Analysis of hydromagnetic boundary layer flow and heat transfer of nanofluids

Abstract

Magnetohydrodynamic (MHD) boundary layer flow of an electrically conducting viscous incompressible fluid with a convective surface boundary condition is frequently encountered in many industrial and technological applications such as extrusion of plastics in the manufacture of Rayon and Nylon, the cooling of reactors, purification of crude oil, textile industry, polymer technology, metallurgy, geothermal engineering, liquid metals and plasma flows, boundary layer control in aerodynamics and crystal growth etc. Nanofluid is envisioned to describe a fluid in which nanometer-sized particles are suspended in conventional heat transfer base fluids to improve their thermal physical properties. Nanoparticles are made from various materials, such as metals (Cu, Ag, Au, Al, Fe), oxide ceramics (Al2O3, CuO, TiO2), nitride ceramics (AlN, SiN), carbide ceramics (SiC, tiC), semiconductors, carbon nanotubes and composite materials such as alloyed nanoparticles or nanoparticle core–polymer shell composites. It is well known that, conventional heat transfer fluids, such as oil, water, and ethylene glycol, in general, have poor heat transfer properties compared to those of most solids. Nanofluids have enhanced thermophysical properties such as thermal conductivity; thermal diffusivity, viscosity and convective heat transfer coefficients compared with those of base fluids like oil or water. Owing to their enhanced properties, nanofluids can be used in a plethora of technical and biomedical applications such as nanofluid coolant: electronics cooling, vehicle cooling, transformer cooling, computers cooling and electronic devices cooling; medical applications: magnetic drug targeting, cancer therapy and safer surgery by cooling; process industries; materials and chemicals: detergency, food and drink, oil and gas, paper and printing and textiles.