Impact of the mixing theories on the performance of ejector expansion refrigeration cycles for environmentally-friendly refrigerants [Impact des théories de mélange sur les performances des cycles frigorifiques à détente par éjecteur pour des frigorigènes respectueux de l'environnement]

Küçük Resim Yok

Tarih

2019

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Elsevier Ltd

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

Ejector expansion refrigeration cycle was investigated theoretically to compare the constant pressure mixing and constant area mixing ejector theories making use of thermodynamic models. Performance improvement was presented according to optimum and constant value pressure drop assumptions in order to simulate the design and off-design conditions, respectively. The agreement between the results with respect to both pressure drop assumptions is better at higher condenser and lower evaporator temperatures for each ejector mixing theory. Optimum area ratio (?opt) is less for constant area mixing approach since the ratio of the secondary flow velocity to the primary flow is higher for this ejector theory at each operation point. Although a group of low-global-warming-potential refrigerants were compared in terms of the performance and expansion losses, deep investigations were presented for R1234yf in main and sometimes R1234ze(E). Finally, when compared to other ejector sections, the mixing section efficiency has the most critical effect on the optimum performance improvement ratio of R1234yf with reference to constant pressure mixing assumption. © 2018 Elsevier Ltd and IIR

Açıklama

Anahtar Kelimeler

Constant area mixing, Constant pressure mixing, Ejector expansion refrigeration cycles, Ejector section efficiency, Low-GWP refrigerants, Zero-dimensional (0D) modelling

Kaynak

International Journal of Refrigeration

WoS Q Değeri

Scopus Q Değeri

Q1

Cilt

97

Sayı

Künye