The Panel Noise Contribution Analysis (PNCA) is a well-known methodology for an airborne Transfer Path Analysis (TPA) in car interior. Pressure contribution from the individual panels at a reference point can be very accurately calculated. Acoustic Trim package treatment can therefore be optimized in terms of frequency and panel area which saves money and time. The method uses only one type of sensors so called particle velocity probes for measuring source strength as well as transfer function (with a reciprocal measurement).
Traditionally the PNCA makes use of a big amount of probes at fixed points (about 50) hence non-stationary conditions can be measured as well. Typically the measurement is performed in 3 sessions resulting in 150 individual panels. Because of the low spatial resolution the method can only be used at mid-low frequency range.
The new Panel Noise Contribution Analysis Referenced (PNCAR) implements a new post-processing technique which uses a reference sensor in order to extract the relative phase information for the individual panel and frequency of interest. This technique makes it possible to use a limited amount of probes for measuring a whole car interior. Typically 11 probes are used in 11 sessions. Consequently, the methodology becomes more robust and commercially more affordable than conventional PNCA.
A real measurement in driving condition was done on the highway in order to validate the methodology. Two different approaches to apply the theory derivations are compared and discussed.
