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Noise-vibration-harshness (NVH) is now playing an important role in electric vehicle development process. Experience shows that the NVH criteria must be considered at the very early stages of the concept design phase. Finite Elements (FE) models are widely used to simulate the vehicle design. To achieve a correct accuracy of a FE model, the results of an experimental modal analysis (EMA) are commonly applied to a FE model via correlation and updating processes. Thus, different kinds of optimization might be used throughout the concept design duration. This paper describes, first, the use of a parametric optimization to tune a FE model in high frequencies relying on the results of the EMA test. Then the frequency response analysis is conducted to detect the critical frequencies for the NVH performance. Based on the results of this analysis, a topographic optimization is performed.

In vibroacoustic, bandgap effects related to periodic and/or locally resonant architectural materials can lead to new types of structural vibration filters. This communication concerns periodic pipes used in industrial context. Such pipes are seen, as architectural structural waveguides in which flexural, torsional, and longitudinal waves can propagate. To control the propagation of these vibrations and reduce their possible noise disturbance, Bragg or resonant band effects can be obtained by architecting the axial variations of the cross-section. As a result, a waveguide can be tuned to create stop bands with bandwidths large enough to make them interesting for industrial applications. For this purpose, dispersion relations are derived and analyzed based on the Floquet method and numerical Finite Element simulations. In many practical cases, all kinds of waves generally coexist due to the inevitable structural couplings.

Virtual NVH Engineering is going to be reviewed in this paper for the development of FIE (fuel injection equipment) components. Some examples based on high pressure pumps and SCR air cooling injectors will illustrate the explanation. The use of a 3D FEM vibro-acoustic model is essential to support virtual NVH Engineering. Therefore, a review of techniques to study components is done first. Model correlation is also an important topic which will be discussed and which makes any NVH engineer confident in using a model instead of real HW. It is quite challenging to establish these models, as they must mimic the entire physical phenomenon of real structure borne hardware sound in the whole audible frequency range. Limitations of models are also identified and allow answering one true question: Should we stay considering only each component separately or as an assembly of parts of a larger system in the development process?

Either from a legislative point of view or because of OEM demands, the automotive industry is increasingly facing of reducing vibration & noise in the vehicle. More particularly on the engine area, the development of Gasoline and Diesel fuel components based on high pressure pumps, rails, any pipes and injectors are more and more subject of a particular NVH (Noise Vibration and Harshness) attention. The use of modern digital techniques such as 3D FEM vibroacoustic, leads to use virtual prototyping as complementary to traditional real hardware prototypes development. Among interest, number of iterative loops to reach a best design brings an important value to new product development with an optimized cost. Basically the core part of virtual prototyping is about a 3D FEM model definition for each component. It is quite challenging to establish these models, as they must mimic the entire physical phenomenon of real structure borne hardware sound in the whole audible frequency range.

In the automotive industry simulation represents an essential tool for the development process of the functions designed and integrated within the Engine Control Unit (ECU). This approach applies to each stage of the development cycle to establish the possible physics which are modeled accordingly. The particular stage which relates to the validation of the Engine Control Unit uses test benches called Hardware In the Loop (HIL) systems. They simulate both engine and vehicle by means of integrated models. The characteristics of these benches represent the constraints for the real-time computation of these models, in particular when the Engine Control Unit test requires a highly detailed physical model. This paper attempts to treat the introduction of plant models based on a more accurate physical representation of the internal combustion engines into a Hardware In the Loop target.