Comparison of pool boiling CHF of a polished copper block and carbon steel block on a declined slope

This paper presents the results of an experimental study of heat transfer in a pool boiling evaporator with porous insert. Different types of graphite foams were tested with the phase change coolant FC-72 in a designed thermosyphon. Comparisons between the graphite foams and a solid copper block show that the porous structure enhances pool boiling significantly. The boiling thermal resistance of the tested graphite foams was found to be about 2 times lower than that of the copper block. The bubble formation recorded by a high speed camera indicates that boiling from a graphite foam is more vigorous than from a copper block. The designed thermosyphon with graphite foam insert can remove heat fluxes of up to 112 W/cm2 with the maximum heater temperature maintained below 100°C.

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Pool Boiling Experiments on Multiwalled Carbon Nanotube (MWCNT) Forests

Journal of Heat Transfer ◽

10.1115/1.2349511 ◽

2006 ◽

Vol 128 (12) ◽

pp. 1335-1342 ◽

Cited By ~ 88

Author(s):

Hee Seok Ahn ◽

Nipun Sinha ◽

Mei Zhang ◽

Debjyoti Banerjee ◽

Shaoli Fang ◽

...

Keyword(s):

Heat Flux ◽

Silicon Wafer ◽

Pool Boiling ◽

Chemical Vapor ◽

Film Boiling ◽

Copper Block ◽

Multiwalled Carbon ◽

Boiling Regime ◽

Vertically Aligned ◽

Working Liquid

In this study, two silicon wafer substrates were coated with vertically aligned multiwalled carbon nanotubes (MWCNT) “forests” and were used for pool boiling studies. The MWCNT forests (9 and 25μm in height) were synthesized on the silicon wafer substrates using chemical vapor deposition (CVD) process. The substrates were clamped on a cylindrical copper block with embedded cartridge heaters. The heat flux was measured using sheathed K-type thermocouples, which were placed inside the cylindrical copper block. Pool boiling experiments using refrigerant PF-5060 as the working liquid were conducted to obtain the pool “boiling curve.” The experiments were conducted in nucleate and film boiling regimes to investigate the effect of MWCNT height on pool boiling performance. Reference (control) experiments were also performed with an atomically smooth bare silicon wafer (without MWCNT coating). The results show that the MWCNT forests enhanced critical heat flux (CHF) by 25-28% compared to control experiments. For the film boiling regime, Type-B MWCNT (25μm in height) yields 57% higher heat flux at Leidenfrost point (film boiling regime) compared to control experiments. However, for the Type-A MWCNT (9μm in height) the film boiling heat flux values are nearly identical to the values obtained for the control experiments performed on bare silicon.

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Oxidation effect on the pool boiling critical heat flux of the carbon steel substrates

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2015.10.047 ◽

2016 ◽

Vol 93 ◽

pp. 1008-1019 ◽

Cited By ~ 13

Author(s):

Hong Hyun Son ◽

Uiju Jeong ◽

Gwang Hyeok Seo ◽

Sung Joong Kim

Keyword(s):

Heat Flux ◽

Carbon Steel ◽

Critical Heat Flux ◽

Pool Boiling ◽

Steel Substrates ◽

Oxidation Effect

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Boiling Performance of Flourinert PF 5060 on Confined and Unconfined Wire Meshes Soldered to the Substrate

Heat Transfer, Part A ◽

10.1115/imece2005-82595 ◽

2005 ◽

Cited By ~ 2

Author(s):

David W. Gerlach ◽

Yogendra K. Joshi

Keyword(s):

Pool Boiling ◽

Copper Block ◽

Micron Diameter ◽

Wire Meshes

The boiling performance of the dielectric fluorocarbon liquid PF 5060 was measured on submerged 0.9 cm square tin-plated copper and bronze wire meshes soldered to a copper block. Three mesh sizes were tested: 8 wires/cm (20 wires/inch) with 406 micron diameter, 20 wires/cm (50 wires/inch) with 229 micron diameter, and 59 wires/cm (150 × 150 wires/inch) with 66 micron diameter. The curves were measured with top of the mesh open in a pool boiling arrangement and with the mesh covered with a plate so that bubbles must exit sideways.

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Effects of carbon steel surface oxidation on critical heat flux in downward-face pool boiling

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2019.03.020 ◽

2019 ◽

Vol 136 ◽

pp. 470-485 ◽

Cited By ~ 6

Author(s):

Kai Wang ◽

Nejdet Erkan ◽

Haiguang Gong ◽

Koji Okamoto

Keyword(s):

Heat Flux ◽

Carbon Steel ◽

Critical Heat Flux ◽

Steel Surface ◽

Pool Boiling ◽

Surface Oxidation ◽

Carbon Steel Surface

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Pyrolytic carbon filaments and associated catalytic particles formed in steel tubes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100113196 ◽

1984 ◽

Vol 42 ◽

pp. 662-663

Author(s):

Y. L. Chen ◽

J. R. Bradley

Keyword(s):

Stainless Steel ◽

Carbon Steel ◽

Catalyst Particle ◽

Pyrolytic Carbon ◽

Plain Carbon Steel ◽

304 Stainless Steel ◽

Hydrocarbon Gases ◽

Steel Tubes ◽

Filamentous Carbon ◽

Carbon Filaments

Considerable effort has been directed toward an improved understanding of the production of the strong and stiff ∼ 1-20 μm diameter pyrolytic carbon fibers of the type reported by Koyama and, more recently, by Tibbetts. These macroscopic fibers are produced when pyrolytic carbon filaments (∼ 0.1 μm or less in diameter) are thickened by deposition of carbon during thermal decomposition of hydrocarbon gases. Each such precursor filament normally lengthens in association with an attached catalyst particle. The subject of filamentous carbon formation and much of the work on characterization of the catalyst particles have been reviewed thoroughly by Baker and Harris. However, identification of the catalyst particles remains a problem of continuing interest. The purpose of this work was to characterize the microstructure of the pyrolytic carbon filaments and the catalyst particles formed inside stainless steel and plain carbon steel tubes. For the present study, natural gas (∼; 97 % methane) was passed through type 304 stainless steel and SAE 1020 plain carbon steel tubes at 1240°K.

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Internal friction in a martensitic high-carbon steel

Philosophical Magazine A ◽

10.1080/01418610110049716 ◽

2001 ◽

Vol 81 (12) ◽

pp. 2797-2808

Author(s):

Rustem Bagramov, Daniele Mari, Willy Benoi

Keyword(s):

Carbon Steel ◽

Internal Friction ◽

High Carbon Steel ◽

High Carbon

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Development of trimming technology for hot rolled ultra-low carbon steel

Revue de Métallurgie ◽

10.1051/metal/199390070917 ◽

1993 ◽

Vol 90 (7-8) ◽

pp. 917-922

Author(s):

Y. Matsuda ◽

M. Nishino ◽

J. Ikeda

Keyword(s):

Carbon Steel ◽

Low Carbon Steel ◽

Low Carbon ◽

Ultra Low Carbon Steel ◽

Hot Rolled

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INFLUENCE THE QUENCHING AND TEMPERING ON THE MICROSTRUCTURE, MECHANICAL PROPERTIES AND SURFACE ROUGHNESS, OF MEDIUM CARBON STEEL

THE IRAQI JOURNAL FOR MECHANICAL AND MATERIALS ENGINEERING ◽

10.32852/iqjfmme.vol18.iss1.78 ◽

2018 ◽

Vol 18 (1) ◽

pp. 125-135

Author(s):

Sattar H A Alfatlawi

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Surface Roughness ◽

Carbon Steel ◽

Cold Water ◽

Medium Carbon Steel ◽

Medium Carbon ◽

Heating And Cooling ◽

Treatment Processes ◽

Quenching And Tempering

One of ways to improve properties of materials without changing the product shape toobtain the desired engineering applications is heating and cooling under effect of controlledsequence of heat treatment. The main aim of this study was to investigate the effect ofheating and cooling on the surface roughness, microstructure and some selected propertiessuch as the hardness and impact strength of Medium Carbon Steel which treated at differenttypes of heat treatment processes. Heat treatment achieved in this work was respectively,heating, quenching and tempering. The specimens were heated to 850°C and left for 45minutes inside the furnace as a holding time at that temperature, then quenching process wasperformed in four types of quenching media (still air, cold water (2°C), oil and polymersolution), respectively. Thereafter, the samples were tempered at 200°C, 400°C, and 600°Cwith one hour as a soaking time for each temperature, then were all cooled by still air. Whenthe heat treatment process was completed, the surface roughness, hardness, impact strengthand microstructure tests were performed. The results showed a change and clearimprovement of surface roughness, mechanical properties and microstructure afterquenching was achieved, as well as the change that took place due to the increasingtoughness and ductility by reducing of brittleness of samples.

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