Optical and probe techniques are used to analyse the coupling mechanism between pressure, velocity and temperature fluctuations typical of pulsed flames, through the combination of laser velocimetry, digitally-compensated thermocouples and a proble microphone. The s ystem is based on a digital signal microprocessor and is shown to run up to 12.5 kHz of data ready velocity signals, allowing the time-resolved representation of vectors of turbulent heat flux along a typical cycle of oscillation. The detailed results obtained along the oscillating reacting shear layer show time sequences of zones characterised by gradient and non-gradient turbulent heat flux, which are structurally similar to previous results reported in the iterature for steady recirculating flames.
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