Aiming at understanding thermo-mechanical loads in the first wall of DEMO: Stress–strain evolution in a Eurofer-tungsten test component featuring a functionally graded interlayer

0492145 - ÚFP 2019 RIV NL eng J - Článek v odborném periodiku
Heuer, S. - Weber, T. - Pintsuk, G. - Coenen, J.W. - Matějíček, Jiří - Linsmeier, Ch.
Aiming at understanding thermo-mechanical loads in the first wall of DEMO: Stress–strain evolution in a Eurofer-tungsten test component featuring a functionally graded interlayer.
Fusion Engineering and Design. Roč. 135, October (2018), s. 141-153. ISSN 0920-3796. E-ISSN 1873-7196
Grant CEP: GA ČR(CZ) GA17-23154S
GRANT EU: European Commission(XE) 633053 - EUROfusion
Institucionální podpora: RVO:61389021
Klíčová slova: Nuclear fusion * DEMO * First wall * Finite Element Analysis * Functionally graded materials (FGM) * Fe/W
Obor OECD: Composites (including laminates, reinforced plastics, cermets, combined natural and synthetic fibre fabrics
Impakt faktor: 1.457, rok: 2018
https://www.sciencedirect.com/science/article/pii/S0920379618305660?via%3Dihub

For the future fusion demonstration power plant, DEMO, several blanket designs are currently under consideration.
Despite geometric and operational differences, all designs suggest a first wall (FW), in which tungsten (W) armour is joined to a structure made of Reduced Activation Ferritic Martensitic (RAFM) steel. In thermomechanical analyses of breeding blankets, this joint has received limited attention. In order to provide a basis for better understanding of thermally induced stresses and strains in the FW, the thermo-mechanical behaviour of a water-cooled test component is explored in the current contribution. The model aims at providing a simple geometry that allows straightforward comparison of numerical and experimental results, while trying to keep boundary conditions as realistic as possible. A test component with direct RAFM steel-W joint, and a test component with a stress-redistributing, functionally graded RAFM steel/W interlayer in the joint is considered in the current contribution. The analyses take production- and operation-related loads into account. Following a detailed analysis of the evolution of stress components and strain in the model, a parameter study with respect to geometric specifications and loads is presented.
The analyses show that, even in a small test component, a direct RAFM steel-W joint causes enormous plastic deformation. The implementation of a functionally graded interlayer reduces stresses and strains significantly, but vertical normal stresses at the joint's circumference remain considerable. With the component geometry considered here, the graded interlayer should be at least 1mm thick and contain 4 sublayers to appropriately redistribute stresses. Beyond a component width of 14 mm, stresses increase strongly, which may pose a risk to the applicability of large-scale FW components, too.
Trvalý link: http://hdl.handle.net/11104/0287860