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Environmental concerns related to global warming and ozone depletion triggered the introduction of the fourth generation of thermofluids. amongst the recently introduced thermofluids, one of the most promising fourth generation of thermofluids are hydrofluoroethers (HFEs). HFEs have zero ozone depletion potential and have a lower global warming potential as compared to widely used thermofluids. The type of thermofluid used in a thermodynamic cycle directly affects the tribological performance of the system. HFEs have been reported to have good thermodynamic properties. The overall tribological performance of HFEs however have to be investigated in detail in order to fully assess the mechani- cal behaviour of interacting components utilizing these thermofluids. This study is concerned with the experimental test rig design modifications and commissioning to conduct tribological testing with HFEs as lubricants. This article covers the experimental test rig design and setup. Experiments to analyse the frictional force, the coefficient of friction and wear by using hydrofluororther-7000 (hfE-347mcc3) as lubrication medium have been conducted. Industrial applications were simulated by varying test condi- tions and the results are presented in this paper.
bench testing, environment-friendly thermofluids, friction, refrigerants, tribology, wear
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2018. doi: 10.3390/ma12010036