RT Journal Article
T1 Thermodynamic analysis of an enhanced ejector vapor injection refrigeration cycle for CO2 transcritical operation at low evaporating temperatures
A1 Ávila Gutiérrez, Miguel
A1 Peris-Pérez, Bernardo
A1 Domínguez-Muñoz, Fernando
A1 Besagni, Giorgio
A1 Salmerón Lissén, José Manuel
K1 Termodinámica
K1 Refrigeración y máquinas frigoríficas
K1 Consumo de energía
AB The main drawback associated with CO2 refrigeration systems is related to their performance reduction during transcritical operation at warm climate conditions, which may be compensated by better cycle architectures such as the split-cycle with subcooling or the flash-tank configuration, among others. Specifically, the use of standard gas-ejectors together with parallel compressors provides even better efficiency improvements, not being able to use them with low-temperature evaporators to prevent the triple point inside the ejector. This paper proposes an enhanced cycle with a gas ejector for two-stage compressor architectures with vapor injection from the flash- tank, which is able to operate at low evaporating temperatures and that provides a greater performance improvement the more severe the climate conditions are. The methodology conducted is based on a thermo- dynamic analysis that includes parametric evaluation and cycle optimization, comparing the results to a con- ventional CO2 transcritical cycle with flash-tank and dynamic vapor injection architecture. The main results show that a maximum Coefficient of Performance improvement of 17.5% is achievable for transcritical operation at -40 ◦C evaporating temperature. The compressor displacement capacity required with the enhanced cycle is up to 9% lower for the same refrigeration demand, reducing the electrical consumption as well as the compressor expenditure. Moreover, greater vapor injection mass flow rates are obtained by the gas-ejector injection with discharge temperature reductions up to 18%, enhancing the system reliability.
PB Elsevier
YR 2024
FD 2024-06-11
LK https://hdl.handle.net/10630/39724
UL https://hdl.handle.net/10630/39724
LA eng
NO International Journal of Refrigeration 165 (2024) 257–276
NO https://openpolicyfinder.jisc.ac.uk/id/publication/12611
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 19 ene 2026