Critical heat flux enhancement in pool boiling using alumina nanofluids

Hegde, Ramakrishna N.; Rao, Srikanth S; Reddy, M. R. P.

doi:10.1002/htj.20301

Cited by 12 publications

(6 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…11. The variation in the heat flux values were similar to the trend observed by Bang et al [4], Hegde et al [15] and Kim [18]. Wherein heat flux increased with concentration, a reverse trend was observed in the studies of Kim and Bang [17].…”

Section: Discussion On Changed Boiling Performancesupporting

confidence: 90%

“…Therefore, the reasons for this conflicting performance may be related to differences in the surface characteristics between the boiling surface and nano-fluids. Hegde et al [15] found that the roughness of the heater surface considerably decreased changes in the boiling characteristics. In order to confirm the nanoparticle coating over the heater surface, SEM images of the bare surface of the heater were taken before starting the experiment and the surface roughness (Ra value) was measured using the Mitutoyo Surf test.…”

Section: Discussion On Changed Boiling Performancementioning

confidence: 98%

See 1 more Smart Citation

Experimental study on CuO nanoparticles in distilled water and its effect on heat transfer on a vertical surface

2011

Self Cite

View full text Add to dashboard Cite

The pool boiling characteristics of dilute dispersions of CuO nanoparticles in water were studied at atmospheric pressure on a vertical heating surface. Experimental investigation of different weight concentrations of nanoparticles revealed significant enhancement in heat flux and deterioration in pool boiling. Out of many reasons, nanoparticles coating the heater surface was believed to be the reason behind this. Subsequent inspection of the heater surface showed nanoparticles coating the surface, forming a porous layer. To substantiate the nanoparticle deposition and its effect on heat flux, an investigation was performed by measuring the surface roughness of the heater surface before and after the experiment. While SEM images of the heater surface revealed nanoparticle deposition, measurement of surface roughness of the heater surface confirmed it. Formation of the porous layer on the heater surface as revealed by SEM images provided an excellent location for nucleation sites enhancing heat transfer. However, deterioration in nucleate boiling at different weight concentrations indicated some phenomenon is working behind this.

show abstract

Section: Discussion On Changed Boiling Performancesupporting

confidence: 90%

Section: Discussion On Changed Boiling Performancementioning

confidence: 98%

Experimental study on CuO nanoparticles in distilled water and its effect on heat transfer on a vertical surface

2011

Self Cite

View full text Add to dashboard Cite

show abstract

“…Many other studies consider the primary reason for CHF enhancement is due to the surface coating effect [99,100,106,[108][109][110][111]. For example, Bang and Chang [99] conducted an experimental study on boiling heat transfer characteristics of nanofluids with nanoparticles suspended in water using different concentrations of alumina nanoparticles.…”

Section: Nucleate Pool Boiling Heat Transfer and Chf Mechanisms Of Namentioning

confidence: 97%

A critical synthesis of thermophysical characteristics of nanofluids

Khanafer¹,

Vafai²

2011

International Journal of Heat and Mass Transfer

958

219

View full text Add to dashboard Cite

“…Therefore, the reasons for this conflicting performance may be related to differences in the surface characteristics between the boiling surface and nanofluids. Hegde et al [22] found that the surface roughness of the heater surface decreased, which changed the boiling characteristics. Modification of the heater surface due to change in surface roughness (Ra value) was measured using the Mitutoyo Surftest-SJ301, a surface profilometer.…”

Section: Effect Of Pressure On Boiling Heat Transfermentioning

confidence: 98%

Experimental Investigations of Pool Boiling Heat Transfer Characteristics on a Vertical Surface Using CuO Nanoparticles in Distilled Water

Hegde¹,

Rao²,

Reddy

2014

Heat Transfer Engineering

View full text Add to dashboard Cite

Experiments were conducted on pool boiling heat transfer using dilute dispersions of CuO nanoparticles in distilled water at and above atmospheric pressure. Pool boiling characteristics of CuO nanofluid were studied at different pressures and concentrations. Characterization of the heating surface was done both qualitatively and quantitatively by taking the scanning electron microscopy (SEM) images and by subsequent measurement of surface roughness of the heater. SEM images of the heater surface showed nanoparticle deposition on the heater surface, suggesting surface modification. Thorough visualization showed microcavities on the heater surface, which provide an excellent location for nucleation sites enhancing heat transfer. However, these microcavities, once filled up with the suspended nanoparticles, reduced active nucleation sites, deteriorating the boiling heat transfer coefficient. Based on the experimental investigations it was concluded that there is an optimum thickness of nanoparticles coating at which heat flux is maximum and beyond this coating boiling heat transfer coefficient decreases. At higher pressures, boiling heat transfer coefficient and specific excess temperature remained nearly the same. This showed that pressure has negligible or no role to play in boiling heat transfer using nanofluids.

show abstract

Critical heat flux enhancement in pool boiling using alumina nanofluids

Cited by 12 publications

References 5 publications

Experimental study on CuO nanoparticles in distilled water and its effect on heat transfer on a vertical surface

Experimental study on CuO nanoparticles in distilled water and its effect on heat transfer on a vertical surface

A critical synthesis of thermophysical characteristics of nanofluids

Experimental Investigations of Pool Boiling Heat Transfer Characteristics on a Vertical Surface Using CuO Nanoparticles in Distilled Water

Contact Info

Product

Resources

About