||Validation of Liquid Lithium Target Stability for an Intense Neutron Source
近藤, 浩夫 ,
Kanemura, Takuji ,
Furukawa, Tomohiro ,
Hirakawa, YasushiEakai, Eiichi
This paper reports on the validation results for the stability of a liquid lithium (Li) target being intended for use as an intense fusion neutron source such as the International Fusion Materials Irradiation Facility (IFMIF), the Advanced Fusion Neutron Source (A-FNS), and the DEMO Oriented Neutron Source (DONES). The variation in the thickness of a Li target must be suppressed to within ±1 mm inside a deuteron beam footprint to both maintain the integrity of the Li target and guarantee the desired level of the neutron flux. We achieve a stable Li target with an average thickness variation of just 0.17 mm inside the beam footprint under standard IFMIF operating conditions (target speed: 15 m/s, vacuum pressure: 10−3 Pa, and Li temperature: 250 °C). Moreover, the mean and maximum wave amplitudes under such conditions were found to be 0.26 mm and 1.46 mm, respectively, at the beam center; these are small enough to satisfy the operational requirements. Finally, it was determined that the stability of the Li target remained unchanged despite using it for a period of 1,561 h. This finding is regarded as a significant step toward the realization of the IFMIF and the potential use of relevant neutron sources such as A-FNS and DONES.