The main purpose of this paper is to present an experimental and numerical study on a fully premixed methane flame in an academic burner that resembles acoustically a Rijke tube. The research will focus on an investigation of the heat transfer in an internally-cooled cylindrical probe that is inserted in the combustion chamber and used as a sensible element to measure the heat flux. Due to the geometry of the burner, self-excited oscillations of the pressure take place in the combustor modifying the structure of the flow field and cause fluctuations of heat release and also of heat flux to the wall. Phase locked measurements of the OH~* chemiluminescence were performed and used to understand the structure of the flame under thermoacoustic instabilities. Several simulations have been performed varying the thermal boundary conditions with the attempt to correctly reproduce the main acoustics features of the burner. Particular attention was paid to the achievement of accurate solutions for unsteady heat transfer due to thermoacoustic instabilities.
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