1997-10-27

Prediction of Exhaust Pressure Pulses for Active Control of Exhaust Noise on a Small SI Engine 978460

This paper reports the work on modeling the exhaust noise pressure of a small single-cylinder SI engine. The model will ultimately be used for on-line prediction of exhaust noise in an active control system with a single-error microphone. The frequency properties of the engine exhaust noise generated by this SI engine are characterized by harmonic components related to engine firing conditions. The frequencies of the harmonic components depend only on the engine firing frequency while the amplitudes of the harmonic components vary with the engine load. The twenty harmonic components at the lower frequency band were used to model the exhaust pressure pulse which is a two-dimensional function of engine speed and load. The model is represented by a double Chebyshev polynomial. The instantaneous exhaust pressure at steady state for a fixed position in the exhaust pipe was predicted using this model and compared with the experimental data. The result of this comparison is regarded as satisfactory.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 43% off list price.
Login to see discount.
Special Offer: Purchase more aerospace standards and aerospace material specifications and save! AeroPaks off a customized subscription plan that lets you pay for just the documents that you need, when you need them.
X