Multiphysics computational study of coupled analysis of thermal energy and mass transfer in a non-Newtonian fluid under chemical reaction

Thermal and solute transport enhancement is a requirement of several industrial and engineering processes like thermal and cooling systems, thermal radiators, nuclear reactor cooling, HVAC and refrigeration, etc. The rheological constitutive relations, the Stefan-Boltzmann law for thermal radiation effects, Ohm's law, and a set of Maxwell equations, together with conservation laws in the presence of magnetic body and buoyancy forces, are used to develop the governing equations. The coupled momentum, energy, and concentration equations are simplified using boundary-layer approximations. The resulting partial differential equations are reduced by similarity transformation to a dimensionless system, which is then numerically solved using the finite element method (FEM). The linear shape functions are used for approximating the solutions in a one-dimensional domain. The stiffness elements are used in the Galerkin approximations. Picard linearization is an effective technique for nonlinear algebraic systems that converges quickly when functions have a linear shape. Therefore, the Picard approach is implemented in this case. FEM solutions are further used for capturing thermal enhancement in both mono and hybrid nanofluids. The resulting nonlinear algebraic system is then linearized using Picard linearization and solved under a convergence tolerance of 10−5. The present results are validated by comparing with already published benchmark46. To clarify the impact of important physical parameters on thermal transport properties, parametric simulations are carried out. Temperature distribution decreases when the thermal radiation parameter increases because an increase in $$Nr$$ corresponds to an increase in intensity of thermal radiation, and an increase in thermal radiation implies an increase in electromagnetic waves that escape heat away from the fluid.