The Plasma-Facing Materials of Tokamak Thermonuclear Reactors: Requirements, Thermal Stabilization, and Tests (a Review)

• Published in: Thermal engineering 2021-03, Vol.68 (3), p.185-200
• Main Authors: Van Oost, G., Dedov, A. V., Budaev, V. P.
• Format: Article
• Language: English
• Subjects: Chambers; Convection cooling; Cooling systems; Energy spectra; Engineering; Engineering Thermodynamics; Fluid dynamics; Heat and Mass Transfer; Heat and Mass Transfer and Properties of Working Fluids and Materials; Heat transfer; Liquid metal cooled reactors; Loads (forces); Materials selection; Nuclear electric power generation; Nuclear power plants; Nuclear reactions; Nuclear reactors; Parameters; Plasma; Radiation dosage; Saline solutions; Swirling; Thermal protection; Thermonuclear reactions; Tungsten; Turbulent flow; Water flow
• ISSN: 0040-6015; 1555-6301
• DOI: 10.1134/S0040601521030095

— The results from experimental investigations of chamber internal parts and plasma-facing materials proposed for use in a thermonuclear reactor are reviewed. The thermonuclear reactor internals will experience various heat loads connected with temperature gradients and local exposure dose with the nuclear reaction neutron energy spectrum. The lifetime of the systems will depend on the resistance of materials to neutron and heat loads. Assurance of heat removal is one of serious problems to be solved in implementing a thermonuclear power plant. The components can be cooled either by gas or liquid, including salt solutions and liquid metals. The parameters of coolants, heat-transfer systems, and cooling systems will take values that are still not attainable as of yet. The variety of available design elaborations suggested in the Russian and foreign projects must be substantiated in terms of heat transfer. The parameters of heat and neutron loads will govern the choice of materials for the thermonuclear reactor systems. The international thermonuclear experimental reactor (ITER), which is under construction, will be built using structures, materials, and technologies that have passed the main tests. The ITER cooling systems will operate with forced single-phase convection of turbulent water flow; the heat transfer will be intensified by using inner finning and flow swirling. The thermal protection lining of the plasma-facing chamber’s internal parts in the zones of the highest plasma and heat load will be made of tungsten. In elaborating the design of the next-generation demonstration reactor (DEMO), it will be necessary to additionally develop the blanket construction technologies and solve the problem of converting heat into electricity. The materials for the DEMO reactor must be selected with due regard to the high dose of their irradiation by neutrons with the thermonuclear reaction energy spectrum and critically high heat loads experienced by the plasma-facing chamber’s internals. It will be necessary to develop and test new materials for constructing the DEMO thermonuclear reactor and solve matters concerned with their commercial-scale manufacture.