Characteristics of ferrofluid flow over a stretching sheet with suction and injection

Ferrofluid is a liquid that becomes magnetized in the presence of a magnetic field. Recently, ferrofluids have attracted the attention of researchers due to their paramagnetic properties. Many applications have conducted in electronic devices, mechanical engineering, materials science research and loudspeakers. In this paper, microstructure and inertial characteristics of a magnetite ferrofluid over a stretching sheet utilizing effective thermal conductivity model are studied through two semi-analytical methods which are homotopy perturbation method (HPM) and Akbari-Ganji's method (AGM). It is assumed that Fe3O4 as nanoparticle and water as a base fluid being together nanofluid model formularized by Tiwari-Das model. The effect of related parameters on stream function, velocity, micro-rotation velocity and temperature have obtained for positive and negative mass transfer flow. Results show that the velocity of the fluid in the vicinity of the sheet is maximized and decreases by moving away from the sheet. A significant variation in the behavior of stream function between the positive and negative mass transfer flow over a sheet are exhibited. However, such a behavior is attenuated after a certain distance from the sheet and then stream function is uniformed. Also, micro polar ferrofluid has the higher velocity than classical nanofluid. Furthermore, comparison of the results of this study with other researchers shows that the applied methods are efficient and useful for calculating the parameters of the present problem and have acceptable accuracy.