A Historical Review on the Tribological Performance of Refrigerants used in Compressors

Abstract

Refrigerants directly affect the tribological performance of interacting components in a compressor. Since the introduction of artificially formulated refrigerants, the types of refrigerants used in compressors have changed over the years. Apart from evaluating the physical, chemical and thermodynamic properties of refrigerants, the refrigerants have also been studied from a view point of tribology by various researchers worldwide. Changing a refrigerant in a compressor not only has an effect on the thermodynamic cycle but also effects the lubricants viscosity, lubricants pressure-viscosity coefficient, oil film thickness, lubricant/refrigerant miscibility, friction, wear, durability, reliability and overall power consumption. Refrigerants have been studied from a view point of tribology by varying the contact geometries, by using different lubricating oils with and without additives, by altering the environmental pressure/temperature, by changing the phase of the refrigerant, by using different interacting materials and by applying numerous surface treatments. The tribological behavior of refrigerants can be better understood by consolidating the findings in a comprehensive manner. An indepth review on the tribological behavior of refrigerants is missing from the literature. This article reviews the tribological studies carried out on refrigerants, with focus on refrigerants used in domestic appliances, automobile air-conditioning systems and small scale industrial and commercial applications.

Reciprocating friction and wear performances of nanometer sized‐TiO2 filled epoxy composites

“…It could be in accord with the characteristic of the adhesive wear mechanism, which was a combination of microdelamination and microcutting. [ 42 ] Adhesive wear is caused by the fracture of the bonding joint due to the relative movement between the mating surfaces, while the formation and rupture of the junctions control the adhesion components of friction. [ 43 ] When two surfaces slide against each other, the actual contact is between the rough points of the two surfaces.…”

Wear Performance Analysis of Ni–Al2O3 Nanocomposite Coatings under Nonconventional Lubrication

“…Artificially formulated refrigerants have been forced to change over the years, due to their damaging environmental implications [2]. Chlorofluorocarbons (CFCs) and Hydrochlorofluorocarbons (HCFCs) were the first artificially formulated refrigerants that went into production in 1930s [2].…”

“…Artificially formulated refrigerants have been forced to change over the years, due to their damaging environmental implications [2]. Chlorofluorocarbons (CFCs) and Hydrochlorofluorocarbons (HCFCs) were the first artificially formulated refrigerants that went into production in 1930s [2]. In addition to having excellent heat transfer and thermodynamic properties CFCs and HCFCs also have phenomenal trigological properties [3,4,5,6,7,8,9,10,11,12].…”

“…CFCs have higher Ozone Depletion Potential (ODP) in comparison to HCFCs. Use of CFCs was banned by the end of year 1995 in developed countries and HCFCs can no longer be used after 2020 [2].…”

“…A number of studies were performed to evaluate the tribological behavior of hydrocarbons under various operating conditions [29,30,31,32,33,34,35,36,37,38,39,40]. Hydrocarbons are considered to be more efficient thermal conductors than HFCs [2], however hydrocarbons are highly flammable, which seriously restricts their commercialization. Carbon dioxide is another naturally occurring compound that has good thermodynamic properties and has a global warming potential (GWP) value of only one.…”