Global Digital Central Logo Frontiers in Heat and Mass Transfer (FHMT)

Available at www.ThermalFluidsCentral.org
Journal Cover Page

CHARACTERISTICS OF NATURAL CONVECTION FLOW AND HEAT TRANSFER OF PARALLELOGRAMIC ENCLOSURE WITH AN INNER CIRCULAR CYLINDER USING LIQUID NANOFLUIDS

Hasan Sh. Majdi, Ammar Abdulkadhim, Azher M. Abed
Frontiers in Heat and Mass Transfer (FHMT) 12 - 2 (2019)


Abstract


Fluid flow and natural convection heat transfer in a parallelogram enclosure with an inner circular cylinder using Cu-water nanofluid are studied numerically. Dimensionless Navier-Stokes and energy equations are solved numerically using finite element method based two-dimensional flow and steady-state conditions. This study evaluates the effect of different concentrations of Cu-water nanofluids (0% to 6%) with different Rayleigh numbers 103 ≤ Ra ≤ 106 under isotherm wall temperatures. The effects of geometrical parameters of the parallelogram enclosure (inclination angle in range of 0 ≤ α≤ 30  and location of inner circular cylinder -0.2 ≤ H ≤ +0.2 on the flow field and heat transfer are examined. The results are presented in terms of streamlines, isotherms, local and average Nusselt number. It is found that the inclination angle has a significant effect on flow pattern and heat transfer and the inclination angle of 30o at a vertical location H=-0.2 gives better fluid flow strength. Moreover, the maximum heat transfer enhancement is obtained when the circular cylinder moves vertically downward up to H=-0.1 and the inclination angle is 30o. The results also indicate that as the Rayleigh number, nanofluid concentration increase, the rate of heat transfer will increase. 


Full Text: PDF
DOI: http://dx.doi.org/10.5098/hmt.12.2

ISSN: 2151-8629