Study on boiling heat transfer of water–TiO2 and water–MWCNT nanofluids based laminar jet impingement on heated steel surface

The present study aims at investigating the boiling heat transfer aspect of water–TiO2 and water- multi-walled carbon nanotubes (water–MWCNT) nanofluids based laminar jet cooling of heated horizontal steel surface. Experimental results show that cooling rate is enhanced by using nanofluids when compared to water. A one-dimensional finite volume inverse heat transfer model is developed to predict the total heat flux removal rate from the hot steel surface. It is also observed in the present case that the shift from “film boiling” to “transition boiling” regime occurs earlier for nanofluid than that of water jet cooled surface. An order of magnitude analysis shows that the shift may be attributed to the vapor film instability in presence of nanoparticle deposition. However, only marginal variation of critical heat flux (CHF) is observed in case of nanofluid jet when compared to water jet.

In this work, the boiling heat transfer aspect of water–TiO2 and water– multi-walled carbon nanotubes (water–MWCNT) nanofluids based laminar jet cooling of heated horizontal steel surface is investigated. Figure below shows the cooling curve of the hot steel plate cooled by water, 0.1 wt. % water–TiO2 and 0.01 wt. % water–MWCNT nanofluids. It is observed from the figure that the cooling rate is enhanced by using nanofluids when compared to water.Figure optionsDownload as PowerPoint slideHighlights
► Laminar jet cooling of heated horizontal steel surface studied experimentally.
► Boiling heat transfer behavior of TiO2 and MWCNT nanofluids compared with water.
► Heat removal rate calculated from 1D finite volume inverse heat transfer model.
► Cooling rate is enhanced by using nanofluid jets.
► Shift from “film” to “transition” boiling regime occurs earlier for nanofluid.