07 May 2025

Modeling Leaks of Flammable Refrigerants

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Hydrocarbons (HC) are being introduced as refrigerant in heat pumps and AC systems, as a part of the phase-down of synthetic refrigerants. As HC are highly flammable, standards are being refined for their safe use. To better understand the risks, computational fluid dynamics (CFD) can be used to determine the concentrations of flammable refrigerants during the release in case of a leak. In this article, we will give a brief overview of work done in the US, as well as provide examples of results which have been achieved using CFD in Europe. This work is part of the IEA HPT Annex 64 on Safety Measures for Flammable Refrigerants.