Convegni ATI - Accesso riservato soci CTI

Autore: G. Montenegro, A. Onorati

Collana: CA - 62 - Fisciano 2007

Note:
This paper describes the development of a hybrid approach, in which a CFD code has been integrated with a 1D model and applied to the simulation complex muffler configurations. The HLLC solver was implemented in both models and exploited to handle the interface between the calculation domains. The two models have been used separately for the transmission loss prediction of simple muffler configuration, for which the linear acoustic behavior is well known. In particular an Helmholtz, a column
resonators and an Herschel-Quincke tube were simulated and the results compared to the linear acoustics theory, pointing out that in the eld of small perturbations the two models are equivalent. The integrated approach was successively used to predict the TL of more complex geometries, two expansion chambers with extended inlet and outlet pipes, pointing out a better prediction of the coupled approach if compared
to the results of fully 1D simulations. The integrated approach was also used for the prediction of a single cylinder engine performances, whose intake system included an Helmholtz resonator, showing a better prediction of the engine torque curve over a wide range of engine revolution speeds.