Numerical investigation of natural convection in a square enclosure partially filled with horizontal layers of a porous medium

Abdulwahed A.S. Abdulwahed; Luma F. Ali Ali

doi:10.1002/htj.22720

Details

Publication Date

Wed Oct 05 2022

Journal Name

Heat Transfer

Volume

52

DOI

10.1002/htj.22720

Choose Citation Style

Statistics

View publication

31

Statistics

(9)

(8)

Numerical investigation of natural convection in a square enclosure partially filled with horizontal layers of a porous medium

Abdulwahed A.S. Abdulwahed

Luma F. Ali Ali

...Show More Authors

AbstractTwo‐dimensional buoyancy‐induced flow and heat transfer inside a square enclosure partially occupied by copper metallic foam subjected to a symmetric side cooling and constant heat flux bottom heating was tested numerically. Finite Element Method was employed to solve the governing partial differential equations of the flow field and the Local Thermal Equilibrium model was used for the energy equation. The system boundaries were defined as lower heated wall by constant heat flux, cooled lateral walls, and insulated top wall. The three parameters elected to conduct the study are heater length (7 ≤ <italic>ζ</italic> ≤ 20 cm), constant heat flux (150 ≤ <italic>q</italic>″ ≤ 600 W m−2), and porous material thickness (5 ≤ <italic>H</italic> ≤ 20 cm). The porous material used was the copper metal foam of porosity = 0.9 and pore density PPI = 10, and saturated with a fluid of Prandtl number = 0.7. On the basis of the results obtained, it was concluded that at the porous layer thickness = 5 cm, the rate of heat transferred was (74.6%) higher than when the layer height was 20 cm (the cavity is fully filled) and at the same thickness it was found that the heat rate is (51.4%) higher than when using the half filling (<italic>H</italic> = 10 cm). Further, the local and mean Nusselt number is maximum when using the largest heater size and smallest porous layer thickness. Finally, better circulation and convective modes were observed at high values of heat flux.

View Publication

Publication Date

Thu Jan 01 2026

Journal Name

Chalcogenide Letters

Structural and Optical Properties of Cu2ZnSn(S1−xSex)4 Nanostructures Thin Film for Photovoltaic Applications

Cu2 ZnSn(S1−x Se x)4 thin film

energy gap

dielectric constant

extinction coefficient

refractive index

Bushra A.

Ameer J.

Ahmad A.

Yasser A.

...Show More Authors

Copper zinc tin sulfide selenide, Cu2 ZnSn(S1−x Se x)4 , absorbers are promising earth-abundant and environmentally benign materials for low-cost photovoltaic applications. This study investigates the structural and optical properties of Cu 2 ZnSn(S1−x Se x)4 nanostructured thin films prepared by pulsed laser deposition using melt-quenched targets with selenium compositions x = 0.0–1.0. X-ray diffraction revealed that films with low selenium content remained amorphous, whereas higher selenium incorporation promoted the formation of polycrystalline kesterite–stannite phases with preferred orientations along (112), (200), (220), and (312). The crystallite size increased from 12.3 to 17.9 nm as selenium reached x = 1.0, indicating enha

View Publication

(1)

Publication Date

Tue Jan 18 2022

Journal Name

Materials Science Forum

The Effect of Gamma Radiation on the Manufactured HgBa2Ca2Cu2.4Ag0.6O8+δ Compound

Gamma doses radiation

crystal size

strain

degree of crystallinity

Scherrer

crystallinity and Williamson equations.

zainab j

Balqees A.

Mohammed A.

Kareem A.

Auday H.

...Show More Authors

In this article four samples of HgBa₂Ca₂Cu_2.4Ag_0.6O_8+δ were prepared and irradiated with different doses of gamma radiation 6, 8 and 10 Mrad. The effects of gamma irradiation on structure of HgBa₂Ca₂Cu_2.4Ag_0.6O_8+δ samples were characterized using X-ray diffraction. It was concluded that there effect on structure by gamma irradiation. Scherrer, crystallization, and Williamson equations were applied based on the X-ray diffraction diagram and for all gamma doses, to calculate crystal size, strain, and degree of crystallinity. I

View Publication

(7)

1 2 3 4 ... 3009 3010 3011 3012