Variable heat source in stagnation-point unsteady flow of magnetized Oldroyd-B fluid with cubic autocatalysis chemical reaction

Abstract

Understanding the flow behavior of non-Newtonian fluids required more research in terms of various aspects. Because the role of heat transfer in non-Newtonian flows is dominant due to its importance in technology. For these benefits, a theoretical investigation is carried out to analyze the time-dependent flow of non-Newtonian fluid with a focus on thermal and solutal transport. In the present study, we formulate a mathematical model for Oldroyd-B fluid by taking into account the effect of magnetic field. The governing flow field equations are constructed with the help of the rheological expression of Oldroyd-B fluid model. For physical relevance, the effects of non-uniform heat source/sink, Joule heating and thermal radiation with homogeneous-heterogeneous chemical reactions have been incorporated in stagnation point flow towards a stretching cylinder to modify the energy and concentration distributions. The highly non-linear ordinary differential equations are tackled analytically through the optimal homotopy analysis method (OHAM). Study reveals that, the strength of homogeneous and heterogeneous reactions leads to enhanced the concentration of the catalyst at the surface. Furthermore, the non-uniform heat source/sink parameter acts like a major controlling parameter for the heat transportation rate, and heat transport is also influenced by the surface-dependent heat source/sink.

Keywords

• Axisymmetric flow
• Oldroyd-B fluid
• Non-uniform heat source/sink
• Homogeneous-heterogeneous reactions
• Stagnation point flow
• Joule heating