Abdollah Rezvani | Islamic Azad University, Science and Research Branch (original) (raw)
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Papers by Abdollah Rezvani
Superlattices and Microstructures, 2012
Heat Transfer Engineering, 2014
This article numerically studies entropy generation due to natural convection in a rectangular ca... more This article numerically studies entropy generation due to natural convection in a rectangular cavity with circular corners. In this work, in order to solve the governing equations, an explicit finite-volume procedure and a time-marching method are utilized. Also, instead of the conventional algorithms of SIMPLE, SIMPLEM, and SIMPLEC, an artificial compressibility technique is applied for coupling the continuity to the momentum equations. Entropy generation, as a representation of irreversibility and efficiency loss in engineering heat transfer processes, is analyzed in detail. In this work, effects of the radius of walls corner, Rayleigh number, and distribution ratio on total entropy generation, Nusselt number, and Bejan number are also evaluated. The results show that entropy generation decreases with the increase of the radius of the walls' corner and increases with the increase of Rayleigh number, aspect ratio, and irreversibility ratio.
Laminar slip-¯ow forced convection in rectangular microchannels is studied analytically by applyi... more Laminar slip-¯ow forced convection in rectangular microchannels is studied analytically by applying a modi®ed generalized integral transform technique to solve the energy equation, assuming hydrodynamically fully developed¯ow. Results are given in terms of the¯uid mixed mean temperature, and both local and fully developed mean Nusselt numbers. Heat transfer is found to increase, decrease, or remain unchanged, compared to non-slip-¯ow conditions, depending on two dimensionless variables that include eects of rarefaction and the¯uid/wall interaction. The transition point at which the switch from heat transfer enhancement to reduction occurs is identi®ed for dierent aspect ratios. Ó : S 0 0 1 7 -9 3 1 0 ( 0 1 ) 0 0 0 7 5 -8
Superlattices and Microstructures, 2012
Heat Transfer Engineering, 2014
This article numerically studies entropy generation due to natural convection in a rectangular ca... more This article numerically studies entropy generation due to natural convection in a rectangular cavity with circular corners. In this work, in order to solve the governing equations, an explicit finite-volume procedure and a time-marching method are utilized. Also, instead of the conventional algorithms of SIMPLE, SIMPLEM, and SIMPLEC, an artificial compressibility technique is applied for coupling the continuity to the momentum equations. Entropy generation, as a representation of irreversibility and efficiency loss in engineering heat transfer processes, is analyzed in detail. In this work, effects of the radius of walls corner, Rayleigh number, and distribution ratio on total entropy generation, Nusselt number, and Bejan number are also evaluated. The results show that entropy generation decreases with the increase of the radius of the walls' corner and increases with the increase of Rayleigh number, aspect ratio, and irreversibility ratio.
Laminar slip-¯ow forced convection in rectangular microchannels is studied analytically by applyi... more Laminar slip-¯ow forced convection in rectangular microchannels is studied analytically by applying a modi®ed generalized integral transform technique to solve the energy equation, assuming hydrodynamically fully developed¯ow. Results are given in terms of the¯uid mixed mean temperature, and both local and fully developed mean Nusselt numbers. Heat transfer is found to increase, decrease, or remain unchanged, compared to non-slip-¯ow conditions, depending on two dimensionless variables that include eects of rarefaction and the¯uid/wall interaction. The transition point at which the switch from heat transfer enhancement to reduction occurs is identi®ed for dierent aspect ratios. Ó : S 0 0 1 7 -9 3 1 0 ( 0 1 ) 0 0 0 7 5 -8