Upgrade of an integrated Langmuir probe system on the closed divertor target plates in the HL-2A tokamak

Abstract A newly designed divertor Langmuir probe diagnostic system has been installed in a rare closed divertor of the HL-2A tokamak and steadily operated for the study of divertor physics involved edge-localized mode (ELM) mitigation, detachment and redistribution of heat flux, etc. Two sets of probe arrays including 274 probe tips were placed at two ports (approximately 180° separated toroidally), and the spatial and temporal resolutions of this measurement system could reach 6 mm and 1 s, respectively. A novel design of the ceramic isolation ring can ensure reliable electrical insulation property between the graphite tip and the copper substrate plate where plasma impurities and the dust are deposited into the gaps for a long experimental time. Meanwhile, the condition monitoring and mode conversion between single and triple probe of the probe system could be conveniently implemented via a remote control station. The preliminary experimental result shows that the divertor Langmuir probe system is capable of measuring the high spatiotemporal parameters involved the plasma density, electron temperature, particle flux as well as heat flux during the ELMy H-mode discharges.

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A compact and portable PC-based Gundestrup–Langmuir probe diagnostic system

Review of Scientific Instruments ◽

10.1063/1.1834705 ◽

2005 ◽

Vol 76 (1) ◽

pp. 013505 ◽

Cited By ~ 1

Author(s):

P. Sicard ◽

C. Boucher ◽

A. Litnovsky ◽

J.-P. St-Germain

Keyword(s):

Langmuir Probe ◽

Diagnostic System

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Development of popup Langmuir probe system for the JET MkIIa divertor

Fusion Engineering and Design ◽

10.1016/s0920-3796(99)00063-0 ◽

1999 ◽

Vol 46 (1) ◽

pp. 27-35 ◽

Cited By ~ 4

Author(s):

S.J Davies ◽

X Tellier ◽

G.F Matthews ◽

C.H Wilson

Keyword(s):

Langmuir Probe ◽

Probe System

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Performance Evaluation of Minimum Quantity Lubrication With Exfoliated Graphite Nanoplatelets in Turning Titanium Alloy

Volume 4: Processes ◽

10.1115/msec2018-6599 ◽

2018 ◽

Author(s):

Dinh Nguyen ◽

Pil-Ho Lee ◽

Yang Guo ◽

Patrick Kwon ◽

Kyung-Hee Park

Keyword(s):

Minimum Quantity Lubrication ◽

Exfoliated Graphite ◽

Experimental Result ◽

Graphite Nanoplatelets ◽

Crater Wear ◽

Minimum Quantity ◽

Preliminary Experimental Result ◽

Tribological Surfaces ◽

Exfoliated Graphite Nanoplatelets ◽

Carbide Inserts

This paper evaluates the performances of dry, minimum quantity lubrication (MQL) and MQL with nanofluid in turning the most common titanium (Ti) alloy, Ti-6Al-4V, in a solution treated and aged (STA) microstructure. In particular, the nanofluid evaluated here is vegetable oil (rapeseed) mixed with small concentrations of exfoliated graphite nanoplatelets (xGnP). The focus of this paper is on turning process because it poses a challenging condition to apply oil droplets directly onto the tribological surfaces of a cutting tool due to the continuous engagement of tool and work material. A series of turning experiments was conducted with uncoated carbide inserts while measuring the cutting forces with the dynamometer under various conditions to determine its effectiveness and optimal MQL condition in turning. The worn inserts are retrieved to measure flank and crater wear using confocal microscopy. This preliminary experimental result shows that the use of MQL and nanofluid is effective in improving the machinability of Ti alloys in turning processes.

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A Langmuir probe system incorporating the Boyd–Twiddy method for EEDF measurement applied to an inductively coupled plasma source

Plasma Sources Science and Technology ◽

10.1088/0963-0252/18/1/014010 ◽

2008 ◽

Vol 18 (1) ◽

pp. 014010 ◽

Cited By ~ 7

Author(s):

B Crowley ◽

S Dietrich

Keyword(s):

Langmuir Probe ◽

Inductively Coupled Plasma ◽

Plasma Source ◽

Inductively Coupled ◽

Probe System

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The Multi-Needle Langmuir Probe System on Board NorSat-1

Space Science Reviews ◽

10.1007/s11214-018-0509-2 ◽

2018 ◽

Vol 214 (4) ◽

Cited By ~ 6

Author(s):

H. Hoang ◽

L. B. N. Clausen ◽

K. Røed ◽

T. A. Bekkeng ◽

E. Trondsen ◽

...

Keyword(s):

Langmuir Probe ◽

Probe System

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Experimental Investigation of Boiling Heat Transfer in a Liquid Chamber With Partially Soluble Nanofluids

10.1115/ipack2021-67330 ◽

2021 ◽

Author(s):

Noriyuki Unno ◽

Kazuhisa Yuki ◽

Risako Kibushi ◽

Rika Nogita ◽

Atsuyuki Mitani

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Boiling Heat Transfer ◽

Electronic Devices ◽

High Heat ◽

Experimental Result ◽

High Heat Flux ◽

Promising Technique ◽

Cooling Device ◽

Cooling Devices

Abstract Boiling heat transfer (BHT) is a promising technique to remove a high heat flux emitted from next-generation electronic devices. However, critical heat flux (CHF) is a big problem in BHT because it restricts the maximum performance of the cooling devices using BHT. Nanofluid has been widely used to improve the CHF. In this study, the authors investigated the BHT of a compact cooling device at low pressure using a special nanofluid: that is made with partially soluble particles in water. The experimental result found that the CHF with the special nanofluid is 170 W/cm2 and is higher than that with nanofluid made with an insoluble nanoparticle.

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Design and characterization of a copper microchannel heat sink for SiP cooling

Modern Physics Letters B ◽

10.1142/s0217984921400157 ◽

2021 ◽

pp. 2140015

Author(s):

Min Miao ◽

Hao Zhang ◽

Hejie Yu ◽

Lili Cao

Keyword(s):

Heat Flux ◽

Heat Sink ◽

Heat Dissipation ◽

Electrical Discharge Machining ◽

Copper Substrate ◽

Integrated System ◽

Peak Temperature ◽

Microchannel Heat Sink ◽

Set Up ◽

Electronic Hardware

With the increasing flourishing of miniaturized, multifunctional, and heterogeneously integrated system in package (SiP), heating problem is becoming more and more serious. In this paper, to meet the heat dissipation needs of the chips thus assembled and to achieve effective thermal management, linear, serpent and spiral shaped microchannel heat sinks were designed and fabricated into copper substrate by electrical discharge machining (EDM) and precision machining technology, acting both as the cooler and mounting base for passive and active SiP interposers. A test platform was set up to characterize the heat dissipation performance of the copper-based microchannel heat sink. The experimental and simulation results show that heat dissipation rate increases with the increasing heat flux density in the range 5–30 W/cm2 for the three microchannel designs, and the peak temperature can all be kept below 340 K (67[Formula: see text]C) even for the highest heat flux. The three designs are compared from the perspective of peak temperature, temperature distribution uniformity and pressure drop. In all, the solution proposed hereby provides a new and optimal option for in-situ cooling for densely integrated electronic hardware.

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