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arXiv · 2306.02653

thermal and stress_strain analysis of the tested iter-like w langmuir probes in east

Chunyu He·Dahuan Zhu
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Abstract

ITER-like tungsten Langmuir probes (W DLPs) have been installed and tested at the lower divertor horizontal target composed of flat-type components in EAST. Due to the non-active cooling, transient thermal and stress\strain analyses considering actual thermal loading and cooling conditions were thus conducted to evaluate the thermal performance and mechanical quality of W DLPs subjected to the long pulse & high plasma flux of EAST. The thermal analysis reveals that the inevitable leading edge induced thermal loading at surrounding area of W DLPs is not ignorable. The thermal performance of W DLPs are largely related to the plasma scenario (Qp: parallel heat flux along magnetic field line, {\alpha}: incline angle of magnetic field line). Under current plasma parameters, melting of W was not occurred in general, but recrystallization as well as the induced cracks may be still possible. And, the interval period (~1000 s) between neighboring shots is sufficient for nature cooling of W DLPs. The stress analysis also tells that the ceramic LLL may be general a crucial weak point of W DLPs, which is expected to not only limit the thermal affordability of long pulse but also cause possible crack problems. Such calculation results can provide important reference for current plasma operation and future improvement of the W DLPs.

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Chunyu He, Dahuan Zhu. 2023-06-05. thermal and stress_strain analysis of the tested iter-like w langmuir probes in east. https://arxiv.org/abs/2306.02653

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