This study focus on the experimental determination of the Flame Transfer Function (FTF) which can be used to analyze acoustic induced combustion instabilities. In the present work random non-harmonic velocity signals are generated to perturb the flame. This method enables to rapidly determine the FTF compared to other techniques and improves the frequency resolution. A System Identification (SI) technique is applied to model the frequency response of different components of the test bench. It is firstly used to impose a white noise velocity signal at the burner exit, with a tunable perturbation level. SI tools and spectral analysis are used to reconstruct the FTF of a laminar conical flame. Experiments are conducted for different operating conditions and forcing levels. Results are compared with those obtained by harmonic modulations of the flow. They closely match over a large frequency range for small perturbation levels. The limits of the technique are examined when the modulation amplitude is increased.

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