This research work presents a study on detection of nonlinearities in structural components and assemblies. The detection and location of nonlinearities should be considered an important step during the design stage when models need to be calibrated or updated. The correct validation of a Finite Element model enables reliable predictions of vibration responses. The validation process is nevertheless challenged for a number of reasons; one can be the presence of nonlinearities. There are many types of nonlinearities but the one looked at in here regards the discrete ones, where the localization is important in order to correctly perform the model validation. This research work will focus on how to locate sources of nonlinearities from an aero-engine casing equipped with mock-ups of pipe. The major objective of the paper is to present the Scanning Laser Doppler Vibrometer as useful measurement tool for locating sparse nonlinearities. The work aims to demonstrate how it should be possible to develop an indicator for detecting sources of nonlinearity from experiments. Eventually, this pilot study will lead to the development of a new metric for nonlinear modal testing based on scanning laser.
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