Table 1.

Main recent experimental works on boiling-induced nanoparticle deposition.

Reference	Authors/Year	Nanoparticles Material	Substrate Material	Effects on Heat Transfer	Other Effects
[19]	Raveshi et al./2013	Aluminum oxide	Copper	An HTC enhancement of up to 64% for the 0.75% vol. nanofluid was verified. Except for the increment of the base fluid properties, the heating surface alteration was the main factor influencing the HTC. Because the surface particle interaction parameter was more than the unity, only the increment of HTC was observed. At low concentration, the deposited layer was very thin, which altered the surface by multiplying the nucleate site and creating active cavities, and finally leading to enhancement of the heat transfer.	The thicker layer, which was recorded at the end of the boiling duration, was caused by the higher concentration of the nanoparticles.
[5]	Sarafraz and Hormozi/2014	Aluminum oxide	Stainless-steel	With increasing the concentration of nanofluids, due to the deposition of nanoparticles on the surface and equal size of nanoparticles and roughness of the heating surface, the average roughness of the surface decreased and, subsequently, the number of nucleation sites reduced which led to an HTC decrease.	An asymptotic behavior was reported for the particulate fouling at the heat transfer area, whereas a rectilinear behavior was found for the free convection region. The thickness and rate of fouling depended on the boiling duration and the fouling resistance because nucleate boiling was higher than those measured in the convection area.
[20]	Tang et al./2014	Aluminum oxide		The aluminum oxide nanoparticles enhanced the heat transfer at concentrations of 0.001 vol. %, 0.01 vol. %, and 0.1 vol. % with the SDBS surfactant. The aluminum oxide nanoparticles deteriorate the heat transfer at 0.1 vol. % without SDBS due to the larger number of deposited nanoparticles. The SDBS deteriorated the heat transfer, and the deterioration was more than the enhancement by the nanoparticles at 0.001 vol. %.When the fractions were between 0.01 vol. % and 0.1 vol. %, the addition of the SDBS improved the heat transfer by the nanoparticles because the SDBS reduced the deposition of nanoparticles.	The impact of the change in the surface angle by the surface deposition of the nanoparticles can be negligible for R141b.
[21]	Manetti et al./2017	Aluminum oxide	Copper	A decrease in the wall superheating up to 32% and 12% for a smooth and rough surfaces, respectively, was verified for the same heat flux in comparison with that of DI water. For low concentration nanofluids subjected to moderate heat flux, appreciable enhancement of the HTC was observed for the smooth and rough surfaces as compared with the DI water. It is argued that this phenomenon is related to the increase in the radius of the cavities due to changes in the morphology of the surface. For the rough surface, the HTC decreased appreciably with increasing heat flux due to the intensification of the nanoparticle deposition rate, and higher thermal resistance by the filling of the cavities of the heating surface with the nanoparticles. The surface modification due to the nanoparticle deposition increased the HTC only for low nanoparticle concentrations and when the particle interaction parameter (SIP) was greater than unity.	A higher nanoparticle deposition rate occurred for heat fluxes greater than 400 kW/m2.
[22]	Nunes et al./2020	Aluminum oxide	Copper	The coating layer formed on the heating surface increased the surface wettability; moreover, it provided a barrier to the heat transfer by increasing the thermal resistance on the heating surface, degrading the HTC for unconfined and confined boiling. For the latter, the wettability enhancement promoted a delay in the dryout incipience phenomenon.	The coating process delayed the dryout occurrence under confined conditions due to the influence of the nanostructures on the surface–fluid interaction mechanisms, e.g., the surface wettability, which is a pronounced effect for non-wetting fluids, such as the DI water.
[23]	Xing et al./2016	Carbon	Copper	The multi-walled nanotubes (MWNTs) with CTAB nanofluid presents poor HTC, which decrease with increasing concentration for the deposition of nanoparticles. The deposition of nanoparticles onto the heating surface was not verified using covalent functionalization MWNTs nanofluids. Thus, the covalent functionalization MWNTs nanofluids show a higher HTC than the base fluid, and they increased as the MWNTs concentration increased. The maximum HTC enhancements are 34.2% and 53.4% for MWNTs-COOH and MWNTs-OH nanofluids, respectively.	…..
[24]	Li et al./2020	Copper oxide	Copper	The HTC was improved due to the partial fouling of the nanoparticles which increased the number of nucleation sites on the surface. After 1000 min of operation, the fouling layer changed the surface by decreasing the number of nucleation sites, inducing a thermal resistance to the surface and decreasing the bubble departure time.	…..
[25]	Cao et al./2019	Copper–zinc	Copper	The superheat value on the fully deposited surfaces was around 20 K lower than that on the smooth surface and the fully deposited surface had the highest HTC, around 100% enhancement than the smooth surface. The CHF was not enhanced on the fully deposited surface, but increased by 33% on the channel-pattern-deposited surfaces.	The experimental CHF on the channel pattern deposited surfaces agree well with the predicted model derived from hydrodynamic instability
[26]	Kiyomura et al./2017	Iron oxide	Copper	The coated layer formed on the rough surfaces provided a barrier to the heat transfer and reduced the bubble nucleation, which led to the reduction in the number of microcavities and an increase in the thermal resistance, therefore degrading the HTC. For smooth surfaces, the deposition of nanoparticles tends to increase the nucleation site’s density, increasing the boiling heat transfer. An increment in the HTC occurred only for low nanofluid concentrations, for which the thermal conductivity of the nanofluids was dominant as compared with the thermal resistance of the nanolayer formed on the heating surface.	The C coefficient that correlates to the HTC and the heat flux was used. Different Csf (surface–fluid parameter) and Cs (heating surface parameter) behaviors were found for the surfaces covered with nanoparticles. The Csf and Cs are influenced by the additional thermal resistance resulting from the nanoparticle deposition. The Cs underestimated the effects of wettability and surface roughness for the surfaces covered with nanoparticles
[27]	Stutz et al./2011	Maghemite	Platinum	The coating made of nanoparticles reduced the HTC by introducing a thermal resistance that increased with layer thickness. The CHF enhancement depended on the covering rate of the heating surface by the nanoparticles, and evolved with boiling time. It reached a maximum when the heater was entirely covered with nanoparticles and then decreased slowly when the thickness of the coating increased. The observed increase in the CHF was due to the increase in the heat transfer area when the nanoporous layer was formed.	The effective thermal resistance of the layer appears to decrease substantially during boiling and seems to be coupled to the bubble dynamics. This may indicate that vapor generation occurs inside the layer, which reduces its effective thickness.
[28]	Souza et al./2014	Maghemite	Copper	It was observed that the enhancement of the HTC is higher when the SIP was greater than unity. The HTC for the nanostructured surface with the deposition of nanoparticles of 10 nm diameter, corresponding to SIP = 16, was 55% higher than that for the bare surface. For the nanostructured surface with the deposition of nanoparticles having 80 nm of diameter, corresponding to a SIP equal to 2, the HTC decreased 29%.The HTC increased when the gap decreased, mainly for lower heat fluxes. For a gap length equal to 0.1 mm, a 145% HTC increase at heat fluxes lower than 45 kW/m2 with the deposition of 10 nm sized nanoparticles was reported.	….
[29]	Heitich et al./2014	Maghemite	Copper–nickel alloy	Nanostructured surfaces showed higher wettability as a consequence of the greater number of surface defects created by the nanoparticles. Surface defects affect the contact angle and may influence the heat transfer and CHF. The nanostructures have a greater number of these defects due to the small nanoparticle size. The nanostructures led to an increase in the CHF, especially with the maghemite deposition for which the value was around 139% higher than that of the smooth substrate. The CHF increased as the wettability increased. An increase in the CHF was observed as the contact angle decreased. The rough substrate samples showed an enhancement in the HTC of around 19%, while other samples showed an increase in the HTC values for high heat fluxes	The maghemite nanostructured surfaces showed greater porosity and roughness. These samples have a greater nanoparticle layer thickness and, consequently, a higher wettability compared with the molybdenum samples. The rough substrate showed a hydrophobic behavior, while the other samples with nanoparticle deposition showed a hydrophilic behavior. The small particle sizes in the nanostructures greatly promoted the wettability alteration.
[30]	Rostamian and Etesami/2018	Silicon oxide	Copper	Whatever the time of boiling on the heating surface increases, the differences between the boiling curves of nanofluid and deionized water becomes more due to the deposition of nanoparticles. In high concentrations of nanofluid, further deposition of nanoparticles on the surface causes a thickening of the layer made of nanoparticles. This thick layer enhances thermal resistance, so the HTC reduces. However, in low concentrations the surface roughness is less than that in high concentrations and during the nanofluid boiling on the surface, nucleation sites with sedimentation of nanoparticles became smaller in size and the number of nucleation sites increased; therefore, the HTC increased. The main cause for the CHF enhancement in nanofluid was the nanoparticle deposition which increased the surface wettability and CHF was delayed to a higher surface superheat value.	Whenever the concentration and the time of boiling increases, the surface roughness increases, too. Moreover, the increase in surface roughness happens more quickly for higher concentrations (0.01 vol. %).
[31]	Akbari et al./2017	Silver	Copper	The deposition of nanoparticles was efficient in re-entrant inclined coated surfaces: up to 120% CHF increase compared with the smooth surface and up to 30% as compared with the uncoated inclined surface.	The bubbles generated on the coated re-entrant surface were larger in size.
[32]	Kumar et al./2017	Titanium oxide	Nickel–chromium	The CHF was augmented up to a certain value of nanoparticle deposition, beyond which the rate of deposition was intangible. Approximately 80%, 88%, and 93% enhancements in the CHF were found for deposition up to 4 min, 8 min, and 16 min, respectively.	The larger the deposition or boiling time, the lower the contact angle leading to a higher CHF. The rate of deposition of nanoparticles was higher for boiling times up to 8 min and was comparatively lower beyond 8 min and above.
[33]	Hadzic et al./2022	Titanium oxide	Copper	At a low nanoparticle concentration, the influence of nanofluid on boiling performance was minimal, with the HTC and CHF values comparable with those obtained using pure water on both the untreated and laser-textured surfaces. The boiling of a nanofluid with a high nanoparticle concentration resulted in a significant deposition of nanoparticles onto the boiling surface and CHF enhancement up to 2021 kW m−2, representing double the value obtained on the untreated reference surface using water. However, very high surface superheat values (up to 100 K) were recorded, suggesting poor practical applicability. The decrease in heat transfer performance due to the boiling of nanofluids on laser textured surfaces can be explained through the deposition of nanoparticles into the laser-induced grooves and microcavities present on the surface, which decreased the number of active nucleation sites.	Thicker nanoparticle deposits resulted in added thermal resistance. While the surface porosity granted a delay in the CHF incipience due to the enhanced liquid replenishment, the surface superheat value was increased.
[34]	Kamel and Lezsovits./2020	Tungsten oxide	Copper	The higher HTC enhancement ratio was 6.7% for a concentration of 0.01% vol. compared with deionized water. The HTC for nanofluids was degraded compared with the deionized water, and the maximum reduction ratio was about 15% for a concentration of 0.05% vol. relative to the baseline case. The reduction in the HTC was attributed to the deposition of tungsten oxide nanoflakes on the heating surface, which led to a decrease in the nucleation site’s density.	…..
[35]	Gajghate et al./2021	Zirconium oxide	Copper	The zirconia nanoparticle coating incremented the heat transfer and HTC. The peak enhancement in the HTC was of 31.52% obtained for 200 nm zirconium-oxide-coating thickness. The HTC increased with increasing coating thickness up to 200 nm, but a further increment in the thickness resulted in the reduction in HTC due to the rise in thermal resistance.	The increase in zirconium oxide nanoparticle concentration from 0.1 to 0.5 vol. % showed an increase in the coating thickness as well as surface roughness. The zirconium oxide layer gave hydrophilicity to the bare copper surface.
[36]	Minakov et al./2017	Silicon, aluminum, iron oxides, and diamond	Nickel–chromium	Even at very small concentrations of nanoparticles, the CHF increased by more than 50% and continued growing with a further increase in the nanoparticle concentration. At high concentrations of nanoparticles, the growth rate of CHF slowed down and reached a constant value. Such behavior can be explained by the stabilization of the deposit size on the heating surface. With increasing boiling time, the CHF increased rapidly and reached a steady-state level. The correlation between CHF and the concentration, particle size and material, and boiling time confirmed the key role of the nanoparticle deposition.	At the same nanoparticle concentration, the desired height of the layer deposited on a smaller heating surface was formed much faster than that deposited on a larger heating surface.
[37]	Sulaiman et al./2016	Titanium oxide, aluminum oxide and silicon oxide	Copper	The aluminum oxide nanofluids enhanced, whereas the silicon oxide nanofluids deteriorated, the heat transfer. The effect of the titanium oxide nanofluid on the heat transfer depended on the nanoparticle concentration. The maximum CHF was found for the most concentrated aluminum oxide nanofluid. Although significant detachment of the nanoparticle layer was found after the CHF measurement for the silicon oxide nanofluids, the value of CHF was not significantly different from those for the titanium oxide and aluminum oxide nanofluids.	Abnormal increase in the wall superheat value was observed for the titanium oxide and silicon oxide nanofluids when the heat flux was sufficiently high. It was considered that this phenomenon was related to the partial detachment of the nanoparticle layer formed on the heated surface since the defects of the nanoparticle layer were always detected when such a temperature rise took place.