ISSN Online: 2377-424X
ISBN Print: 0-89116-299-2
International Heat Transfer Conference 7
CONDENSATION INSIDE A VERTICAL TUBE
Abstrakt
Experimental data for local heat transfer
coefficients for the condensation of freon-113
inside a vertical tube are presented. The data is
for two inlet vapour Reynolds Numbers, 50 300 and
141 100. The freon is saturated at the entrance
to the condenser and a uniform annular condensate
film grows along the tube. Models for laminar and
turbulent flow of the condensate film are presented
the latter using the Von Karman analysis but with
the dimensionless thickness of the laminar sub-layer
as a variable. This permits an analysis which allows
different amounts of turbulent mixing to be included.
The experimental results strongly support
the laminar flow model for the major part of the
process. However, it is concluded that some
turbulent mixing occurs at the lower part of the
condenser and that a dimensionless film thickness
of 12.5 is required prior to the appearance of
turbulence in the condensate film.