Pumped thermal energy storage (PTES) is a technology for intermediate of electrical in the form energy. In this work, PTES systems based on transcritical CO2 charging process are investigated. A two-zone water tank with temperature 115°C used as storage. For discharge, an Organic Rankine Cycle (ORC) and, alternatively, heat engine The considered concepts modelled and simulated stationary proces...

This study provides a global warming impact analysis of environmentally friendly refrigerants used as replacements for R134a and R245fa. R290, R1234yf, R1234ze(E), R513A R450A are considered to replace in medium temperature applications. For R245fa, there five alternative refrigerants, R1224yd(Z), R600, R1336mzz(Z), R1233zd(E) R1234ze(Z), which selected high-temperature The is done considering ...

Due to its low global warming potential (GWP) and good environmental properties, CF3I can be a suitable component of refrigerant mixtures in the field refrigeration air conditioning. In this work, local condensation heat transfer characteristics were experimentally investigated plate exchanger (PHE). The experiments carried out under conditions vapor qualities from 1.0 0.0, at saturation temper...

In this study, the experimental performance of use R1234yf refrigerant al-ternative to R134a in an automobile air conditioning system with var-iable capacity compressor was investigated. The conditioner con-sists a variable compressor, evaporator, condenser, liquid tank and expansion element. is equipped computer-aided control systems obtain desired conditions data col-lection for measuring col...