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Wärme - und Stoffübertragung

, Volume 17, Issue 2, pp 65–72 | Cite as

Comparison of rectangular and triangular fins when condensation occurs

  • M. Toner
  • A. Kiliç
  • K. Onat
Article

Abstract

In this study rectangular and triangular fins have been compared when condensation occurs. The temperature distributions and the heat transfer found using quasilinearization techniques and those found by using Gauss-Seidel iteration method are compared and this approximation proved to be quite satisfactory. The fin temperature and the fin effectiveness of the triangular and rectangular fins have been determined with and without condensation and optimum fin dimensions have been given as a function of Biot number.

Keywords

Heat Transfer Temperature Distribution Apply Physic Biot Iteration Method 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Nomenclature

b

height of fin

D

diffusion coefficient Eq. (32)

Fx

variable cross-sectional area of fin

F

cross-sectional area at the base of fin

Fp

perimeter of fin

h

average convective heat transfer coefficient

hm

average mass transfer coefficient

k

thermal conductivity of fin material

ka

thermal conductivity of surrounding air Eq. (34)

L

length of fin

m

parameter=(hF p /kF) 1/2

m1

dimensionless parameter=(1+γB/T r )

mw

parameter=m·m k1/2 1

mA

mass flux

P

pressure

Q

heat transfer rate

R

parameter of Eq. (13)

RA

specific gas constant of water vapor

hfg

latent heat

T

temperature of fin

Tref

reference temperature Eq. (15) and Eq. (16)

T0

temperature at the base of fin

T

surrounding temperature

α

thermal diffusivity

η

fin effectiveness

φ

relative humidity

ξ

length parameter=x/L

θ

dimensionless temperature=(T-T)/(T o -t )

Suffixes

A

water vapor

b

base

c

convective

d

dry

L

latent

max

maximum

opt

optimum

r

rectangular

t

triangular

w

wet

Vergleich zwischen rechteckigen und dreieckigen Rippen bei Kondensation

Zusammenfassung

Rechteckige und dreieckige Rippen werden bei Kondensation verglichen. Temperaturverteilung und Wärmeübergang, die mit Hilfe einer Quasilinearisierung gefunden wurden, werden mit jenen nach einer Gauß-Seidel-Iterationsmethode verglichen. Diese Näherung erweist sich als befriedigend. Rippentemperatur und Rippenwirkungsgrad der dreieckigen und der rechteckigen Rippe werden mit und ohne Kondensation bestimmt; optimale Rippenabmessungen werden als Funktion der Biot-Zahl angegeben.

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References

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Copyright information

© Springer-Verlag 1983

Authors and Affiliations

  • M. Toner
    • 1
  • A. Kiliç
    • 1
  • K. Onat
    • 2
  1. 1.Mechanical Engineering FacultyTecnical University of IstanbulMaçka-Beşiktaş-IstanbulTürkei
  2. 2.Mechanical Engineering FacultyTechnical University of IstanbulGümüşsuyu-IstanbulTürkei

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