R1234yf has a high COPHP compared to R134a at the 10 °C evaporator temperature while it has a low COPHP at 5 °C and 0 °C evaporator temperatures. R513A and R1234yf refrigerants have 14.45% and 17.16% less emissions than R134a, respectively....
This paper examines the detailed effects on the compressor performance when using R1234yf as comparedto R134a. Firstly, the effects on the compressor performance of the existing compressors which was designed for R134a when using the new refrigerant R1234yf will be presented and discussed. Secondly...
The results indicate that HFO-1234yf system in an actual cycle has the highest COP. HFO-1234yf and HFO-1234ze[E] have such smaller capacity per unit of swept volume that they need larger compression capacity if providing the same heating or cooling loads. For a given unit when HFC-134a ...
temperature circuit and HFC-134a in the low temperature (173K) circuit for cryogen applications .The thermodynamic analysis using entropy generation for finding exergy destruction ratio indicating that R1234ze (GWP=6) gives better performance than R-1234yf (GWP=4) in the high temperature circuit....
With the influences of the global warming, the researches of replacing the refrigerant for current air conditioning system are increasingly in-depth. The feasibility of using hydrocarbon mixture to replace HFC-134a was discussed from the theory and practical. And it has proved that the mixed of pr...
Indirect heat pump (IDS-HP) using R290 is introduced to replace direct HP (DS-HP).DS-HP using R1234yf is a baseline cabin heating system for electric vehicles.Heating performances of DS-HPR1234yfand IDS-HPR290are analyzed and compared.COP increase of IDS-HPR290over DS-HPR1234yfis 6.7–...
For the R134a centrifugal chiller, the drop-in replacement of R134a with R1234ze(E) can obtain better system performance compared with R1234yf. Keywords: centrifugal compressor; chiller; refrigerant; R1234yf; R1234ze(E); R134a1. Introduction R134a is an HFC (hydrofluorocarbon) refrigerant ...
However, the fourth generation refrigerants, such as R1234yf and R1234ze, are more expensive than second and third generation refrigerants. In addition, natural refrigerants also have critical limitations, such as their toxicity, combustibility, and operating pressure. Therefore, continuous research on...
Disawas and Wongwises (2005) performed experimental research on the performance of a refrigeration cycle using an ejector with R-134a as a refrigerant and the obtained results indicated that the performance of the system using an ejector was better than that of the conventional system. Elbel and...
Energy efficiency and heat transfer analysis of R-513A and other low GWP refrigerants alternative to R-134a in HVAC&R systems: A review An overview of low global warming potential (GWP) refrigerants focused on R-513A, and other low GWP refrigerants such as R-1234yf, R-1234ze(E), R-29...