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Nonlinear mode interaction caused by friction at blade-root attachments is a common phenomenon in current bladeddisk configurations. However, it is still far from been completely understood, and the application of simple linear superposition can lead to an overestimation of the system vibrational response. In this work, nonlinear mode interaction is analyzed using a simplified mass-spring model with a microslip friction model. The parameters of the model are set using data from actual experimental results from a realistic bladed-disk, which are rarely available. Two different configurations are considered. The interaction of the synchronous response of the system due to harmonic excitation with a nonsynchronous aerodynamically unstable mode, and the interaction of two synchronous harmonic excitations with similar frequencies and different engine orders.

A 2D slip-sweep simulation experiment was recorded in the Mabruk field in Libya. In order to prepare this experiment, a preliminary analysis was conducted using synthetic data. Various types of noise were isolated and the corresponding data contamination analyzed. Signal-tonoise ratio maps were generated for various slip-sweep configurations. The same analyses were conducted on the actual data after slip sweep simulation, correlation and standard processing. Considering a 10 second slip time, the noise added to the data was lower than-20 dB.

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