Precise surface temperature measurements at kHz-rates using phosphor thermometry to study flame-wall interactions in narrow passages

The thermographic phosphor ScVO4:Bi3+ is used to obtain time-resolved surface temperature measurements with sub-oC precision at 5 kHz. Measurements are study transient heat loss and flame-wall interactions (FWI) within a dedicated narrow two-wall passage (crevice) in an optically accessible fixed volume chamber. This emulates crevice relevant many technical environments, where FWI less understood due lack of detailed measurements. Chemiluminescence (CH*) imaging performed simultaneously thermometry resolve how the spatiotemporal flame features influence local temperature. benchmarked against Gd3Ga5O12:Cr,Ce, common low-kHz rates environments. shown offer higher luminescence signal levels sensitivity as well negligible cross dependence on excitation laser fluence, improving repeatability wall measurement. further for variations spacing uniquely capture transients associated dynamics. Taking advantage these precise flux calculated 1.2 mm, extinction prevalent. Wall estimated quenching distance reported flames that actively burn or extinguish measurement location.