This investigation presents a theoretical evaluation of the use R450A replace to R134a in low and medium temperature heat pump systems. The energy, exergy, environmental enviro-economic analyzes pumps have been performed for two refrigerants (R134a its alternative R450A). thermodynamic analyses made source temperatures (10 oC 20 oC) six sink (from 30 55 oC). It has observed that R450A's mass fl...

Due to the Kigali amendment Montreal Protocol, refrigerants such as R134a are targeted for phasedown or phaseout due their global warming potential (GWP) and lower GWP being considered replace R134a. Since condenser is typically responsible 50% of charge a refrigeration system, it vital have fundamental understanding flow condensation heat transfer performance low R513A R450A. Experimental coef...

It will bring about many problems for a Rl2 refrigerator compressor to use Rl34a as refrigerant directly, such as power increasing, capacity dropping, and noise rising up etc. In order to solve these problems, the mathematical model, optimization model and special test system were built up, many improvements were made by means of the calculating and the testing results. Finally, the performance...

Discharge gas temperature value is an indicator of compressor safe operating conditions, particularly on R12 and R502 commercial applications. These refrigerants will be replaced very soon by R134a and R22 respectively, also if R22 is not considered a final solution. High discharge temperatures are typical in LBP-R22 hermetic compressors operating at low evaporating temperature as low as -40"C;...

This paper investigates the results of a Second Law analysis applied to a mobile air conditioning system (MACs) integrated with an internal heat exchanger (IHX) by considering R152a, R1234yf and R1234ze as low global warming potential (GWP) refrigerants and establishing R134a as baseline. System simulation is performed considering the maximum value of entropy generated in the IHX. The maximum e...

Two-phase pressure drop was measured across a micro-channel heat sink that served as an evaporator in a refrigeration cycle. The micro-channels were formed by machining 231lm wide · 713lm deep grooves into the surface of a copper block. Experiments were performed with refrigerant R134a that spanned the following conditions: inlet pressure of Pin = 1.44–6.60bar, mass velocity of G = 127–654kg/m ...

Nanofluids are considered as a new invention of fluids having superior thermal physical properties to improve efficiency the refrigeration system. colloidal suspensions nanoparticles in base fluid. Nanoparticles higher conductivity compared pure refrigerant such R134a can be added performance This study focuses on producing nanolubricant (SiO2/POE) and implementing into The will homogenized pro...

Abstract With global warming and climate change, the world is experiencing a steady temperature rise. Hence need for effective efficient air conditioning, cooling refrigeration systems higher than ever. One of key elements influencing system performance working fluid. From 2022, new in UK must not use fluids with potential (GWP) above 150. Widely used R134a, GWP 1430, therefore being banned sui...