In experimental noise analysis of vehicular components the aim is to pick up the local domains, that contribute most to the noise emitted. The acoustic intensity, acoustic pressure, vibration velocity is usually measured. The Modal Assurance Criterion (MAC) computation, used for comparing nodal shapes measured vs. modeled can be easily extended for evaluating these results. The identical algorithm can be used for any suitable physical Parameter (velocity, intensity, pressure etc.) and for any coordinate of measured values (local domain, frequency domain etc.); the orthogonality of shapes is a similar well known application. The MAC extended to Mcc (Mutual Correspondence Criterion) values can be mapped e.g. In the local domain (compare accoustic Intensity with accoustic pressure for all/selected frequency bands) or in frequency domain (compare accoustic pressure with vibration velocity for all/selected local parts of the structure) etc. The example based on the truck motor measurement is presented.
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