Vapor compression heat pumps with refrigerant mixtures

Refrigerant mixtures are widely considered as the next-­generation environment-­friendly refrigerants because they allow to tune refrigerant properties for the best compromise between conflicting goals: lower global warming potential (GWP), zero ozone depletion potential (ODP), low or no flammability and toxicity. Nevertheless, refrigerant mixtures can behave quite differently during evaporation and condensation than pure refrigerants. This paper first discusses key differences between pure and mixed refrigerants, presents a case study on the impact of mixtures on heat exchanger design and quantifies the potential efficiency losses/gains using a large temperature glide mixtures. The paper further details the benefit of mixtures on capacity control.