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.