is expected by 2017.

Acknowledgments

The opinions expressed herein are those of Centrum výzkumu Řež s.r.o. only and do not represent Fusion for Energy's official position.

This work has been supported by the SUSEN Project CZ.1.05/2.1.00/03.0108 realized in the framework of the European Regional Development Fund (ERDF).

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There are more references available in the full text version of this article.

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HELCZA—High heat flux test facility for testing ITER EU first wall components

Highlights

Abstract

Introduction

Section snippets

Test facility description

Main objectives of HELCZA for ITER qualification tests

Conclusion and perspectives

Acknowledgments

Fusion Eng. Des.

Fusion Eng. Des.

Fusion Eng. Des.

Fusion Eng. Des.

Fusion Eng. Des.