Abstract
This study examines the heat transfer enhancement from a horizontal rectangular fin embedded with triangular perforations (their bases parallel and toward the fin tip) under natural convection. The fin’s heat dissipation rate is compared to that of an equivalent solid one. The parameters considered are geometrical dimensions and thermal properties of the fin and the perforations. The gain in the heat transfer enhancement and the fin weight reduction due to the perforations are considered. The study shows that the heat dissipation from the perforated fin for a certain range of triangular perforation dimensions and spaces between perforations result in improvement in the heat transfer over the equivalent solid fin. The heat transfer enhancement of the perforated fin increases as the fin thermal conductivity and its thickness are increased.
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Abbreviations
- A :
-
cross sectional area of the fin
- A c :
-
cross sectional area of the perforation
- Bi :
-
Biot number
- b :
-
triangular perforation dimension
- h :
-
heat transfer coefficient
- k :
-
thermal conductivity of fin material
- L :
-
fin length
- l :
-
unit vector
- L c :
-
characteristic length
- N :
-
number of perforations
- Ne :
-
total number of finite elements of the perforated fin
- N f :
-
number of finite elements in one of the uniform regions (A or C)
- N n :
-
total number of nodes
- N t :
-
number of finite elements in the tapered region (B)
- Nu :
-
average Nusselt number
- Nu c :
-
average Nusselt number of the inner perforation surface
- OA :
-
open area of the perforated surface
- Q :
-
heat transfer rate
- Ra :
-
Rayleigh number
- Ra c :
-
Rayleigh number of the perforation inner lining surface
- ROA :
-
ratio of the open area
- RQF :
-
ratio of the heat dissipation rate of the perforated fin to that of the non-perforated fin
- RWF :
-
ratio of the perforated fin weight to that of the solid fin (ratio of weight reduction)
- S :
-
perforation spacing
- T :
-
temperature
- t :
-
fin thickness
- W :
-
fin width
- W pf :
-
perforated fin weight
- W sf :
-
solid fin weight
- b:
-
fin base
- l:
-
lower surface of the fin
- max:
-
maximum
- pc:
-
perforation inner surface (within the perforation)
- pf:
-
perforated fin
- ps:
-
perforated surface or the remaining solid portion of the perforated fin
- sf:
-
solid (non-perforated) fin
- ss:
-
solid surface
- t:
-
fin tip
- u:
-
upper surface of fin
- x :
-
longitudinal direction or coordinate
- y :
-
transverse (lateral) direction with the fin width or coordinate
- z :
-
transverse (lateral) direction with the fin thickness or coordinate
- ∞:
-
ambient
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Communicated by LIN Jian-zhong
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AlEssa, A.H., Al-Widyan, M.I. Enhancement of natural convection heat transfer from a fin by triangular perforation of bases parallel and toward its tip. Appl. Math. Mech.-Engl. Ed. 29, 1033–1044 (2008). https://doi.org/10.1007/s10483-008-0807-x
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DOI: https://doi.org/10.1007/s10483-008-0807-x
Key words
- finned surfaces
- heat transfer enhancement
- triangular perforations
- natural convection
- finite element
- perforated fin
- heat dissipation