Case Studies in Thermal Engineering (Sep 2023)

Nonlinear free convective with longitudinal slits in the presence of super-hydrophobic and non-hydrophobic microchannels in a suspension of nanoparticles: Multi-Linear Regression Analysis

  • Kezheng Zhang,
  • C.S.K. Raju,
  • Kiran Sajjan,
  • Bander Almutairi,
  • Nehad Ali Shah,
  • Sayed M. Eldin

Journal volume & issue
Vol. 49
p. 103138

Abstract

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Super hydrophobic microchannels have extremely high water repellency, and such a property is reliant on a set of factors, namely the surface construction and the surface energy. The surface energy can be depressed either by exhausting a chemical film that is coated or stuck to the surface or by adjusting the existing surface interaction or by producing micro- and nanotextures. Further, due to the latter reason of inducing super hydrophobic properties, a study of manufacturing processes to produce surface textures becomes critical to the understanding of the area. The latest generative manufacturing techniques, such as 3-D (three-dimensional) printing, laser machining, and so on are new-generation processes that can be used to write over surfaces at different resolutions. Viewing into this, the natural convection of conductive nanofluids in vertical slot micro-channels with super-hydrophobic slips and temperature jumps, the non-linear Boussinesq approximation approach provides an accurate solution. One inner surface of the microchannel surface has been physically modified to exhibit temperature jumps and super-hydrophobic velocity slips. The transverse magnetic field indicates the direction of flow. In two different physical situations, it is possible to get a single answer. Type I involves heating the super-hydrophobic surface without heating the non-slip surface, and Type II involves heating the non-slip surface without heating the super-hydrophobic surface. Velocity slip reduces the Type I Nusselt number and increases the Type II Nusselt number in both situations. The temperature jump factor has the opposite effect. In contrast to the change in linear density with temperature, the non-linear density change with temperature causes an increase in flow and velocity. It is observed that more slip coefficient corresponds to less Nusselt number and more slip velocity, especially at larger magnetic parameter values to increase the heat transfer rate from the microchannel walls. It is recommended to use Al2O3-water nanofluid the nanofluid composed of nanoparticles with higher thermal conductivity. Applications of the subject include anti-wetting micro technology, electrolytic cell maintenance, micro-hydraulic devices, and micro-electronic heat dissipation.

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