RETRACTED: Laminar single‐phase and two‐phase modeling of water/MgO nanofluid flow inside a rectangular microchannel with rhombic vortex generators

Abstract

AbstractIn the present numerical simulation, laminar single‐phase and two‐phase nanofluid flows are investigated inside a rectangular microchannel with the vortex generators. Rhombic vortex generators with different attack angles are used for a better mixture of fluid. Water/MgO nanofluid is used as the working fluid in the volume fractions of nanoparticles φ = 0‐4% in Reynolds numbers of Re = 1‐300 at the two‐dimensional space. The presence of vortex generators with attack angles of λ = 0‐45°, and simultaneous investigation of heat transfer and flow hydrodynamic parameters distinguish this research from other similar studies. Obtained results revealed that using nanofluid with higher volume fractions, slip boundary condition on the hot wall, and using vortex generator with higher λ lead to significant enhancement of heat transfer. Also, the value of pressure drop augmentation is caused by the increase of φ and λ is significant at higher Reynolds numbers. Unlike the increase of φ, by increasing Reynolds number, the effect of slip boundary condition becomes considerable on the reduction of entropy generation. The behavior of entropy generation graphs with slip velocity boundary condition on the wall is different from the no‐slip boundary condition at Re = 300. The behavior of average entropy generation is different in the various φ, Reynolds numbers, and λ in the no‐slip boundary condition for single‐phase and two‐phase models. Also, the two‐phase model estimates flow behavior with less irreversibility.