Second Law Investigation in a Non-Newtonian Liquid Flow in a Porous Channel with Circular Obstacle

The problem of non-Newtonian fluid flow has taken considerable interest and has been the subject of several work in latest years due to its various requests in different fields of engineering, in particular the interest in the problems of heat transfer in non-Newtonian liquids, such as lubrication, hot rolling, cooling problem and drag reduction. Here, mixed convection heat transport and its related entropy production in a porous channel with circular obstacle saturated via non-Newtonian power law liquid has been scrutinized. The influences on entropy production of the power law index, the Reynolds number, the Rayleigh number and the Darcy number are investigated. Being a noveltyIP: ofthis203.8.109.20work, anOn: Wed,optimization 02 Aug study2023of the10:03:16thermodynamic irreversibility as a function of the channel inclination angle and the power law index is undertaken. The governing equations of the problem are solved employing the COMSOL software. Outcomes illustrate that the governing parameters Delivered by Ingenta strongly affect the entropy production. The thermal entropy generation is maximal at low value of power law index and high value of Reynolds number. The effect of Reynolds number become insignificant at relatively high power law index. At fixed Reynolds number value, a rise in the power index (n) leads to a reduce in the thermal entropy. This decrease is tiny, at low value of Reynolds number (Re) and turn into increasingly considerable as Re rises. The streamlines show the existence of two recirculation zones just after the circular obstacle, whose existence depends on both Re and power law index. Results show that the greatest variation relating to the inclination angle is for power law index equal to 0.4. Results indicate also that, at low Darcy number and relatively high power law index, the intrinsic effect of the modified Darcy number on Darcy viscous irreversibility become pronounced giving a sharp increase in the total entropy production.

Automated summary

This study examines the heat transport and entropy production of non-Newtonian fluid flow, and investigates the influence of various factors on entropy production. By solving the governing equations using COMSOL software, it is found that the parameters have a significant impact on entropy production. Thermal entropy generation is maximized at low power law index and high Reynolds number, while the effect of Reynolds number becomes insignificant at relatively high power law index.