A paradox of the assessment of the emissivity of the flames is that this is based on the measured flame temperature. The emissivity of flames is not a generic property that can be assessed without measuring the flame temperature, so the correct assessment of flame temperature is part of the chain to obtain the correct value. In many of the experiments reported in the literature, flame temperatures have been measured with thermocouples embedded within the flame envelope, assuming that the flame surrounding is close to optical thick, which is assuming a flame emissivity close to unity. This leads to a possible error of the assessment of flame emissivity, which consequently leads to uncertain assessment of radiation from flames.
展开▼
