Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
ANALYSIS OF THE EFFECT OF PRESSURE DROP IN EJECTORS ON THE PERFORMANCE OF VAPOR COMPRESSION REFRIGERATION SYSTEMS
Submission Author:
Débora Carla Silva Mól , MG
Co-Authors:
Débora Carla Silva Mól , Paulo Eduardo Lopes Barbieri, Ralney Faria, Tiago de Freitas Paulino
Presenter: Débora Carla Silva Mól
doi://10.26678/ABCM.ENCIT2022.CIT22-0119
Abstract
The ejector is a device known to operate minimizing the energy losses caused by the expansion process in vapor compression refrigeration systems, thus resulting in an increase in the coefficient of performance (COP). The pressure drop in the suction nozzle (∆P), condensation and evaporation temperature are parameters that directly influence the performance of these systems. However, although there is an optimal ∆P that makes the COP of a refrigeration system reach its maximum value for each operating condition, to determine it is necessary to perform a search within a wide range of ∆P or through the use of optimization methods, which can be exhausting. Thus, this article presents an alternative that seeks to facilitate the determination of ΔP that maximizes the COP for different refrigerants and operating conditions (condensation and evaporation temperatures), by specifying an equivalent temperature difference ΔTeq determined by the saturation pressure. Thus, the mathematical modeling is established and from the simulations carried out in the EES software, with the refrigerants R134a, R290 and R1234ze(E), it is possible to conclude that the performance of the system improves with the increase of the evaporation temperature and with the decrease of the condensation temperature. Furthermore, the results showed that a value of 0.5K for ΔTeq is ideal to meet all operating ranges and evaluated fluids.
Keywords
ejector, Refrigeration, pressure drop
