New Achievements in Fe3O4 Nanofluid Fully Developed Forced Convection Heat Transfer under the Effect of a Magnetic Field: An Experimental Study

Abstract

Fe3O4 nanofluid fully developed forced convection inside a copper tube is empirically investigated under the effect of a magnetic field. All of the investigations are performed under laminar flow regime (670≤Re≤1700) and thermal boundary conditions of the tube with uniform thermal flux. The tube is under the effect of a magnetic field in certain points. This research aims to study the effect of various parameters, namely use of nanofluid, nanoparticles volume percent, Reynolds number of the flow, constant magnetic field, and alternating magnetic field with various frequencies on flow behavior. To validate the experiment set-up, distilled water is utilized as working fluid. The results are compared with Shah’s equation and acceptable agreements are achieved. The results suggest that owing to complex convectional flows developed in the fluid as a result of Fe3O4 nanoparticles-magnetic field interaction, increased alternating frequency of the magnetic field and increased volume fraction lead to increase heat transfer to maximum value 4.62. As Reynolds number increases, the rate of the said increase is reduced and reached to 0.29. At a constant Reynolds number, increased frequency of the alternating magnetic field results in an increased local heat transfer coefficient. However, this increase is unproportional to increase in frequency. In high frequencies, increased frequency leads to a slight increase in the heat transfer coefficient.