Entropy generation analysis of CNT-based nanofluid flows induced by a moving plate

Abstract

Carbon nanotubes have garnered considerable interest from academia and industry due to their unique properties and potential applications. This study examines fluid flow induced by a plate moving at a constant velocity towards/receding from normal stagnation point flow. The plate's surface is immersed with ethylene glycol and two types of carbon nanotubes: single-walled and multi-walled. The Reynolds number, proportional to the plate's velocity, governs the flow. Thermal transport analysis includes Ohmic heating, heat source/sink effects for constant wall temperature and prescribed surface temperature, and entropy generation analysis. Similarity ansatz is used to obtain non-dimensional ordinary differential equations, and numerical and asymptotic solutions are computed using MATLAB's bvp4c routine (finite difference-based approach). By varying the relevant parameters, the study interprets the behavior of entropy generation, Bejan number, skin frictions, Nusselt number, flow, and energy profiles. The numerical solutions are observed to match their asymptotic behaviors within an intermediate range of small and large Reynolds numbers for the wall stress parameter. The magnetic parameter produces a resistive force that reduces fluid flow but enhances the system's energy. Moreover, understanding the flow and heat transfer characteristics of CNT-based nanofluids induced by a moving plate can provide insights into the design and optimization of thermal systems, including efficient heat exchangers used in power generation, chemical, and petrochemical industries.