This study aims at experimentally investigating the influence of magnetic field on
the rheological behavior of water–carbon nanotube (CNT)/magnetite (Fe3O4) nanofluid.
Tetramethylammonium hydroxide (TMAH) and Gum arabic (GA) are respectively used
to stabilize the nanofluid. Scanning Electron Microscope (SEM), Dynamic Light Scattering
(DLS) and X-ray Diffraction (XRD) methods were used to characterize the prepared
nanofluid samples. Experiments were performed to evaluate the viscosity of water–
CNT/magnetite nanofluid in the shear rate range of 1–100 s−1, volume fraction range
of 0.5-1.5%, and magnetic field strength range of 0–480 mT. It was found that the
presence of an external magnetic field causes an increase in the viscosity of the water–
CNT/magnetite nanofluid. In addition, the results depicted that the viscosity of the
nanofluid augments by boosting the concentration of the nano-materials. Moreover, it
was reported that increasing the magnetic field strength to more than 360 mT has a
negligible influence on the augmentation of nanofluid viscosity. Furthermore, the non-
Newtonian shear thinning behavior was depicted because of the decrease in viscosity
with intensifying the shear rates.