This research paper explores the influence of first-order chemical reactions on the sustainable properties of electrically conducting magnetohydrodynamic (MHD) fluids in a vertical channel with the unique characteristics of Jeffrey fluid flow. The mathematical model of MHD flow with Jeffrey fluid and chemical reaction incorporates the impacts of viscous dissipation, Joule heating, and a non-Newtonian fluid model with viscoelastic properties in the flow regions. The governing equations of the flow field were solved using the finite difference method, and the impacts of flow parameters on the flow characteristics were discussed numerically using a graphical representation. It’s revealed that increasing the Jeffrey parameter results in a decline in the velocity field profiles. Also, species concentration field profiles decline with higher values of the destruction chemical reaction parameter. The findings of this study have significant implications for various engineering applications, including energy generation, aerospace engineering, and material processing. Additionally, the inclusion of Jeffrey’s fluid flow introduces a viscoelastic component, enhancing the complexity of the fluid dynamics.

Considering the application of the polymer electrolyte membrane fuel cell (PEMFC), the separator thickness plays a significant role in determining the weight, volume, and costs of the PEMFC. In addition, thermal management, i.e., temperature distribution is also important for the PEMFC system to obtain higher performance. However, there were few reports investigating the relation between the temperature profile and the power generation characteristics e.g., the current density distribution of PEMFC operated at higher temperatures (HT-PEMFC). This paper aims to study the impact of separator thickness on the temperature profile and the current density profile of HT-PEMFC. The impact of separator thickness on the gases i.e., H₂, O₂ profile of HT-PEMFC numerically was also studied using CFD software COMSOL Multiphysics in the paper. In the study, the operating temperature and the relative humidity (RH) of the supply gas were varied with the separator thickness of 2.0 mm, 1.5 mm, and 1.0 mm, respectively. The study revealed that the optimum thickness was 2.0 mm to realize higher power generation of HT-PEMFC. The heat capacity of the separator thickness of 2.0 mm was the biggest among the separators investigated in this study, resulting in the dry-up of PEM and catalyst layer was lower compared to the thinner separator thickness. It also clarified the effects of separator thickness of profile gases, e.g., O₂, H₂O, and current density profile became larger under the higher temperature and the lower RH conditions.