Thermal-stress analysis of IFMIF target back-wall made of reduced-activation ferritic steel and austenitic stainless steel

Ida, Mizuho; Chida, Teruo; Furuya, Kazuyuki*; Wakai, Eiichi; Nakamura, Hiroo; Sugimoto, Masayoshi

Journal of Nuclear Materials, 386-388, p.987 - 990, 2009/04

https://doi.org/10.1016/j.jnucmat.2008.12.272

To clarify IFMIF target back-wall structures and materials with acceptable thermal-stress and deformation due to nuclear heating during the accelerator operation, thermal-stress analysis was done using a code ABAQUS and data of nuclear heating. Two types of back-wall were estimated. One is made of only 316L, and the other is made of 316L at its circumference and F82H a RAF steel at center. Effects of stress-mitigation structure with thickness 2-8 mm, and beam heat loads of 10-100% were estimated. As a result, thermal-stress in the latter back-wall is acceptable level less than 328 MPa for 316L and 455 MPa for F82H even under full heat load, if thickness of the stress-mitigation part is more than 5 mm. On the contrary, thermal-stress in the former is not acceptable. In preliminary tensile tests on dissimilar welding (316L-F82H) specimen, the fracture was occurred in base metal of 316L. Therefore, this welding is expected to be employed as the back-wall.

Review of JAEA activities on the IFMIF liquid lithium target in FY2006

Ida, Mizuho; Nakamura, Hiroo; Chida, Teruo*; Miyashita, Makoto; Furuya, Kazuyuki*; Yoshida, Eiichi; Hirakawa, Yasushi; Miyake, Osamu; Hirabayashi, Masaru; Ara, Kuniaki; et al.

JAEA-Review 2008-008, 38 Pages, 2008/03

JAEA-Review-2008-008.pdf:9.37MB

Engineering Validation Design and Engineering Design Activity (EVEDA) of the International Fusion Materials Irradiation Facility (IFMIF) is under going. IFMIF is an accelerator-based Deuterium-Lithium (D-Li) neutron source to produce intense high energy neutrons and a sufficient irradiation volume for testing candidate materials for fusion reactors. To realize such a condition, 40 MeV deuteron beam with a current of 250 mA is injected into high speed liquid Li flow with a speed of 20 m/s. In target system, nuclear heating due to neutron causes thermal stress especially on a back-wall of the target assembly. In addition, radioactive species such as beryllium-7, tritium and activated corrosion products are generated. In this report, thermal stress analyses of the back-wall, mechanical tests on weld specimen made of the back-wall material, estimations of beryllium-7 behavior and worker dose at the IFMIF Li loop and consideration on major EVEDA tasks are summarized.

Thermo-structural analysis of backwall in IFMIF lithium target, 2

Chida, Teruo; Ida, Mizuho; Nakamura, Hiroo; Sato, Toru*; Sugimoto, Masayoshi

JAEA-Technology 2007-048, 40 Pages, 2007/08

JAEA-Technology-2007-048.pdf:5.42MB

This report describes results of thermo-structural analysis of a backwall in international fusion material irradiation facilities (IFMIF) lithium target preformed during FY2007. The IFMIF is an accelerator-based intense neutron source for testing candidate materials for fusion reactors. Since the backwall is operating under a severe neutron irradiation of 50 dpa/year and a maximum nuclear heating rate of 25 W/cm, thermo-structural design is one of critical issues in a target design. Since previous model included only the backwall, a model including a part of target assembly is applied. In this analysis, three models were calculated. First model is a basic geometry adding a part of the target assembly to the backwall. Second model is a modified geometry which has a thin backwall. In a third model, a lip seal with a stress mitigation structure was applied to the second model. Calculation results showed that, in the third model, a thermal stress at a center of the backwall was 146 MPa below a permissible stress of F82H (455MPa: an yield strength at 300C) and maximum stress was 286 MPa below a permissible stress of SUS316L (328MPa: 3Sm value at 300C). These results showed a prospect of the present backwall configuration.

Review of JAEA activities on the IFMIF liquid lithium target in FY2005

Ida, Mizuho; Nakamura, Hiroo; Chida, Teruo; Sugimoto, Masayoshi

JAEA-Review 2006-009, 28 Pages, 2006/03

JAEA-Review-2006-009.pdf:3.95MB

The International Fusion Materials Irradiation Facility (IFMIF) is being jointly planned to provide an accelerator-based Deuterium-Lithium (D-Li) neutron source to produce intense high energy neutrons (2 MW/m) up to 200 dpa and a sufficient irradiation volume (500 cm) for testing candidate materials and components up to about a full lifetime of their anticipated use in ITER and DEMO. To realize such a condition, 40 MeV deuteron beam with a current of 250 mA is injected into high speed liquid Li flow with a speed of 20 m/s. In target system, radioactive species such as Be, tritium and activated corrosion products are generated. In addition, back wall operates under severe conditions of neutron irradiation damage (about 50 dpa/y). In this paper, the thermal structural analysis and the accessibility evaluation of the IFMIF Li loop are summarized as JAEA activities on the IFMIF target system performed in FY2005.

IFMIF thermostructural analysis in the target back wall

Chida, Teruo; Ida, Mizuho; Nakamura, Hiroo; Sugimoto, Masayoshi; Simakov, S. P.*

no journal, , 

no abstracts in English