Experimental and comparative analysis of choked flow models in CO₂ expansion
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21220%2F25%3A00383667" target="_blank" >RIV/68407700:21220/25:00383667 - isvavai.cz</a>
Result on the web
<a href="https://doi.org/10.1007/s00231-025-03575-3" target="_blank" >https://doi.org/10.1007/s00231-025-03575-3</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1007/s00231-025-03575-3" target="_blank" >10.1007/s00231-025-03575-3</a>
Alternative languages
Result language
angličtina
Original language name
Experimental and comparative analysis of choked flow models in CO₂ expansion
Original language description
Predicting the speed of sound in two-phase flows is critical for optimizing systems involving refrigerants or high-pressure working fluids, such as transcritical cycles and ejector-based technologies. Carbon dioxide has emerged as a promising working fluid due to its favorable thermodynamic properties; however, its non-ideal behavior in two-phase states complicates the prediction of properties like the speed of sound. This study experimentally investigates the choked flow parameters and compares them with two Homogeneous Equilibrium Models (HEM) and the classic thermodynamic approach, focusing on their application in transcritical CO₂ expansion systems. A high-pressure experimental setup was designed to analyze CO₂ flow dynamics, incorporating precision instrumentation for stagnation pressure, temperature, and mass flow measurements. Experimental results were validated against theoretical predictions using the HEM, alongside the classic thermodynamics’ model, to identify their accuracy in predicting flux flow and choked pressures. Results reveal that Wallis’ model better aligns with pressure predictions at lower operating pressures. Conversely, Katto’s model proves more accurate for mass flow rate estimations. The findings emphasize the need for model refinement to address high-pressure regimes and highlight the critical role of accurate experimental data in advancing the design of CO₂-based energy recovery systems.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
20303 - Thermodynamics
Result continuities
Project
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Continuities
S - Specificky vyzkum na vysokych skolach
Others
Publication year
2025
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Heat and Mass Transfer
ISSN
0947-7411
e-ISSN
1432-1181
Volume of the periodical
61
Issue of the periodical within the volume
6
Country of publishing house
CH - SWITZERLAND
Number of pages
19
Pages from-to
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UT code for WoS article
001499209500001
EID of the result in the Scopus database
2-s2.0-105006731098