Effect of simultaneous application of chaotic laminar flow of nanofluid and non-uniform magnetic field on the entropy generation and energetic/exergetic efficiency

This work aims to characterize the heat exchange system efficiency and entropy generation of nanofluid forced convection flow with chaotic perturbations influenced by a non-uniform magnetic field. The study investigates numerically the effects of combined passive/active methods presented in terms of chaotic advection, nanoparticles and non-uniform magnetic field on the fluid flow performances. Adopted parameters for the characterization are the convection heat transfer coefficient, field synergy principle, entropy production and efficiency according to the first and second law of thermodynamics. Several parameters were used to evaluate the current study, such as Hartmann and Reynolds numbers, concentration of nanoparticles as well as the mode of application and orientation of the magnetic field. The main results show that the co-effect of the magnetic intensity (Ha), its orientation (transversal) besides with its application mode (partial) stimulate the performance of such energy systems. Furthermore, the production of entropy in laminar regime is due only to the thermal irreversibilities, while the produced ones by friction and magnetic field are insignificant. Using the second law of thermodynamics, exergetic efficiency is dominated by heat transfer since the first law of thermodynamics overestimates the pressure drops in the flow.

Automated summary

This study characterizes the efficiency and entropy generation of nanofluid forced convection flow with chaotic perturbations under the influence of a non-uniform magnetic field. The combined effects of chaotic advection, nanoparticles, and non-uniform magnetic field were found to enhance fluid flow performance. The co-effect of magnetic intensity, orientation, and application mode was shown to stimulate energy system performance, with entropy generation mainly attributed to thermal irreversibilities in laminar flow.