Imperial College London

ProfessorChristosMarkides

Faculty of EngineeringDepartment of Chemical Engineering

Professor of Clean Energy Technologies
 
 
 
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Contact

 

+44 (0)20 7594 1601c.markides Website

 
 
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Location

 

404ACE ExtensionSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@inproceedings{Taleb:2016,
author = {Taleb, A and Barfuß, C and Sapin, P and Willich, C and White, AJ and Fabris, D and Markides, CN},
title = {The Influence of Real Gases Effects on Thermally Induced Losses in Reciprocating Piston-Cylinder Systems},
url = {http://hdl.handle.net/10044/1/32649},
year = {2016}
}

RIS format (EndNote, RefMan)

TY  - CPAPER
AB - The efficiency of expanders is of prime importance for variousclean energy technologies. Once mechanical losses (e.g. throughvalves) are minimized, losses due to unsteady heat exchange betweenthe working fluid and the solid walls of the containingdevice can become the dominant loss mechanism. In this device,gas spring devices are investigated numerically in order to focusexplicitly on the thermodynamic losses that arise due to thisunsteady heat transfer. The specific aim of this study is to investigatethe behaviour of real gases in gas springs and comparethis to that of ideal gases in order to attain a better understandingof the impact of real gas effects on the thermally losses inreciprocating piston expanders and compressors. A CFD-modelof a gas spring is developed in OpenFOAM. Three different gasmodels are compared: an ideal gas model with constant thermodynamicand transport properties; an ideal gas model withtemperature-dependent properties; and a real gas model using thePeng-Robinson equation of state with temperature and pressuredependentproperties. Results indicate that, for simple, monoanddiatomic gases like helium or nitrogen, there is a negligibledifference in the pressure and temperature oscillations over a cyclebetween the ideal and real gas models. However, when lookingat a heavier (organic) molecule such as propane, the ideal gasmodel tends to overestimate the temperature and pressure comparedto the real gas model, especially if no temperature dependencyof thermodynamic properties is taken into account. Additionally,the ideal gas model (both alternatives) underestimatesthe thermally induced loss compared to the real gas model forheavier gases. Real gas effects must be taken into account in orderto predict accurately the thermally induced loss when usingheavy molecules in such devices.
AU - Taleb,A
AU - Barfuß,C
AU - Sapin,P
AU - Willich,C
AU - White,AJ
AU - Fabris,D
AU - Markides,CN
PY - 2016///
TI - The Influence of Real Gases Effects on Thermally Induced Losses in Reciprocating Piston-Cylinder Systems
UR - http://hdl.handle.net/10044/1/32649
ER -