Measured Variations in Local Surface Temperatures in Pool Boiling of Water

Hsu, Shu-Han; Schmidt, F. W.

doi:10.1115/1.3682252

Cited by 44 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Similar conclusions were reached by other researchers who used emery paper [16] and electrical discharge machining (EDM) [17] as surface roughening methods. A wide variety of fluids have been investigated for surfaces with various degrees of roughness, all showing that the cavities generated during roughening processes serve as nucleation sites [18,19]. Since the shape of cavities on roughened surfaces is the primary determinant of their role as nucleation sites, reentrant cavities were proposed and shown to serve as more stable nucleation sites due to the reversed curvature of the liquid-vapor interface within the cavity [20].…”

Section: Introductionmentioning

confidence: 99%

A free-particles-based technique for boiling heat transfer enhancement in a wetting liquid

Kim

Weibel

Garimella

2014

International Journal of Heat and Mass Transfer

View full text Add to dashboard Cite

An easy-to-implement technique for pool boiling heat transfer enhancement is proposed and evaluated through an experimental investigation. This free-particle technique brings about nucleate boiling at a low degree of superheat by means of metal particles that are not fixed to the heated surface, but rather are free to move with respect to the surface. The effects of copper particles with sizes ranging from tens of nanometers to 9 mm on nucleate boiling heat transfer and critical heat flux (CHF) of the wetting dielectric fluid FC-72 are investigated. Visualizations of the bubble nucleation characteristics due to the free particles are presented. Experimental results show that the introduction of microscale free particles onto a superheated surface effectively facilitates bubble nucleation and thus increases the nucleate boiling heat transfer coefficients. Millimeter-sized as well as nanoscale free particles do not have a strong effect on the boiling heat transfer performance of this wetting fluid. Introduction of a large quantity of microscale free particles reduces CHF by increasing the resistance to liquid replenishment and vapor departure; however, by properly selecting particle size and quantity, an improvement in both nucleate boiling heat transfer and CHF is observed. For the case where 0.2 g of 10 μm-diameter free particles are placed on a polished copper surface, corresponding to a particle layer thickness of approximately 67 μm, the average nucleate boiling heat transfer coefficient is enhanced by 76.3% over the heat flux range of 10 to 159 kW/m 2 , while CHF is increased by 10%.

show abstract

Section: Introductionmentioning

confidence: 99%

A free-particles-based technique for boiling heat transfer enhancement in a wetting liquid

Kim

Weibel

Garimella

2014

International Journal of Heat and Mass Transfer

View full text Add to dashboard Cite

show abstract

“…While surface roughening is well known to provide improvement in boiling heat transfer [2][3][4][5], reliance on this enhancement approach has generally been commercially intractable due to aging effects and difficulty in achieving repeatable and predictable performance. Jakob [6], Corty and Foust [7], and…”

Section: Introductionmentioning

confidence: 99%

Investigation of boiling heat transfer in water using a free-particles-based enhancement technique

Kim

Garimella

2014

International Journal of Heat and Mass Transfer

View full text Add to dashboard Cite

Enhancement of pool boiling heat transfer in water by means of the introduction of free particles on the heated surface is investigated. The layer of loose particles on the heated surface is free to move and deform under the action of bulk liquid convection and vapor nucleation. High-speed visualizations show that bubble nucleation preferentially occurs at the narrow corner cavities formed between the free particles and the heated surface. The effects of the number and size of the free particles are experimentally explored using copper particles over a wide size range from tens of nanometers to 13 mm.Experimental results show that a mixture of free particle diameters of 3 mm and 6 mm provides the greatest improvement in boiling heat transfer, resulting in an average increase in heat transfer coefficient of 115% relative to a baseline polished surface without particles. A numerical heat transfer simulation and an analytical force balance model are developed to predict nucleation incipience and explain the parametric trends in boiling performance observed in the presence of the free particles.

show abstract

“…Average surface roughness of the three samples would be different, although the surface finishing process was the same. Therefore, a profilometer should be used to measure Ra of the surfaces as suggested by [8,[11][12][13][14]. Figure 2 shows the results of the profilometer.…”

Section: Characteristics Of the Heating Surfacementioning

confidence: 99%

Concerning The Effect of Surface Material on Nucleate Boiling Heat Transfer of R-113

Hosseini¹,

Amir²,

Mahdi³

2011

JECTC

View full text Add to dashboard Cite

This paper presents results of an experimental investigation carried out to determine the effects of surface material on nucleate pool boiling heat transfer of refrigerant R113. Experiments were performed on horizontal circular plates of brass, copper and aluminum. The heat transfer coefficient was evaluated by measuring wall superheat and effective heat flux removed by boiling. The experiments were carried out in the heat flux range of 8 to 200 kW/m 2. The obtained results have shown significant effect of surface material, with copper providing the highest heat transfer coefficient among the samples, and aluminum the least. There was negligible difference at low heat fluxes, but copper showed 23% better performance at high heat fluxes than aluminum and 18% better than brass.

show abstract

Measured Variations in Local Surface Temperatures in Pool Boiling of Water

Cited by 44 publications

References 0 publications

A free-particles-based technique for boiling heat transfer enhancement in a wetting liquid

A free-particles-based technique for boiling heat transfer enhancement in a wetting liquid

Investigation of boiling heat transfer in water using a free-particles-based enhancement technique

Concerning The Effect of Surface Material on Nucleate Boiling Heat Transfer of R-113

Contact Info

Product

Resources

About