LAUSR

Efforts to meet ever-stringent fuel economy standards has led to increased focus on light weighting technologies, and proliferation of alternative powertrains such as hybrid vehicles. This has significantly increased the complexity of designing exhaust systems to meet high level NVH performances against thin powertrain targets. In this paper, some applications will be presented with latest efforts in addressing some of these challenges. (a) Novel methodologies in predicting exhaust high frequency flow noise using transient CFD simulations will be discussed. (b) Customized tuning applications: Case study in optimization, Daisy-chaining, and positioning of narrow frequency tuning applications (e.g., concentric tube Helmholtz resonators with tuned orifices, pipe length tuning) driven by tighter clearances and directed light weighting efforts will be discussed. (c) Hybrid applications—Hybrid powertrains pose a unique challenge as the engine can function both as power plant and a power generator, both of which...