Reducing Entropy Generation in MHD Fluid Flow over Open Parallel Microchannels Embedded in a Micropatterned Permeable Surface

Abstract

Abstract:The present study examines embedded open parallel microchannels within a micropatterned permeable surface for reducing entropy generation in MHD fluid flow in microscale systems. A local similarity solution for the transformed governing equations is obtained. The governing partial differential equations along with the boundary conditions are first cast into a dimensionless form and then the reduced ordinary differential equations are solved numerically via the Dormand-Prince pair and shooting method. The dimensionless entropy generation number is formulated by an integral of the local rate of entropy generation along the width of the surface based on an equal number of microchannels and no-slip gaps interspersed between those microchannels. Finally, the entropy generation numbers, as well as the Bejan number, are investigated. It is seen that surface-embedded microchannels can successfully reduce entropy generation in the presence of an applied magnetic field.

Entropy Generation Analysis of Power-Law Non-Newtonian Fluid Flow Caused by Micropatterned Moving Surface

“…Later, a study based on liquid flow over open microchannels was investigated by Yazdi et al [6]. In another study, they [8] presented the second law analysis of MHD flow over embedded microchannels in an impermeable surface. Later, Yazdi et al [7] investigated entropy generation analysis of electrically conducting fluid flow over open parallel microchannels embedded within a continuous moving surface in the presence of applied magnetic field where the free stream velocity was stationary and the fluid was moving by an external surface force.…”

“…Later, Yazdi et al [7] investigated entropy generation analysis of electrically conducting fluid flow over open parallel microchannels embedded within a continuous moving surface in the presence of applied magnetic field where the free stream velocity was stationary and the fluid was moving by an external surface force. Recently, they [41] have evaluated the reduction of entropy generation by embedded open parallel microchannels within the permeable surface in order to reach a liquid transportation design in microscale MHD systems. A Newtonian fluid has been considered in previous EBSM researches.…”

“…Before considering entropy generation analysis, the flow and heat transfer part should be evaluated first. As explained, non-Newtonian fluid flow has received considerable attention due to many important applications in both micro- [1][2][3][4][5][6][7][8] and macroscale technologies [9]. Examples of non-Newtonian fluids include grease, cosmetic products, blood, body fluids, and many others [10].…”

Effect of Magnetic Field on Entropy Generation in a Microchannel Heat Sink with Offset Fan Shaped

“…They founded that the magnetic field decreases the convection currents, the heat transfer and entropy generation inside the enclosure. Yazdi et al [18,19] investigated the entropy generation numbers, as well as the Bejan number in Mgneto Hydro Dinamics (MHD) fluid flow in open parallel microchannels. They showed that entropy generation reduces in the presence of magnetic field.…”

“…Many studies have been done for entropy generation analysis by various boundary conditions [17][18][19]. Nevertheless, to the best of our knowledge, there has not yet been any investigation made into the effects of uniform and non-uniform transverse magnetic fields on entropy generation on ferrofluid in a microchannel.…”