Design and measurement methods for a lithium vapor box similarity experiment

Journal Article · 10 August 2018 · Review of Scientific Instruments

DOI: https://doi.org/10.1063/1.5039406 · OSTI ID:1465999

Schwartz, J. A.  ^[1]; Emdee, E. D. ^[1]; Jaworski, M. A. ^[2]; Goldston, R. J. ^[1]

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1. Princeton Univ., Princeton, NJ (United States)
2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Here, the lithium vapor box divertor is a concept for handling the extreme divertor heat fluxes in magnetic fusion devices. In a baffled slot divertor, plasma interacts with a dense cloud of Li vapor which radiates and cools the plasma, leading to recombination and detachment. Before testing on a tokamak, the concept should be validated: we plan to study detachment and heat redistribution by a Li vapor cloud in laboratory experiments. Mass changes and temperatures are measured to validate a direct simulation Monte Carlo model of neutral Li. The initial experiment involves a 5 cm diameter steel box containing 10 g of Li held at 650 °C as vapor flows out a wide nozzle into a similarly sized box at a lower temperature. Diagnosis is made challenging by the required material compatibility with lithium vapor. Vapor pressure is a steep function of temperature, so to validate mass flow models to within 10%, absolute temperature to within 4.5 K is required. The apparatus is designed to be used with an analytical balance to determine mass transport. Details of the apparatus and methods of temperature and mass flow measurements are presented.

• Research Organization: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC02-09CH11466
• OSTI ID: 1465999
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 10 Vol. 89; ISSN 0034-6748
• Publisher: American Institute of Physics (AIP)Copyright Statement
• Country of Publication: United States
• Language: English