experimental study of nanofluids flow in a micromodel as porous medium

for better understanding the effect of nanofluid flow in a porous medium, a set of experiments were conducted on a horizontal glass micromodel for al2o3-water nanofluids. to characterize the flow of nanofluids the same experiment was done by pure water. the glass micromodel was constructed by a photolithography technique. the al2o3-water nanofluids were produced by a two-step method and no surfactant or ph changes were used. the nanofluids were made in different volume fractions of 0.1%, 0.5%, and 1%. the experimental results show that the pressure drop of nanofluids through the micromodel increases up to 43% at volume concentration of 0.01. moreover, the al2o3-water nanofluids behave like a newtonian fluid and follow darcy’s law at low reynolds numbers. the permeability of the porous medium has been evaluated in different volume fraction of nanofluids and pure water. the results reveal that the assessed permeability doesn’t change significantly in various volume concentrations of nanoparticles in the constructed micromodel. a semi analytical correlation was proposed for calculating the permeability of such porous medium.