Dissipative hybrid nanofluid flow in a non-Newtonian (Casson) model within the context of a Riga plate experiencing thermal radiation and heat source/sink effects

In recent years, the application of electromagnetic actuators such as the Riga plate has gained considerable attention in enhancing the control and efficiency of fluid flow systems, particularly in thermal management technologies. The present study explores the thermodynamic performance of hybrid nanofluids engineered by dispersing two distinct types of nanoparticles into a base fluid flowing over a Riga plate under the influence of thermal radiation and stretching/shrinking boundary conditions. The use of a Riga plate introduces a Lorentz force via a magneto-hydrodynamic (MHD) mechanism, which actively modifies the velocity and temperature distributions within the flow field. Simultaneously, the presence of hybrid nanofluids significantly improves the heat transfer capabilities due to their superior thermal conductivity compared to conventional fluids or mono-nanofluids. The two nanoparticles investigated in this work are Silver (Ag) and Iron oxide (Fe 3 O 4 ), using a mixture of ethylene glycol (EG) as the base fluid. The result was a mathematical flow model expressed in terms of partial differential equations (PDEs) that are extremely nonlinear. Ordinary differential equations (ODEs) were created by reducing the partial differential equations and their boundary conditions using an appropriate similarity variable. The Galerkin-weighted residual Method (GWRM) is then used to solve the resultant nonlinear system of equations using Mathematica 11.3 software. In comparison to the NFs, the HNFs is shown to have a greater heat transfer rate. Results indicate that the hybrid nanofluid achieves a 19.4% increase in heat transfer rate compared to single-particle nanofluids under similar flow conditions. Additionally, an increase in the magnetic parameter enhances thermal dispersion by 12.8%, while increasing the thermal radiation parameter results in a 15.6% boost in heat transfer. These findings demonstrate the significant potential of HNFs for improving thermal efficiency in engineering applications such as solar energy harvesting and microfluidic cooling systems, where enhanced heat transfer is critical.