Design of Rectangular Cross Section Helical Resonator for Noise Attenuation in Air Induction System

Noise pollution is a prominent environmental hazard faced by the automobile industry. The design of automotive Air Induction Systems (AIS) plays a crucial part in attenuating noise emitted by an engine. In addition to this, sound attenuating devices are connected in series and in parallel to the AIS for effective noise attenuation. This paper presents three-dimensional (3D) acoustic and flow results of one such sound attenuating device, the Helical Resonator (HR), which is attached to the AIS of a 3.6 L engine replacing the existing Helmholtz resonators (HHR). The baseline AIS has four HHRs to attenuate four major engine noise frequencies. In this paper, design parameters were selected to allow the HR to capture at least two of the four frequencies and minimize the cost at space concerns. The analytical four-pole Transfer Matrix Method (TMM) approach is applied to initially calculate Transmission Loss (TL) and arrive at a suitable set of HR design parameters. This allows us to understand the sound attenuation capability of the HR. Fine-tuned design parameters of the HR are implemented in the full AIS using GT-POWER® in the frequency range of 0 to 1000 Hz. Siemens 3D Simcenter® is used to estimate the impact of the HR on noise attenuation for correlation. STAR-CCM+® is used to estimate the amount of pressure drop contributed by the HR. This design can be used for future applications if the additional pressure drop due to HR is within permissible limits.