Entropy generation of nano-fluid inside concentric annuli with rotating outer cylinder

Subject Areas : Heat Transfer

سعید عمادالدین ¹ , احد عابدینی اسفهلانی ²

1 - کارشناس ارشد، گروه مهندسی مکانیک، واحد سمنان، دانشگاه آزاد اسلامی، سمنان، ایران
2 - استادیار، گروه مهندسی مکانیک، واحد سمنان، دانشگاه آزاد اسلامی، سمنان، ایران

Received: 2016-08-14 Accepted : 2016-08-21 Published : 2016-05-21

Keywords: nanoparticles, Entropy Generation, Nano-fluid, concentric annulus, Nusselt number,

Abstract :

In this study entropy generation inside horizontal concentric annulus for Cu Nano-fluid (water) under the constant-temperature conditions has been investigated. The fluid flow inside the cylinder is laminar and the outer cylinder is rotating. The temperature of the outer cylinder is higher and the temperature difference of the two cylinders is always constant. (Result show) Adding nanoparticles to the base fluid at constant boundary conditions has very little effect on the temperature distribution. As the Brinkman number increases, the entropy generation increases where using nanoparticles in the base fluid decreases entropy generation. Friction and heat transfer effects on the total entropy has been studied. It has been shown viscous dissipation is more effective in entropy generation. Extracted results shows that as the Reynolds number increase, the amount of entropy generation increases, and adding nanoparticles lead to the increase of Nusselt number up to 30 percent.