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15 years of NVH applications make Transfer Path Analysis (TPA) appear a commodity tool. But despite the fact that TPA is today successfully used in a large variety of applications in automotive and mechanical industries, its main bottleneck remains the huge measurement time to build the full TPA model. This paper presents a new TPA method that provides a good compromise between path accuracy and measurement time. The method is also referred to as OPAX. The key idea of OPAX is the use of simplified parametric load models with limited number of model parameters. The main advantage of this is that one should measure only a small amount of FRF data to identify the operational loads. This drastically reduces measurement time and efforts. In addition to this, the OPAX method does not require mount stiffness data and allows a simultaneous identification of structural and acoustic paths.

Despite the fact that Transfer Path Analysis (TPA) is a well known and widely used NVH tool it still has some hindrances, the most significant being the huge measurement time to build the full data model. For this reason the industry is constantly seeking for faster methods. The core concepts of a novel TPA approach have already been published in a paper at the ISMA 2008 Conference in Leuven, Belgium. The key idea of the method is the use of parametric models for the estimation of loads. These parameters are frequency independent as opposed to e.g. the classical inverse force identification method where the loads have to be calculated separately for each frequency step. This makes the method scalable, enabling the engineer to use a simpler model based on a small amount of measurement data for quick troubleshooting or simply increase accuracy by a few additional measurements and using a more complex model.

Aircraft noise modeling aims to provide designers with computational tools that allow exploring the design parameters domain early in the design and development process. A number of modeling techniques are available for acoustics and vibration prediction, but in order to define objective targets for sound quality perception, dedicated tools are still needed to correlate structural models and design modifications with human perception of sounds. This paper presents a model-based sound synthesis concept for interior and exterior aircraft noise that allows interactive, real-time sound reproduction and replay. The proposed approach is presented through two application cases: jet flyover noise and turboprop interior noise.