Measurement of the 2-D distribution of power loading on the TFTR bumper limiter during disruptions

Journal Article · Mon Oct 01 04:00:00 EDT 1990 · Review of Scientific Instruments; (USA)

DOI:https://doi.org/10.1063/1.1141743· OSTI ID:6350695

Janos, A C; Corneliussen, M; Fredrickson, E; McGuire, K M; Owens, K; Ulrickson, M ^[1]

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1. Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (USA)

Power loading on the first wall of a tokamak is an important issue in present research devices and in the design of future devices such as CIT and ITER. In particular, disruptions can deposit large amounts of power in localized areas which can then damage the wall or adversely affect operation. The plasma-facing wall in the Tokamak Fusion Test Reactor (TFTR) is covered in large part by a bumper limiter. This limiter extends the full 360{degree} toroidally inside the vacuum vessel on the small-major-radius side, and {plus minus}60{degree} poloidally with respect to the midplane. The TFTR tokamak has the unique feature that the bumper limiter is extensively instrumented with thermocouples. By carefully eliminating noise on the data from these sensors, we can now measure the heat deposition distribution for each discharge. We investigated disruptions due to operation at different operating limits such as (a) high density, (b) low {ital q}{sub {ital a}}, and (c) high beta poloidal ({beta}{sub {ital p}}). It was found that while there were often common hot spots, different types of disruptions caused different heating patterns and heat loads on the bumper limiter. We also studied the heat distribution created by pulsed discharge cleaning and disruptive discharge cleaning. While originally intended to study disruptions, this new analysis tool has proven valuable for investigating other plasma phenomena such as blooms and detached plasmas, determining the heating effectiveness of various conditioning techniques such as pulsed discharge cleaning and disruptive discharge cleaning, and verifying and checking the alignment of the bumper limiter.

• DOE Contract Number: AC02-76CH03073
• OSTI ID: 6350695
• Journal Information: Review of Scientific Instruments; (USA), Journal Name: Review of Scientific Instruments; (USA) Vol. 61:10; ISSN RSINA; ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700209* -- Fusion Power Plant Technology-- Component Development & Materials Testing
CLEANING
CONTAINMENT
CONTAINMENT SHELLS
ELECTRIC DISCHARGES
LIMITERS
PLASMA DIAGNOSTICS
POWER DENSITY
PULSES
TEMPERATURE DISTRIBUTION
TFTR TOKAMAK
THERMONUCLEAR REACTORS
TOKAMAK TYPE REACTORS
WALL LOADING