Vapor-liquid equilibrium for R-32 and R-410A mixed with a polyol ester: non-ideality and local composition modeling

Solubility of carbon dioxide in 2-methylbutyric, 2-methylvaleric and 2-methylhexanoic ester oils

“…Few data are available on the thermophysical properties of the refrigerant + lubricant systems [1][2][3][4][5][6][7][8][9][10][11], and most of them refer to hydrofluorocarbons (HFC) and commercial oils. However, the structure and composition of the commercial oils is usually not defined, since they are mixtures of different components and additives, and this complicates the development of reliable thermodynamic models able to predict the behaviour of the lubricant + refrigerant mixtures.…”

Solubility and Miscibility of Refrigerants R407c and R410a With Synthetic Compressor Oils

“…The main conclusions based on these reviews are the follows: (1) the most solubility data were obtained for the mixtures of the pure refrigerant (mainly R134a) with the POE lubricants by different producers, but it is impossible to systemize these results; (2) only limited information is available for the solubility of mixed refrigerants with the POE lubricants [1][2][3][4][5]; (3) miscibility limit at high temperatures (upper critical solution temperature UCST) and LCST until resent time practically were not studied. The exception are the work [6], where a limited experimental data were obtained for the UCST of the CO 2 with the POE oils ISO 46 and ISO 68, and the research [7] for LCST of R134a with two samples of POE ISO 22.…”

“…Vapor pressure is measured using calibrated, constant volume cells with the volume of approximately 25 cm 3 , placed in the temperature bath and connected to the sensitive (to within ±1 kPa) pressure transducer. The design of this measuring device eliminated the condensation of the refrigerant in the line connected the cell and the pressure transducer.…”

A numerical study on oil retention and migration characteristics in the heat pump system

“…Furthermore, continuity equation and momentum equation are also used to calculate mass flow rate and pressure drop as shown in Eqs. (6)- (8).…”

“…Additionally, oil return characteristics in vertical upward flow were experimentally and theoretically investigated by Mehendale et al The critical mass flow rate for preventing oil film reversal in a vertical pipe for vapor refrigerant with R-22, R-407C, and R-410A with MO and POE was pointed and was compared with the results by Jacobs et al [6][7]. Burton et al have studied vapor-liquid equilibrium for R-32 and R-410a with POE oil and compared some preexisting correlations [8]. Fukuta et al suggested measurement method for oil-refrigerant mixture concentration ratio using refractive index [9].…”