Wärme - und Stoffübertragung

, Volume 13, Issue 1–2, pp 137–143 | Cite as

Axiale Diffusion in Dampfkondensatoren bei Inertgasbelastung

  • P. G. Kosky
  • H. Jaster
Article
  • 37 Downloads

Zusammenfassung

In einer Modell rechnung wird die Höhe der Mischzone zwischen Gas und Dampf in einem Kondensator bestimmt. Die mitgeteilte Gleichung ist algebraisch einfach und enthält den dimensionslosen Ausdruck zi*, der auch zahlreiche verwandte Probleme charakterisieren sollte:
$$z_i^* = z_i \sqrt {\frac{{4U\Delta T_0 \tilde RT_0 }}{{pD_0 R\tilde h_{fg} }}} .$$
Mitgeteilte Daten bestätigen das mathematische Modell.

Nomenclature

c

Gas phase concentration

D

Binary mass diffusion coefficient

h

Molar enthalpy

hfg

Molar latent heat of vaporization

k

Thermal conductivity

L

Characteristic length

N

Molar flux

p

Total pressure

pv

Vapor pressure

q″

Surface heat flux

R

Tube radius

R

Universal gas constant

T

Absolute temperature

T

Ambient temperature

t

Wall thickness

U

Overall heat transfer coefficient

y

Vapor mole fraction

z

Axial coordinate

z*

Non-dimensional axial coordinate (z-zo)/l

Greek

δ

Non-dimensional temperature approach

ΔT0

Overall temperature difference

Π0

Vapor pressure constant

Φ

Non-dimensional temperature (T-T)/ΔT0

Subscripts

G

Pertaining to gas

i

Pertaining to upper extremity of interfacial zone

L

Pertaining to liquid

V

Pertaining to vapor

0

Pertaining to lower extremity of interfacial zone

Axial diffusion in gas blanketed vapor condensers

Abstract

A model is given, which permits determination of the height of a zone of mixing between a gas and a vapor in a condenser. The resulting predictive equation is algebraically simple and contains a non-dimensional group, zi*, which should characterize a host of related problems:
$$z_i^* = z_i \sqrt {\frac{{4U\Delta T_0 \tilde RT_0 }}{{pD_0 R\tilde h_{fg} }}} .$$
Data are presented which verify the mathematical model.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Edwards, D.K.; Marcus, B.D.: Heat and Mass Transfer in the Vicinity of the Vapor-Gas Front in a Gas-Loaded Heat Pipe. J. Ht. Transfer. Trans. ASME,94C. 155 (1972)Google Scholar
  2. 2.
    Kosky, P.G.; Jaster, H.: Coupled dielectric and thermodynamic considerations for the design of vaporization cooled electrical systems. J. Electrostatics,6, 109 (1979)Google Scholar
  3. 3.
    Catchpole, J.P.; Pulford, G.: Dimensionless Groups, Handbook of Chemistry and Physics, (CRC Press), 57th, Edn. (1976–1977) p. F. 326Google Scholar
  4. 4.
    Huynh, D.T.: Unsteady Condensation in parallel condenser tubes containing non-condensable gas. M.S. Thesis, Lehigh University (1977)Google Scholar
  5. 5.
    Glasstone, S.: Textbook of Physical Chemistry. McMillan and Sons, London, 2nd Edn (1956) p. 457Google Scholar

Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • P. G. Kosky
    • 1
  • H. Jaster
    • 1
  1. 1.General Electric Research and Development CenterSchenectadyUSA

Personalised recommendations