Share

IIR document

Numerical assessment of CO2-based mixtures for refrigeration systems: focus on the evaporation process.

Number: 0544

Author(s) : VACCARO G., ANDREINI N., CARAMASCHI M., TALLURI L., ELMEGAARD B., MILAZZO A.

Summary

A large number of refrigeration systems operate on a stream that is not changing phase, i.e. has a finite heat capacity. The matching between the cooled stream and the evaporation of a pure refrigerant causes therefore significant irreversibility in the heat exchange. The use of mixtures is a well-known option for the mitigation of this problem. In this work, the use of a CO2-based mixture is proposed to allow the possibility of matching variable-temperature heat sources with the glide of the working fluid in the evaporator to minimize the heat exchange irreversibility. Modelling of a mini-channel evaporator by means of numerical techniques, accounting for the variable fluid composition, is presented. Several flow boiling correlations are assessed for pure CO2 (170<G<900) and CO2-propane blends (200<G<650). An optimized correlation for CO2-propane is proposed. As a final result, a high fidelity CO2 correlation for flow boiling is presented, which is also able to predict quite accurately the CO2-propane mixture heat transfer coefficient.

Available documents

Format PDF

Pages: 12 p.

Available

  • Public price

    20 €

  • Member price*

    Free

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Numerical assessment of CO2-based mixtures for refrigeration systems: focus on the evaporation process.
  • Record ID : 30031631
  • Languages: English
  • Subject: Technology
  • Source: Proceedings of the 26th IIR International Congress of Refrigeration: Paris , France, August 21-25, 2023.
  • Publication date: 2023/08/21
  • DOI: http://dx.doi.org/10.18462/iir.icr.2023.0544

Links


See other articles from the proceedings (492)
See the conference proceedings

Indexing