Effects of stretch and thermal radiation on difluoromethane/air burning velocity measurements in constant volume spherically expanding flames.

Compared to current refrigerants, next-generation refrigerants are more environmentally benign but more flammable. The laminar burning velocity is being used by industry as a metric to screen refrigerants for fire risk, and it is also used for kinetic model development and validation. This study reports measurements of difluoromethane/air flame burning velocities for equivalence ratios from 0.

Understanding overpressure in the FAA aerosol can test by CHFBr (2-BTP).

Thermodynamic equilibrium calculations, as well as perfectly-stirred reactor (PSR) simulations with detailed reaction kinetics, are performed for a potential halon replacement, CHFBr (2-BTP, CHFBr, 2-Bromo-3,3,3-trifluoropropene), to understand the reasons for the unexpected enhanced combustion rather than suppression in a mandated FAA test. The high pressure rise with added agent is shown to depend on the amount of agent, and is well-predicted by an equilibrium model corresponding to stoichiometric reaction of fuel, oxygen, and agent. A kinetic model for the reaction of CHFBr in hydrocarbon-air flames has been applied to understand differences in the chemical suppression behavior of CHFBr vs.