Salam Hadi Hussain

Mixed Convection Heat Transfer of Air inside a Square Vented Cavity with a Heated Horizontal Square Cylinder

The study of two-dimensional mixed convection from a heated square solid cylinder located at the center of a vented cavity filled with air (Pr = 0.71) is performed. The horizontal walls and the right vertical wall are kept adiabatic, while the left vertical wall is maintained at a constant temperature T c . The flow is assumed to be laminar, steady and of constant physical properties except for the density in the buoyancy term, which follows the Boussinesq approximation. The developed mathematical model is governed by the coupled equations of continuity, momentum, and energy and is solved by the finite-difference method. This study investigates the effects of the outlet positions, Richardson numbers, Reynolds numbers, locations, and aspect ratios of inner square cylinder on the flow and the thermal fields. The parameters studied and their ranges are as follows: the Richardson number and Reynolds number are varied in the ranges from 0–10 and 50–200, respectively, location of the inner cylinder (0.25 ≤ L X ≤ 0.75, 0.5 ≤ L Y ≤ 0.75), and aspect ratios of 0.1, 0.2, 0.3, and 0.4. The present results show that the average Nusselt number along the heated surface of the inner square values increases with increasing values of the Reynolds and Richardson numbers. The effect of the locations of the inner square cylinder and aspect ratio is found to play a significant role in the streamline and isotherm patterns. An empirical correlation is developed by using the Nusselt number and the Reynolds and Richardson numbers. The results are compared and verified with previously published results, and good agreement is achieved.

Conduction-combined forced and natural convection in a lid-driven parallelogram-shaped enclosure divided by a solid partition

Conduction-combined forced and natural convection heat transfer flow of air in a differentially heated lid-driven parallelogram-shaped enclosure divided by a solid partition has been formulated and solved numerically using the finite-volume method with the SIMPLE algorithm. For the two-dimensional problem, numerical solutions are obtained for a wide range of Richardson numbers (0.1 ≤Ri ≤ 10), inclination angles of enclosure from the vertical direction (-60° ≤Φ≤ 60°), and thermal conductivity ratios (0.001 ≤K ≤ 10). The results indicate that all of the studied parameters and direction of moving lid have significant effects on Nusselt number and the average skin friction coefficient.

Numerical analysis of steady natural convection of water in inclined square enclosure with internal heat generation

Laminar natural convection in a two-dimensional inclined square enclosure has been numerically studied using finite volume method. The research deals with the investigation of the effect of Prandtl number and inclination angle on the stream contours and isotherms in this enclosure where the left side wall is maintained at isothermal hot temperature, while the opposite side wall is maintained at isothermal cold temperature. The other top and bottom walls are considered thermally insulated. The enclosure in the present work is based on the geometry of Tofiqul Islam et al. [9], (2007) which is considered inclined with inclination angles ranging from 0° to 30° and filled with water as a working fluid where its Prandtl number is taken as 6. All the numerical calculations are performed at the external Rayleigh numbers 103 and 106 while the internal Rayleigh numbers ranging from 105 to 108. The results are presented as a streamline and isotherm plots as well as the variation of the average Nusselt numbers at the hot wall are also presented. The results show a good confidence with other published results.

Inclination angle effect on natural convection in a square cavity partially filled with non-Newtonian fluids layer

The problem of inclination angle effect on natural convection in a square cavity partially filled with non-Newtonian fluid layer is studied numerically using The Finite Volume Method. Governing equations are solved over wide range of Darcy number (10−5 ≤ Da ≤ 10−1), power-law index(0.6 ≤ n ≤ 1.4), the inclination angle of the cavity (0° ≤ ω ≤ 90°), Rayleigh number (Ra = 105) and porous layer thickness (S = 0.5). The results presented for values of the governing parameters in terms of streamlines in both porous/non-Newtonian fluid-layer, isotherms in both porous/non-Newtonian fluid-layer and average Nusselt number. It is shown that the heat transfer has maximum value when the power-law index is less than one (pseudoplastic fluid), and then decreases remarkably as the power-law index increases. The results have possible applications in heat-removal and heat-storage non-Newtonian fluid-saturated porous systems.

Numerical study of natural convection heat transfer of air flow inside a corrugated enclosure in the presence of an inclined heated plate

A steady laminar natural convection of air flow in a sinusoidal corrugated enclosure containing a tilted hot thin plate located symmetrically at its centreline is numerically studied. The enclosure horizontal walls are adiabatic, while the vertical walls are sinusoidal corrugated with corrugation frequencies varied from 1 to 3 and kept at cold temperature. Finite volume was used to solve governing equations. Calculations have been made for Rayleigh numbers ranging from 103 to 106 and Prandtl number was taken to be 0.71. The average Nusselt number is found to increase as Rayleigh number increases and it slightly increases with corrugation frequency.