Numerical simulation of Cu-water nanofluid magneto-hydro-dynamics and heat transfer in a cavity containing a circular cylinder of different size and positions

Abstract

In the present study, a nanofluid filled cavity with sinusoidal temperature boundary condition, under the influence of an inclined magnetic field is investigated numerically. The LBM method is applied to simulate the Cu-Water nanofluid flow around an average temperature circular cylinder. In this study, the different braking manners of the magnetic field and the obstacle are compared for different field intensities and directions and various obstacle sizes and positions. The flow and heat transfer behavior of the nanofluid were observed for different Rayleigh numbers (103-106), Hartmann numbers (0-90), nanoparticles' volume fraction (0-6 %), magnetic field direction = (0-90o) and obstacle aspect ratios (0.05, 0.1 and 0.2) and positions (0-8). The results indicated that the influence of nanoparticles for this geometry and boundary condition is highly dependent on the Rayleigh and Hartmann numbers. Also, it was shown that for lower Ra numbers, the obstacle with an aspect ratio of 0.1 presents better heat transfer rate; while for higher Ra numbers the obstacle size is much less important than its position.

A numerical investigation of natural convection heat transfer of copper-water nanofluids in a rectotrapezoidal enclosure heated uniformly from the bottom wall

“…• Consideration of lesser Rayleigh number Ra=10 4 , resulted in formation of weak anti-clockwise flow strength and dome shaped isothermal contour in the rectotrapezoidal cavity. Circulation strength of streamlines as observed increase with higher Rayleigh number and and are also found to be increasing in strength with higher volume fraction.…”

“…The subject, heat transfer and fluid flow in the presence of natural convection with or without the presence of nanofluid in different enclosures like square [1][2][3], enclosure with conducting solid square cylinder at center [4], rectangular [5], trapezoidal [6], quadrantal [7][8] has been extensively analysed in the last few decades using experimental and numerical procedure, as because it has been of considerable interest and has wide spread applications in many engineering applications, such as heat exchangers, energy efficient window designing, air conditioning of domestic and commercial buildings, crystal growth, solar water heaters and coolers, printed circuit board cooling, ocean engineering circulation etc. In this context, it goes without saying that when natural convection heat transfer is the primary source of heat transfer in complex enclosures, such systems needs to deeply understood for its thermal efficiency and other heat transfer parameters for bringing in more savings.…”

Mathematical Modelling of MHD Natural Convection in a Linearly Heated Porous Cavity

“…The above study is conducted to explain the fluid flow and heat transfer that occurs due to natural convection. Ahrara et al [10] simulated the flow that occurs in the Cu-water nanofluid from the combinations of natural convection, magnetic fields and its inclination effects on a cavity with a circular cylinder inside. Mahmoodi et al [11] presented a work to demonstrate the water-Al2O3 nanofluid flow behavior on the square cavity by different combinations of linearly cooled/heated-left/right walls due to natural convection.…”

Heat transfer characteristics of MWCNT nanofluid in rectangular mini channels

“…The obtained nanofluid is passed through the minichannels which results in great enhancement of heat transfer rate [19][20]. Many nanofluids prepared using nanoparticles like Al2O3, CuO, TiO2, SiO2, MWCNT etc., are studied by various researchers for their application in different heat sinks and heat exchangers [7,21,22], [23][24][25], [26]. The other type of heat sink is microchannel, but there is large pressure drop compared to minichannels which leads to high pumping power requirement.…”