nanofluid

Thermal conductivity, viscosity, density, specific heat, and surface tension are significant thermophysical properties of nanofluids. Parameters such as nanoparticle type, size, shape, volume concentration, fluid temperature, and nanofluid preparation method affect thermophysical properties.{{Citation |last=Mahbubul |first=I. M. |title=4 - Thermophysical Properties of Nanofluids |date=2019-01-01 |work=Preparation, Characterization, Properties and Application of Nanofluid |pages=113–196 |editor-last=Mahbubul |editor-first=I. M. |url=https://www.sciencedirect.com/science/article/pii/B9780128132456000046 |access-date=2022-09-18 |series=Micro and Nano Technologies |publisher=William Andrew Publishing |language=en |isbn=978-0-12-813245-6}}

• Viscosity{{Cite journal |last1=Mahbubul |first1=I. M. |last2=Saidur |first2=R. |last3=Amalina |first3=M. A. |date=2012-01-31 |title=Latest developments on the viscosity of nanofluids |url=https://www.sciencedirect.com/science/article/pii/S0017931011005904 |journal=International Journal of Heat and Mass Transfer |language=en |volume=55 |issue=4 |pages=874–885 |doi=10.1016/j.ijheatmasstransfer.2011.10.021 |bibcode=2012IJHMT..55..874M |issn=0017-9310}}
• Density
• Thermal conductivity{{Cite web |title=Thermal Conductivity of Nanofluids |url=https://encyclopedia.pub/entry/9666 |access-date=2022-09-18 |website=encyclopedia.pub |language=en}}

Nanofluids are produced by several techniques:

• Direct Evaporation (1 step)
• Gas condensation/dispersion (2 step)
• Chemical vapour condensation (1 step)
• Chemical precipitation (1 step)
• Bio-based (2 step)

Base liquids include water, ethylene glycol, and oils have been used. Although stabilization can be a challenge, on-going research indicates that it is possible. Nano-materials used so far in nanofluid synthesis include metallic particles, oxide particles, carbon nanotubes, graphene nano-flakes and ceramic particles.{{cite journal|title= Heat Transfer in Nanofluids—A Review| doi=10.1080/01457630600904593 | bibcode=2006HTrEn..27....3D | volume=27|issue= 10|journal=Heat Transfer Engineering|pages=3–19 | last1 = Kumar Das | first1 = Sarit|date= December 2006| s2cid=121751385 | doi-access=free}}{{cite journal|title=A review on preparation methods and challenges of nanofluids|doi=10.1016/j.icheatmasstransfer.2014.03.002 | volume=54|journal=International Communications in Heat and Mass Transfer|pages=115–125 | last1 = Nor Azwadi | first1 = Che Sidik|year=2014 |bibcode=2014ICHMT..54..115S }}

A biologically-based, environmentally friendly approach for the covalent functionalization of multi-walled carbon nanotubes (MWCNTs) using clove buds was developed.{{cite journal |last1=Sadri |first1=R |title=A bio-based, facile approach for the preparation of covalently functionalized carbon nanotubes aqueous suspensions and their potential as heat transfer fluids |journal=Journal of Colloid and Interface Science |date=15 October 2017 |volume=504 |pages=115–123 |doi=10.1016/j.jcis.2017.03.051 |pmid=28531649 |bibcode=2017JCIS..504..115S }}{{cite journal |last1=Hosseini |first1=M |title=Experimental Study on Heat Transfer and Thermo-Physical Properties of Covalently Functionalized Carbon Nanotubes Nanofluids in an Annular Heat Exchanger: A Green and Novel Synthesis |journal=Energy & Fuels |date=February 22, 2017 |volume=31 |issue=5 |pages=5635–5644 |doi=10.1021/acs.energyfuels.6b02928 |s2cid=99426800 }} No toxic/hazardous acids are typically used in common carbon nanomaterial functionalization procedures, as employed in this synthesis. The MWCNTs are functionalized in one pot using a free radical grafting reaction. The clove-functionalized MWCNTs are then dispersed in distilled water (DI water), producing a highly stable MWCNT aqueous suspension (MWCNTs Nanofluid).

Nanofluids are primarily used for their enhanced thermal properties as coolants in heat transfer equipment such as heat exchangers, electronic cooling system(such as flat plate) and radiators.{{cite web|url=http://www.hindawi.com/journals/ame/2010/519659/|title=Advances in Mechanical Engineering|work=hindawi.com|access-date=8 June 2015}} Heat transfer over flat plate has been analyzed by many researchers.{{cite web|url=http://nanofluid.ir |title=Dr. AMINREZA NOGHREHABADI|archive-url=https://web.archive.org/web/20131111205120/http://nanofluid.ir/ |archive-date=2013-11-11 }} However, they are also useful for their controlled optical properties.{{Cite journal|last1 = Phelan|first1 = Patrick|last2 = Otanicar|first2 = Todd|last3 = Taylor|first3 = Robert|last4 = Tyagi|first4 = Himanshu|date = 2013-05-17|title = Trends and Opportunities in Direct-Absorption Solar Thermal Collectors|journal = Journal of Thermal Science and Engineering Applications|volume = 5|issue = 2|pages = 021003|doi = 10.1115/1.4023930|issn = 1948-5085}}{{Cite journal|last1 = Hewakuruppu|first1 = Yasitha L.|last2 = Dombrovsky|first2 = Leonid A.|last3 = Chen|first3 = Chuyang|last4 = Timchenko|first4 = Victoria|last5 = Jiang|first5 = Xuchuan|last6 = Baek|first6 = Sung|last7 = Taylor|first7 = Robert A.|date = 2013-08-20|title = Plasmonic "pump–probe" method to study semi-transparent nanofluids|journal = Applied Optics|volume = 52|issue = 24|doi = 10.1364/ao.52.006041|pmid=24085009|pages=6041–50|bibcode = 2013ApOpt..52.6041H}}{{Cite journal|last1 = Lv|first1 = Wei|last2 = Phelan|first2 = Patrick E.|last3 = Swaminathan|first3 = Rajasekaran|last4 = Otanicar|first4 = Todd P.|last5 = Taylor|first5 = Robert A.|date = 2012-11-21|title = Multifunctional Core-Shell Nanoparticle Suspensions for Efficient Absorption|journal = Journal of Solar Energy Engineering|volume = 135|issue = 2|pages = 021004|doi = 10.1115/1.4007845|issn = 0199-6231}}{{Cite journal|last1 = Otanicar|first1 = Todd P.|last2 = Phelan|first2 = Patrick E.|last3 = Taylor|first3 = Robert A.|last4 = Tyagi|first4 = Himanshu|date = 2011-03-22|title = Spatially Varying Extinction Coefficient for Direct Absorption Solar Thermal Collector Optimization|journal = Journal of Solar Energy Engineering|volume = 133|issue = 2|pages = 024501|doi = 10.1115/1.4003679|issn = 0199-6231}} Graphene based nanofluid has been found to enhance Polymerase chain reaction{{cite web|url=http://iopscience.iop.org/0957-4484/23/45/455106|title=Enhancing the efficiency of polymerase chain reaction using graphene nanoflakes - Abstract - Nanotechnology - IOPscience|work=iop.org|access-date=8 June 2015}} efficiency. Nanofluids in solar collectors is another application where nanofluids are employed for their tunable optical properties.{{cite journal|last1=Sreekumar|first1=S.|last2=Shah|first2=N.|last3=Mondol|first3=J.|last4=Hewitt|first4=N.|last5=Chakrabarti|first5=S.|title=Broadband absorbing mono, blended and hybrid nanofluids for direct absorption solar collector: A comprehensive review|journal=Nano Futures|date=February 2022|volume=103|issue=2 |pages=504–515|doi=10.1088/2399-1984/ac57f7|bibcode=2022NanoF...6b2002S |s2cid=247095942 |url=https://pure.ulster.ac.uk/ws/files/99749348/SREEKUMAR_et_al_2022_Nano_Futures_10.1088_2399_1984_ac57f7.pdf }}{{cite journal|title=Nanofluid optical property characterization: towards efficient direct absorption solar collectors| doi=10.1186/1556-276X-6-225|pmid = 21711750| pmc=3211283|volume=6| issue=1|journal=Nanoscale Research Letters|page=225 | last1 = Taylor | first1 = Robert A|bibcode=2011NRL.....6..225T|year = 2011| doi-access=free}}{{cite journal|title= Nanofluid-based optical filter optimization for PV/T systems|volume=1|issue= 10|doi=10.1038/lsa.2012.34|page=e34|journal= Light: Science & Applications| last1 = Taylor | first1 = Robert A|bibcode=2012LSA.....1E..34T|date= October 2012|doi-access=free}} Nanofluids have also been explored to enhance thermal desalination technologies, by altering thermal conductivity{{cite journal | last1=Parmar | first1=Harsharaj B. | last2=Fattahi Juybari | first2=Hamid | last3=Yogi | first3=Yashwant S. | last4=Nejati | first4=Sina | last5=Jacob | first5=Ryan M. | last6=Menon | first6=Prashant S. | last7=Warsinger | first7=David M. | title=Nanofluids improve energy efficiency of membrane distillation | journal=Nano Energy | publisher=Elsevier BV | volume=88 | year=2021 | issn=2211-2855 | doi=10.1016/j.nanoen.2021.106235 | page=106235| doi-access=free | bibcode=2021NEne...8806235P }} and absorbing sunlight,{{cite journal | last1=Zhang | first1=Yong | last2=Liu | first2=Lie | last3=Li | first3=Kuiling | last4=Hou | first4=Deyin | last5=Wang | first5=Jun | title=Enhancement of energy utilization using nanofluid in solar powered membrane distillation | journal=Chemosphere | publisher=Elsevier BV | volume=212 | year=2018 | issn=0045-6535 | doi=10.1016/j.chemosphere.2018.08.114 | pages=554–562| pmid=30165282 | bibcode=2018Chmsp.212..554Z | s2cid=52138195 }} but surface fouling of the nanofluids poses a major risk to those approaches. Researchers proposed nanofluids for electronics cooling.{{Cite journal |last1=Khaleduzzaman |first1=S. S. |last2=Rahman |first2=Saidur |last3=Selvaraj |first3=Jeyraj |last4=Mahbubul |first4=I. M. |last5=Sohel |first5=M. R. |last6=Shahrul |first6=I. M. |date=2014 |title=Nanofluids for Thermal Performance Improvement in Cooling of Electronic Device |url=https://www.scientific.net/AMR.832.218 |journal=Advanced Materials Research |language=en |volume=832 |pages=218–223 |doi=10.4028/www.scientific.net/AMR.832.218 |s2cid=136011443 |issn=1662-8985}} Nanofluids also can be used in machining.{{Cite journal |last1=Vasu |first1=V. |last2=Kumar |first2=K. Manoj |date=2011-12-01 |title=Analysis of Nanofluids as Cutting Fluid in Grinding EN-31 Steel |journal=Nano-Micro Letters |language=en |volume=3 |issue=4 |pages=209–214 |doi=10.1007/BF03353674 |s2cid=135588867 |issn=2150-5551|doi-access=free |bibcode=2011NML.....3..209V }}

One project demonstrated a class of magnetically polarizable nanofluids with thermal conductivity enhanced up to 300%. Fatty-acid-capped magnetite nanoparticles of different sizes (3-10 nm) were synthesized. It showed that the thermal and rheological properties of such magnetic nanofluids are tunable by varying magnetic field strength and orientation with respect to the direction of heat flow.{{Cite journal |last1=Heysiattalab |first1=S. |last2=Malvandi |first2=A. |last3=Ganji |first3=D. D. |date=2016-07-01 |title=Anisotropic behavior of magnetic nanofluids (MNFs) at filmwise condensation over a vertical plate in presence of a uniform variable-directional magnetic field |journal=Journal of Molecular Liquids |volume=219 |pages=875–882 |doi=10.1016/j.molliq.2016.04.004}}{{Cite journal |last=Malvandi |first=Amir |date=2016-06-01 |title=Anisotropic behavior of magnetic nanofluids (MNFs) at film boiling over a vertical cylinder in the presence of a uniform variable-directional magnetic field |journal=Powder Technology |volume=294 |pages=307–314 |doi=10.1016/j.powtec.2016.02.037}}{{Cite journal |last=Malvandi |first=Amir |date=2016-05-15 |title=Film boiling of magnetic nanofluids (MNFs) over a vertical plate in presence of a uniform variable-directional magnetic field |journal=Journal of Magnetism and Magnetic Materials |volume=406 |pages=95–102 |bibcode=2016JMMM..406...95M |doi=10.1016/j.jmmm.2016.01.008}} Such response stimuli fluids are reversible and have applications in miniature devices such as micro- and nano-electromechanical systems.{{cite journal |author=J. Philip, Shima.P.D. & B. Raj |year=2006 |title=Nanofluid with tunable thermal properties |journal=Applied Physics Letters |volume=92 |issue=4 |pages=043108 |bibcode=2008ApPhL..92d3108P |doi=10.1063/1.2838304}}{{cite journal |author=Shima P.D.and J. Philip |year=2011 |title=Tuning of Thermal Conductivity and Rheology of Nanofluids using an External Stimulus |journal=J. Phys. Chem. C |volume=115 |issue=41 |pages=20097–20104 |doi=10.1021/jp204827q}}

A 2013 study considered the effect of an external magnetic field on the convective heat transfer coefficient of water-based magnetite nanofluid experimentally under laminar flow regime. It obtained up to 300% enhancement at Re=745 and magnetic field gradient of 32.5 mT/mm. The effect of the magnetic field on pressure was not as significant.{{cite journal |last1=Azizian |first1=R. |last2=Doroodchi |first2=E. |last3=McKrell |first3=T. |last4=Buongiorno |first4=J. |last5=Hu |first5=L.W. |last6=Moghtaderi |first6=B. |year=2014 |title=Effect of magnetic field on laminar convective heat transfer of magnetite nanofluids |journal=Int. J. Heat Mass |volume=68 |pages=94–109 |doi=10.1016/j.ijheatmasstransfer.2013.09.011|bibcode=2014IJHMT..68...94A }}

A nanofluid-based ultrasensitive optical sensor changes its colour on exposure to low concentrations of toxic cations.{{cite journal |last1=Mahendran |first1=V. |year=2013 |title=Spectral Response of MagneticNanofluid to Toxic Cations |journal=Appl. Phys. Lett. |volume=102 |issue=16 |page=163109 |bibcode=2013ApPhL.102p3109M |doi=10.1063/1.4802899}} The sensor is useful in detecting minute traces of cations in industrial and environmental samples. Existing techniques for monitoring cations levels in industrial and environmental samples are expensive, complex and time-consuming. The sensor uses a magnetic nanofluid that consists of nano-droplets with magnetic grains suspended in water. In a fixed magnetic field, a light source illuminates the nanofluid, changing its colour depending on the cation concentration. This color change occurs within a second after exposure to cations, much faster than other existing cation sensing methods.

Such responsive nanofluids can detect and image defects in ferromagnetic components. The so-called photonic eye is based on a magnetically polarizable nano-emulsion that changes colour when it comes into contact with a defective region in a sample. The device could monitor structures such as rail tracks and pipelines.{{cite journal |last1=Mahendran |first1=V. |year=2012 |title=Nanofluid based opticalsensor for rapid visual inspection of defects in ferromagnetic materials |journal=Appl. Phys. Lett. |volume=100 |issue=7 |page=073104 |bibcode=2012ApPhL.100g3104M |doi=10.1063/1.3684969}}{{cite web |title=Nanofluid sensor images defects |url=http://nanotechweb.org/cws/article/tech/48783 |access-date=8 June 2015 |work=nanotechweb.org}}

Nanolubricants modify oils used for engine and machine lubrication.{{cite journal |last1=Rasheed |first1=A.K. |last2=Khalid |first2=M. |last3=Javeed |first3=A. |last4=Rashmi |first4=W. |last5=Gupta |first5=T.C.S.M. |last6=Chan |first6=A. |date=November 2016 |title=Heat transfer and tribological performance of graphene nanolubricant in an internal combustion engine |journal=Tribology International |volume=103 |pages=504–515 |doi=10.1016/j.triboint.2016.08.007}} Materials including metals, oxides and allotropes of carbon have supplied nanoparticles for such applications. The nanofluid enhances thermal conductivity and anti-wear properties. Although MoS₂, graphene, and Cu-based fluids have been studied extensively, fundamental understanding of underlying mechanisms is absent.

MoS₂ and graphene work as third body lubricants, essentially acting as ball bearings that reduce the friction between surfaces.{{Cite book |last1=Anis |first1=Mohab |url={{google books|plainurl=yes|id=1aGwDQAAQBAJ}} |title=Nanovate: Commercializing Disruptive Nanotechnologies |last2=AlTaher |first2=Ghada |last3=Sarhan |first3=Wesam |last4=Elsemary |first4=Mona |date=2016-12-08 |publisher=Springer |isbn=978-3-319-44863-3 |language=en}}{{Cite book |last1=Fox-Rabinovich |first1=German |url={{google books|plainurl=y|id=YIKLTLgtAscC}}|title=Self-Organization During Friction: Advanced Surface-Engineered Materials and Systems Design |last2=Totten |first2=George E. |date=2006-09-18 |publisher=CRC Press |isbn=978-1-4200-1786-1 |language=en}} This mechanism requires sufficient particles to be present at the contact interface. The beneficial effects diminish because sustained contac pushes away the third body lubricants.

Other nanolubricant approaches, such as magnesium silicate hydroxides (MSH) rely on nanoparticle coatings by synthesizing nanomaterials with adhesive and lubricating functionalities. Research into nanolubricant coatings has been conducted in both the academic and industrial spaces.Rudenko P (Washington SU, Chang Q, Erdemir A (Argonne NL. Effect of Magnesium Hydrosillicate on Rolling Element Bearings. In: STLE 2014 Annual Meeting; 2014.Chang Q, Rudenko P (Washington SU, Miller D, et al. Diamond like Nanocomposite Boundary Films from Synthetic Magnesium Silicon Hydroxide (MSH) Additives.; 2014. Nanoborate additives as well as mechanical model descriptions of diamond-like carbon (DLC) coating formations have been developed.{{Cite journal |last1=Erdemir |first1=Ali |last2=Ramirez |first2=Giovanni |last3=Eryilmaz |first3=Osman L. |last4=Narayanan |first4=Badri |last5=Liao |first5=Yifeng |last6=Kamath |first6=Ganesh |last7=Sankaranarayanan |first7=Subramanian K. R. S. |date=2016-08-04 |title=Carbon-based tribofilms from lubricating oils |url=https://www.nature.com/articles/nature18948 |journal=Nature |language=en |volume=536 |issue=7614 |pages=67–71 |doi=10.1038/nature18948 |pmid=27488799 |bibcode=2016Natur.536...67E |issn=0028-0836}} Companies such as TriboTEX provide commercial formulations of synthesized MSH nanomaterial coatings for vehicle engine and industrial applications.{{Cite web |title=TriboTEX REVERSE WEAR: run longer, stronger, and cleaner w/ nanotech |url=https://www.tribotex.com/ |access-date=2024-06-17 |website=TriboTEX |language=en-US}}

Many researches claim that nanoparticles can be used to enhance crude oil recovery.{{Cite journal |last1=Suleimanov |first1=B.A. |last2=Ismailov |first2=F.S. |last3=Veliyev |first3=E.F. |date=2011-08-01 |title=Nanofluid for enhanced oil recovery |url=https://figshare.com/articles/journal_contribution/11346632 |journal=Journal of Petroleum Science and Engineering |language=en |volume=78 |issue=2 |pages=431–437 |bibcode=2011JPSE...78..431S |doi=10.1016/j.petrol.2011.06.014 |issn=0920-4105 |s2cid=95822692 |doi-access=free}}

Magnetic nanoparticle clusters or magnetic nanobeads of size 80–150 nanometers form ordered structures along the direction of an external magnetic field with a regular interparticle spacing on the order of hundreds of nanometers resulting in strong diffraction of visible light.{{cite journal |last1=He |first1=Le |last2=Wang |first2=Mingsheng |last3=Ge |first3=Jianping |last4=Yin |first4=Yadong |date=18 September 2012 |title=Magnetic Assembly Route to Colloidal Responsive Photonic Nanostructures |url=https://escholarship.org/uc/item/1274g7zx |journal=Accounts of Chemical Research |volume=45 |issue=9 |pages=1431–1440 |doi=10.1021/ar200276t |pmid=22578015}}http://nanos-sci.com/technology.html Properties and use of magnetic nanoparticle clusters (magnetic nanobeads)

Nanoelectrofuel-based flow batteries ((NFB) have been claimed to store 15 to 25 times as much energy as traditional flow batteries. The Strategic Technology Office of the U.S. Defense Advanced Research Projects Agency (DARPA) is exploring military’s deployment of NFB in place of conventional lithium-ion batteries.{{Cite web |last=CHARETTE |first=ROBERT N. |date=24 December 2023 |title=Can Flow Batteries Finally Beat Lithium? - IEEE Spectrum |url=https://spectrum.ieee.org/flow-battery-2666672335 |access-date=2024-06-17 |website=IEEE |language=en}}

The nanofluid particles undergo redox reactions at the electrode. Particles are engineered to remain suspended indefinitely, comprising up to 80 percent of the liquid’s weight with the viscosity of motor oil. The particles can be made from inexpensive minerals, such as ferric oxide (anode) and gamma manganese dioxide (cathode). The nanofluids use a nonflammable aqueous suspension.

As of 2024 DARPA-funded Influit claimed to be developing a battery with an energy density of 550-850 wh/kg, higher than conventional lithium-ion batteries. A demonstration battery operated successfully between −40 °C and 80 °C.

Discharged nanofluids could be recharged while in a vehicle or after removal at a service station. Costs are claimed to be comparable to lithium ion. An EV-battery sized fuel reservoir (80 gallons) was expected to provide range comparable to a conventional gasoline vehicle. Fluids that escape, e.g., following a crash, turn into a pastelike substance, which can be removed and reused safely. Flow batteries also produce less heat, reducing their thermal signature for military vehicles.

A 30-lab study reported that "no anomalous enhancement of thermal conductivity was observed in the limited set of nanofluids tested in this exercise".{{Cite journal|last1=Buongiorno|first1=Jacopo|last2=Venerus|first2=David C.|last3=Prabhat|first3=Naveen|last4=McKrell|first4=Thomas|last5=Townsend|first5=Jessica|last6=Christianson|first6=Rebecca|last7=Tolmachev|first7=Yuriy V.|last8=Keblinski|first8=Pawel|last9=Hu|first9=Lin-wen|last10=Alvarado|first10=Jorge L.|last11=Bang|first11=In Cheol|date=2009-11-01|title=A benchmark study on the thermal conductivity of nanofluids|journal=Journal of Applied Physics|volume=106|issue=9|pages=094312–094312–14|doi=10.1063/1.3245330|bibcode=2009JAP...106i4312B|issn=0021-8979|hdl=1721.1/66196|hdl-access=free}} The COST funded research programme, Nanouptake (COST Action CA15119) was conducted with the intention "develop and foster the use of nanofluids as advanced heat transfer/thermal storage materials to increase the efficiency of heat exchange and storage systems". One 5-lab study reported that "there are no anomalous or unexplainable effects".{{Cite journal|last1=Buschmann|first1=M. H.|last2=Azizian|first2=R.|last3=Kempe|first3=T.|last4=Juliá|first4=J. E.|last5=Martínez-Cuenca|first5=R.|last6=Sundén|first6=B.|last7=Wu|first7=Z.|last8=Seppälä|first8=A.|last9=Ala-Nissila|first9=T.|date=2018-07-01|title=Correct interpretation of nanofluid convective heat transfer|journal=International Journal of Thermal Sciences|volume=129|pages=504–531|doi=10.1016/j.ijthermalsci.2017.11.003|issn=1290-0729|doi-access=free|bibcode=2018IJTS..129..504B |hdl=10234/174682|hdl-access=free}}

Despite these apparently conclusive experimental investigations theoretical papers continue to claim anomalous enhancement,{{Cite journal|last=Bahiraei|first=Mehdi|date=2015-09-01|title=Effect of particle migration on flow and heat transfer characteristics of magnetic nanoparticle suspensions|journal=Journal of Molecular Liquids|volume=209|pages=531–538|doi=10.1016/j.molliq.2015.06.030}}{{Cite journal|last1=Malvandi|first1=A.|last2=Ghasemi|first2=Amirmahdi|last3=Ganji|first3=D. D.|date=2016-11-01|title=Thermal performance analysis of hydromagnetic Al2O3-water nanofluid flows inside a concentric microannulus considering nanoparticle migration and asymmetric heating|journal=International Journal of Thermal Sciences|volume=109|pages=10–22|doi=10.1016/j.ijthermalsci.2016.05.023}}{{Cite journal|last=Bahiraei|first=Mehdi|date=2015-05-01|title=Studying nanoparticle distribution in nanofluids considering the effective factors on particle migration and determination of phenomenological constants by Eulerian–Lagrangian simulation|journal=Advanced Powder Technology|series=Special issue of the 7th World Congress on Particle Technology|volume=26|issue=3|pages=802–810|doi=10.1016/j.apt.2015.02.005}}{{Cite journal|last1=Pakravan|first1=Hossein Ali|last2=Yaghoubi|first2=Mahmood|date=2013-06-01|title=Analysis of nanoparticles migration on natural convective heat transfer of nanofluids|journal=International Journal of Thermal Sciences|volume=68|pages=79–93|doi=10.1016/j.ijthermalsci.2012.12.012|bibcode=2013IJTS...68...79P }}{{Cite journal|last1=Malvandi|first1=A.|last2=Moshizi|first2=S. A.|last3=Ganji|first3=D. D.|date=2016-01-01|title=Two-component heterogeneous mixed convection of alumina/water nanofluid in microchannels with heat source/sink|journal=Advanced Powder Technology|volume=27|issue=1|pages=245–254|doi=10.1016/j.apt.2015.12.009}}{{Cite journal|last1=Malvandi|first1=A.|last2=Ganji|first2=D. D.|date=2014-10-01|title=Brownian motion and thermophoresis effects on slip flow of alumina/water nanofluid inside a circular microchannel in the presence of a magnetic field|journal=International Journal of Thermal Sciences|volume=84|pages=196–206|doi=10.1016/j.ijthermalsci.2014.05.013|bibcode=2014IJTS...84..196M }}{{Cite journal|last1=Bahiraei|first1=Mehdi|last2=Abdi|first2=Farshad|date=2016-10-15|title=Development of a model for entropy generation of water-TiO2 nanofluid flow considering nanoparticle migration within a minichannel|journal=Chemometrics and Intelligent Laboratory Systems|volume=157|pages=16–28|doi=10.1016/j.chemolab.2016.06.012}} particularly via Brownian and thermophoretic mechanisms. Brownian diffusion is due to the random drifting of suspended nanoparticles in the base fluid which originates from collisions between nanoparticles and liquid molecules. Thermophoresis induces nanoparticle migration from warmer to colder regions, again due to such collisions. A 2017 study considered the mismatch between experimental and theoretical results. It reported that Brownian motion and thermophoresis effects have no significant effects: their role is often amplified in theoretical studies due to the use of incorrect parameter values.{{Cite journal |last1=Myers |first1=Tim G. |last2=Ribera |first2=Helena |last3=Cregan |first3=Vincent |date=2017-08-01 |title=Does mathematics contribute to the nanofluid debate? |journal=International Journal of Heat and Mass Transfer |volume=111 |pages=279–288 |arxiv=1902.09346 |doi=10.1016/j.ijheatmasstransfer.2017.03.118 |bibcode=2017IJHMT.111..279M |issn=0017-9310 |s2cid=119067497}} Experimental validation of these assertions came in 2018{{Cite journal|last1=Alkasmoul|first1=Fahad S.|last2=Al-Asadi|first2=M. T.|last3=Myers|first3=T. G.|last4=Thompson|first4=H. M.|last5=Wilson|first5=M. C. T.|date=2018-11-01|title=A practical evaluation of the performance of Al2O3-water, TiO2-water and CuO-water nanofluids for convective cooling|journal=International Journal of Heat and Mass Transfer|volume=126|pages=639–651|doi=10.1016/j.ijheatmasstransfer.2018.05.072|bibcode=2018IJHMT.126..639A |issn=0017-9310|url=http://eprints.whiterose.ac.uk/131074/1/Alkasmoul-2018-IJHMT-nanofluids-AAM.pdf|hdl=2072/445790|s2cid=126074065 |hdl-access=free}} Brownian diffusion as a cause for enhanced heat transfer is dismissed in the discussion of the use of nanofluids in solar collectors.{{Cn|date=June 2024}}

• Argonne National Laboratory
• Flow battery
• Fluid dynamics
• Heat transfer
• Nanophase material
• Surface-area-to-volume ratio
• Surfactant
• Therminol

{{Reflist}}

• [https://www.youtube.com/watch?v=uZwNDtfUb0A Magnetically responsive photonic crystals nanofluid (video)] produced by Nanos scientificae

• {{Cite journal |last1=Khashi’ie |first1=Najiyah Safwa |last2=Md Arifin |first2=Norihan |last3=Nazar |first3=Roslinda |last4=Hafidzuddin |first4=Ezad Hafidz |last5=Wahi |first5=Nadihah |last6=Pop |first6=Ioan |date=January 2019 |title=A Stability Analysis for Magnetohydrodynamics Stagnation Point Flow with Zero Nanoparticles Flux Condition and Anisotropic Slip |journal=Energies |language=en |volume=12 |issue=7 |pages=1268 |doi=10.3390/en12071268 |doi-access=free |issn=1996-1073}}

European projects:

• [https://web.archive.org/web/20100814163218/http://www.nanohex.eu/ NanoHex is a European project developing industrial-class nanofluid coolants]

Category:Nanoparticles

Category:Fluid mechanics

Category:Heat transfer

Category:Nanomaterials