Nanofluids flow over a permeable unsteady stretching surface with non-uniform heat source/sink in the presence of inclined magnetic field

Author

Department of Mathematics, Faculty of Education, Ain Shams University, El Makrizy Street, Roxy, Heliopolis, Cairo 11341, Egypt

https://doi.org/10.1186/s42787-019-0002-4

Abstract

eable surface in the presence of an inclined magnetic field and nonuniform heat source/sink. Four different types of nanoparticles, namely silver Ag, copper Cu, alumina Al2O3, and titania TiO2, are considered by using water as a base
fluid with the Prandtl number Pr = 6.785. The governing partial differential equations
are transformed to coupled non-linear ordinary differential equations by appropriate
similarity transformation. Furthermore, the similarity equations are solved numerically
by using the fourth-order Runge-Kutta integration scheme with Newton Raphson
shooting method. A comparison of obtained numerical results is made with
previously published results in some special cases, and excellent agreement is noted.
Numerical results for velocity and temperature profiles as well as skin friction
coefficient and local Nusselt number are discussed for various values of physical
parameters. It tends to be discovered that, the magnetic field inclination angle γ has
the capability to strengthens the magnetic field and reduce the velocity profile of
the flow. Also, it can be found that, by using various types of nanofluids, velocity and
temperature distributions change, which means that the nanofluids are important in
the cooling and heating processes. The thermal boundary layer thickness is related
to the increased thermal conductivity of different types of nanofluids, i.e., the
minimum (maximum) value of the temperature is obtained by adding titanium oxide
(silver) to the fluid as the nanoparticles.

Keywords