An experimental study of the thermohydraulic characteristics of flow boiling in horizontal pipes: Linking spatiotemporally resolved and integral measurements
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
Data are presented from experiments of flow boiling in a horizontal pipe. Specifically, refrigerant R245fa was evaporated in a 12.6 mm stainless steel pipe to which a uniform heat flux of up to 38 kW/m was applied. The bespoke facility operated at mass fluxes in the range 30–700 kg/m s and a saturation pressure of 1.7 bar. Flow patterns were identified through high-speed imaging and the resulting flow pattern map is compared to existing maps in the literature. Predictive methods for the pressure drop and heat transfer coefficient from common correlations are also compared to the present experimental data, acting as verification of the facility and methods used for the macroscale boiling flows investigated in this work. Laser-induced fluorescence (for the identification of the liquid phase) and particle image velocimetry (for the provision of velocity-field information) were also developed and successfully applied, providing detailed spatially- and temporally-resolved interfacial property, phase distribution and liquid-phase velocity-field data, alongside traditional integral pressure drop and overall heat transfer measurements. The laser-based methods provide new insight into the hydrodynamic and thermal characteristics of boiling flows at this scale, which are linked to the integral thermohydraulic data on flow regimes, pressure drops and heat transfer. This enhanced understanding can improve the design and operation of flow-boiling applications such as organic Rankine cycles and concentrating solar power facilities operating in the direct steam generation mode.
Date Issued
2021-07-25
Date Acceptance
2021-05-08
Citation
Applied Thermal Engineering, 2021, 194, pp.1-17
ISSN
1359-4311
Publisher
Elsevier BV
Start Page
1
End Page
17
Journal / Book Title
Applied Thermal Engineering
Volume
194
Copyright Statement
© 2021 Elsevier Ltd. All rights reserved. This manuscript is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Licence http://creativecommons.org/licenses/by-nc-nd/4.0/
Sponsor
Engineering & Physical Science Research Council (EPSRC)
The Royal Society
Identifier
https://www.sciencedirect.com/science/article/pii/S1359431121005263?via%3Dihub
Grant Number
EP/T03338X/1
AQ150077
Subjects
0913 Mechanical Engineering
0915 Interdisciplinary Engineering
Energy
Publication Status
Published
Article Number
117085
Date Publish Online
2021-05-19