Dynamics of Soret and Dufour effects on oscillatory flow of couple stress fluid due to stretchable curved surface

Abstract

In this theoretical study, we have discussed the impacts of Soret and Dufour on the flow of time-dependent couple stress fluid across a stretchable curved oscillatory surface with magnetic field. The to and fro motion of the surface causes the flow phenomenon. The boundary layer flow equations depicting the flow phenomena are expressed in mathematical form by means of a curvilinear coordinates system along with some suitable similarity variables. The developed flow equations in the form of partial differential equations are then solved analytically by utilizing a valuable method called the homotopy analysis method (HAM). A detailed examination is performed to evaluate the influence of various involved parameters namely, the non-dimensional radius of curvature, couple stress parameter, magnetic parameter, the relation of the parameter of the surface oscillating frequency to its stretching rate constant and Soret and Dufour numbers on velocity field, pressure distribution, concentration and temperature distribution, rate of heat transfer, coefficient of skin friction, and rate of mass transport via graphs and are explained in detail. It is confirmed that the amplitude of velocity and pressure distribution exhibits reducing behavior with higher values of the couple stress parameter. The concentration and temperature profiles also diminish with varying time instants.