Laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows
Laminar mixed convection heat transfer for assisted and opposed air flows in the entrance region of a vertical circular tube with the using of a uniform wall heat flux boundary condition has been experimentally investigated. The experimental setup was designed for determining the effect of flow dire...
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my.uniten.dspace-309572023-12-29T15:56:35Z Laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows Mohammed H.A. 15837504600 Buoyancy opposed flow Buoyancy-assisted flow Empirical correlations Mixed convection Vertical circular tube Boundary conditions Buoyancy Correlation methods Heat transfer Mixed convection Reynolds number Buoyancy opposed flows Buoyancy-assisted flows Empirical correlations Vertical circular tubes Pipe flow Laminar mixed convection heat transfer for assisted and opposed air flows in the entrance region of a vertical circular tube with the using of a uniform wall heat flux boundary condition has been experimentally investigated. The experimental setup was designed for determining the effect of flow direction and the effect of tube inclination on the surface temperature, local and average Nusselt numbers with Reynolds number ranged from 400 to 1600 and Grashof number from 2.0 � 105 to 6.2 � 106. It was found that the circumferential surface temperature along the dimensionless tube length for opposed flow would be higher than that both of assisted flow and horizontal tube [Mohammed HA, Salman YK. Experimental investigation of combined convection heat transfer for thermally developing flow in a horizontal circular cylinder. Appl Therm Eng 2007;27(8-9):1522-33] due to the stronger free convective currents within the cross-section. The Nusselt number values would be lower for opposed flow than that for assisted flow. It was inferred that the behaviour of Nux for opposed flow to be strongly dependent on the combination of Re and Gr numbers. Empirical equations expressing the average Nusselt numbers in terms of Grashof and Reynolds numbers were proposed for both assisted and opposed flow cases. The average heat transfer results were compared with previous literature and showed similar trend and satisfactory agreement. � 2008 Elsevier Ltd. All rights reserved. Final 2023-12-29T07:56:35Z 2023-12-29T07:56:35Z 2008 Article 10.1016/j.enconman.2008.02.009 2-s2.0-44249112064 https://www.scopus.com/inward/record.uri?eid=2-s2.0-44249112064&doi=10.1016%2fj.enconman.2008.02.009&partnerID=40&md5=ae4fa045bfde9cee01e86947e8a77950 https://irepository.uniten.edu.my/handle/123456789/30957 49 8 2006 2015 Scopus |
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Buoyancy opposed flow Buoyancy-assisted flow Empirical correlations Mixed convection Vertical circular tube Boundary conditions Buoyancy Correlation methods Heat transfer Mixed convection Reynolds number Buoyancy opposed flows Buoyancy-assisted flows Empirical correlations Vertical circular tubes Pipe flow |
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Buoyancy opposed flow Buoyancy-assisted flow Empirical correlations Mixed convection Vertical circular tube Boundary conditions Buoyancy Correlation methods Heat transfer Mixed convection Reynolds number Buoyancy opposed flows Buoyancy-assisted flows Empirical correlations Vertical circular tubes Pipe flow Mohammed H.A. Laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows |
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Laminar mixed convection heat transfer for assisted and opposed air flows in the entrance region of a vertical circular tube with the using of a uniform wall heat flux boundary condition has been experimentally investigated. The experimental setup was designed for determining the effect of flow direction and the effect of tube inclination on the surface temperature, local and average Nusselt numbers with Reynolds number ranged from 400 to 1600 and Grashof number from 2.0 � 105 to 6.2 � 106. It was found that the circumferential surface temperature along the dimensionless tube length for opposed flow would be higher than that both of assisted flow and horizontal tube [Mohammed HA, Salman YK. Experimental investigation of combined convection heat transfer for thermally developing flow in a horizontal circular cylinder. Appl Therm Eng 2007;27(8-9):1522-33] due to the stronger free convective currents within the cross-section. The Nusselt number values would be lower for opposed flow than that for assisted flow. It was inferred that the behaviour of Nux for opposed flow to be strongly dependent on the combination of Re and Gr numbers. Empirical equations expressing the average Nusselt numbers in terms of Grashof and Reynolds numbers were proposed for both assisted and opposed flow cases. The average heat transfer results were compared with previous literature and showed similar trend and satisfactory agreement. � 2008 Elsevier Ltd. All rights reserved. |
| author2 |
15837504600 |
| author_facet |
15837504600 Mohammed H.A. |
| format |
Article |
| author |
Mohammed H.A. |
| author_sort |
Mohammed H.A. |
| title |
Laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows |
| title_short |
Laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows |
| title_full |
Laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows |
| title_fullStr |
Laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows |
| title_full_unstemmed |
Laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows |
| title_sort |
laminar mixed convection heat transfer in a vertical circular tube under buoyancy-assisted and opposed flows |
| publishDate |
2023 |
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1806427704338153472 |
| score |
13.222552 |