Characterisation and modelling of flow mechanisms for direct contact condensation of steam injected into water
Abstract
Direct contact condensation of steam injected into water is a special mode
of condensation where condensation occurs on the interface between steam
and water. This type of condensation forms an essential part of various
industrial applications and correct prediction and modelling of the condensation
behaviour is crucial to obtain an optimised design of such devices.
While present prediction models for direct contact condensation are valid
for a limited range of flow conditions only, the work presented in this thesis
provides improved models for direct contact condensation. The models
are developed in the form of diagrams and include: a condensation regime
diagram, for predicting the condensation behaviour, a steam plume length
diagram, for predicting the penetration distance of steam into water, and a
heat transfer coefficient diagram.
These models are derived using a wide range of data and therefore provide
more accurate predictions compared with alternative models available
in literature. In contrast to present models, the derived models presented in
this work are constructed using an additional physical parameter to describe
the process.
The diagrams are validated against independent experiments and demonstrate
close agreement. Furthermore, the predictions from the condensation
regime diagram and steam plume length diagram are self-consistent.
The models developed in this study are capable of predicting condensation
behaviour for a wide range of initial conditions and can be used in
conjunction with computational fluid dynamics techniques for direct contact
condensation.
Publication date
2006Published version
https://doi.org/10.18745/th.14345https://doi.org/10.18745/th.14345