The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Analysis of Water Condensation and Two-phase Flow in a Channel Relevant for Plate Heat Exchangers

På svenska

Author

Editor

  • Bengt Sundén

Summary, in English

Water vapor condensation and two-phase flow appear in plate heat exchangers being used as condensers. Analysis of water phase change and flow dynamics is an important but complicated task due to large change in water physical/transport properties across the water liquid-vapor interface boundary. In particular, a singular-link behaviour in Navier-Stokes (N-S) equations is present due to the large step change in the density when computational simulation methods are applied. Conventional methods using ensemble averaged parameters such as void fraction are impossible to be applied to cases where high-resolution calculations and detailed analysis are required. In this study, a computational fluid dynamics (CFD) approach is presented for analysis of water vapor condensation and two-phase flow in a channel relevant for plate heat exchanger parallel plates. The developed model is based on the governing equations which are directly solved for the entire single- and two-phase fields. The water phase change and two-phase flow are treated by employing a water liquid-phase fraction factor based on the total enthalpy in each computational cell. The factor is defined as the ratio of the total enthalpy differential to the latent heat of condensation. The density, viscosity and conductivity of the two-phase region are calculated and updated based on the calculated value of the liquid-phase fraction factor until a converged result is reached. It is revealed that, among others, the inlet vapor velocity has significant effects on the water phase change and two-phase flow in the channel, in terms of liquid-water fraction factor distribution.

Department/s

Publishing year

2006

Language

English

Pages

351-360

Publication/Series

Advanced Computational Methods in Heat Transfer IX

Volume

53

Document type

Conference paper

Publisher

WIT Press

Topic

  • Energy Engineering

Status

Published

ISBN/ISSN/Other

  • ISBN: 1-84564-176-0