Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins
Natural convection in an annular space provided with metal foam fins attached to the inner cylinder is studied numerically. The metal foam fins made of copper were inserted in different axial sections with three fins in each section. The temperature of the inner cylinder is kept constant while...
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| Format: | Article |
| Language: | English |
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University of Baghdad
2022-04-01
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| Series: | Journal of Engineering |
| Subjects: | |
| Online Access: | https://joe.uobaghdad.edu.iq/index.php/main/article/view/1531 |
| _version_ | 1827836509654351872 |
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| author | Israa H. Alkinani Luma Fadhil Ali |
| author_facet | Israa H. Alkinani Luma Fadhil Ali |
| author_sort | Israa H. Alkinani |
| collection | DOAJ |
| description |
Natural convection in an annular space provided with metal foam fins attached to the inner cylinder is studied numerically. The metal foam fins made of copper were inserted in different axial sections with three fins in each section. The temperature of the inner cylinder is kept constant while the annular outer surface is adiabatic. The thickness effect of the inner pipe wall was considered. Naiver Stokes equation with Boussinesq approximation is used for the fluid regime while Brinkman-Forchheimer Darcy model is used for metal foam. In addition, the local thermal non-equilibrium condition in the energy equation of the porous media is presumed. The effect of Rayleigh number and number of foam fins in the axial direction, on fluid flow and heat transfer characteristics, were examined. The current model was valid with the available published results and good agreement is noticed. Results showed that as the Rayleigh number increases the dominated of convection mode increases and average Nusselt increases. It was found that at Rayleigh of 106 Nusselt reached its higher value which is 4.6 for the case of adding seven axial metal foams. A comparison between adding foam fins and copper fins was established for a range of Rayleigh numbers between 104 and 106. It showed a good enhancement in Nusselt number and the greatest enhancement percentage was 45.9% at Rayleigh equal 106 for the case of using seven sections of foam fins.
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| first_indexed | 2024-03-12T06:28:48Z |
| format | Article |
| id | doaj.art-36f2d92961ed4e8693f2c881f222b850 |
| institution | Directory Open Access Journal |
| issn | 1726-4073 2520-3339 |
| language | English |
| last_indexed | 2024-03-12T06:28:48Z |
| publishDate | 2022-04-01 |
| publisher | University of Baghdad |
| record_format | Article |
| series | Journal of Engineering |
| spelling | doaj.art-36f2d92961ed4e8693f2c881f222b8502023-09-03T01:45:50ZengUniversity of BaghdadJournal of Engineering1726-40732520-33392022-04-0128410.31026/j.eng.2022.04.01 Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam finsIsraa H. Alkinani0Luma Fadhil Ali 1College of Engineering - University of BaghdadCollege of Engineering - University of Baghdad Natural convection in an annular space provided with metal foam fins attached to the inner cylinder is studied numerically. The metal foam fins made of copper were inserted in different axial sections with three fins in each section. The temperature of the inner cylinder is kept constant while the annular outer surface is adiabatic. The thickness effect of the inner pipe wall was considered. Naiver Stokes equation with Boussinesq approximation is used for the fluid regime while Brinkman-Forchheimer Darcy model is used for metal foam. In addition, the local thermal non-equilibrium condition in the energy equation of the porous media is presumed. The effect of Rayleigh number and number of foam fins in the axial direction, on fluid flow and heat transfer characteristics, were examined. The current model was valid with the available published results and good agreement is noticed. Results showed that as the Rayleigh number increases the dominated of convection mode increases and average Nusselt increases. It was found that at Rayleigh of 106 Nusselt reached its higher value which is 4.6 for the case of adding seven axial metal foams. A comparison between adding foam fins and copper fins was established for a range of Rayleigh numbers between 104 and 106. It showed a good enhancement in Nusselt number and the greatest enhancement percentage was 45.9% at Rayleigh equal 106 for the case of using seven sections of foam fins. https://joe.uobaghdad.edu.iq/index.php/main/article/view/1531Natural Convection, Metal Foam, Concentric Cylinders, Local Thermal Non Equilibrium, Numerical Investigation. |
| spellingShingle | Israa H. Alkinani Luma Fadhil Ali Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins Journal of Engineering Natural Convection, Metal Foam, Concentric Cylinders, Local Thermal Non Equilibrium, Numerical Investigation. |
| title | Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins |
| title_full | Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins |
| title_fullStr | Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins |
| title_full_unstemmed | Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins |
| title_short | Numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins |
| title_sort | numerical study of natural convection in an annulus between two concentric cylinders provided with metal foam fins |
| topic | Natural Convection, Metal Foam, Concentric Cylinders, Local Thermal Non Equilibrium, Numerical Investigation. |
| url | https://joe.uobaghdad.edu.iq/index.php/main/article/view/1531 |
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