Flame Propagation in Blends of R-152a, R-134a, and R-1234yf with Air

ABSTRACT

Some new, low-global warming potential refrigerants will be flammable, and the laminar burning velocity is a useful parameter for quantifying fire risk. Laminar burning velocity measurements have been made using a constant volume experiment with dry air and the refrigerant R-152a (CH₃CHF₂), pure and blended with R-134a (CH₂FCF₃), or R-1234yf (CF₃CFCH₂). The resulting burning velocity data deduced from the pressure rise in the chamber are presented for a range of fuel air equivalence ratio and loading of the less flammable refrigerant, for unburned gases at 298 K and 101 kPa as well as at 375 K and 253 kPa. For comparison, the 1-D, planar laminar burning velocity was numerically simulated using a recently developed kinetic mechanism that includes a wide range of refrigerants with air. The predicted burning velocities agree reasonably well with the experimental values, and the numerical results are used to understand the kinetic mechanism of the reaction of the refrigerants. Uncertainties in the experimental data from radiation heat losses as well as extrapolation to ambient conditions are explored.

KEYWORDS:

• Refrigerant flammability
• R-152a
• R-134a
• R-1234yf
• laminar flame speed
• burning velocity
• premixed flame

Acknowledgements

The authors obtained financial support under contract DE-EE0007615 from the Office of Energy Efficiency and Renewable Energy, U.S. Department of Energy, Buildings Technologies Office (Project Manager Antonio Bouza), as well as from the U.S. Department of Defense, Strategic Environmental Research and Development Program (SERDP), under contract W74RDV91831838, (Project Manager Robin Nissan).

Official contribution of NIST, not subject to copyright in the United States. Certain commercial equipment, instruments, and materials are identified in this paper to adequately specify the procedure. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/00102202.2023.2249591

Notes

¹ Tables of the burning velocity data are presented in the Supplementary Material.

Additional information

Funding

This work was supported by the Office of Energy Efficiency and Renewable Energy [DE-EE0007615]; Strategic Environmental Research and Development Program [W74RDV91831838].