|dc.identifier.citation||Fang, C-C. 1949. The mechanism of dropwise condensation of steam. Queen Mary University of London||en_US
|dc.description.abstract||The present investigation can be divided into two
parts: (a) experiments made to examine the mechanism of
dropwise condensation of steam with particular reference
to the stability of drop promoting surfaces as affected
by the material of cooled surface, the drop promoter, the
surface finish, the rate of heat transmission, and the
presence of non-condensable gas. and (b) a theoretical
analysis of the beat transmission through individual
droplets, the transient heat transfer through exposed
areas, the statistical study of drop size distribution,
and the estimation of steam side coefficient.
An apparatus was developed to examine qualitatively,the
behaviour of drop promoting surfaces on a small scale.
It is considered that sufficient evidence was found to
show that steam in contact with a cooled surtace condenses
as a thin liquid film which later breaks into droplets.
surfaces treated to give dropwise condensation deteriorate
into mixed condensation in due time, and the duration tor
which a treated surface maintains dropwise condensation
varies between a few hours to several days, depending on
many factors among which· the presence of non-condensable gas
must not be overlooked.
An approximation to the heat transmission through
individual droplets has been worked out with assumed heat
flow lines. The result, checked by the relaxation method.
is correct within . + 10%. An analysis Of the transient
heat transfer through exposed areas was made neglecting the
increasing resistance of any accumulating liquid. The
drop size distribution was analyzed tor one drop promoting
surface at three different heat transmission rates. Based
on this drop size distribution, the heat transmission through
the drops was estimated by assuming they were held at rest on
a cooled surface conducting heat under a steady state. . The
estimated coefficient comes within the range or experimental
results of many investigators.||en_US
|dc.description.sponsorship||Department or Scientific end Industrial Research||en_US
|dc.publisher||Queen Mary University of London||en_US
|dc.rights||The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the author||
|dc.title||The mechanism of dropwise condensation of steam||en_US